m »wM i i&iMSs ' * . s * <.vy ■ ^ ':/ ; : \^- ^ '•" ,^ "%. '<£> ^ A ■ < " ' C- V' % S - %; %*** :i - ^>.^ v "-V .0 O \ \^«-y / -^ *•» t'\ " ^ ".**' N q. '->" ^ ^ /W v- V .0- -o. '" •» , \^' ■ k -v\ STEEL RAILS THEIR HISTORY, PROPERTIES, STRENGTH AND MANUFACTURE WITH NOTES ON THE PRINCIPLES OF ROLLING STOCK AND TRACK DESIGN WILLIAM H. SELLEW PRINCIPAL ASSISTANT ENGINEER, MICHIGAN CENTRAL RAILROAD 361 ILLUSTRATIONS -83 FOLDING PLATES NEW YORK D. VAN NOSTRAND COMPANY Twenty-five Park Place LONDON CONSTABLE & COMPANY, Ltd. 1913 .S4 Copyright, 1913 D. VAN NOSTRAND COMPANY \ ( Stanbope ipress . H.GILSON COMPANY SCi.A:M6058 PREFACE In this work the author has endeavored to systematize the knowledge in existence upon the subject, and to present in a concise yet clear form the most important features of the problem. The first chapter treats of the development of the present design of section with a comparison of the American rails with those in use on English Railways and on the Continent. In chapters two to five, inclusive, the external forces acting on the rail and the corresponding stresses they produce in the rail are discussed. The necessity and desire for information on this subject are widespread. While a considerable amount of general information is to be found scattered through the technical press and in the proceedings of the various Railway Associations and Engineering Societies,, yet very little has been published dealing broadly with the principles of design of the jail in reference to the rolling stock and track structure. In recent years much thought has been given to the manufacture of rail steel, and investigators, it would seem, have turned their attention more to an examination of the various defects found in the process of manufacture than to the study of the duty of the rail. Quite early the question of the intensity of pressure existing between the wheel and the rail began to receive attention, but it was not until later that the bending stresses in the rail were investigated. Purely theoretical contributions to the latter subject were made by Zimmerman in 1888. The first practical investigations of the bending stress in the rail were apparently those made by the United States Government in 1894 by measuring the strains in the rail under the static load of the locomotive wheels. These were followed by Dr. P. H. Dudley's stremmatograph experiments for measuring the effect of dynamic loads. In the time elapsed since the publication of these investi- gations hardly anything has been done to further elucidate this problem. The sixth chapter deals with the detail of manufacture of the rail. The different stages in the process are described and the influence of each upon the finished product is pointed out. It would be outside the limits of the present iv PREFACE work to attempt a complete treatise on the manufacture of steel; the discussion concerns itself, therefore, chiefly with the practical results obtained rather than with theoretical considerations. In the last chapter are given Rail Specifications representing the best modern practice in this country and abroad. The forms recommended by the American Railway Engineering Association for reports and record of the rail are added for the sake of completeness in an appendix. The greater part of the bibliography of rail specifications given in article 39 was prepared for the present work by the Secretary of the American Soci- ety of Civil Engineers. The other shorter bibliographies appended to the discussions of several of the subjects were compiled by Mr. McClelland, Technology Librarian of the Carnegie Library of Pittsburgh. These, which are intended to supplement certain parts of the text, are not exhaustive but are thought to contain most of the important articles since 1906 which come within their scope. A bibliography for the years 1870-1906 with chronologi- cal arrangement appears in the Transactions of the American Institute of Mining Engineers, Vol. 37, pp. 617-627. A comprehensive bibliography of steel manufacture would be so extensive as to be unwieldy. Exhaustive bibliographies on this subject appear in the various volumes of the Journal of the Iron and Steel Institute, and a good selective bibliography of iron and steel manufacture appears in Bradley Stoughton's "Metallurgy of Iron and Steel." For the average reader who desires a more detailed discussion of the processes of manufacture of steel, Harbord's and Hall's excellent volume on the Metallurgy of Steel will gen- erally be found sufficient. It is believed that these references, together with the information contained in the footnotes throughout the book, will permit a thorough examination of any of the subjects to be made. The work is essentially a compilation. The author has, however, in every case endeavored to give credit where anything has been drawn from an outside source, and if he has been remiss in this respect it has been unintentional. In the discussion of the granular structure of steel he has been much indebted to the work of Mr. J. W. Mellor, from whose writings a considerable part of article 25 has been taken. The publications of the " Railway Age Gazette " have been freely quoted from and the author wishes to express his appreciation of the courteous permis- sion given for the use of this material and for the many quotations taken from other sources, especially those from articles which have appeared in the Proceed- ings of the American Railway Engineering Association. PREFACE v He has much pleasure in expressing his indebtedness to the following gentle- men who have given assistance in revising manuscript or proofs of the parts named : Professor Gaetano Lanza, mathematical discussions of Chapters II to V inclusive; Dr. A. B. Pierce, checking the author's calculations in these chapters; Professor W. F. M. Goss, wheel pressures; Dr. Hermann von Schrenk, forestry; Professor W. K. Hatt, strength of tie timber; Dr. P. H. Dudley, stremmatograph tests; Mr. Harry D. Tiemann, impact; Mr. James E. Howard, repeated stress; Mr. A. L. Colby, manufacture and specifications; Mr. Robert W. Hunt, influence of detail of manufacture; Mr. Bradley Stoughton, effect of temperature during rolling, and Mr. E. T. Howson for examination of the proofs before finally going to press. WILLIAM H. SELLEW. Detroit, Michigan, July, 1912. CONTENTS Chapter I. — Development op the Present Section p age 1. Early sections 1 2. Present sections 14 Chapter II. — Pressure of the Wheel on the Rail 3. Speeds of modern locomotives 21 4 Weights of modern locomotives 29 5. Effect of excess balance and angularity of main rod 35 6. Effect of irregularities in the track 45 7. Effect of rocking of the engine 49 8. Effect of flat spots in the wheels 54 9. Impact tests 62 10. The dynamic augment of the wheel load 69 11. Electric locomotives 74 12. Cars 81 Chapter III. — Supports of the Rail 13. The tie 90 14. Bearing of the rail on the tie 122 15. Fastening of the rail to the tie 138 16. Strength of the tie 153 17. Bearing on the ballast 179 18. Bearing on the subgrade 180 19. Supporting power of the tie 188 Chapter IV. — Stresses in the Rail 20. Stress at point of contact of the wheel with the rail 193 21. Proposed solutions of the bending stress in the rail 210 22. Tests to determine the bending stress in the rail 218 23. Calculation of the bending and shearing stress in the rail 239 24. Effect of the joint 259 Chapter V. — -Strength of the Rail 25. Influence of stress and strain on the strength of the rail 270 26. Effect of low temperatures on the strength of the rail 284 27. Physical tests of the strength of the rail '. . . 288 28. The strength of the rail and proper weight for various conditions of loading . 310 viii CONTENTS Chapter VI. — Influence of Detail of Manufacture p AGB 29. Chemical composition 326 30. Extraction of the iron from its ore 344 31 . Conversion of the steel 366 32. The Ingot 395 33. Influence of mechanical work 420 Chapter VII. — Rail Specifications 34. Comparison of American specifications 463 35. Specifications (New York Central Lines) for basic open-hearth rails 478 36. British standard specifications of bull head railway rails 484 37. British standard specifications of flat bottom railway rails 488 38. Specifications for street railway rails 491 39. Bibliography of rail specifications 494 Appendix Reports and records 501 Index 525 LIST OF ILLUSTRATIONS Fig. Page 1. Comparison of Rail Failures between Different Sections of Bessemer Steel Rails, from Oct. 31, 1908, to April 30, 1909 9 2. Increase in Axle Loads, 1885-1907 15 3. Classification of Locomotives 29 4. Progress in Locomotive Building 30 5. Decapod Locomotive of 1903 and American Type of 1857 31 6. Rail Pressures. Eight-wheel Engines 35 7. " " Ten-wheel Engines. (Light Weights.) 36 8. " " 442 (Atlantic) Type Engines 40 9. " " 462 (Pacific) Type Engines . . . , 41 10. " " 460 (Ten-wheel) Type Engines. (Heavy Weights.) 42 11. " " 260 (Mogul) Type Engines 43 12. " " 280 (Consolidation) Type Engines 44 13. Damaging Effect of Badly Balanced Locomotive , 39 14. Profile of Rail from Cuenot's Track Experiments 46 15. Rail Profile taken with a Railroad Automatic Track Inspector Machine 47 16. "Valley" or Local Depression in Track Profile 47 17. Summit between Two Depressions of Track Profile 47 18. Locomotive Driving Wheel Springs 48 19. Deflection of Locomotive Springs 49 20. Recording Device and Cab Controlling Mechanism for Testing Driving Wheel Springs 50 21. Recording Device in Place on Driving Wheel Spring 50 22. General Arrangement of Apparatus for Testing Driving Wheel Springs 51 23. Main Stylus used in Driving Wheel Spring Tests 51 24. Stress-strain Diagram. Locomotive Driving Wheel Springs 53 25. Flat Spot in Wheel 55 26. Irregularity in the Roundness of Present-day Chilled Car Wheels 58 27. Apparatus for Measuring the Effect of a Flat Spot 60 28. Diagram of Tests on Freight Car with Flat Wheels 61 29. Wire Tests 63 30. Deformation of Bridge Members under Passing Trains 64 31. Dynamic Wheel Loads of Typical Passenger Steam Locomotives 72 32. " " " " " Freight Steam Locomotives 73 33. Detroit River Tunnel Company's Locomotive 75 34. Pennsylvania" Electric Locomotive in Use in the New York Tunnels 76 35. Details Pennsylvania Electric Locomotive 77 36. Typical Load Diagrams for Electric Locomotives 78 37. Box Car 81 38. Flat Car 82 39. Gondola Car 82 40. Coke Car 83 41. Stock Car 83 42. Vestibuled Coach 83 43. Twelve-section Sleeping Car 84 44. Steel Combination Passenger and Baggage Car 84 45. Vestibuled Dining Car 84 LIST OF ILLUSTRATIONS e Car 84 47. Typical Load Diagrams for Cars 85 48. Typical Dynamic Load Diagrams for Motor Cars 85 49. 70-foot McKeen Motor Car 86 50. 70-foot General Electric Gas Electric Motor Car 86 51. Electric Railway Cars 87 52. Electric Railway Cars 88 53. Typical Load Diagrams for Electric Railway Cars 89 54. Carnegie Steel Tie : 90 55. Carnegie Steel Ties on the Bessemer and Lake Erie Railroad 91 56. Effect of Three Derailments on Steel Ties 91 57. Steel Tie after Four Years Service 92 58. Carnegie Steel Tie with Wedge Fastener 93 59. Hill Fastening on Carnegie Steel Tie 93 60. Hansen Steel Tie 94 61. Universal Metallic Tie on Pennsylvania Lines 95 62. Snyder Steel Tie 95 63. Buhrer Combined Steel and Wood Tie on L. S. and M. S. Ry 96 64. Mexican Railway Steel Tie 97 65. Buhrer Concrete Tie 98 66. Bottom Surface of Buhrer Concrete Tie 99 67. Section of Track on Chicago and Alton R.R., showing Kimball Tie 99 68. Kimball Tie put in Track on N. Y. C. &. St. L. R.R., July, 1904 100 69. Kimball Tie, showing Spiking Plugs 100 70. Percival Concrete Tie 101 71. Sarada Tie 102 72. Adriatic Railway Tie 102 73. Riegler Concrete Tie 103 74. " " " Appearance in the Track 103 75. Forest Regions of the United States 107 76. Hunnewell Plantation 109 77. Farlington Forest 110 78. Standard Prussian Ties of Baltic Pine 117 79. Standard Oak and Beech Ties on the French Eastern Railway 117 80. Distribution of Pressure from Tie Plate 118 81. Half Round Tie Proposed by the Forest Service 118 82. Spacing of Half-round Ties 118 83. Pole Tie . . 119 84. Extreme Form of Half-round Tie 120 85. Test on McKee Tie Plate 122 86. Wear of Tie under Tie Plate 123 87. Loblolly Pine Tie. Section of Tie under Rail Bearing 124 88. " " " Section from Middle 124 89. Belgian State Railways, 105-pound Rail and Tie Plate 125 90. " " " 115-pound Rail and Tie Plate 126 91. Kingdom of Wurttemberg State Railways, Tie Plate 127 92. Bavarian State Railways, Joint Hook Plate 128 93. Kingdom of Saxony State Railroad, Joint Hook Plate 129 94. Elsass-Lothringen State Railways, Tie Plate 130 95. Prussian State Railways, Tie Plate 131 96. Bavarian State Railways, Intermediate Wedge Plate 132 97. Wooden Tie Plate on French Eastern 132 98. Plain Bearing Plates, German Experiments on Tie Plates 134 99. Hook Plates, German Experiments on Tie Plates 135 100. Hook Plates with Clips, German ExDeriments on Tie Plates 135 101. Group 1, German Experiments on Tie Plates 136 LIST OF ILLUSTRATIONS xi Fig. Page 102. Group 2, German Experiments on Tie Plates 136 103. Group 3, German Experiments on Tie Plates 137 104. Short Leaf Pine Tie, after 2 Years' Service, cut through Spike Holes 138 105. Cross Section through the Spike Holes of Short Leaf Pine Tie 139 106. Common Spike 140 107. Common Screw Spike 140 108. Screw Spike used by Grand Duchy of Baden State Railways 140 109. Early French Screw Spikes 141 110. Machine Preparing Ties for Screw Spikes 142 111. Showing Application of Screw Spikes on A. T. & S. Fe R.R 142 112. French Railways — Rail Fastenings 143 113. German Railways — Rail Fastenings 145 114. English and Scotch Railways — Rail Fastenings 146 115. Screw Spike deduced from European Practice 147 116. French Screw Spike 149 117. Wooden Tie Plug used on French Railways 149 118. Collet Trenail 150 119. Cross Section of Pine Tie through Dowel 151 120. Three Ties of Baltic Pine on the Prussian State Railways 151 121. Comparative Resistance to Vertical Pressure of Screw Spikes in Pine Ties 152 122. " " " " " " " " " Beech Ties 152 123. Control Plan — Creosote Tie Tests 161 124. Tie Plate Forms used in Tests at Purdue University 170 125. Elastic Curve of Tie, 7 feet 10.4 inches long 172 126. " " " " 8 feet 10.3 inches long 172 127. Wood and Composite Ties used in Cuenot's Experiments 173 128. Measuring Apparatus for Ties under Static Load 174 129. " " " " " Dynamic Load 175 130. Results of M. Cuenot's Tests on Ties 176 131. Strain Diagram of Entire Tie 177 132. " " " Tie between Rails 178 133. " " " Tie outside of Rails 178 134. Ballast Experiments — Schubert. Six inches of sand and 6 inches of gravel 181 135. " " " Six inches of sand and 6 inches of stone 181 136. " " " Stone with thin layer of sand 182 137. " " " Stone resting on clay subgrade 182 138. Effect of Overloading the Subgrade 183 139. Pennsylvania Track Testing Apparatus 1 183 140. Distribution of Pressure to Subgrade 186 141. Bell's Apparatus for Measuring Depression of the Track 191 142. Reaction of Tie 191 143. Compression Modulus — Condition of Free Flow 193 144. " - " Partially Restricted Flow 193 145. " " Restricted Flow 193 146. Area of Contact between Wheel and Rail 195 147. Relation between Areas of Contact and Load on Wheel 196 148. Tire Wear, Ten-wheel Engines 198 149. " " Eight-wheel Engines 199 150. Two Pieces of a Worn 100-pound Rail after Testing 204 151. Reciprocating Machine for Testing Flow of Metal in Head of Rail 206 152. Section of 70-lb. Bessemer Rail Tested for Flow of Head 207 153. D : stribution of Tie Pressure under Rail 213 154. "Class I" Engine with 75 per cent Impact 214 155. Track Depression under "Class I" Loading 214 156. " Class K" Engine with 75 per cent Impact 215 157. Track Depression under " Class K" Loading 216 xii LIST OF ILLUSTRATIONS Fig. Page 158. Bending Moment of Rail placed on Ties 218 159. Railroad Track Experiments, Boston and Albany R.R 219 160. " " " Photograph of Leveling Instrument for Measuring the Depres- sion of the Track 220 161. " " " Photograph of Micrometer for Determining the Fibre Stress in the Base of the Rail 220 162. " " " C.B.&Q.R.R 222 163. Advance Wave Determinations 223 164. Movement of Rails Laid Alongside of Track 224 165. Railroad Track Experiments, View showing Micrometer for Measuring Strains in Rails, in Position on Base of Rail under Driving Wheel 226 166. " " Pennsylvania R.R. Depression in Ballast 234 167. " " " " " Stress in Rail 235 168. Stremmatograph Tests at 19 and 40 m.p.h 236 169. " " " Slow Speeds 237 170. Wheel Loads for Different Spacing of Drivers 240 171. Rail Diagram for Wheel Spacing of 60 Inches 242 172. " " " " " " 70, 80 and 90 Inches 245 173. Distribution of Llorizontal Stress in Rail 248 174. Shearing Stress of Point Distant y' from Neutral Axis 249 175. Shearing Stress in 100-pound A. S. C. E. Rail 250 176. Lines of Principal Stress in Beam 251 177. Diagram of Pieces tested for Sag of Rail Head and Bending of Web 254 178. Method of Stationary Tests for Sag of Rail Head and Bending of Web 254 179. Sag of Rail Head in Stationary Tests 255 180. " " " " " Rolling Tests 257 181. Rails after Rolling Test with Load of 90,000 Pounds 258 182. Shearing Stress in 100-pound A. S. C. E. Rail and Splice Ear 262 183. 100 per cent Joint 263 184. Joint showing Uneconomical Distribution of Metal 263 185. " " Economical Distribution of Metcl 263 186. Diagram of Watertown Arsenal Tests on 100-pound Joints 265 187. Pure Swedish Iron 270 188. Pure Copper 270 189. Copper-bismuth Alloy 271 190. Iron with 1.8 per cent Carbon 271 191. Cleavage Planes with Crystals arranged Symmetrically 273 192. " " " " " in an Irregular Manner 273 193. Iron Strained beyond the Elastic Limit 273 194. Lead Strained beyond the Elastic Limit 273 195. Cross Section of Unstrained Metal 274 196. Cross Section of Metal after being Stressed 274 197. Slip Bands 275 198. Polished Surface with Small Cracks 275 199. " " " Large Cracks 276 200. Behavior of 0.55 Carbon Steel under Repeated Alternate Stresses 279 201. Behavior of 0.82 Carbon Steel under Repeated Alternate Stresses 279 202. Comparison of the Behavior of Different Grades of Steel under Repeated Alternate Stresses 281 203. Number of Repetitions before Rupture in Endurance Tests of Materials 283 204. Standard Drop Testing Machine 290 205. Diagram of Tests with Drop Testing Machines of Old and New Design 291 206. Relation of Work Done in Bending Rail in Drop and Static Tests 294 207. Time-deflection Curve, Massless Beam, within the Elastic Limit 296 208. " " Beam Stressed beyond the Elastic Limit 298 209. Scleroscope 298 210. Scleroscope Tests on Open-hearth Rail 299 LIST OF ILLUSTRATIONS xiii Fig. Page 211. Scleroscope Tests on Bessemer Rail 299 212. " " " New Titanium Rail 300 213. Amsler-Laffon Instrument for Measuring Hardness 301 214. Machine for Testing Rail Wear at Pennsylvania Steel Company 304 215. Diagram of Round Test Pieces; Tensile Tests on Rail Steel 304 216. Diagram of Flat Test Pieces; Tensile Tests on Rail Steel 308 217. Location and Numbers of Test Pieces used in Waterhouse's Tests 309 218. Effect of Repeated Loads on Beams 311 219. Resistance of Sub-grade to Pressure of the Track 314 220. Prices of Iron and Bessemer Steel Rails, 1855-1910 325 221. Comparative Wear of Rails of Similar Chemical Composition 327 222. Tenacity of Iron-Carbon Alloys 329 223. Influence of the Proportion of Nickel and Varying Heat-Treatment upon the Tensile Strength of Nickel Steel 336 224. Influence of the Proportion of Nickel and Varying Heat-Treatment upon the Ductility of Nickel Steel 337 225. Influence of the Proportion of Manganese on the Tensile Strength of Manganese Steel .... 337 226. Influence of the Proportion of Manganese on the Ductility of Manganese Steel 338 227. Tensile Strength and Ductility of Carbon Steel and of Manganese Steel 339 228. Elasticity and Ductility of Carbon Steel and of Manganese Steel 340 229. Ore Roasters, Norway Furnace, 1883 345 230. Open Pit Mine on Mesaba Range, Mountain Iron Mine, near Hibbing, Minnesota 346 231. View of the West Cut, looking North, Biwabik Mine 347 232. Steel Ore Dock at Two Harbors, Minn 348 233. Steamer " Augustus B. Wolvin " 349 234. Great Northern Railway Ore Dock at Allouez Bay, Superior, Wis 350 235. The "Wolvin"; a Typical Lake Steamer for the Transportation of Ore 351 236. Ten-ton Bucket of Unloader in Hold of the "Wolvin" 352 237. General View of Ore Unloader with Steamer at the Dock 352 238. Brown Hoist Unloader Unloading Cargo of Ore 353 239. Blast Furnace with Stoves and Buildings 354 240. Ground Plan, Showing the General Arrangement of Blast Furnace No. 4, Built at the Hazelton Plant of the Republic Iron and Steel Co 355 241. Sectional View of Hazelton Blast Furnace No. 4 356 242. Top Rigging of Blast Furnace 357 243. The 450-ton Furnaces, Hot Stoves, and Gas-cleaning Plant in Course of Erection at Gary. . 358 244. The Whitwell Hot-blast Stove 359 245. Julian Kennedy Stove 360 246. Isabella Furnace, Carnegie Steel Company 361 247. Operation of Isabella Furnace on Dry Blast 362 248. 300-ton Mixer 364 249. Ten-foot Iron Cupola, Maryland Steel Company 365 250. Early Experiments of Blowing Air through Bath 367 251. Bessemer SteeL Works, Johnstown, Pa 368 252. American 5-ton Bessemer Plant. Plan 369 253. " " " " Section 369 254. Arrangement of Converters at Maryland Steel Company 369 255. 18-ton Converter, Maryland Steel Company 370 256. Typical 16-ton Bessemer Converter 371 257. Charging Bessemer Converter 372 258. Bessemer Converter in Full Blast 373 259. Modern Open-hearth Furnace 376 260. Open-hearth Plant 377 261. Wellman Tilting Open-hearth Furnace 378 262. Pouring Steel into Ladle at Open-hearth Furnace 379 263. Charging Platform of the Open-hearth Furnaces at Gary 381 xiv LIST OF ILLUSTRATIONS FlG - Page 264. Heroult Electric Furnace 384 265. Stassano Electric Furnace 385 266. Roechling-Rodenhauser Furnace 386 267. Details of Casting Ladle 389 268. Crushed Head 39-2 269. Crushed Head 394 270. Teeming Ingots at Bessemer Converter 395 271. " " " Open-hearth Furnace 396 272. Stripping the Mold from Ingots 397 273. Soaking Pits — Gary 397 274. Soaking Pits 398 275. Formation of Pipe in Ingot 399 276. Section of Ingot, containing Cavity of 128 cubic inches 400 277. Bloom from an Ingot of Same Heat and of Same Size as Fig. 276, showing Reduction of Cavity 400 278. Structure A. — Brinell's Tests 403 279. " B. — Brinell's Tests 403 280. " C. — Brinell's Tests 403 281. " D. — Brinell's Tests 403 282. " E. — Brinell's Tests 403 283. " O. — Brinell's Tests 403 284. " H. — Brinell's Tests 403 285. Ordinary Steel Ingot and Titanium Steel Ingot 406 286. Sulphur in Ordinary Steel 407 287. " " Titanium Steel 407 288. Phosphorus in Ordinary Steel 408 289. " " Titanium Steel 408 290. Carbon in Ordinary Steel 409 291. " " Titanium Steel 409 292. Influence of Conditions of Casting as shown by Wax Ingots. (Figs. 1-6.) 412 293. " " " " " " " " " " (Figs. 7-13.) 413 294. Illingworth's Press for Compressing Steel Ingots 414 295. Williams' Abdominal Liquid Compression of Solidifying Steel Ingots 414 296. Whitworth's Hydraulic Press for the Compression of Steel Ingots 415 297. Harmet's Liquid Compression by Wire Drawing 416 298. Steel Entering the Rolls 421 299. Cross Section of 8 by 8-inch Rail Bloom 422 300. Rail from Early Pass in Roughing Rolls .♦ 422 301. Same Rail as shown in Fig. 300 after Further Reduction 423 302. Finished Raii from Same Ingot as Bloom and Pieces from Roughing Rolls 423 303. Cooling Curve of Solid Copper 425 304. Cooling Curve of Water 425 305. Recalescence 425 306. Cooling Curve of Iron 426 307. Cooling and Heating Curves of Steel 426 308. Cooling of "Solid Steel" 427 309. The Influence of the Finishing Temperature on the Size of Grain 428 310. Influence of Finishing Temperature on the Size of Grain of Steel of 0.50 per cent Carbon . . . 429 311. Diagram of Results of Experiments on Rolling at Different Temperatures 430 312. Rail "B" near Surface 431 313. " "A" near Surface 431 314. " "B" Center of Head 431 315. " "A" Center of Head 431 316. Top View at Top of Head, 70-lb. Rail 432 317. " " " Center of Head, 70-lb. Rail ". 432 318. Side View at Top of Head, 70-lb. Rail 432 319. " " " Center of Head, 70-lb. Rail 432 LIST OF ILLUSTRATIONS xv Fig, Page 320. Transverse View at Top of Head, 70-lb. Rail 433 321. " " " Center of Head, 70-lb. Rail 433 322. Pieces for Microscopic Views shown in Figs. 316-321 433 323. Rail Mill, Algoma Steel Company 439 324. Housing for 28-inch Three-high Mill 440 325. Rolls used in Three-high Rail Mills 440 326. Three-high Rolls in the Rail Mill at Gary 441 327. Pass Diagram, Rail Mill, Illinois Steel Company, South Works 442 328. Rail Mill, Illinois Steel Company, South Works 443 329. Saw Runs of American Rail Mills 445 330. Head Sweep * 445 331. Cold Straightening Press, Maryland Steel Company 446 332. Value of V/E for Tables XCVI, XCVII and XCVIII 447 333. Diagram of Cogging Rolls, Tables XCVI, XCVII and XCVIII 448 334. Bar Sections of Passes 14-23 (Tables XCVI, XCVII and XCVIII) 449 335. Sections in which only "Direct Pressure" occurs in the Process of Rolling 456 336. Illustration of "Indirect Pressure" 456 337. Effect of Inclination of Inner Surface of the Rail Flange on Energy required in Rolling. . . . 457 338. Work done in Accelerating the Rotating Masses in Reversing Mill 459 339. Recent Rail Sections 460 340. Shrinkage Allowed in American Specifications in 1909 475 341. Test Pieces C and D, British Standard Specifications of Rails 487 342. M. W. 401. — Report of Chemical and Physical Examination 503 343. M. W. 402. — Certificate of Inspection 504 344. M. W. 403. — Report of Shipment 505 345. M. W. 404. — Report of Rail Failures in Main Tracks 506 346. M. W. 405. — Superintendent's Monthly Report of Rail Failures in Main Tracks 508 347. M. W. 406. — Annual Statement of Steel Rails Existing in Main Tracks 510 348. M. W. 407. — Laboratory Examination of Special Rails 511 349. Standard Locations of Borings for Chemical Analyses and Standard Tensile Test Pieces. . . . 512 350. M. W. 408. — Summary of Steel-rail Failures for One Year Compared with the Same Period of Previous Year 513 351. M. W. 409. — Summary of Steel-rail Failures for a Period of Years 514 352. M. W. 410. — Comparative Number of Failures of Steel Rails of Different Section or Pattern, Rolled by Different Steel Companies 515 353. M. W. 411. — Position in Ingot of Steel Rails which Failed 516 354. M. W. 412. — Cover Page for Forms M. W. 408, 409, 410 and 411 517 355. M. W. 413. — Location Diagram One inch equals one mile 518 356. M. W. 414. — " " Two inches equal one mile 519 357. M. W. 415. — Diagram showing Lines of Wear 520 358. M. W. 416. — Record'of Comparative Wear of Special Rail 521 359. M. W. 417. — Cover Page for Forms M. W. 413, 414, 415 and 416 522 360. Defective Rail Sheet 523 361. Diagram of Rail Failures, Harriman Lines 524 LIST OF PLATES (All plates except V and VI are in the back of the book.) (Plates V and VI are between pages 11 and 12.) - I. Standard Rail Sections of the American Society of Civil Engineers. II. Rail Sections used before the Adoption of the A. S. C. E. Standard Sections in 1893. III. Standard Wheel Sections showing Coning of Wheel. IV. Rail Sections used during the Period between the Adoption of the A. S. C. E. Standard Sections in 1893 and the Recommendation of the New Standard Sections by the American Railway Association in 1907. V. Examples of Defective Rails; Broken Rails, Flow of Metal and Crushed Head. VI. " " " " Split Head, Split Web and Broken Base. ~VII. Proposed Standard Rail Section of the American Railway Association, Series "A." VIII. " " " " " " " " " Series "B." - IX. Standard "P.S." Rail Section of the Pennsylvania Railroad System. " X. Rail Sections of the Vignole Type. " XL Rail Sections used on German Railways. ~XII. Midland Railway, Permanent Way. "XIII. L. & N. W. R. Details of Permanent Way. ~XIV. British Standard Bull Head Railway Rails. "XV. " " Flat Bottom Railway Rails. -XVI. Rail Sections for Street Railways, Tram Girder Rails and High Tee Rails. XVII. " " " " " Standard Girder Sections of the American Electric Railway Engineering Association. 1 XVIII. British Standard Tramway Rails. XIX. Deflection of Driving Wheel Spring, Consolidation Engine No. 1064, Boston & Maine Railroad. XX. Passenger Locomotive Diagrams. " XXI. Freight Locomotive Diagrams. XXII. Examples of American Tie Plates. XXIII. Rail Diagram of Love. XXIV. Examples of American Rail Joints. XXV. Joints Tested at the Watertown Arsenal. XXVI. Dynamic Wheel Loads for Various Rails and Axle Spacing. XXVII. Bending Moments in Different Weights of Rail Corresponding to Loading on Plate XXVI. XXVIII. Weight of Rail for Various Conditions of Loading and Classes of Track. XXIX. Plan of Gary Steel Plant. XXX. Reversing Cogging Mill. XXXI. American Three-high Mill, with 36-inch Rolls. XXXII. Power required to Roll Rails about 35.5 kg. per meter. XXXIII. Form M. W. 418, Am. Ry. Eng. Assn. STEEL RAILS CHAPTER I DEVELOPMENT OF THE PRESENT SECTION 1. Early Sections Apparently the use of steel rails was first resorted to on account of the poor quality of the iron rails of later manufacture. The wear of these iron rails took the form of crushing or lamination, which destroyed the running surface of the rail and rendered it unfit for use. An iron rail when manufactured, even in the best way, was little more than a bundle of rods; and the top slab under the heavy pounding of the locomotive had a tendency to spread side- ways and become laminated. A steel rail, on the contrary, was rolled from a solid ingot and for that reason was much more durable.* Iron, in the matter of wear, exhibited very great irregularity, some rails showing signs of distress within a year or two of being laid down, while others afforded very satis- factory results. f As an illustration of the latter assertion we can instance the experience on the main line of the North-Eastern Railway on certain sections of its system which may be taken as fair samples of the others. On that extending between Newcastle and Berwick, 66.8 miles of double way, the iron rails laid down in 1847 weighed 65 pounds per yard. Renewals commenced in 1855 and terminated in 1867. In these the weight was increased to 82 pounds per yard. The maxi- mum duration of the 65-pound rails was 21 years and the minimum 8 years, the average being 12.8 years. Mr. T. E. Harrison stated in 1867 that on 700 miles of permanent way of the North-Eastern Railway the average duration of the last complete set of rails was found to be about 15.5 years; and some which were laid down in 1834 were still in use. * See The Manufacture and Wear of Rails by C. P. Sandberg, Minutes of Proceedings of the Institution of Civil Engineers, Vol. XXVII, Session 1867-8, and R. Price Williams's Paper "on the Maintenance of Permanent Way," ibid., Vol. XXV, p. 353. t Principles of the Manufacture of Iron and Steel. I. Lowthian Bell. London, 1884. 2 STEEL RAILS The statements just submitted do not afford any proper criterion of the resisting powers of iron rails; for this can only be determined by the comparative weights of the engines, the amount of traffic, and the speed of the trains which have passed over them. According to Mr. R. Price Williams the average life of an iron rail, on the most heavily worked portions of the railways in the United Kingdom in the year 1878, may roundly be taken at about 17| millions of tons. There is nothing speculative in the assertion that iron rails made before the complete discontinuance of refining were, generally speaking, longer lived than those of later manufacture. No doubt in the later days of iron rails the permanent way was much more severely taxed than was formerly the case. The engines were more ponderous, the traffic was heavier, and the speed greater; but the experience of the North-Eastern Railway at all events indicates that rails of iron have occasionally been made to give very satisfactory results. Whether this be due to their having been made from refined metal, or whether indeed they were so made, we have unfortunately little means of proving. It is significant to note that during the twenty years preceding 1868 the price of iron rails had been gradually reduced to one-third of their original cost, and that this reduction was accompanied by the production of an inferior quality of rail. * In America several of the railway companies began to use steel rails as far back as 1864. In that year the Chicago and Northwestern, the Phila- delphia, Wilmington and Baltimore, and the Old Colony and Newport each laid portions of track with this metal. In the following year the Boston and Albany, the Boston and Providence, the Connecticut River Railroad, the Chicago, Rock Island and Pacific, and the Chicago and Alton each began the use of steel. In September, 1869, a commission appointed to ascertain the extent to which steel rails had been tried in the United States ascertained that of fifty- seven railways then in operation, from which reports had been obtained, twenty- six had made use of steel in weights varying from 100 to 15,000 tons, the whole bulk reported as in use being 49,800 tons, equal to about 518 miles of tracks. This, however, did not by any means represent the total weight of steel rails laid throughout the States. The Commission already referred to was, indeed, particular in calling attention to the fact that on the first of January, 1870, there were at least 100,000 tons of steel rails laid down in America, and 10,000 tons of steel-headed rails besides. Of this quantity the largest bulk had been supplied by England, and almost entirely by the Atlas, Barrow and Dowlais Works, although several thousand tons had been contributed by three estab- lishments in Germany. * Steel — Its History, Manufacture, Properties, and Uses. J. S. Jeans. London, 1880. DEVELOPMENT OF THE PRESENT SECTION 3 In France the Paris, Lyons, and Mediterranean Railway Company decided, so early as 1867, to use only steel rails in relaying its permanent way on 860 kilometers of the Paris and Marseilles line, where more than 10,000 trains ran over each line of way yearly, at speeds which might reach 90 kilometers per hour. In Austria steel rails were used as early as 1859 on the Northern Railway, connecting Vienna with Cracow. They were, however, of puddled steel, manu- factured at the works of the Archduke Albrecht, at Carlshutte. In 1861 one German mile (about 4.8 miles) of the main line was laid with steel rails by way of experiment. So much satisfaction was afforded by this trial that in 1865 it was resolved to reconstruct in steel the whole of the main- line permanent way, and by the close of that year thirty-five English miles had been laid. Previous to this, however, steel had been largely used in Austria for railway crossings — so much so, indeed, that at the close of 1864 there were, on the Northern line, 468 steel crossings as compared with 977 of iron. In Russia several lots of steel rails were laid down previous to 1872, but the use of that metal cannot be said to have received a thorough impulse until, in the year named, the Russian Imperial Administration approved the con- struction with steel rails of the railways from Wjasma to Tula, Rjask, and Jetetz, and from Morschunsk to Siezran, a total length of 1200 kilometers. Previous to this time steel rails had been laid experimentally on the Nicolas Railway, where they were found to answer so well that in 1872 about 70,000 tons of steel rails were ordered for Russia, chiefly from Creusot. In England, before the end of 1861, steel rails had been laid down on the Caledonian, Lancashire and Yorkshire, London, Brighton and South Coast, and Rhymney railways, as well as on the London and North-Western. The first Bessemer steel rails made in America were rolled at the North Chicago Rolling Mill on the 24th of May, 1865, from hammered blooms made at the Wyandotte Rolling Mill from ingots of steel made at experimental Steel Works at Wyandotte, Mich. The experimental Steel Works at Wyandotte were erected in 1864, and were the first works started in the country for conduct- ing the pneumatic or Bessemer process. The rolls upon which the blooms were rolled at the North Chicago Rolling Mill were those which had been in use for rolling iron rails, and, though the reduction was much too rapid for steel, the rails came out sound and well shaped. The first steel rails rolled in the United States upon order, in the way of regular business, were rolled by the Cambria Iron Company at Johnstown, Pa., in August, 1867,* from ingots made at the * See paper on the Development of the American Rail and Track by J. Elfreth Watkins, Trans. Am. Soc. of Civil Engrs., April, 1890, Vol. XXII, p. 228. 4 STEEL RAILS works of the Pennsylvania Steel Company, at Harrisburg, Pa., rails were rolled by the Spuyten Duyvil Rolling Mill Company, at Spuyten Duyvil, N. Y., early in September of that year, from ingots made at the Bessemer Steel Works, at Troy, N. Y., then owned by Winslow and Griswold, but these were on experimental orders, and not regular ones from any railway company.* Before, however, the American steel works had produced any Bessemer rails, or, indeed, before any such works had been executed in this country, the Pennsylvania Railway Company had imported from England a lot of about 150 tons. This was towards the close of the year 1863. Some little delay took place in slotting the rails to receive the track fastenings ; they were not laid down until the early part of 1866, when they were placed on sidings in the yards at Altoona and Pittsburg, where they would be subjected to considerable use. As the rails appeared very brittle, it was not deemed expedient to place them in the main track where they would be passed over by trains at high rates of speed. None of them, however, were broken in the track, and as they exhibited little or no appearance of wear, other steel rails were ordered in 1867, of a quality combining more toughness with a sufficient degree of hardness, and experiments were continued to test the relativ3 merits of the several descriptions of rail. About 1864 the Erie Railway Company ordered from John Brown and Company, of Sheffield, England, 1000 tons of Bessemer steel rails at 25£ per ton. The American Commission of 1869 concluded, as the result of comparing reports obtained from twenty-six railways then using steel rails: (1) That ex- tremes of temperature do not injuriously affect steel rails. The Grand Trunk Railway reports them as not injured by a temperature of 30 degrees below zero of Fahrenheit, and no other road appears to find them unable to stand a cold winter. (2) That the durability of steel rails far exceeds that of the best iron rails. The Erie Railway reports their steel rails as having outworn thirteen sets of iron rails, and as showing scarcely any sign of wear. The Philadelphia, Wilmington and Baltimore reports them as having outworn seventeen iron rails, and as showing little wear. The Chicago and Northwestern say that steel rails have outworn fifteen iron rails, and show no perceptible wear. In 1874 a small committee of American experts f conducted a very careful and elaborate inquiry into the form, endurance, and manufacture of rails. In * Private communication from Mr. Robt. W. Hunt. t Appointed January 8, 1873, by the American Society of Civil Engineers, to determine " the best form of standard rail sections of the United States; the proportion which the weight of rails should bear to the maximum loads carried on a single pair of wheels of locomotives or cars; the best methods of manufacturing and testing rails; the endurance, or, as it is called, the ' life ' of rails; the causes of the breaking of rails and the most effective way of preventing it, and the experience of railways in America DEVELOPMENT OF THE PRESENT SECTION 5 speaking of the comparative value of steel and iron rails this committee stated, that "while steel rails as we get them are tolerably uniform in quality, iron varies so much that no comparison can be made except of particular qualities or of averages of qualities widely different. We can as yet do little more than give the results of our own experience. In so doing we shall not only compare steel and iron, but also the effects of some different circumstances on the duration of both. It seems probable that the best iron, if homogeneous and the head of uniform hardness, so as to wear off evenly like steel, would, with machinery of moderate weight, wear a third or even half as long as steel. The chairman has found that his 62-pound iron rail, after carrying about 14,000,000 tons gross load, has worn off only about 25 per cent more than the steel rails on the same track and under the same circumstances. Probably it will not wear so well when the top crust is worn through. But owing to want of homogeneousness and uniformity the iron scales, splinters, laminates, or somehow disintegrates or mashes in spots before it wears out." Ashbel Welsh, the chairman of this committee, subsequently presented a final report, giving particulars of the behavior of the steel rails, 53 pounds per yard. Believing that a very thin stem and a very thin base would possess sufficient strength, he designed a pattern in which as much metal as possible should be placed in the head, and as little as possible anywhere else. The height was 4 inches, the width of base 4 inches, the head fully 2f inches wide and 1} inches deep; radius of sectional curvature of the head 12 inches, stem T 7 ? inch thick, base f\ inch thick at the edges; angle of base and of under sides of head 14 degrees, length of rails 30 feet, weight 53 pounds per yard. The rails were rolled by John Brown and Company, and were laid in 1867 and 1868 at places exposed to very heavy traffic, on the railway between Phila- delphia and New York, where iron rails had lasted only four months. In straight portions of the line, after having carried a gross weight of about 50,000,000 tons, mostly at high speeds, the heads had been worn down \ inch, having lost in weight about 6 pounds per yard. In some sharp curves the sides of the heads were so much worn that the rails were taken up in June, 1876. The early steel rails were naturally made to the existing iron pattern. These were generally pear-headed in order to prevent the side of the head from breaking down, and were therefore not adapted to fishing. In 1866, as we have seen, Mr. Ashbel Welsh designed a section differing but slightly from the in the use of steel rails." See paper on the Form, Weight, Manufacture and Life of Rails. A Report by Ashbel Welsh, C. E.; M. N. Forney, M. E.; O. Chanute, C. E.; and I. M. St. John, C. E. Trans. Am. Soc. of Civil Engrs., Vol. Ill, p. 87. 6 STEEL RAILS modern rail,* and in 1874 Mr. Chanute, chief engineer of the Erie Railway, investigated to determine the proper contour of the head by observing the contour of the rails worn down by the action of the wheels. The width and shape of the head having been provided for, the rail was considered as a beam, and as much metal as possible was taken from the web and flange to deepen it. With the older sections the connections at the joints were very unsatis- factory, the design preventing the fishplate from supporting the head. If the plate could bear against horizontal surfaces, it would not be forced out laterally by the loads, but the rail could not be properly filled by rolling and the play would rapidly increase and could not be taken up. Mr. Chanute experimented to determine the correct angle of the under side of the head to hold the fishplate and found that with an angle above 15 degrees the plate was loosened by stretching of the bolts. This relieved the pressure and friction of the plate against the nuts and allowed them to turn. He therefore adopted the angle of 15 degrees under the head, and to avoid unnecessary metal in the flange he made its angle 12 degrees. The adoption of an improved section was very slow, and as late as 1881 119 patterns of steel rails of 27 different weights per yard were regularly manu- factured, and 180 older patterns were still in, use, making a total of nearly 300 different patterns. This great variety of sections in use required the mills to keep a large number of different rolls in stock, and finally to standardize the design of the rail the present A. S. C. E. section, shown in Plate I, was presented to the society on August 2, 1893. These sections met with favor, and were adopted by many railroads, so that in a few years about two-thirds of the output of the rail mills conformed to this design. The gradual evolution of the present design of rail is shown in Plate II. The earlier rails show the pear shape of the old iron rails, followed by the rails where the section was more adapted to fishing and having a better distribution of the metal to afford a stiffer rail. The question of cylindrical tires and flat top rails was one on which there existed for a long time a great deal of difference of opinion among railroad engi- neers. In the early days of railroading the wheels were generally coned to a ratio of 1 in 20, and after the organization of the Master Car Builders' Association this ratio was adopted as the standard. This particular ratio apparently grew out of * Robert L. Stevens in 1830 designed a " T " section of iron rail for the Camden and Amboy Railroad, and is generally considered to have been the inventor of the flat-footed rail. See Trans. Am. Soc. of Civil Engrs., Vol. IV, p. 236, and ibid., Vol. XXII, pp. 209, 216. DEVELOPMENT OF THE PRESENT SECTION 7 the prevailing practice at the car wheel foundries, and not from any theoretical consideration of the relation of the wheel to a curve. The agitation for the cylindrical wheel grew out of efforts to measure the area of contact between the wheel and the rail, to determine the intensity of pressure on the metal, and led the Master Car Builders' Association, in 1886, to change their standard wheel section and reduce the coning ratio from 1 in 20 to 1 in 38, which was about the last draft that would allow free withdrawal from the mold. This section is shown on Plate III which also shows the cylindrical wheels considered by the Association at this period. The section thus recommended and adopted by the Association passed into general use on the railways of the country. It was noticed, however, that the change was followed by a large increase in the number of broken and sharp flanges, and after using the section for over twenty years it was restored to the former ratio of 1 in 20 as shown by the 1910 wheel given on the plate. The rails of heavier section manufactured within the last few years are not giving the service that should be expected of them. The fault may lie in im- proper methods of manufacture or in the design of the rail itself, which, while suitable for the conditions existing nineteen years ago, may be unfitted for the heavy wheel loads of to-day. It has been claimed that the old committee of the American Society of Civil Engineers did not properly appreciate the importance of low finishing temperature in designing their rails, and that the sections recommended in its report in 1893 do not permit of a low enough finishing temperature in rolling owing to the wide, thin flanges. As a matter of fact this was one of the points which received most careful consideration, not only by discussion between the members of the committee, but also in consultation with rail manufacturers. But a peculiarity of the situation comes from the fact, that at that time, what we now consider sections of necessary weight were then not in general use. The committee was in- structed to devise sections from 100 pounds per yard down, decreasing by 5 pounds, but 80-pound sections were then regarded as the heaviest likely to be extensively used. Only one railroad at that time had heavier sections, and that was the Philadelphia and Reading, which had a few 90-pound rails in use. The New York Central had put in 80-pound rails, and perhaps they had a few heavier ones, but their standard was 80-pound. The Delaware and Hudson had adopted the 80-pound rail, also the Michigan Central. The question was to devise a section which the committee considered a good one and which could be easily rolled. 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It has been the invariable experience in changing from a light to a heavy section, in any class of rolled steel, that difficulties have been met and modifi- cations have been made in the methods of rolling, in order to get as good structure in the heavier sections as was formerly obtained in the lighter sections. In ordinary sections other than rails it was a comparatively easy matter to over- come the trouble and get a good structure; but the thin flange of the rail, and the higher carbons called for in the heavier sections, further complicated matters. The greatest need at this time is for reliable statistical information taken from properly kept records. The Committee on Rail of the American Railway Engineering Association have been engaged for several years in collecting statistics of defective rails on American roads. The classification adopted by the committee is as follows: 1. Broken Rail. 2. Damaged. 3. Flow of Metal. 4. Crushed Head. 5. Split Head. 6. Split Web. 7. Broken Base. It is the intention of the classification that all rails which broke in service, or which have a straight crack working from top to bottom or from bottom to top, which would very quickly result in a broken rail, should be classified as "broken rails," regardless of internal defects. All of the other defective rails which are removed, not being "broken" or damaged on account of wrecks, broken wheels or similar causes, are to be classified under one of the other heads, from 3 to 7, both inclusive. Fig. 1 shows a comparison of rail failures between different sections. (See Plates I, IV, VII and IX for description of sections.) The most striking char- acteristic of the diagram is the comparatively large number of head failures of 85 N, 85, both on tangent, 36.1 failures per 10,000 tons, and on curve 27.7 failures per 10,000 tons laid. The legend on the diagram explains that this is a Chicago, Burlington and Quincy section. It can hardly be said that the carbon is excessively high, although pretty high, unless it is badly segregated, the chem- ical constituents being: DEVELOPMENT OF THE PRESENT SECTION 11 Carbon 48 to .58 Phosphorus 10 Manganese 80 to 1.10 Silicon 20 Section 852, 85-pound, also a Chicago, Burlington and Quincy section, has the same composition, but the failures are not so numerous. Carbon 58 Phosphorus 10 Manganese 80 to 1.10 Silicon 20 The next most numerous head failures are in the A. S. C. E. 90-pound on tangent, 15J failures per 10,000 tons, and on curve 12J failures per 10,000 tons laid. The P. R. R. 100-pound head failures on curve are 12.8 per 10,000 tons laid, while the head failures on tangent are small, and the head failures of the New York Central 80-pound are about as large, both on tangent and curve, 11.4 per 10,000 tons laid. The A. S. C. E. 80-pound on tangent, the P. R. R. 85-pound on tangent, and the A. S. C. E. 85-pound on tangent and curve have had the same number of head failures as the New York Central 80-pound. The A. S. C. E. 100-pound on tangent and curve comes next, and then 852, 85-pound on curve, while the rest were all less than 5 failures per 10,000 tons laid. The breakages are most numerous in 85 N, 85-pound on tangent, 9.6 per 10,000 tons laid, and next of 852, 85-pound on tangent, with the A. S. C. E. 90- pound on tangent and the Dudley 80-pound on curve, both the same, following closely. Next comes the New York Central 80-pound and 852 85-pound on curve and the Boston and Maine 75-pound on tangent, all the same, and then A. S. C. E. 100 and 85-pound on tangent. The breakages of the others are less than 4 per 10,000 tons laid. It will be observed that the breakages of so-called stiff sections are more numerous than those of the lower sections with the heavier head. The carbon is generally higher in the C. B. & Q. sections than in the A. S. C. E. and P. R. R. sections. The web and base failures are less than 4 per 10,000 tons laid. Plates V and VI present photographs of typical rail failures collected by the committee. Nearly nine million of tons of Bessemer steel rails, from seven different mills and varying in weight from 100 pounds to 75 pounds, were reported in the tracks of the American railroads on October 31, 1910. This corresponded to 21,503,803 rails, and for the twelve-month period from October 31, 1909, * "n. 12 STEEL RAILS to October 31, 1910, there were 30,086 failures or one defective rail for every 714 rails laid in the track. It will be interesting to turn to the conditions of twenty years ago. The following table * shows the rail failures on one of the American railways during the years 1884 to 1888 inclusive. In track, June 1, 1884 121,685 tons In track, January 1, 1889 162,526 tons Removed from track, 1884 to 1888 inclusive, on account of: Broken 1,293| tons Bruised l,435f tons Split l,353f tons Worn out 28| tons No fault 35f tons Total 4,147 tons The record is deceptive in some respects without an explanation. Many of the breaks in the older rails were caused by punching bolt holes. The record of the bruised or battered rails, which constituted the largest item, would have been still greater, except for the fact that long pieces of track laid with soft or so-called " pewter" rails showed up in such bad shape that they were taken up and the rails sent to branches or used in sidings after having been in use only a few months on the main line. The road received the last of these soft rails in 1884, and the record given below of the rails received in the following four years is very good. All of the rails purchased in this period weighed 65 pounds per yard, but after 1888 an 80-pound section was adopted as standard. It will be observed that there were no failures from bruising in the harder rails received after 1884. Year Rolled. 1885 18 86 1887 1888 Total. Total number of rails received during year Rails removed to April 1st, 1889. Account: 23,208 39 13 52 23,156 0.22% 0.06% 21 29,171 5 12 17 29,154 0.06% 0.02% 7 41,678 43 16 2 61 41,617 0.14% 0.07% 24 30,366 4 1 2 30,359 0.02% 0.02% 7 124,423 91 Bruised Split 42 No fault 4 Total 137 Number of rails in the track, April 1st, 1889 Defective rails: 124,286 * Cylindrical Wheels and Flat Topped Rails for Railways, D. J. Whittemore, Trans. Am. Soc. of Civil Engrs., Vol. XXI, 1889, pp. 185, 186. DEVELOPMENT OF THE PRESENT SECTION 13 There appears to have been a critical period occurring about every twenty- years in the history of the rail. When the iron rails replaced the old strap irons and other early forms of track construction, they proved very satisfactory for the light wheel loads of the day. The wheel loads, however, were rapidly increased and soon demanded heavier sections and a metal better able to resist wear at the running surface of the rail. It was claimed that the metal in the larger sections was poorer than that found in the early iron rails. Various ex- periments were tried with rails having steel heads, but it was not until the in- vention of the Bessemer process for making steel, which enabled a stronger and more uniform rail to be made, that the difficulty was successfully met. The use of steel in place of iron for rails commenced about 1865 and enabled heavier wheel loads to be used with safety. The early steel rails were generally made of mild steel which, while suitable for the loads of the early seventies, was found to be too soft for the heavier equipment of the next decade. The situ- ation was unfortunately complicated by the experiments on the Pennsylvania Railroad which showed, or seemed to show, that low carbon steel rails were to be preferred to those made from steel of greater hardness, and for several years following 1881 the rails were made too soft, and, while there was not a return to the serious difficulties of the time of the iron rails, the condition of affairs was far from satisfactory. Relief was found by increasing the hardening constituents in the steel, but with the constant increase in the weight of engines and cars, as well as the greater density of traffic incident upon the growth of the industrial resources of the country, the situation again reached an acute stage about 1905 when the failures of rails became so numerous as to cause the gravest concern on the part of those in charge of the operation of the roads. The failures as before were principally a question of wear rather than of break- age. It appeared that each increase in section produced a rail that wore out more rapidly than the lighter section which preceded it. This condition was further accented by the form of the American Society of Civil Engineers' sections with their thin bases, which turned black in the rolls while the heads were still hot, and the fact that the larger sections took more time to cool and so underwent a partial annealing, making the metal more readily abraded. Three principal reasons were advanced as to the probable cause of the poor service of these latter rails. It was claimed that the wheel loads in use in this country were exceeding the limits of strength of the steel in the rail and, without resorting to extraordinary methods of manufacture and consequently greatly increased cost, the rails could not be made to carry the loads imposed 14 STEEL RAILS upon them with a proper degree of safety. The standard sections then in use were those of the American Society of Civil Engineers and this design of rail, in the heavier sections then demanded, was stated to be an impracticable one to roll. The manufacturers of rails proposed these explanations as the real reason which accounted for the failures of the rails in service. The railways, on 'the other hand, while admitting that the metal of the rails would not stand the heavy wheel loads, claimed that this was due to the fact that the steel was of poorer quality than that obtainable in rails of earlier make, and that sufficient care was not being given to the details of manufacture in the various processes at the mills. The increase in the number of rail failures of the type designated as "crushed heads" and "split heads" the manufacturers claimed was caused by the metal breaking down under the excessive pressure of the heavy wheel loads, and the railways contended that they were due to some defect in the structure of the individual rails. No one at all conversant with the situation will attempt to maintain that the subject is not a pressing one. The making of steel rails for use under high-speed passenger trains is something more than a mere commercial propo- sition. Both the producer and the consumer have great responsibilities in the matter, and neither can lay them aside nor shift them upon the other. 2. Present Sections Realizing the importance of the question, the American Railway Asso- ciation appointed a special committee on Standard Rail and Wheel Sections. This committee, through a subcommittee on which the manufacturers were represented, devoted a large amount of time and attention to the matter of sections and specifications for steel rails and presented a preliminary report to the association, October 1, 1907. While the A. S. C. E. section was apparently well adapted for the light- weight rails of 65 pounds and 75 pounds in use when it was designed, the increase in weight on railway wheels (see Fig. 2) necessitated a heavier rail, and the manufacturers of rails claimed that it was difficult to make such rails of the A. S. C. E. section, due to the thin edge of the base. Accompanying the report of the committee were two series of proposed standard rail sections: Series "A " designed to meet the requirements of those who advocate a rail with thin head and a high moment of inertia, and series "B" to meet the requirements of those who think that there should be a narrow, deep head, with the moment of inertia a secondary matter. These sections are shown in Plates VII and VIII. DEVELOPMENT OF THE PRESENT SECTION 15 The one known as Series "A" is characterized by a shallow head, wide base, thin flanges, and a greater height of section than Series "B." It is appar- ently advocated by those who think that more of the duty of the track should be borne by the rail and less by the other elements. It is obvious that the stronger the rail, as a beam or girder, the more the strains are distributed, and the less need, therefore, for exacting attention to the other features of track maintenance. Its advocates think that the distribution of metal between head, web, and foot, is such that the rolling difficulties, and especially the question of finishing temperatures, can be met with better success. 6aooo •$ "§ 3Q00Q 8 % £2Q000 QOOO Curve Showing Increased "Greatest Load'on each Me. 1 Dates was Fig. 2.- 6QOOO £ 4a0 °° ^ § 3 2Q000 1Q0OO Curve Showing the Increased Average Weight on each Mb . 1 1 >s i9oo im m Dates ms i Axle Loads, 1885 to 1907. (Railway and Engineering Review - It is entirely problematic whether this section will prove the best of the two under consideration, and especially whether the transference of more of the duty to the rail will result in ultimate track economy. Those who oppose this section fear that the shallow head is an element of weakness. According to their view, with such steel as it is at present possible to get in rails, the pounding of the heavy traffic will lead to such crushing and splitting of the heads, owing to internal physical defects in the metal, that the section will prove a failure, especially on roads with heavy wheel loads and dense traffic. Series "B" is modified to meet this latter view. The distribution of metal is believed, as in the "A" section, successfully to meet the manufacturers' criti- cism, the head and foot in the 100-pound rail having slightly over forty per cent each of the metal, and the web the balance. This section is weaker as a girder than the "A" section, and it would appear that for lighter rails the 16 STEEL RAILS section "A" should preferably be used to obtain the greatest stiffness. Where the wheel loads are sufficiently large to require the heavy head of the "B" section, the design of the rail should, however, approach more nearly the latter section, even at the expense of lack of stiffness which may be compensated for by strengthening the track structure or increasing the weight of rail used. There is no good reason why the same characteristics of design should be carried out for an entire series. With the excessive loads borne by the heavier rails more attention must undoubtedly be given to the effect of the concen- trated pressure at the point of contact of the wheel and the distribution of this force to the base of the rail. The bending stress while of equal impor- tance can be reduced by strengthening the track structure as a whole. Hence under the most severe conditions a section should be used in which ample provision has been made for the former stresses and the question of the bend- ing stress, while not lost sight of, becomes of secondary importance. As the section decreases in weight the importance of the stiffness of the rail increases, until in the lighter sections, supporting small wheel loads, a very much higher relative moment of inertia is to be desired than in the heavier rails of the same series. The sections "A" and "B" have been proposed as "recommended prac- tice" by the American Railway Association, and have been referred to the American Railway Engineering Association to study and accumulate data and make a report after the sections have been sufficiently tried in service to enable an opinion to be formed as to their respective merits. The American Railway Association Committee, in its report of October 1, 1907, submitted a statement of cardinal principles which should govern the design of a series of rail sections, as follows: (a) There should be such a distribution of metal between the head and the base as to insure the best control of temperature in the manufacture of the rail. (b) The percentage of metal in the base of the rail should preferably be equal to or slightly greater than that in the head, and the extremities of the flanges should be sufficiently thick to permit the entire section to be rolled at low temperatures. The internal stresses and the extent of cold straightening will be reduced by this means to a minimum, and at the same time the texture of the section will be made approximately homogeneous. (c) The sections should be so proportioned as to possess as great an amount of stiffness and strength as may be consistent with securing the best conditions of manufacture and the best service. DEVELOPMENT OF THE PRESENT SECTION 17 (d) The following limitations as to dimension details of the sections are considered advisable for the various weights per yard: I. The width of base to be \ inch less than the height. II. The fishing angles to be not less than 13 degrees and not greater than 15 degrees. III. The thickness of the base to be greater than in the existing sections of corresponding weight. IV. The thickness of the web to be no less than in the existing A. S. C. E. sections of corresponding weight. V. A fixed percentage of distribution of metal in head, web, and base for the entire series of sections need not be adhered to, but each section in a series can be considered by itself. VI. The radii of the under corner of head and top and bottom corners of base to be as small as practicable with the colder conditions of rolling. VII. The radii of the fillets connecting the web with head and base to be as great as possible, for reinforcing purposes, consistent with securing the necessary area for bearing surface under the head for the top of the splice bar. VIII. The sides of the head should be vertical, or nearly so. IX. The radii of the top corners of the head should not be less than | inch so long as the wheels continue under the present standard of the Master Car Builders' Association. The principles (a), (&), and (c), above enumerated, appear to cover the proper design of T-rail sections. The (d) limitations as to dimension details should be approached tentatively rather than regarded as a cardinal principle. Since October, 1907, a large tonnage has been rolled of rails substantially in accordance with the new sections, both series "A" and "B." It has been dem- onstrated that these sections can be finished in the mill at a lower temperature than the A. S. C. E. sections,* and therefore a finer grained and better wearing rail should be secured with the new section. However, great care must be ex- ercised at the mills to see that rails are actually rolled at lower temperatures. The 90-pound series " A " is now used on a majority of the Western prairie roads, and the " B " section is used on the group of coal roads in Maryland and Virginia. On account of the heavier head found in the " B " section, it seems to be preferred by the crooked roads of the East, especially those in the * This refers to the temperature of the head; no part of the new sections is finished as cold as the thin bases of the A. S. C. E. rails. 18 STEEL RAILS mountains of Pennsylvania, Virginia and Maryland ; while on the prairie roads, where little curvature is found, the series " A " rail with the lighter head finds more general use. On June 5, 1907, a joint committee of the Pennsylvania Railroad system — Mechanical and Civil Engineers east and west of Pittsburg — was appointed to study the rail question, and on September 20, 1907, their labors resulted in the designs for 85-pound and 100-pound rail sections shown in Plate IX. It will be noted that the sides of the head are vertical in the 85-pound section and sloping in the 100-pound section. This difference is not intentional, but arises from the method of constructing the sections. The bearing surface underneath the head for supporting the shoulder of the splice bar was con- sidered of great importance, and the committee was not warranted, in the light of past experience, in reducing this surface. This was therefore fixed at not less than the existing bearing surface. As the same equipment is run over the 85-pound and 100-pound sections, there was no good reason why the width of the head on top should not be the same in each case, and, after studying the contour of the wheel tread, this width was fixed at 2| inches. The result was sloping sides in one case and vertical sides in the other. This section, known as the "P. S." section, is a step farther away from the "A" section. It has a still heavier head, a narrower base, and thicker flanges than the "B" section. The radius of the web is smaller, thus producing more of a buttress where the head and web join. The experience of the Pennsylvania system seems to be that with their heavy wheel loads and dense traffic, and with the grade of steel that it is now possible to get in rails, more rails fail from crushing and disintegration of the head, apparently due to the pounding of the traffic, than from any other one cause, and accordingly in this section the maximum effort has been made to strengthen the rail in its weakest point. The distribution of the metal is satisfactory, and the strength of the rail as a girder or beam is practically the same as the "B" section. In Europe a T-rail section is used. The Vignole rail used extensively abroad was invented in England in 1836 by Mr. Charles Vignoles. Plate X shows the type of Vignole rail used on the French Eastern Railway. It is their intention eventually to modify the section by decreasing the height of the head a little and increasing its width. The weight of the section is 45 kilos per meter or about 91 pounds per yard. The maximum axle load is about 40,000 pounds. DEVELOPMENT OF THE PRESENT SECTION 19 Plate X shows the rail used on the Paris, Lyon and Mediterranean, weigh- ing 48 kilos per meter, or 96.7 pounds per yard. The maximum axle load on this road is, for passenger service, 38,000 pounds, and, for freight service, 35,000 pounds. Plate XI illustrates types of German rails. The figures show that the corner radius of the head in all the rails is y-g- inch, as prescribed by the " Tech- nical Conventions of the Union," which also recommends a width of head of at least 2\ inches with a minimum radius of the top of the head of 7f inches. On the majority of the German rails the latter radius is from 7| to 8| inches. An inclination of io is given to the rails, which is obtained by the use of wedge tie plates. Plate X shows the Vignole rail recently used on the Egyptian State Rail- ways, of 46 kilos, or 92.7 pounds.* In England the idea seems to prevail that a T-rail track is undesirable, and a double-headed, or bull-headed, rail is generally used on the English rail- ways. Plate XII shows the construction of the permanent way of the Midland Railway of England, and Plate XIII the permanent way of the London and North Western Railway of England. On the latter road the British standard bull-headed rail is used, as shown on Plate XIV. Plate XV shows the British Standard flat bottom rail. For street railway work either a T-rail or grooved-rail section is employed, as illustrated on Plates XVI and XVII, which show the sections recommended by the American Electric Railway Engineering Association. This association has only taken up the study of girder and high T-rail sections, and the sections of tram rails given on Plate XVI, while representative of good practice, are not the standard sections of the association. Plate XVIII shows the British Standard tramway rails. While the T-rail is generally recognized in this country as having superior merits for street railway purposes, it is necessary, however, on heavily traveled streets to use the grooved rail. The use of a number of different rail sections in street railway work is open to the same objections as are found in steam railway practice, and the tendency is toward the adoption of standard sections. In determining the proper form for a rail, the subject should be considered from two points: First, and most important, the duty required. Second, and about equally important, the influence of detail of manufacture upon the char- acter of the finished product. It is perfectly proper that all the stresses to * This rail has been replaced by another weighing 95 lbs. per yard, according to British Standard sections, which was laid from the year 1911. 20 STEEL RAILS which it will be subject should be considered and calculated, but its ability to resist them will depend quite as much upon the character of the metal as upon the form of section. In considering the duty, we have first to examine the external forces acting upon the rail, which consist of the pressure exerted by the wheel on the rail and the supporting forces represented by the ties. When these are known, the stress induced in the rail can be calculated for different sections. CHAPTER II pressure of the wheel on the rail 3. Speeds of Modern Locomotives The eight-wheel or American engine was formerly the favorite type for fast passenger service. The arrangement of this engine provides a four-wheel leading truck and four-coupled driving wheels and afforded ample starting capacity for the trains of moderate weight used at that time. The Atlantic type is the result of the demand for large heating surface and grate area in combination with large driving wheels in an effort to meet condi- tions which could not be met successfully by the preceding American-type engine. The Atlantic-type engine combines a four-wheel leading truck and four-coupled driving wheels with trailing wheels. The increase in the weight of the train due to heavier equipment and longer trains has resulted in the use of the Pacific locomotive with six-coupled wheels in place of the Atlantic type with four-coupled wheels. The latter engine is better suited to high-speed service than the former, but it cannot accelerate heavy trains to running speed nor maintain speed on grades as well as the Pacific. The internal friction of the Pacific engine is much greater than that of the Atlantic and it reaches its speed limit sooner, and in fact these powerful engines have not been able to show any material increase in the speed of our fast trains. A train * was recently made up for test purposes which was intended to represent modern express equipment which could be hauled at high speed on level track. The six cars weighed 350 tons, and the Pacific locomotive 194 tons, total 544 tons. The Pacific locomotive, which was selected for its good record on that line, was not able to accelerate the train to more than a fraction above 60 miles per hour on a straight level track where atmospheric conditions were normal. On several railways in the West it was for a time thought that it would be necessary to electrify the mountain divisions in order to attain speeds which would carry the large volume of traffic over the grades and avoid congestion and blockade. The Mallet locomotives have overcome this difficulty, and their * Railway Age Gazette, January 28, 1910. 22 STEEL RAILS remarkable performance has for the time rendered the electric locomotive on mountain lines, where there are no long tunnels, unnecessary. On account of the good results obtained by the use of the Mallet compound locomotives it will prove interesting to consider the question of adopting these machines for fast service. The principal advantage to be derived from the use of the Mallet type appears to lie in its ability to develop enormous force at the draw-bar, but it will be observed that these forces are only possible at compar- atively low speeds. At speed,* whatever the type may be, it is the boiler and not the adhesion that limits the output of power. The moment the speed is increased by any considerable amount, high draw-bar forces become impossible and the wheel arrangement peculiar to the Mallet type unnecessary. The assumption even of a moderate speed will permit wheel arrangements, now common, to absorb the full power of the largest boilers now considered practicable. For example, assume that a locomotive is used which is to have sufficient boiler capacity to permit 2000 h.p. to be developed in compound cylinders at all practicable speeds. Such a locomotive would require a boiler having in the neighborhood of 5000 feet of heating surface which, if fired with coal, would need to be supplied with 6000 or 7000 pounds per hour. The draw-bar force equivalent to 2000 h.p. for several different speeds is as follows: At 1 mile an hour, the tractive force will be 750,000 lbs. 5 miles : 7* 10 20 30 50 150,000 100,000 " 75,000 " 37,500 " 25,000 " 15,000 " Assuming the driving axle of the proposed locomotive to carry a load of 50,000 pounds, and assuming the adhesion to be 25 per cent, each driving axle will serve to develop 12,500 pounds tractive force. A Mallet compound having eight axles would be capable of developing a maximum tractive force of 100,000 pounds, which force is equivalent to the development of 2000 h.p. in the cylinder at a speed of 1\ miles per hour. At speeds lower than this the adhesion derived from eight axles will not permit the cylinders to develop this rated power, and for speeds higher than this the full adhesion of eight axles will not be necessary to the development of 2000 h.p. * Railway Age Gazette, April 22, 1910. PRESSURE OF THE WHEEL ON THE RAIL 23 Table I shows fast and unusual runs in the last three decades.* The foregoing table is severely condensed. f The time in every case is from the beginning to the end of the run, including stops. In speeds alone, for moderate distances, there has been little change since 1895. For example, the engines of the Atlantic City Railway make substantially the same time as was made over the same line ten years ago; but with the larger boilers and fireboxes now used, heavier trains are hauled without loss of speed. The Empire State Express of the New York Central, which for years was limited to four cars, now usually has five cars, and still makes its trip of 440 miles at the scheduled speed of * Locomotive Dictionary, 1909 Edition, Chicago. f March 1, 1901. — The record of 107.9 miles an hour is given by an officer of the road. The grade was descending, mostly at 30 feet per mile. March 24, 1902. — This run was made on a descending grade, which for some of the way was as much as 32 feet per mile. June 21, 1902. — This run is notable by reason of the rising grade. Altoona is 861 § feet higher than Harrisburg. June 19, 1903. — This run was made without a stop, but there were two engines. The weight of the train was 1,008,000 pounds. There are a number of long ascending grades in the line. August 8, 1903. — On this and the later run between the same places there were, of course, many changes of engines. The record gives no data concerning the sizes of the engines, but most or all of them were of the most powerful types made in the United States at that time. June 9, 1904. — On this run engines were changed at Bristol. The dimensions given are those of the engine used on the second stage of the journey. A car was left at Bristol and the weight given is the average weight for the whole journey. The first engine had drivers 6 feet 8 inches in diameter, four-coupled; cylinders, 18 X 26 inches. The train making this run was the regular mail train scheduled to run regularly, without a stop, from Plymouth to London in 4 hours 25 minutes. July 20, 1904. — This is the best record which has been made over this line. The run of June 19, 1906, was made with one more car. 1905. — Eighteen hours between New York and Chicago is the regular schedule time of one daily train each way over the New York Central lines, and one over the Pennsylvania, the latter being about 60 miles shorter. There is no published record of less time through, though on many occasions the trains of both roads have made up much lost time. The run of November 3, 1905, is an example of what has been done in such cases. In this run the number of cars was three, except over portions of the road where a dining car was added, making four. October 23, 1905. — This run and that of May 5, 1906, were not undertaken with a view of making the highest possible speed, and each of the divisions over which these trains traveled has been traversed no doubt in shorter time; but these transcontinental records are notable for the long distances covered, even though the time be not the very highest of which the engines are capable. Both of these runs were made by special trains throughout, except that in the run of May, 1906, the run east of Buffalo was that of the regular Empire State Express. June 19, 1906. — On this run a distance of 12 miles was traversed in 8 minutes (90 m.p.h.). STEEL RAILS rocpocp ■ -cp 6 S S oo s ogg gogg gggo oooo oggo o ooos S g£ go O J 8§g,M Ph s g'-S g8\£» ^odm gzom 1 - 1? * 7 i * Pj :=8P- .jd* OS d ddd^^g. - |>^=3 ^H^l>< « oi^^-g 4^ >^ I »d, : J £| ^ll ^^5 '-"loGc "111 ^™ tf-s-sll**) «sd£l*,8JJ I ooSh izzjj o;ss5; III 111 ^ IH&ii ll'il 1JM Hi PhOoS OSmW PhHSH 3o2s 6W N^ \ ■FlB.o/V 9Q !80_ /" \ M.D. / B.D. \ , /^' ^> ***4= =^r \ \ A \ / \ \ J \ /M ^■"^ \ \> ^J \ \ J \ \ \ \J ALL DRIVERS OQOOO Fig. 7. — Rail Pressures. Ten-wheel Engines (Light Weights). (Am. Ry. M. M. Assn.) data obtained from eight- and ten-wheel engines on the C. M. & St. P. Ry. The following are the principal dimensions and weights of each * * Report of Committee on the Wear of Driving-Wheel Tires, Proceedings Am. Ry. M. Mech. Assn., 1895. PRESSURE OF THE WHEEL ON THE RAIL 37 Eight-wheel Engine. Ten-wheel Engine. 16 by 24 inches 160 pounds 56 inches 8 feet, 6 inches 7 feet, 2\ inches 2i inches 480 pounds 54,000 pounds 19 by 26 inches 10 feet 3J inches The piston, piston rod, crosshead, and front end of the main rod are taken as reciprocating parts, the back end of main rod as a revolving weight, in all calculations which follow. The weights of the ends of the rods were found by supporting each end at the center of the box or bearing, and resting them alternately on scales. The eight-wheel engines had the entire weight of the reciprocating parts balanced, by adding one-half this weight in each driving wheel to the weight necessary to balance the revolving parts' when weighed at the crank pin. The ten-wheel engines were not counterbalanced alike, but all agreed in having the forward and back wheels overbalanced; that is, with a heavier counter- balance than that required to balance the revolving parts only; while the main wheels of thirty-five of the fifty-three engines from which measurements were taken were underbalanced for the revolving parts alone, and all of them under- balanced according to the rule of adding to the weight necessary to balance the revolving parts two-thirds of the weight of the reciprocating parts, divided equally between the driving wheels. The counterbalance in the wheels of each of these engines was carefully weighed by resting the journals of each pair of drivers on level straight edges, placing the crank horizontally, and hanging on the crank pin a sufficient weight to just balance the counterbalance opposite. From this weight the weight of the revolving parts attached to that pin was subtracted, the remainder being the amount of overbalance weighed at the crank pin. If the weight of the revolving parts exceeded the weight so found, of course the wheel was under- balanced by the amount of such excess. The actual average condition of the counterbalance in the wheels of the fifty-three ten-wheelers was as follows: Average overbalance weighed at the crank pin above that required to balance revolving parts only: Front wheel 271 pounds overbalance Main wheel 80 pounds underbalance Back wheel 237 pounds overbalance. 38 STEEL RAILS These weights* are used in the calculations for the ten-wheel engines plotted on Fig. 7. The following formulae have been used in calculating the forces in action: NOTATION P = Pressure of one driving wheel on rail. W = Weight of each wheel on rail, engine at rest. C = Centrifugal force of the excess weight in the counterbalance over that required to balance the revolving parts. A = Horizontal accelerating (or when negative retarding) force of the recip- rocating parts. Pi = Pressure against crosshead pin from steam in cylinder. a = Angle of the crank with the horizontal. N = Ratio of length of main rod to length of crank. Hence, P = W - C sin a + ( Pl ~ A) • (1) 'A/2 Vsi snra But, w = Weight of the excess in the counterbalance over that required to balance the revolving parts. v = Velocity of the center of gravity of the overbalance. r = Radius of the center of gravity of the overbalance. w' = Weight of the reciprocating parts. v' = Velocity of the crank pin. I = Length of the crank. g = The acceleration of gravity, 32.16. Hence, C =—, (2) gr A W ' V ' 2 /n\ A = — =- cos a. (3) gi Or, by substituting in (1) the values of C and A given in (2) and (3), Pi T~ cos a wv 2 , V gl / /,x P = W sin cH y (4) gr ijp_ _ 1 V sin 2 a The above formulae include the centrifugal force of the overbalance in the drivers, the effect of the acceleration and retardation of the reciprocating parts, and the angularity of the main rod. Formula (3), for the acceleration of the reciprocating parts, assumes that they move as they would were the main rod * These weights are the equivalent weights at a distance from the center equal to the crank length, and not the actual counterbalance weights used. PRESSURE OF THE WHEEL ON THE RAIL 39 infinitely long, but the error this produces is too small to affect the accuracy of the results, while the formulae are much simplified. The left-hand ends of the diagrams correspond to the position of the engine when the right crank is on the forward center, positive rotation being that produced by running the engine forward. The pressures upon the piston used in the calculation for Figs. 6 and 7 were obtained from actual indicator cards taken at these speeds, and with a point of cut-off found by the examination of a large number of cards to be the usual point at which an engine is worked at the speed taken. The points of cut-off used are: Eight-wheel engine, just starting, 22 inches; 40 miles per hour, 6 inches; 60 miles per hour, 6 inches. Ten-wheel engine, just starting, 22 inches; 10 miles per hour, 13 inches; 20 miles per hour, 11 inches; 30 miles per hour, 8 inches; 40 miles per hour, 6 inches; 60 miles per hour, 5f inches. Curves for just starting, ten and twenty miles per hour, show that the total pressure of the main driver on the rail is always greater at these speeds and cut-offs than the actual weight of driver on the rail when the engine is at rest. Fig. 13. — -Damaging Effect of Badly Balanced Locomotive. This is due to the angularity of the main rod always causing an increase of pressure on the main wheel. There is, of course, a corresponding upward pressure on the guide, reducing the weight on the truck. Figs. 8 to 12 are for heavier engines and are calculated from some of the largest engines that have been built of each type. Fig. 13 shows, the damaging effect upon the track of a badly balanced locomotive. 40 STEEL RAILS A / \ -=-- *r=r=: =.*&- /~ s ~^ v ----- ^--m :=. F ^, 7000O 600OO / „\ 5OO0O "^-Cr" -.--J — i-^ 70000 MD f _ 50O0O v --» ~v^ ^L _^>* A I4O0OO W 120000 rev ftso»* r ^ J h \_y aoooo 70000 80 Ml PER MR. Vd. //"" N\ ^ — =^Z / x p.bT\ I6§Q0 ©GO©© Fig. 8. — Rail Pressures. 442 (Atlantic) Type Engines: Cylinders 21|" X 26", Wheels 79", Workin Pressure 180 lbs. (Am. Locomotive Co.) PRESSURE OF THE WHEEL ON THE RAIL \M.D, r.&B.Df 9Q I8Q 27Q 36Q V^ M.D. 60O0O -~ « .^.-^ _= = - E8B.D 50000 IO Ml. =ER HR. ' / -^M.D. ""----___ ■ >/ X \ / / / >v M.D. -==.-=.-= .==^- ^"= — f^rdV-' 20 Ml. PER HR. M.D. *=■- — ^" ----- — -- •vM.D. f.sb.d\ ^.-~ — ^>- ■*= r - £^~ 40 Ml. PER HR A H IOM.P.H STARTING 20M.RH. 30M.PH. m 40M.PH. ^/ /50MPH VA- 60M.RH. ALL DRIVERS 3HT DRIVERS^ £ LEFT DRIVERS Fig. 9. — Rail Pressures. 462 (Pacific) Type Engines: Cylinders 22" X 28", Wheels 79", Working Pressure 200 lbs. (Am. Locomotive Co.) 42 STEEL RAILS RIGHT SIDE 9Q iao 27o 3e o /- -V- / / \ ER HOUR S 1 2 ?0 3 50 oooo \» / / VT B *^\ ^c- — \ SOOOO \ \ \ / / \ / \ 50000 K-" ^i 4 !^ ^ //<:: ^v 50000 v / \ A v\ sjsr« a ^■^ K \ y 3 ° MPM ISOOOO 140000 I3QOOO \y ALL DRIVERS ~N"> / / ^T / N^ Fig. 10. — Rail Pressures. 460 (Ten-wheel) Type Engines (Heavy Weights) : Cylinders 22" X 26" Wheels 69", Working Pressure 200 lbs. (Am. Locomotive Co.) PRESSURE OF THE WHEEL ON THE RAIL RIGHT SIDE 60000 70000 60000 -=-— — "-jizj^ f^ ^=- 30MI. RIGHT SIDE O 56 y \\ / X / f - "N \ // 1/ \\ \JV ^ ', 3 \ / / RIGHT DRIVERS. Fig. 11. — Rail Pressures. 260 (Mogul) Type Engines: Cylinders 21" X 28", Wheels 63", Working Pressure 200 lbs. (Am. Locomotive Co.) STEEL RAILS "^ b;d.> 700O0 eoooo ^ i- l i20v. soooo /~ V M.D. M ^ *"' y^7J"~^v ~N_ y^ ~-<\ ^v ^/J ^Cpd \ -v "\\ \ ^ A A ' \ """""n A J) ^N ^-fr— 20M.P.H. i 30MRM. /UoMPH /sOM.P.M. \\ u RIGHT DRIVERS — eoooo oooo© Fig. 12. — Rail Pressures. 280 (Consolidation) Type Engines: Cylinders 23" X 32", Wheels 63", Working Pressure 200 lbs. (Am. Locomotive Co.) pressure of the wheel on the rail 45 6. Effect of Irregularities in the Track Fig. 14 shows the exaggerated profile of the rail observed by M. Cuenot in his track experiments. Figs. 15 and 16 show the rail profile taken with a Railroad Automatic Track Inspector machine. These diagrams show the unloaded profile of the rail, or the permanent set left in it by the passage of the trains. Evidently the loaded profile will be below the unloaded line, and both profiles will probably show the same general features, as indicated by the approximate loaded position of the rail shown by the dotted line in Fig. 16. The wheel as it passes over the curved surface of the rail shown in the figure is constrained to move in a curved path whose radius is about 5000 feet, Mv 2 and the pressure of the wheel on the rail is the centrifugal force, C = -5-' directed away from the center of curvature. For 30,000-pound wheel loads, M = — = ' 1fi , where the units are in pounds and feet. For 60 miles per hour, _ 5280 X 60 V 60 x 60 and R = 5000. mi. e n Mv 2 30,000 x 88 x 88 1 , , c , Therefore C - -^ = ^ x mQ - 1445 pounds, which is the excess wheel pressure caused by the irregularity in the track shown by the figure. To be on the safe side, it would seem desirable to increase this amount. If, however, 4000 pounds be taken to represent the excess wheel pressure, due to this cause, an ample factor of safety will apparently have been provided. It will be seen from the above that the increase of wheel pressure, due to any change in the grade line, will be so small as to be negligible. It is good practice to change from one rate of grade to another with a vertical curve, changing the grade at each 100-foot station by 0.1 feet; this would give a radius for the vertical curve of 50,000 feet, and a corresponding value for C of about 150 pounds. Let us now consider the path of the wheel when passing over the summit between two of the depressions shown in the track profile, Fig. 15. When the wheel is in the act of leaving the valley, or depression, its path lies in a direction away from the surface of the rail before it. It is, however, under the influence of two forces, — neglecting for the moment the action of the springs. First, its 88 feet per second, STEEL RAILS i+V. y ire?-l\M PRESSURE OF THE WHEEL ON THE RAIL 47 momentum, acting along a line of direction tangent to the vertical curve of the rail; and, second, the force of gravity. The trajectory of the wheel acting under - Rail Profile taken with a Railroad Automatic Track Inspector Machine. •"\ \ SURFACE O F TRACK^ J --^ ^-^^ -~^ ,*.-- ' ~~- ~~_r" •^O^so- - '"PATH O F WHEEL Fig. 16. — • " Valley " or Local Depression in Track Profile. these forces will be a parabola with its axis vertical. The greatest height of ascent, y, and the horizontal range, x, are given by the following equations: y = h sin 2 a, x = 2 h sin 2 a. h being the ideal height due to the velocity, we therefore have for a speed of 60 miles per hour, v 2 = 2 gh, ~2g , = 121 feet. 2 x 32.16 " Fig. 17 is derived from the same record as that from which the diagram of Fig. 15 has been taken and shows a summit be- tween two depressions in the profile of the track. We see from the figure that the value of a is ' 0° 14' . Substituting these Values Fig. 17. — Summit between Two Depressions of Track Profile. in the expressions for x and y, there results for the greatest height of ascent 0.002 feet, or 0.024 inches, and for the horizontal range, 1.97 feet. 48 STEEL RAILS SET LOAD iW FREE 1 V4" 21870 5/8" 27300 SET LOAD 4V FREE 2" 20650 1*6" 25812 Fig. 18. — Locomotive Driving Wheel Springs. PRESSURE OF THE WHEEL ON THE RAIL 49 Fig. 17 shows that this curve practically coincides with the profile of the rail. It is hardly conceivable, therefore, that the wheel can leave the rail when passing from one depression to another, as the action of the springs, as well as the resilience of the rail, which would tend to prevent this, are neglected in the preceding discussion. 7. Effect of Rocking of the Engine The pressure caused by the rocking of the engine on its springs can best be determined by observing the amount the springs deflect under their load. By referring to Plates XX and XXI, it will be seen that the wear of the guides of the driving boxes will give a means of telling how much the springs deflect. The maximum amount of wear is probably about one inch. Turning to Figs. 18 and 19, which show the springs used for the locomotive drivers, we see that the depression of the spring one inch corresponds to a range of pressure of about 8000 pounds. However, as the rocking of the engine causes at times a less pressure as well as a greater on the springs, one-half of this amount, or 4000 pounds, should be taken as the pressure which will cause the spring to deflect an amount equal to that obtained under service conditions. A careful series of experiments have been made by Messrs. Coes and Howard * to determine the live load on locomotive driving springs under actual running conditions. The apparatus consists of three distinct parts: (1) a recording device, which fits on the spring band or saddle; (2) a spanner bar or beam, which is fastened to each end of the spring link hangers and is connected to the record- ing apparatus; (3) a battery box, which is in the cab with rheostat, switches, keys, clock, and all the necessary controlling mechanism. See Figs. 20, 21, and 22. The recording apparatus (Fig. 20) is in a box, which is bolted to a steel plate (1) by four bolts; this plate in turn is bolted to a U-shaped band (2) which is fastened to the spring band by four hardened steel set-screws. The record is made on metallic-faced paper, 4 inches wide and about 750 feet long. This paper is wound up upon a detachable drum (3) and travels across a curved brass guide plate (4) under two guide rolls (5) on to the main drum (6). * Thesis 1906 at the Massachusetts Institute of Technology, under the supervision of Prof. Lanza. / / f Jr s o i a. DEFLECTION INCHES - Deflection of Locomotive Springs. 50 STEEL RAILS Bm -QBpW dp i ^^§Slrr I jb S^ heostat t&- ^Br __3 DRY BATTERIES Fig. 20. — Recording Device and Cab Controlling Mechanism for Testing Driving Wheel Springs. (Coes and Howard.) £JP " ^BP* ■ // » 2. ik^Ka -J&b^jM * ^■P^* s Mgg P^ ^ Bp^ •'v — Fig. 21. — Recording Device in Place on Driving Wheel Spring. (Coes and Howard.) PRESSURE OF THE WHEEL ON THE RAIL 51 The main drum is driven by a motor (m) behind the curved plate, through a worm and wheel drive (w). The main stylus is on a steel bar (6) machined to fit two steel boxes (7) and is free to slide up and down. Considerable trouble PI zzr f f^J5 - General Arrangement of Apparatus for Testing Driving Wheel Springs. (Coes and Howard.) was encountered with the stylus on account of the excessive vibration and jarring, and finally the type shown in Fig. 23 was designed, which gave entire satisfaction, and with which the whole apparatus was equipped. This is so constructed as to make the stylus spring always work in tension, which is better than using the spring in compression. The spring is suffi- ciently long to be sensitive and still not be thrown from the plate when the engine strikes a curve, a trouble characteristic of all former instruments. Be- sides the main stylus there are three others of identical construction. First, the zero stylus (8), which draws a straight line across the roll and to which all deflections are referred; second a stylus (9) which is on a magnet that is operated by a Morse key in f'ig.23.— Main styiusused in Driving wheel .a. u it.- j i. 1 /im -u- t. • Spring Tests. (Coes and Howard.) the cab; third, a stylus (10) which is on a magnet and is operated automatically by a clock in the cab. The spanner bar (11) is shown in Fig. 21 and needs no description except its method of fastening to the spring link hangers and its mode of operation. It is fastened to the hangers by means of two blocks, which are slotted and fit over the ends of the hangers, these blocks being held on to the hangers by four ~*TO» 52 STEEL RAILS hardened steel set-screws. The spanner bar (11) is connected to the stylus bar (6) by means of a short link (Z). Thus, whatever relative movement is given the recording apparatus by the spring is transmitted as a vertical line on the paper by means of the stylus bar (6) and the spanner bar (11). Hence, since the paper is being driven horizontally by the motor we have a wavy line giving a complete record of every movement made by the spring, and by means of the records made by the key and the times recorded by the clock we can account for most of the deflections due to frogs, switches, curves, crossings, brake applications, and bridges. The cab apparatus (Fig. 20) consists of a suitable box containing a portable storage battery and six dry batteries. The storage battery gives 5 amperes for 8 hours at a pressure of 6.6 bolts. This runs the motor. The six dry batteries operate the clock and the key. On top of the box is a key (K), which is connected by means of flexible lamp cord, fastened to the running board, to the magnetic stylus (9). By means of the key the operator can record by code any observation that may be necessary in working up the records. On the side of the box is fastened a clock, which automatically records 15-second intervals on the paper by a magnetic stylus (10). The motor is kept at the proper speed by a rheostat fastened to the top of the box. The first successful run was made on engine 1064, consolidated type 2-8-0, with 36-inch springs, 17 leaves, 4 full-length leaves 4 inches by f inch. This run was made on the Fitchburg Division of the Boston and Maine Railroad from Boston to Ayer Junction on February 17, 1906. The spring tested was the second (counting from the cylinder) on the left side. From this run was obtained a maximum deflection of 0.34 inch. (See Plate XIX.) A second run was made March 3, 1906, over the same route and on the same engine to see if the same deflections were obtained. The curves obtained by this latter run were practically identical with the test of February 17, 1906. (See Figs. A and B, Plate XIX.) Figs. C D, E, and F present curves taken at other points of the track. The spring from engine 1064 was taken out and sent to the Engineering Laboratory of the Institute ancl tested on the 100,000-pound Olsen Machine. The results of this test are plotted and shown on Fig. 24. Two tests were made, one with rollers under the knife-edges and one without. The set had been measured on the engine and the ends of the leaves had also been marked. The spring was then placed in the testing machine and the loads applied, corresponding micrometer readings of the deflections being taken until the spring had been loaded down to the set as measured on the engine. PRESSURE OF THE WHEEL ON THE RAIL 53 DEFLECTION AS OBTAINED FROM RECORDING MACHINE MINIMUM MAXIMUM \+ _ Q.48^ Q.34" ^,1 O DEFLECTION IN INCHES Fig. 24. — Stress-strain Diagram-Locomotive Driving Wheel Springs. (Coes and Howard.) 54 STEEL RAILS This load was 14,200 pounds, or the static load on the engine, the dead load for which the spring was designed being 14,144 pounds. Next the maxi- mum deflection, as recorded by the spring apparatus, which was 0.34 inch, was put in the spring, the load corresponding being 3500 pounds gradually applied, making a total load on the spring of 17,700 pounds. The excess load applied to the engine when running should be classed as a suddenly applied load. If we consider the relation between the load slowly applied to the spring in the testing machine and that suddenly applied when the engine is in service, we see that in the first case the load gradually increases from 14,200 pounds up to 17,700. The average load acting through 0.34 inch is only 15,950 pounds and the total work done on the spring amounts to: 15,950 x 0.34 = 5423 inch-pounds. In the case of the suddenly applied load under service conditions it will be observed that owing to the load reaching nearly its full intensity before the spring deflects, the load producing the deflection in this case would be obtained by dividing 5423 inch-pounds by the deflection,* or y-^-7 = 15,950 pounds. This amounts to 12.3 per cent more than the static load of the engine on the spring (14,200 pounds) and represents the dynamic augment of the spring-borne weight of the locomotive. It will be noticed that the dynamic augment as determined by these experi- ments is considerable in excess of the figure arrived at by observing the wear of the guides of the driving boxes. In the latter case the average deflection corre- sponded to a load in the testing machine of 4000 pounds. Taking half of this or 2000 pounds as the dynamic load producing the same deflection of the spring, we find a dynamic augment to the 25,000-pound static wheel load used of 08 per cent. This may very probably be accounted for by the fact that the maximum deflection obtained is so infrequent as to cause no perceptible wear. 8. Effect of Flat Spots in the Wheels We have now taken account of all the forces exerted by the wheel on the rail except the impact caused by the existence of flat spots in the tread of the wheel. The violence of the blow upon the track, delivered at every rotation of the flat wheel, is a matter of common observation; but the amount of its force and the damage done thereby are very hard to determine. * See Applied Mechanics, Gaetano Lanza, 1895, page 246. PRESSURE OF THE WHEEL ON THE RAIL 55 A theoretical discussion of the force of the impact is not likely to lead to any practical results because of the indefiniteness of the shape of the spot, due to the rounding of the corners by wear, also to the lack of knowledge of the effect of the springs and the resilience of the track. The kinetic energy of the impact is represented by the expression \ Mv 2 , where M represents the mass and v the velocity. In order to show a loss of energy there must be a change of velocity, but any perceptible change in the horizontal velocity of a moving car, due to the impact of the flat spot, is quite inconceivable. There may, however, be a change in the vertical velocity of the load as the flat spot comes over the rail. Professor Hancock, of Purdue University, has made a very careful study of the mathematical relations existing between the speed, impact, and length of spot.* Following Professor Hancock's analysis, let A, in Fig. 25, be the center of a car wheel D inches in diameter, revolving as shown by the arrow, and CP be a flat spot L inches long just beginning its contact with the rail. The whole i wheel is turning about the point C, and will so turn until P reaches R and the blow is struck on the rail. At this latter instant A will have reached A' and will be moving downward with a velocity represented by the line be. If the velocity of A', which is practically the same as that of the train, is assumed as v feet per second, then -Flat Spot in Wheel. (Hancock.) be = CP V CB = If we regard the mass of the wheel and its load as concentrated at A and call the total weight W pounds, the kinetic energy of the mass just before the rail is struck will be: This formula will give for the energy of impact of a flat spot 2.5 inches long in a wheel 33 inches in diameter, carrying a load of 20,000 pounds when the * Paper read before the Indiana Engineering Society, January, 1908. See also discussion by L. S. Spilsbury, presented by H. H. Vaughan in the American Engineer and Railroad Journal, December, 1908. 56 STEEL RAILS train is traveling 60 miles per hour, 13,800 foot-pounds. At this speed it would seem, however, that the results obtained by the formula would be open to question. In the derivation of the formula it is assumed that the wheel turns about C until P reaches R. This assumption only holds true for speeds from zero up to about five miles per hour; * at speeds greater than five miles per hour the point C will tend to leave the rail, and the whole wheel will revolve for an instant entirely clear of the rail. The above discussion neglects the effect of the springs, which will be to increase the acceleration caused by gravity, and the resilience of the rail, which will cause it to rise to meet the flat spot. It is very questionable whether, on account of the very small time interval required for the wheel to pass the length of the flat spot,f there is an appreciable increase in the stress in the rail, except at the point of contact of the wheel with the rail. To increase the load on the rail a change in the vertical velocity of the load must be made; but at high speeds, when the effect of the flat spot is most detrimental, the time required to go the length of the flat spot is so small that the acceleration of the wheel and its load, even when augmented by the action of the springs, is so small as to be negligible. The real danger seems to lie in the metal of the running surface of the head of the rail; the metal here is under a high state of compression (see Figs. 146 and 147), which is momentarily relieved by the passage of the flat spot and then applied suddenly. When the flat spot is long enough so that the surface of the flat spot is brought in contact with the rail, a sensible change in the vertical movement of the load results and the load on the rail is increased. This is well shown by the following example given by Mr. L. R. Clausen,! of the Chicago, Milwaukee & St. Paul Railway: "Some time in the year 1900 we had an engine with a flat spot on rear right-hand driver 32 inches long and /? inch deep, which broke about 27 rails during one week's time (85-pound rails, not to exceed one or two years old) ". This flat spot was not apparent to the eye and was only detected by cen- tering the wheel and then measuring around it with a gauge. * E. E. Stetson, Railroad Age Gazette, December 4, 1908. f The present allowable length of flat spots in car wheels is 2| in. This rule was adopted by the Master Car Builders' Association in 1878. In 1909 the question of reducing the limit for freight wheels to less than 2| inches was considered by committees of the Master Car Builders' Association and the American Railway Engineering Association, but it was not then considered advisable to make any change in the rule. t Proceedings Am. Ry. Eng. & M. of W. Assn., 1909, Vol. 10, Part 2, p. 1158. Report on Flat Spots on Car Wheels. PRESSURE OF THE WHEEL ON THE RAIL 57 In the Railway Age Gazette of March 16, 1910, was reported 200 85-pound rails broken in 14 miles by a flat spot which had grown to a length of 6 inches, and a maximum depth of f inch. In the extreme cold weather experienced in the months of January and February, 1912, many tires failed by shelling out, and the following examples, taken from the same authority, are representative of the conditions ex- isting on lines in the Northern parts of the country during this period. Broken Rails January, 1912. January 7, 1912. January 14, 1912. January 20, 1912. January 24, 1912. February, 1912. February, 1912. Minnesota. Savanna, 111. South Dakota. New York State. New York State. Ohio. Flat spot 4 ins. long on a rolled- steel tire in passenger service. Flat spot 5j ins. long on steel-tired wheel in passenger service. Two steel wheels with flat spots, on different trucks of a dining Flat wheel on a fast train. Flat wheel on an observation car. Shelled-out steel-tired wheel; at end of run the flat spot was 9 ins. long. Flat spot on steel-tired wheel un- der a baggage car. 9 80-lb. rails in 3 150 rails. 500 rails. Nearly 100 rails. 15 rails. 960 rails in 200 miles. 50 rails in 70 miles. It is generally known by those familiar with the manufacture and use of chilled car wheels that only a very small percentage of them are evenly chilled. This, apart from weakening the wheel, also produces a lack of roundness tend- ing to cause pounding on the rail. The following information upon tests on the roundness of tread of chilled car wheels has been furnished by Mr. S. K. Dickerson, Assistant Superintendent of Motive Power, and Mr. H. E. Smith, Engineer of Tests, of the Lake Shore and Michigan Southern Railway Company.* To make these tests six pairs of wheels cast by different founders were selected. An axle with a wheel pressed on each end was placed in a lathe and the centers were firmly pressed. The wheels were then hand-turned. This done, the tread was divided into eight sections, each the same distance from the flat edge, and a specially constructed micrometer used to discover any variations in the roundness. All the testing was done with great care and precision. The tests are illustrated in Fig. 26. The dotted line in each diagram is a circle through that point on the tread having the smallest radius, and is assumed as the datum line. In plotting the diagram the variations from this datum line have been multiplied by five in order to emphasize the irregularity of the * Proceedings Am. Soc. for Test. Materials, 1910, Vol. X, p. 307. Unevenly Chilled and Untrue Car Wheels by Thomas D. West. 58 STEEL RAILS Fig. 26. —Irregularity in the Roundness of Present-day Chilled Car Wheels. (The Iron Age.) PRESSURE OF THE WHEEL ON THE RAIL 59 Fig. 26. — Continued. 60 STEEL RAILS tread. It is to be understood, however, that the figures given are the actual variations in the radii of the wheels from the datum circle. Owing to the present imperfect state of our knowledge on this subject it would seem desirable to determine experimentally the exact effect of the blow delivered by a flat wheel on the rail. Professor Benjamin* has designed an apparatus for such tests, which is shown in Fig. 27. The apparatus shown in the figure will permit of the continuous Fig. 27. — Apparatus for Measuring the Effect of a Flat Spot. (Benj; operation of one wheel upon one section of rail indefinitely and permit at the same time measurements of the effects of the blow. The truck is so supported that one wheel turns freely upon an idle pulley, while the other wheel on the same axle rests on a section of steel rail and in turning drives the latter by friction. The section of rail is bent to a circle, lying in a horizontal plane, and is firmly riveted and bolted to a supporting web, which is then fastened to a central hub of cast iron or steel. This hub turns freely on a vertical mandrel and is supported by a thrust bearing underneath. The rail and its attachments thus turn in a horizontal plane under the rotating car wheel. The portion of the rail immediately under the wheel is supported by friction rollers, which turn * Paper presented at Meeting of Western Railway Club, November 17, 1908. See also dis- cussion of Professor Benjamin's paper by H. H. Vaughan, American Engineer and Railroad Journal, December, 1908, and a further article by Professor Benjamin in the Railway Age Gazette, June 28, 1912, p. 1613. PRESSURE OF THE WHEEL ON THE RAIL 61 2 !£ ' flat spot RECORDING DEVICE *?T freely in a steel box or yoke. This latter forms a portion of the main casting supporting the hub of the rail, and this casting is bolted to a wooden pier so as to have a certain amount of elasticity. On the lower side of this casting and directly beneath the point of contact between the wheel and the rail is a hard- ened steel hammer, or ball, resting on a strip of soft metal. The soft metal is supported on a heavy anvil of cast iron and is fed slowly beneath the hammer by friction rollers. The truck being loaded with the desired amount of pig iron or other material, the wheels and their axles are rotated by means of a variable speed motor, and the energy of a blow delivered by a flat spot on the wheel is measured by the indentations of the strip of soft metal underneath the hammer. The amount of energy due to any given indentation can be readily measured by producing a similar indentation under a drop press. The curving of the rail in a horizontal direction is not sufficient to interfere with the action of the wheel and the energy of the blow is transmitted directly to the soft metal. A subcommittee of the American Railway Engineering Association have made an attempt to measure the force of the blow caused by flat wheels under working conditions. For this purpose an 80,000-pound capacity car was equipped with regis- tering devices to measure the compression of the car springs and a pair of wheels with flat spots was placed in one of the trucks. The position of the flat wheels, springs, and the recording device is shown in Fig. 28. The recording device con- sisted of an apparatus for measuring the maximum deflection of the springs. The springs were calibrated, and it was found that a load of 32,500 pounds applied to a nest of four springs produced a compression of one inch. R|EAR truck r|ear trujck ~> TRUE ■Qfi|WARD TRluCK 2 %" FLAT SPOT POSITIONS OF RECORDING DEVICES I z o z a. 0. IL p „ z o >i2 .> * -2 a § jg s * „ § oooo* I J | I ^ g ~ g ^ 1 S |i t? s J I- I oooo* cc _g t) a 3 § - J ooog? £ "®TT -"J OC09£ i- ® > Ja ^ 1 .g H ^ .2 g g I J I 3 « I '? -i 8 O C3 S g g « S 03 H B m t, " "fslT- °°° s " 3 ! "^ &S LL 74 STEEL RAILS 11. Electric Locomotives * In dealing with the electric locomotive the question of the excess balance necessary to counteract the reciprocating parts can be entirely neglected, and these machines, when properly constructed, would appear to have a more favorable action on the track than is the case with a steam engine of the same capacity. The low center of gravity possessed by the earlier locomotives of this type imposed, under certain conditions, a very severe duty on the rail, f In order to bring out the facts experimentally, the Pennsylvania Railroad Company, who were about to design locomotives for their tunnel entrance into New York City, constructed a special test track with apparatus for measuring side pres- sures upon the rail; they built sample locomotives of different designs and instituted a series of tests of electric and steam locomotives to determine their relative riding qualities at speed. It was found that all types of locomotives were practically steady at speeds under 40 miles per hour, but that above this speed marked differences appeared; that the steadiest riding machines were those with high center of gravity and with long and unsymmetrical wheel base. In other words, that the nearer steam-locomotive design is approached in wheel arrangement, distribution of weight, height of center of gravity, and ratio of spring-borne to under-spring weight, the less the side pressures registered on the rail head. table xvi. - - ELECTRIC and steam locomotives, comparison of weights AND CENTERS OF GRAVITY. (Gibbs.) Electric. Steam. Type 0-4-4-0 Pennsylvania. Experimental. 195,140 42.5 50 28 4-4-4-4 Pennsylvania. Experimental. 304,000 55 46.3 33.5 4-4-4-4 Pennsylvania. N. Y. Tunnel. 332,000 63.75 16.7* 30.2* 2-4-4-2 N.Y..N.H.&H. . Main Line. 202,000 37.4 2-4-4-2 Pennsylvania. Main Line. 176,600 73 22.7 33 4-4-0 Service Total weight of locomotive, running order in pounds Height, center gravity, complete Main Line. 138,000 Per cent of weight of running gear below springs to total weight Heights of center of gravity of running gear from rail, indies. 22.7 29 * Does not include motors as they are mounted in cab. Table XVI presents a comparison of weights and centers of gravity of modern electric locomotives and steam locomotives. Fig. 33 shows the Detroit River Tunnel Company's locomotive. * Seethe Railroad Age Gazette, Vol. XLVII, 1909, pp. 271, 319, 537, 881, and the Railway Age Gazette, Vol. XLVII, 1910, p. 829, for descriptions of electric locomotives given in this article. t Electric Traction by George Gibbs, report presented before the International Railway Con- gress, July, 1910. See also a very complete article " The Electrification of Railways " by George Westinghouse. Appendix No. 2. Data on Electric Locomotives of American Design, pp. 970-979. Trans. Am. Soc. of Mech. Engrs., 1910. Vol. 32. PRESSURE OF THE WHEEL ON THE RAIL 75 76 STEEL RAILS Fig. 34 illustrates the type of the Pennsylvania Electric locomotives which are used for handling the Pennsylvania Railroad trains into the New York station. This locomotive incorpo- rates many novel features in electric-locomotive design, and is the result of several years' cooperative development be- tween the Pennsylvania Rail- road Company and the Westinghouse Electric and Manufacturing Company. It is distinctively a high-powered machine, built for high speed operation. In wheel arrangement, weight distribution, trucks and general character of the run- ning gear, it is the practical equivalent of two American type locomotives coupled per- manently back to back. The connecting rods are all rotating links between rota- ting elements, and are thus perfectly counterbalanced for all speeds. The employment of this transmission permits the mounting of the motors upon the frame, secures their spring support, and, in common with the rest of the locomotive, the center of gravity at approxi- mately the same height above the rails, found desirable in the best high-speed steam experience. The same freedom of motion in the wheels and axles that is PRESSURE OF THE WHEEL ON THE RAIL 77 characteristic of the present steam locomotive is also obviously secured. It will be seen from Fig. 35 that the locomotive is an articulated machine and that each half carries its own motor and has four driving wheels, 68 inches hSoI r JGI H 1 DHf-f Mm 1 v • it''W^ si 1 i mm ! " H ! H^p^rafe mm V—-J6L- 78 STEEL RAILS in diameter, and one four-wheel swing bolster swivel truck with 36-inch wheels. In these locomotives the variable pressure of the unbalanced piston of the steam locomotive is replaced by the constant torque and constant rotating effort of the drive wheels, and the pull upon the drawbar is thereby constant and uniform. It might to the casual observer appear that by this arrangement of driving a return has been made to steam locomotive practice as regards \ counterbalancing difficulties, but it will, upon examination, be seen that nothing of the kind is true. There are no questions of unbalanced reciprocating weights involved, and all weights are revolving ones and directly counterbalanced. In Table XVII is given the general characteristics of the electric locomo- tives of this country. In determining the dynamic augment of the wheel load in the case of the electric locomotive, the effect of the counterbalance, which plays such an im- portant part in the pressure of the driver of the steam locomotive, can be entirely neglected. The other causes remain approximately the same, and by referring to Table XV (column 3), it is seen that the dynamic augment amounts to 26 per cent of the wheel load. Fig. 36 gives the load diagrams of electric loco- motives based upon this assumption. B.&O.R.R. 18 95 D — Dynamic Load per Wheel, pounds. /S = Static Load per Wheel, pounds. D =1.26 5, o tn o m L6^r PENNSYLVANIA R.R. 1909 9'- 4" i 7'- 2." >{ 9'- 9 " .1. 7 - 2? & & CO oo oo in O OO OO mo O if) Fig. OO O O OO O O OO O O OO OO o o oo oo O Q O O o o mo if) CQ 10 tO oo oo UT.Q vOK> i. — Typical Load Diagrams for Electric Locomotives. PRESSURE OF THE WHEEL ON THE RAIL 79 ft _ s. . «0 pJ^n 8 1 ||gJ«,«,S |8||| !*.E ~ ^ j: = S : : : coco ™ s |s assays 1 s ".6 i 1 .1.1 8 J Hill 1 I || * § |s s s s s : SS s 1 K 6 «o : 1 iy oo § »«;LJJ!| 1 |lj 9 H £j : S22g aoo § 1 1 13 .11 |: : : : : : S£ lillj S B § =8 | < 3 - 6 ^ 1_P^_J pounds %% °0 ^j oj — oi s = Static load per wheel, pounds 55 5 5 55 - - -- D = S + 10,000 where S is more than 15,000 ^ ^ „ qu) QW £> = 1.7 £ where S is less than 15,000 aV) ow Fig. 48. — Typical Dynamic Load Diagrams for Motor Cars. 86 STEEL RAILS PRESSURE OF THE WHEEL ON THE RAIL 87 In Figs. 51 and 52 are given examples of the cars in use on electric rail- ways, both for city service and on the longer runs of the interurban lines. " Single-end " Smoking and Express, Mail and Baggage Car. Seat ing capacity, 38. Weight of car body, about 34,000 lbs. Wheel base of trucks, 6'6". Weight of trucks, 21,460 lbs. Weight complete, about 38j tons. 62-ft. Buffet Observation Parlor Car. Scat ing capacity, 35. Weight of car body, about 44,000 11 Wheel base of trucks, 6'6". Weight of trucks, 21,460 lbs. Weight complete, about 44 tons. 51-ft. " Double-end " Special Parlor Car with Smoking Room. Seating capacity, chairs 26. Weight of car body, about 29,000 lbs. Seating capacity, seats 52. Weight of trucks, 20,322 lbs. Wheel base of trucks, 6'6". Weight complete, about 39 tons. Fig. 51. — Electric Railway Cars (Niles Car and Mfg. Co.). STEEL RAILS 51-ft. "Single-end," Two-compartment, Fast Interurban Car. Seating capacity, 52. Weight of car body, about 26,500 11 Wheel base of trucks, 6'6". Weight of trucks, 18,600 lbs. Weight complete, about 32 tons. — __,. ___ ^ ,ao - HI' In ~m i&. 48-ft. Center-vestibule, Arch-roof, Steel Prepayment Car. Seating capacity, 54. Weight of car body, 22,000 lbs. Wheel base of trucks, 6'4". Weight of trucks, 16,132 lbs. Weight complete, about 26 tons. 42-ft. Double-truck, "Single-end," Pay-As-You-Enter Car. Seating capacity, about 45. Weight of car body, about 16,000 lb Wheel base of trucks, 5'0". Weight of trucks, about 12,000 lbs. Fig. 52. — Electric Railway Cars (Niles Car and Mfg. Co.). PRESSURE OF THE WHEEL ON THE RAIL 89 Fig. 53 presents the typical dynamic load diagrams of this class of equipment. The dynamic augment has been taken the same for these cars and the motor cars as was used for the freight and passenger cars on steam roads. Weight of car and equipment 43,000 lbs. Weight of passenger load 15,000 lbs. (100 (a) 150 lbs.) WHEEL 33 DIA. 'ML Equipped with two motors weighing 34,000 lbs. each, both motors on axle of the rear truck. City Cars. j (j) WHEELS 36-DIA. (j) | (J) Interurban Passenger Cars. Weight of car body 35,000 lbs. Weight of trucks 24,000 lbs. Weight of motor equipment 19,000 lbs. Weight of passenger load 11,250 lbs. (75 pp|f>; r * *** Fig. 57. — Steel Tie after Four Years Service. (Am. Ry. Eng. Assn.) Fig. 57 shows a steel tie taken from the track that had been in service four years. Very little rust was found on the web of the tie and the bottom flange of this tie showed very little corrosion. There were no signs whatever of the tie failing in any respect. The cutting of the slots or holes in the web of the tie, as shown in the figure, has been abandoned, as it was found that with slag or stone ballast the holes with the web turned out were not necessary in order to keep the track from sliding sideways. SUPPORTS OF THE RAIL 93 The tie was smooth on the upper face where the base of the rail rests and showed very little, if any, wear. Providing the wear in years to come is no greater in proportion than it has been during the past four years, the tie would be good for 25 or 30 years. Fig. 59. — Hill Fastening on Carnegie Steel Tie. (Am. Ry. Eng. Assn.) 94 STEEL RAILS Fig. 58 shows the Carnegie steel tie with the wedge fastener. Carnegie Steel Tie with Hill Fastening. — (Fig. 59.) Approximately 100,000 of these ties have been installed in yard tracks at the Duquesne Plant of the Carnegie Steel Company. Hansen Steel Tie. (Am. Ry. Eng. Assn.) Hansen Tie. — (Fig. 60.) Five hundred of these ties were placed in the track, July, 1905, near Emsworth, Pa., on the Pennsylvania Lines West of Pitts- burg. A great deal of trouble was experienced with the insulation, also from the ties sliding transversely and longitudinally through the stone ballast, and the ties were in consequence removed from the main track in November, 1905, and placed in a passing siding. Universal Metallic Tie. — (Fig. 61.) The figure shows these ties in the Pennsylvania Lines tracks near Emsworth, Pa. The design is the trough type, being a 6- by 8-inch by 8-foot steel channel. Holes are cut in the web of the channel on each side of the rail, and this metal is bent up vertically on each SUPPORTS OF THE RAIL 95 side of a wooden block which fits in the channel under the rail. Clamps, fitting over the base of the rail and extending down vertically outside these bent-up portions of the channel, bind the block, rail and tie together. The clamp on the gauge side of the rail extends through the hole in the 'base of the channels about 4 inches into the ballast, giving an additional bond with the roadbed. A bolt, with a tapering head at one end and with a taper- ing washer at the other end, holds the connection tight. An insulating fiber is inserted between the rail and the clamp. The weight of this tie is 175 pounds. Fig. 61. — Universal Metallic Tie on Pennsylvania Lines. (Railway Age Gazette.) Fig. 62. — Snyder Steel Tie. (Am. Ry. Eng. Assn.) 96 STEEL RAILS Snyder Steel Tie. — (Fig. 62.) The illustration shows these ties in the Conemaugh yards of the Pennsylvania Railroad. There is also about one mile of these ties in use at Derry, Pa., on the same road, none of them being in the main tracks. The standard type of the Snyder tie consists of a steel shell T 3 e inch thick, 8 feet long, 7 inches wide, 7 inches deep, and with the bottom open. The interior of the shell is filled with a mixture of asphalt and crushed stone. In 20 of the ties the mastic had disintegrated and fallen out of the ends of the ties after four years service. With this exception the Snyder tie has given very satisfactory service in the tracks of the Pennsylvania Railroad at Conemaugh and Derry. Fig. 63. — Buhrer Combined Steel and Wood Tie on L. S. & M. S. Ry. (Am. Ry. Eng. Assn.) Buhrer Steel and Wood Tie. — (Fig. 63.) The figure shows the fourth or freight track of the Lake Shore and Michigan Southern Railroad, east of Toledo, tied with the Buhrer combined steel and wood tie. Early in 1907 the Carnegie steel ties on the Lake Shore and Michigan Southern Railroad were removed from the high-speed track. To care for the insulation the top flange of the tie was cut off and two wooden blocks bolted to the web of the tie for spiking strips and for the rail to rest on. These strips also rest on the bottom flange of the steel tie. Mexican Railway Tie. — (Fig. 64.) Practically the whole of the Mexican Railway system of 361 miles is laid with these ties. These ties weigh about 125 SUPPORTS OF THE RAIL 97 pounds, and cost $2.25. The ties are apparently giving excellent service. The axle load on this road, however, is not heavy on the light grades, and on the mountain grades, where axle loads as high as 50,000 pounds are employed, the 3 slow. 4 - -O HA LF LENGTH O F TI E. _ PLAN Fig. 64. — Mexican Railway Steel Tie. (Am. Ry. Eng. Assn.) Buhrer Concrete Tie. — (Fig. 65.) About 600 of these ties were used on the Pennsylvania Lines west of Pittsburg during 1903 and 1904 in stone ballast. Nearly 500 were subjected to heavy and high-speed traffic and the balance to medium traffic. The ties failed under traffic, the concrete breaking and crumb- ling off from the reenforcement. The ties were removed from time to time and by December, 1906, all had been removed on account of breaking. STEEL RAILS ■a - D \ 1 SUPPORTS OF THE RAIL 99 Fig. 66 shows the bottom or bearing surface of this tie, which illustrates how the concrete is left out at the center to provide against side motion. ■ s.. £ *^ m '* H >. >^ >- >-. >H >H g £ 1 1 1 II 1 Ills IIIIIII III III 1 £<2 o s ^^o QS^ llco Z °H g j — „o ||g?SS^ S« i | 8 28SK 3 : 1 6 1 g 1 I 1 Q |l 6| 1 1 SSSSSSh x -g I.U11.I.I °. s ^ 6606066 1 J 1 lllllll ShS fr £ 1 1 1 i ■? ■? Ill 1 1 1 f III £°? HHHHHKH = = « .> J g ';:.£.£ 1 K £ C J? |.2 ^^h,.-;^ -g-g-g g gw^J^c -'g~_: 1 1 I § ^ - '-a = ■i 1 V > D K fa ! I 6 5 PQ ■3 1 106 STEEL RAILS Probably no form of reinforced concrete tie has been made which is suitable for heavy and high-speed traffic. The real field of usefulness for the concrete tie appears to lie in its application in places where speed is slow and where conditions are especially adverse to the life of wood or metal. The steel tie seems much more promising, but the fact remains that most of the railroads in this country to-day are using wood, and, so far as the author is able to judge from present tendencies, are likely to continue to do so for some time. The question of a future timber supply for wood ties is a very important one. The railroads are rapidly exhausting the available timber near their lines and not only is the tie becoming dearer, but in many instances it is found im- possible to obtain a sufficient supply to meet the annual requirements of the road. The experience as set forth in a paper read at the American Forest Congress by Mr. L. E. Johnson, President of the Norfolk and Western Railway, is typical of most roads.* "Originally the country passed through by the railroad was well timbered. The first extensive depletion of timber land was on the first hundred miles adjacent to the seaboard, where the original timber was cypress and Virginia or loblolly pine. "Up to the year 1888 the road used a great many cypress ties, but such timber is no longer procurable. The second growth of Virginia loblolly pine in this district is very knotty, and, further, it is not suitable for crossties until it is treated to improve its lasting qualities. "All the balance of the road is in territory where both white oak and chestnut oak is indigenous, and up to quite recently all the crossties that have been needed have been obtained within moderate hauling distance from the railroad line. "The average requirements in oak ties per year for renewals are 310 per mile, aggregating, in round numbers, 800,000 ties per year for the entire road. At prevailing prices 800,000 ties cost per annum about $315,000, which is shown to be about 15 per cent over the cost of a like number ten years ago. This total is far below what some railroads less fortunately situated must pay for a like number." The general distribution and character of the original forests f of the United States are shown by Fig. 75. A glance at this discloses that five groups * Proceedings of The American Forest Congress, Washington, 1905, p. 265. t The Timber Supply of the United States, Kellogg. Forest Service, Circular 97. Original Forests, R. S. Kellogg, Vol. 2, pp. 179, 180. Report of the National Conservation Commission, Feb- ruary, 1909. SUPPORTS OF THE RAIL 107 of states embrace the natural timbered areas of the country, — the Northeastern states, the Southern states, the Lake states, the Rocky Mountain states and the Pacific states. Of these, the two groups last mentioned are occupied by forests in which practically all the timber-producing trees are coniferous, the 108 STEEL RAILS first three of both conifers and hardwoods. The earliest attack was upon the white pine of the Northeast, the original stand of which is almost entirely cut out. The Northeastern states reached their relative maximum in 1870 and the Lake states in 1890. The Southern states are undoubtedly near their maximum to-day, and the time of ascendency of the Pacific states is rapidly approaching. There will be no more shifting after the Pacific states take first place, since there is no new region of virgin timber to turn to. The percentage of the total lumber cut, furnished by the principal regions since 1850, according to census figures, is given in Table XIX. TABLE XIX. -GEOGRAPHIC DISTRIBUTION OF TOTAL LUMBER PRODUCT Year. New England &. Southern States. K! 1850 Per cent. 54.5 36.2 36.8 24.8 18.4 16.0 Per cent. 6.4 13.6 24.4 33.4 27^4 Per cent. 13.8 16.5 9.4 11.9 15.9 25.2 Per cent. 3.9 6.2 3.8 3.5 7.3 9.6 1860 1870 . . . 1880. . . . 1890 1900. .. . It is evident that at the present rate of consumption the available supply of the present timber used for ties, especially white oak and yellow pine, will be exhausted to a serious degree before many years, and that the railroads must consider the question of what course they are to pursue in the future. Under these conditions there are obviously two courses: First, the reduction of the amount consumed, which can be done by the substitution of other materials for wood and by the use of preservative methods for prolonging the life of the tie, which, by increasing its durability, will diminish the annual requirements for renewals; second, by the adoption of forestry methods, having for their purpose the proper care and management of the forests still remaining and the cultivation of new tree plantations. The question of forest preservation and perpetuation is beginning to receive attention in this country through the several State Bureaus of Forestry which have been established, and attention is given to forest preservation by these as well as by the National Government. It has been found that the most important need for most of the railroads at this time is definite technical information. It is not sufficient to know that SUPPORTS OF THE RAIL 109 timber supplies are being exhausted, but one should also know exactly what these supplies are, and what the rate of exhaustion is, and what the probable rate of regrowth is in any particular region upon which that particular road is depending. The need of such investigation is being universally felt, and has manifested itself in very striking form, as shown by the two meetings of the governors of Fig. 76. — Hunnewell Plantation (Catalpa). (Bureau of Forestry, Bulletin 37.) Average diameter 3.85 ins., 21st year. the various states, called by the President in May and December, 1908, in Washington, D. C. Many tree species * in the United States are adapted to a certain degree at least for the production of crossties. Notwithstanding this, in making the majority of railroad plantations only two species have been used. These two species are catalpa and black locust. Catalpa f has been planted for a great many years on a great variety of soils * Proceedings Am. Ry. Eng. and M. of W. i t Practical Arboriculture, J. P. Brown. , 1908, Vol. 9, p. 715. 110 STEEL RAILS and throughout a wide range of territory, and although many plantations have reached the age of twenty-five years or more,* so far as known, the trees in none of the plantations have reached a size suitable for crossties (Figs. 76 and 77). The black locust, although it is a rapid grower and thrives on a variety of soils, is so subject to the attacks of insects that trees seldom reach a sufficient size Fig. 77. — Farlington Forest (Catalpa). (Bureau of Forestry, Bulletin 37.) Average diameter 4.39 ins., 21st year. to make a crosstie. Trees which do reach this size are usually so weakened by numerous cavities made by the boring of the insects that the wood cannot be used with safety. Table XX shows that of the total number of trees planted, the locusts predominate, with the catalpa second; the results to date favor the former, although it is perhaps too early fairly to estimate the ultimate value of any of the plantations now under cultivation. * The Hardy Catalpa, Bureau of Forestry, Bulletin No. 37. The Farlington Forest, p. 15. The Hunnewell Plantation, p. 26. SUPPORTS OF THE RAIL 111 I M it i o definite knowledge obtained from results to date, but condi- tions are favorable for obtaining, within about 20 years, f ie- and posts amounting to double the erty up to present time. Expect to plant 10,000 trees in 1910. s'f.sf | I ost about 3,000 trees which were planted on low ground and did not stand the winter weal her. Balance are thrifty and look well. Cannot now estimate ultimate rom results thus far obtained no reliable estimate of ultimate value can be made. Present re- sults do not warrant additional planting. Catalpa is decided failure in arid and semi-arid districts of Texas. In the humid districts of Louisiana and Texas conditions do not seem favorable to its growth. 2 Eh 13 i-! fe l« 1 |s °. 8 Is 1 I* fj-2 § tfsl I 1 Is 8 Is I! 5 « 8 6 < S3 2,3 s 8 {{iff s - Q o STEEL RAILS s s fi I'l 1 Too early for any estimate as to ultimate value. Trees have se- cured Vr root growth and it is expected to cut all crooked and branched trees to ground line this winter. About 5,000 seed- lings failed to take root at time of planting. Total of 123 acres planted. Lati- tude of extreme coldness was unsuitable for catalpa, and prac- tically none of the trees grew. and experiment discontinued. Company has large holdings of mountain timber, also tracts in Eastern Virginia, containing Iml li soft and hard woods, original and second growths, which are being held, only mature timbers being Can give no estimate of ultimate No remarks. lift Is ll •J S § i 1 Is 1 £ g s § 8 S 1 1 If If o 6 6 do 1 1 1 1 1 1 1 Q 1 11 1 111 1 s « '11 I ^ ! H --3 ►". .2 S a 1 1 1 1 £ 1 5 1 ^ r * «■ * C3|| 5 i i - - 1 1 s g -S'd 1 £ SUPPORTS OF THE RAIL 113 Tree planting as such by railway companies has not been a very successful matter, and it is generally felt that the planting should be regarded as supple- mentary to other methods for securing a tie supply, particularly to the manage- ment of forest lands. There are, without question, large areas of timber in the South which can be obtained at a reasonable cost at the present time, and it seems to be very much more advisable to buy forest regions, or where cut-over lands are pur- chased, to encourage the growth of natural forest trees, rather than to go into extensive experiments for the planting of new trees. Forest planting in some cases may be desirable when a railroad has waste land for which it has no particular use. It is a good object lesson to the farmers, and if the plantations are successful they will net a fair return on the invest- ment and furnish a limited supply of tie and timber for the future. It should be observed, however, that it would not be practicable for the individual roads to plant enough trees to supply their timber requirements, and further the critical period of scarcity and high prices would come before any of the trees so planted would reach maturity. The information assembled by the Committee on Ties of the American Railway Engineering Association, in 1910 (Table XX), shows what has been done by the railroads in the way of tree planting; the situation is very little changed at the present time, and, in the opinion of those best able to judge, relief from this source is very uncertain. If the railroads wish to provide against future scarcity and excessive prices with any degree of certainty it will be necessary for them to actively engage in forestry operations, having for their purpose the management of mature timberlands and the cultivation and reforestation of the cut-over lands within the forest area. This is an individual problem with every road, but, generally speaking, it is the only sound policy which will provide for the future requirements fifteen or twenty years hence. Some of the railroads have now undertaken to preserve the timberlands which they acquired through land grants or otherwise. The Southern Pacific in northern California and southern Oregon still have quite large areas of good timber from which they can cut mature trees. The Northern Pacific has been cooperating with the government for some years with a view to finding how best to handle their western holdings, and provide a source of tie supply at the eastern end of their lines. In the East, the Delaware and Hudson have put about one hundred thousand acres in the Adirondacks under management.* * Timber Supply in Relation to Wood Preservation, E. A. Sterling. Proceedings, American Wood Preserver's Association, 1911, pp. 140-144. 114 STEEL RAILS While the great desideratum is the obtaining of a permanent source of supply of tie timber, the economic side of the problem must as well be considered. The application of actuarial methods to forestry is, despite the obvious difficulties about the assessments of the different factors used in making calcula- tions, the only correct way of estimating the financial position of timber crops as a commercial investment. The most profitable rotation is what should, both in theory and in practice, receive most consideration in the management of a forest. It is found by mak- ing various calculations, each as if for a single crop, in accordance with Faust- mann's formula, and ascertaining that particular rotation which shows the greatest profit by indicating the maximum productivity or largest capital value of land and growing stock. Faustmann's formula is as follows:* , _ F n +(T a xl.0y n - a ) + (T b xl.0p«- b )+ ■ ■ ■ (T o xl.0p»-«)-(Cxl.0y n ) g i.or-i 0.0/ where A = The productivity of the woodlands (as estimated by the net value of the timber crop, etc.); F n = The net income, free from cost of harvesting, yielded by the mature fall at the year (n); T a , T b , . . . T g = The net income, free from cost of harvesting, yielded by the thinnings at the years a, b, . . . q; p = The percentage or rate of interest which the woodlands are supposed to yield annually on the investment represented by their capital value; C = The cost of forming the crop originally, or of regenerating or replanting the area on the fall of the mature crop; g = The annual outlay for general charges (supervision, protec- tion, taxes, etc.). After determining the most profitable period of rotation, the amount of land required to produce a given amount of ties annually can be found. The cost per acre that can be paid for the land is determined as follows: The average annual charge, at present prices, for different kinds of ties may be taken as about 12.8 cents. * The Forester, Nisbet, Vol. II, p. 239, London, MCMV; and Economics of Forestry, Fernow, New York, 1902. SUPPORTS OF THE RAIL 115 This may be arrived at by the following relation. The discounted present value of an annual rental or return r obtainable for n years in all, the rate of interest being p, is expressed by the formula: r _ r(1.0p» -1) nr C(1.0p»x0.0p) 1.0p»x0.0p 1.0p»-l In the case of a white oak tie, C = $ .90, cost of tie in the track, and r = $ .14 annual charge. n = 8 years, life of tie; p = rate of interest, 5 per cent. The table given below shows the annual charge for different kinds of wood. White oak 14.0 cents annual charge Heart pine 12.5 cents annual charge Red oak, untreated 12.7 cents annual charge Miscellaneous 12.0 cents annual charge Assuming the life of a treated tie produced by the forest to be 12 years, the value of such a tie can then be expressed by the formula c r(1.0p»-l) l.Op-xo.op* where C = value of the tie; r = return or annual charge, 12.8 cents, obtainable 12 years in all; p = rate of interest, 5 per cent. Substituting these values in the formula, there results for the value of the tie $1.13. From this there must be deducted: Cutting • $0.10 Handling 0.05 Treatment 0.30 Transportation 0.20 Putting in track , . 0.15 Total $0.80 which leaves for the stump value of the tie $0.33. The amount of ties produced by the forest will depend upon the kind of trees grown and the location of the tract. An annual yield of three ties per acre should be expected under careful management in most cases of moderately rapid growing trees. This will bring in a return per acre of: 116 STEEL RAILS R = 3 ties at $0.33, less management and taxes $0.30 = $0.69, and the investment per acre which will give a five per cent return will be: The wasteful methods employed in cutting ties in the past have called forth many protests and suggestions as to how this waste might be checked. The Forest Service states in this connection: " The suggestions made for economy in the cutting of ties have been largely in the direction of preventing wasteful cutting. The manner in which they have been cut from trees has been largely determined by the ease and rapidity with which ties could be made, and by the knowledge that certain portions of a log were more serviceable for tie purposes than others. " Ties were usually made out of heart wood, using the best and only the straight, live trees. No attention was paid to the waste incurred by cutting off all the sapwood top section, by leaving dead trees, etc. But with the intro- duction of treated ties certain new developments in tie making have taken place. Treated ties allow the use of sapwood, of sawed dead timber, and of sawed ties, consequently tie forms which were altogether impracticable under the old methods are now within the field of possibility, and must be considered on their merits." In view of this Dr. von Schrenk has proposed a form of half-round tie which has been used extensively abroad (Figs. 78 and 79). The following description of the proposed form is taken from his excellent paper on Cross-Tie Forms and Rail Fastenings, f This form of tie is probably a more economical tie than the present rectangular tie used in this country, and, on account of its proved merits, should properly be considered as a possible substitute for the present form. If we consider the manner in which the load is distributed from the base of a rail resting on a 5-inch plate, which in turn rests on a tie 8 inches broad, we shall find that the lines of force acting from such a tie plate are distributed on the ballast as indicated in Fig. 80. * The cost per acre that can be paid for the forest land is based upon the annual charge of un- treated ties as representing the average outlay by the railroads for this material at the present time. The use of treated ties would probably reduce the annual charge per tie, but at the same time it must be borne in mind that owing to the rapidly increasing cost of the timber from which the tie is made, the annual charge for a treated tie will probably rise as high as the present figure for a natural tie, before sufficient time has elapsed for the treated ties to affect the general average. t Cross-Tie Forms and Rail Fastenings, Von Schrenk; Bureau of Forestry, Bulletin No. 50. SUPPORTS OF THE RAIL 117 Fig. 78. — Standard Prussian Ties of Baltic Pine. (Bureau of Forestry, Bulletin No. 50.) Fig. 79. — Standard Oak and Beech Ties on the French Eastern Railway. (Bureau of Forestry, Bulletin No. 50.) 118 STEEL RAILS Keeping in mind the desirability of an increased bearing surface on the ballast, it is suggested that a type of tie with a top-bearing surface of about Distribution of Pressure from Tie Plate Distribution of Pressure from Tie Plate in Half- in Ordinary Tie. round Tie. Fig. 80. — • Distribution of Pressure from Tie Plate. 6 *< .81. — Half-round Tie Proposed by the Forest Service. 6 inches and a base-bearing surface of anywhere from 8 to 12 inches will not only give a sufficient bearing surface for the rail, but will also give a much more stable track. Such a tie is shown in Fig. 81. Fig. 82 shows the 7 by 8-inch tie and tie with 6-inch top and 12-inch base, spaced as closely as is consistent with the proper use of the shovel or other tool employed to tamp the tie. Fig. 82. — Spacing of Half-round Ties. The comparative showing of rectangular 7 by 8-inch and 7 by 9-inch ties and of ties with 6-inch top and 12-inch base, spaced respectively at 11 and 10J inches, as shown in Fig. 82, is given in Table XXI. SUPPORTS OF THE RAIL 119 TABLE XXI. — COMPARISON OF RECTANGULAR AND HALF-ROUND TIES (Bureau of Forestry, Bulletin No. 50) New Tie, 6-inch Top, 12-inch Base. Distance between bearing centers, on both top and base tie, inches Increase in distance between bearing centers by use of ties of the new form, inches Total number of ties per mile Number of ties per mile saved by use of new form Total linear bearing on ballast per mile, feet Bearing surface on ballast per mile, with 8-feet length, square feet Gain in bearing surface by use of tie of the new form, square feet 3,242 426 2,161 352 2,376 19,008 3,520 2,816 " 2,816' 22,528 According to this table the number of ties of the new form required per mile is 352 less than with the 7 by 9-inch tie, and 426 less with the 7 by 8-inch tie, while the amount of bearing surface obtained is greater by 3,520 square feet than that obtained by the 7 by 9-inch tie, — an increase in bearing surface of over one-sixth. At the same time there would seem at first sight to be a con- siderable saving from the smaller number of ties, but in reality there is little difference in expense because of the larger number of feet, board measure, in the new tie. It now becomes necessary to consider the changed tie form from a lumber standpoint. Ties are now being cut from trees of all diameters from 9 inches upward. If cut but one from a cross section, they are usually termed pole ties. Most of these are rounded at the edge and squared on two sides (Fig. 83), with a required bearing surface of 6 to 8 inches. Pole ties are now cut from trees as large as 17 inches in diameter. Most of them are hewn, and in the hewing much of the outer portion of the tree is wasted. In larger trees also a great deal of timber is wasted, even when ties are split in the most economical fashion. In the majority of instances no wane is admitted for a first-class tie, so that logs less than 10 inches in diameter will not make ties of this class. This means that a great many tops are now left in the woods because they are too small. By adopting the half-round tie suggested above (and here emphasis Fig. 83. — Pole Tie. 120 STEEL RAILS ought to be laid upon the fact that ties cut according to this shape will all be treated) it will be possible to utilize a great many logs which now do not make ties, and also to cut a good many more ties out of the same amount of timber than under the present specifications. The cutting of ties of this new form will be essentially a sawmill proposi- tion. Where now there is a great deal of waste in hewing, if the log were sawed, it would mean the obtaining of several boards on the side. The number of boards to be sawed from a tree 16 inches in diameter, making two ties, will depend largely upon the value of the timber from which the ties are made. For instance, it will pay to make as many boards as possible out of a 16-inch, two-tie log of red oak or gum, while with timber like loblolly pine, the lumber of which has a low value, it will at present not pay to cut off many boards. In the case of such timber an extreme form of the half-round tie will be applicable (Fig. 84). The influence which the new tie form will have upon the size of trees cut for tie purposes ought to be a marked one. It certainly would discourage the cutting of pole ties to a very considerable extent. It would not pay to make a tie out of a small tree when by leaving it for a few years two ties could be made from the same tree. In other words, the present policy of cutting trees 11 or 12 inches in diameter would be found less profitable than cutting trees 16 or 17 inches in diameter. There is probably no other branch of the lumber industry in which so many small trees are annually destroyed and the possible regrowth of forests retarded to such an extent as in the manufacture of ties. The practice of sawing ties from logs is going to be more and more prevalent as the old feeling that a sawed tie is not worth having disappears. This feeling is already rapidly dis- appearing. It certainly will disappear entirely when railroad men realize that with a chemically treated tie it makes no difference whether it be sawed or hewn. With increasing permanency in the source of supply, it will pay more and more to put up small sawmills, which will saw ties and such lumber as may incidentally come to them. This will be particularly true in regions where there are rapidly growing tree species, such, for instance, as loblolly pine. The - Extreme Form of Half-round Tie. SUPPORTS OF THE RAIL 121 cutting of these trees will, moreover, make possible the use of large quantities of timber which now is practically wasted and from which the lumberman has no return. This is particularly true of tops. As the rail should be designed to have sufficient stiffness to enable it to distribute the load over a number of ties, allowing only such a proportion of the wheel load to come on each tie as can be safely carried, it will be necessary to determine the safe load that it will be proper to put on the tie. As a mean representing the average general practice, we may take in the following discus- sion a 7 by 8-inch by 8-foot 6-inch tie and a 7 by 9-inch by 8-foot 6-inch tie (see Table XXII). It would seem desirable also to consider the strength of the half-round tie. TABLE XXII. — SIZE OF TIES AND SPACING (Am. Ry. Eng. Assn.) Southern Penn. R.R L. &N B. &0 N. & W P. &R Penn. (S. W. Sys.). Lehigh Valley N.,C. &St. L D. & H. Co A., B. & A Cent, of N.J B.,R. & P C, C. &0 A. C. L Penn. (N. W. Sys.). D., L. & W Fla. East Coast... . C.,C.,C. &St. L... Hocking Valley.... L. S. &M. S Erie Long Island South. Pacific Union Pacific S. A. L N. Y., N. H. &H.. C. of Ga G.,H. & S. A Georgia M. &0 Norfolk Southern . . N. Y. C. &H. R... Great Northern. . . . S. P., L. A. & S. L. Northern Pacific. . . D. & R. G C..B. &Q 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8^ 7X7 and 9X8| 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! ■7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X7 and 9X8! 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X9X8 7X8X8 7X8X8 7X8X8 7X8X8 6X8X8 2880 2880 2880 2880 2816 2816 2816 2816 3300 3050 3040 2720 2720 3164 2816 3200 2900 3200 3200 C, R. I. & P St. L. &S. F Grand Trunk M.,K. & T Col. & Sou Maine Central C. &E. I C, I. & L El. P. &S.-W St. L., B. & M Ft. W. & D. C C. &N.-W C.,M. & P. S C.,M. & St. P C. I. &s St. L. S. W M. &St. L S. A. & A. P Rutland Mo. &N. Ark S. Fe, P. &P L. E. &W G. R. &I W. &L. E N. W. Pac Mo. Pac B. &M K. C.,M. & O Tenn. Cent C. G. W C.,H. & D M. C Bangor & Aroostook . N. Y.,0. & W M., J. & K. C a, st. p.,m.&o... D., S. S. & A 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X8X8 6X6X8 6X9X8 7X9X9 7X7X8 7X7X8 3200 3200 3200 3200 3200 3200 3200 3200 3000 3000 2992 2992 2992 2992 2992 2900 2880 2880 2816 2816 2816 2816 122 STEEL RAILS 14. Bearing of the Rail on the Tie The general tendency at the present time is more and more towards the use of tie plates. "With the introduction of the treated tie it is necessary to adopt some means to protect the wood from wear at the rail bearing on account of the longer life of the tie. The objections which have been made to tie plates were, first of all, that they buckled severely. This, however, has taken place only when the plates were too thin, and the following record of tests made of a prominent make of tie plate show that the present plates have ample strength to resist buckling (Table XXIII and Fig. 85). Most plates have been made with the idea of being anchored to the tie so as to prevent the communication of the motion of the rail to the plate. As a result, we have a large number of different forms of plates, provided with prongs, spines, or flanges on the bottom, which are pressed into the tie either by table xxiii.-test of McKEE tie plate the weight of the passing load or before the rail is laid (see Plate XXII). The chief objection which is made to plates at this time, par- ticularly in connection with the use of softer woods, is that not only do they not aid in preventing the wear of fibers, but they actually assist the rail to wear. This is well illus- trated in Fig. 86, showing a tie plate which has been in position on a loblolly pine tie for about four years. The constant rocking motion of the rail, which had become very marked as the spikes were pulled from the soft wood, had transmitted itself to the tie plate, and when a load passed over the rail the tie plate moved back and forth McKee Tie Plate. Loads as Applied, Te st No. 1, Tes t No. 2, Pounds. Deflec ion Inches. DeEect on Inches. 250 000 000 4,000 022 022 8,000 029 030 12,000 035 038 16,000 042 056 20,000 054 070 24,000 066 081 28,000 081 100 32,000 101 129 36,000 122 165 40,000 154 210 44,000 188 248 48,000 221 285 SUPPORTS OF THE RAIL 123 in unison with the rail. It was not long before the soft fibers of the loblolly- pine suffered under this treatment, and in the course of time so great did the abrasion and crushing of the fibers by the plate become that a considerable hole was made under the plate, in which water gathered. The plate gradually sank . Fig. 86. — Wear of Tie under Tie Plate. The upper illustration shows a Loblolly Pine Tie treated with Zinc Chloride, after four years' service in Texas. The lower illustration shows a longitudinal section through the spike hole of a Western Yellow Pine Tie after several years' service in Texas. (Bureau of Forestry, Bulletin No. 50.) down into this hole, as shown in the illustration. When the tie was removed it had disappeared in the wood, and the base of the rail was resting on the outer edges of the tie beyond the plate. This tie had been treated with zinc chloride. The water which gathered under the tie plate leached out the salt, and as a result decay started on both sides of the plate, as the illustration shows. The tie had to be removed, al- though the rest of it was perfectly sound (Figs. 87 and 88). STEEL RAILS % /$ v5 , -*-,~ N . i4 ft. ■2 ^^^hUhhP j— Fig. 87. — Section of Tie under Rail Bearing showing Wear and Decay, Fig. 88. — Section from Middle of Same Tie showing Entire Soundness. LOBLOLLY PINE TIE TREATED WITH ZINC CHLORIDE, AFTER FOUR YEARS' SERVICE IN TEXAS. (Bureau of Forestry, Bulletin No. 50.) SUPPORTS OF THE RAIL 125 The types of plates used in Europe are without exception flat plates.* Figs. I to 96 represent plates used by several European roads at the present time. Plan of Tie Pla Fig. 89. — Belgian State Railways, 105-lb. Rail and Tie Plate. (Am. Ry. Eng. Assn.) * See "The Question of Screw Fastenings to Secure Rails to Ties." W. C. Cushing, Proceedings Am. Ry. Eng. and M. of W. Assn., 1909, Vol. 10, Part 2. STEEL RAILS . 3.42" o 0.67" 5 , 138" 039 ,3|oflS" °1 Fig. 90. — Belgian State Railways, 115-lb. Rail and Tie Plate. (Am. Ry. Eng. Assn.) SUPPORTS OF THE RAIL 127 Intermediate liooK Plate. Fig. 91. — Kingdom of Wtirttemberg State Railways, Tie Plate. (Am. Ry. Eng. Assn.) 128 STEEL RAILS Fig. 92. — Bavarian State Railways, Joint Hook Plate. (Am. Ry. Eng. Assn.) SUPPORTS OF THE RAIL 129 Joint ' hook Plate.. - Kingdom of Saxony State Railroad, Joint Hook Plate. (Am. Ry. Eng. Assn.) STEEL RAILS Fig. 94. — Elsass-Lothringen State Railways, Tie Plate. (Am. Ry. Eng. Assn.) SUPPORTS OF THE RAIL SECTION THROUGH JOINT TIE 1 (T) \ O , l-3o' ■ w , l.46'j fe 1 1 4 , 1.89" A] oj2i 6.30" L° 3 . °i 95 ' ; 11.42" l iKV ,, 1 ,, Fig. 95. — Prussian State Railways, Tie Plate. (Am. Ry. Eng. Assn.) 132 STEEL RAILS Intermediate Wedge Plate Fig. 96. — Bavarian State Railways, Intermediate Wedge Plate. (Am. Ry. Eng. Assn.) The general tendency on the Continent has been toward adopting more and more rigidly flat plates, with firm fastenings. The almost universal adoption j,,,^,^.^ of this principle is very striking at the present day. On the French Eastern* the rail rests on the tie without metallic plates, except on very sharp curves (of 984.25 feet radius and under) . Plates of poplar or felt are placed under the rail, solely to protect the wood against the mechanical action of the base. These plates are compressed before being used, so that they will not be further compressed under the pressure of the rail. The plates are furnished 0.28 inch thick, and Fig. 97. — Wooden Tie Plate on French Eastern, the Compression brings them to 0.16 inch. * Bureau of Forestry, Bulletin No. 50, von Schrenk. SUPPORTS OF THE RAIL 133 The ties are adzed at the treating plant so that a place is left for this flat wooden shim. When the track is laid, the shim is placed in position (Fig. 97) and screw spikes are screwed into the tie. Their pressure holds the plate firmly between the base of the rail and the tie. In Fig. 97 the wooden tie plate is represented by the thin unshaded portion between the rail and the tie. It is exactly the width of the rail. In the course of time the motion of the rail wears out this shim, and a new one is substituted by giving the screw spike one or two upward turns. A new plate is then shoved in endwise and the screw is fastened. The length of life of one of the wooden shims on the main-line tracks, such as that of the French Eastern from Paris to Strassburg, is about one and one-half to two years. Dr. von Schrenk gives the theory upon which this wooden plate is used as follows : The principal function of the plate has been said to consist of prevent- ing the wear of the fibers of the tie immediately under the rail base. This wear consists in the actual breakage of the wood fibers under a grinding and tearing action rather than in crushing them. In considering the function of the tie plate we have three bodies to deal with: the tie, the tie plate, and the rail. Motion might conceivably take place either between the rail and the tie plate or between the tie plate and the tie. When a metal tie plate is used on the hardwood tie, and is successfully anchored in it, the tie plate and the tie act as one body, over which the rail moves back and forth. As soon as the tie plate loses its holding power, however, the chances are that when the rail moves across the tie the tie plate will oscillate back and forth in unison with the rail. This results in breaking the wood fibers under- neath the plate. Where a wooden plate is used, it adheres so closely to the wood that when the rail moves across the tie the wooden plate and the wooden tie are liable to act as one, even though the tie plate is not anchored to the tie. The Forest Service tests have not shown results favorable to wooden tie plates. While the tests have not been very thorough, they have been thought to throw much doubt on the efficiency of this form of plate. * For some years the question of a satisfactory fastening between rails and soft-wood ties has been a subject of continuous experiments on the Prussian Government railroads. The first investigations followed the general use of plain bearing plates, 7| by 6j inches (rolled steel) in size, shown in Fig. 98 a. * Fastening of Rails to Soft Wood (Pine) Ties, Organ fur die Fortschritte des Eisenbahnwesens, May 15, 1908, et seq. Translation appears in Vol. 10, Part 2, Proceedings Am. Ry. Eng. & M. of W. Assn., p. 1533. 134 STEEL RAILS It was soon discovered that on soft-wood ties, the small adhesion between the spike and the wood permitted the spikes to pull out to a more or less extent, and the loose rail, under the sudden applications of load, would quickly batter down the wood. Besides, the pressure on the tie not being uniform would produce a kind of convex wear in the wood, as illustrated in Fig. 98 b. Some improvement was obtained by the use of screw spikes, without, how- ever, entirely overcoming the abnormal wear and the consequent looseness Fig. 98. — Plain Bearing Plates, German Experiments on Tie Plates. and inefficiency of the structure (Figs. 98 c and d). The hook plate, shown in Fig. 99 a, was next tried. The hook, which was made to hold the outside flange of the rail, necessitated a plate somewhat longer on the outside than on the gage side, resulting in an uneven distribution of pressure on the wood and a condition as shown in Fig. 99 6. The bending of the screw spikes observed in this case was at first thought to be due to the lack of support of the head of the spikes on the far side from the rail flange, and, to r-medy this supposed defect, rail clips were introduced, giving the head of spikes a full support all SUPPORTS OF THE RAIL 135 around (Fig. 100 a). This arrangement proved to be much better than any- previous one, but still did not produce a satisfactory fastening. Fig. 100 b indi- cates clearly the manner of failure of these plates. Hook Plates, German Experiments on Tie Plates. It is evident that the plate hook, being rigid and incapable of producing any actual pressure against the rail flange, would cause all the stresses to be carried against the screw fastening, and as soon as this would wear in any of its parts the rail would become loose under the hook, and the shocks would CX Fig. 100. — Hook Plates with Clips, German Experiments on Tie Plates. begin their destructive work. Also, the direct pressure under the head of the spikes would tend to pull these out of the tie, and constitute another element of weakness to the general construction. The impossibility of fastening the rail with the same amount of holding power on both sides, besides the drawbacks enumerated above, led to the intro- duction of an entirely different system of fastening. The first set, or Group 1, of plates are shown in Fig. 101. These plates had a bearing on the ties of 90 square inches as against 80 square inches in the largest previous plate, and were fastened to the ties by means of four screw spikes absolutely independent of the rail fastening. The rail was in its turn STEEL RAILS fastened to the plate by means of two bolts and clips, these being independent of the tie fastening. The clips were made so as to be capable of adjusting the gage of the track by being reversible, and also of such a shape as to take up and transmit hori- zontal forces at the base of the rail to the shoulders provided for in the tie plates. In this manner the upward forces would be resisted by all the screw spikes, and similarly all the horizontal forces would be taken care of. Spring . r< 12% ---320."?™- > IT of ( )( 1° f AJjLA * IiiwmM ErLFN Ljp. ° 1 Fig. 101. — Group 1, German Experiments on Tie Plates. washers were provided under the head of the screw spikes and the rail-fastening nut. Eighty-three of these plates were put in service in 1898 and removed from the tracks, together with the ties, in 1907 for examination. The tie wear was found to be very slight and very uniform under the base of the plate, varying from a minimum of 0.14 millimeter (iJ-g- inch) to a maximum of 0.19 millimeter (-j-jj-g- inch), except in a few cases where spikes had become loose and caused an increased as well as an irregular wear. n 250 m !S -, LTo J \ °T nil III, „ 1 00 i ill ||lJ : l YL° \ ( 6\ Fig. 102. — Group 2, German Experiments on Tie Plates. Sand, however, was found between the ties and plates, and this might have caused even this slight wear. The rail seat in the tie plate had worn to about the same extent (maximum iwo inch). No other sign of deterioration was observed. The second series of tests, Group 2 (Fig. 102), was carried on under con- ditions similar to those for Group 1. The main difference between these plates SUPPORTS OF THE RAIL 137 and the plates of Group 1 lies in the size of the bearing surface over tie, being about 70 square inches for Group 2 plates as against 90 square inches for Group 1 plates. On removal of the plates, it was found that the wear of tie developed the same uniform wear as in the previous group. The slight wear gave the impres- sion of being purely compression, there being no indication whatever of side dis- placement. As a matter of fact, after the screw spikes had been removed the plate had to be knocked off with a hammer. Sand was found under the edge of only a few plates. The screw spikes used on these plates were 4f inches by f inch and had a deeper thread than those of Group 1. In spite of the smaller bearing of this plate, as compared to Group 1, the amount of tie wear was actually smaller, and the fastening generally more satisfactory. Center of Rail^l 10" - 3 /8 ' 4 7 A Fig. 103. — Group 3, German Experiments on Tie Plates. Condition of test in Group 3 (Fig. 103) was similar to the previous tests in Groups 1 and 2. The main difference in this case consisted in the sloped top of the tie plate, which gave the rail a desired amount of inclination toward the gage side. This arrangement brought the center of rail closer to the outer edge of the tie plate by about 10 millimeters (f inch). Screw spikes used were similar to those in Group 2, but with a somewhat better grip, the holes having been drilled smaller. To increase the rigidity of the fastening, double spring washers were employed on all the screw spikes. The tie wear was smaller than in any previous instance. The gage of the track was measured frequently and found to remain practically unchanged. The spring washers, which had shown some failures when used singly, were found in this test to have their original elasticity unimpaired. This design of tie plate, however, failed in a few instances, as shown at "a," Fig. 103, which would seem to indicate that a greater stress was carried against this point than in the other arrangements. 138 STEEL RAILS It is clearly evident from the behavior of plates of Groups 2 and 3 that the wear of ties is not at all directly proportional to the extent of the bearing surface of the tie plate, but depends more upon the rigidity of the fastening. In the case under consideration, the most important point developed is the necessity of rigidly fastening the tie plates to the ties in order to preserve the life of the tie. 15. Fastening of the Rail to the Tie In this country the ordinary nail spike is generally used for fastening a rail to a wooden tie. The most important objections to the spike are: first, in Fig. 104. — Short Leaf Pine Tie, after 2 Years' Service, cut through Spike Holes. (Bureau of Forestry, Bulletin No. 50.) the soft-wood tie the spike does not hold with sufficient firmness to keep the rail securely to the tie; second, in driving the spike into the softer woods the fibers are broken to an unusual extent (Fig. 104). As a result they do not withstand lateral pressure of the rail, and consequently the spike hole is rapidly increased to such an extent that the spike no longer holds. Water collects in the enlarged hole and decay sets in (Fig. 105). Table XXIV * compares the holding force of a common spike (Fig. 106), weight 165 spikes to 100 pounds, with that of the common screw spike (Fig. 107), similar to those used on the French and other continental railroads, weight 85 spikes to 100 pounds. * Holding Force of Railroad Spikes in Wooden Ties, Forest Service, Circular 46. SUPPORTS OF THE RAIL 139 L ^ 1,1 - -! - :t ; -J t>' • till : -"JS 1 VJ-> Iv-"^ vtfi _iL*-*^ a^i^jp^ gii^'^-i^U%^^^*~ - Cross Section through the Spike Holes of Short Leaf Pine Tie, treated with Zinc Chloride, Texas. (Bureau of Forestry, Bulletin No. 50.) TABLE XXIV.- • HOLDING FORCE OF COMMON AND SCREW SPIKES (Forest Service, Circular 46) Number of Tests. Condition of Wood. Force Required to Pull Spike. of Spike. Average. Maximum. Minimum. White oak: Common spike 5 5 Partially seasoned Pounds. 6,950 13,026 1.88 Pounds. 7,870 14,940 6,160 11.050 5 8 Oak (probably red): Common spike 4,342 11,240 2.61 5,300 13,530 3,490 ...do 8,900 28 26 Loblolly pine: Common spike 3,670 7,748 2.11 6,000 14,680 2,320 ..do 4,170 12 14 Green ....do Hardy catalpa: Common spike 3,224 8,261 2.56 4,000 9,440 2,190 6,280 11 11 Green ....do Common catalpa: Common spike 2,887 6,939 2.42 4,500 8,340 2,240 5,890 4 5 Chestnut: Common spike 2,980 9,418 3.15 3,220 11,150 ....do 7,470 STEEL RAILS t-%"- Fig. 106. — Common S Fig. 107. — Common Screw Spike. Tables XXV and XXVI are taken from "Studies of the Stability of Rail- way Tracks," by Jules Michel,* and give the holding power of hook and screw spikes. TABLE XXV. — PULLING FORCE NECESSARY TO PULL OUT FOR 0.20 INCH IN A HOOK SPIKE AND A SCREW SPIKE BURIED 4.13 INCHES IN THE WOOD (Jules Michel) P.L.M. Hook S P.L.M. Screw Spike. Poplar Larch Baltic fir, creosoted Beech, treated with sulphate of copper. . Oak American cypress Pounds 992 1,598 Pounds 4,454 5,291 5,732 Figs. 108 and 109 present examples of early screw fastenings. Fig. 108. — Screw Spike used by Grand Duchy of Baden State Railways (1860). * Revue Generate des Chemins de Fer, July, 1884, and June, 1893. SUPPORTS OF THE RAIL NORTHERN Fig. 109. —Early French Screw Spikes (1863). TABLE XXVI. — FORCES NECESSARY FOR EXTRACTING BY 0.20-INCH SCREW SPIKES 0.79 INCH AND 0.91 INCH IN DIAMETER WITH THREADS OF 0.39-INCH AND 0.59-INCH PITCH, SUNK 4.14 INCHES IN WOOD OF VARIOUS SPECIES AND AGES (Jules Michel) Diameter of Screw Date of Spike. Trial. Pitch of Northern New Wood Currently Employed in Tracks 1875 0.79 0.79 0.79 0.79 0.79 0.79 0.91 0.39 0.39 0.39 0.49 0.59 0.49 0.49 5,733 9,481 10,143 9,923 10,584 11,576 12,844 12,458 0.59 0.59 0.55 0.55 0.55 1881 July, 1884. 1889 Rolled screw spikes, 24 trials. 1889 1889 1891 7,640 11,378 1889 13,010 12,348 0.67 Wood Having Been 9 Years in Track 0.79 0.79 0.39 0.49 10,143 11,576 Fig. 110 shows a machine used on the Atchison, Topeka and Santa Fe for preparing ties for screw spikes. Wooden dowels as shown in Fig. Ill are screwed into the ties.* Table XXVII gives the cost of equipping a mile of track with screw spikes, the estimate being based on work actually done on a section of track five miles in length on the Illinois division of the railway. * Railroad Age Gazette, December 24, 1909. 142 STEEL RAILS Fig. 110. — Machine Preparing Ties for Screw Spikes. (Railroad Age Gazette.) Hole Tapped Plug in Place Dressed for Tie Plate Completed Rail Fastening Fig. 111. — Showing Application of Screw Spike on A. T. & S. Fe R. R. (Railroad Age Gazette.) TABLE XXVII. — ONE MILE OF TRACK WITH SCREW SPIKES AND DOWELS 12,000 spikes at 2.7 cents each : $ 324 6,000 tie plates at 21 cents each 1,260 Boring ties for, and driving, 24,000 dowels, at 1 cent each 240 24,000 wooden dowels at 1| cents each 360 Driving screw spikes (per mile) 150 Total $2,334 ONE MILE WITH CUT SPIKES 12,000 spikes $ 127 6,000 tie plates at 21 cents each 1,260 Driving cut spikes (per mile) 150 Total $1,537 * Apparently the French railways were about the first in Europe to begin the use of the screw spike (tirefond) as a rail fastening, and it is to-day uni- versally employed by the large systems (Fig. 112, Table XXVIII). * For a very full discussion of the subject, see " The Question of Screw Fastenings to Secure Rails to Ties," W. C. Cushing, Proceedings Am. Ry. Eng. & M. of W. Assn., 1909, Vol. 10, Part 2, p. 1456. SUPPORTS OF THE RAIL 14a Fig. 112. — French Railways — Rail Fastenings. (Am. Ry. Eng. Assn.) 144 STEEL RAILS TABLE XXVIII. — FRENCH RAILWAYS — RAIL FASTENINGS (Am. Ry. Eng. Assn.) Railway. Number and Position of Screw Spikes at Each End of Tie. Type of Rail Used. Screw Spikes. Number of Ties Used per Rail. Joints. Name. - J~ hi 2oj Q 3 g :: : : Arrangement. No. Bolts. tDe Paris a Lyon et a la Meditei ranee 6194 4544 3631 3083 2445 2380 1812 2 inside and 2 outside 2 inside and 1 outside 1 inside and 1 outside 2 inside and 1 outside 2 inside and 2 outside 2 inside and 1 outside alter- nating with 1 inside and 2 outside 2 inside and 1 97 lb. T. •B.H. T. ♦B.H. &T. T. T. •B.H. 16^22 11.62 to 5.91 5.71 4.72 5^52 4.73 4.72 to 5.32 0.79 0.87 0.91 0.91 0.55 0.59 0.54 0.62 0.65 0.67 0.49 0.39 0.49 0.49 0.31 12 to 14 per 36' 17 per 39.37' 25 per 59' 14 to 16 per 36' Square and suspended Square and suspended Square and suspended Square and suspended Square and suspended 6 De L'Ouest * B.H. means Bull Head. t Mr. Cartault. As-istani Chief Engineer often surpasses 15,432 to 17,637 pounds. The above are all the important French n i>ak or beech, the i. extraction reaches ai TABLE XXIX. — GERMAN RAILWAYS — RAIL FASTENINGS (Am. Ry. Eng. Assn.) Kind of Tie Plate. Number and Screw Spikes at Each End of Tie. Type WciL'hl of Rail Screw Spikes. Number o Tie- !"sed Joints. Name of State Railway. ids Q 3 III '--- Arrange- No. of Bolts. Wiirttemberg Hook plate. Hook outside Hook plate. Hook inside At joints. Hook plate. Hook inside At intermedi- outside 2 inside and 1 outside 2 inside and 1 outside Hook spikes 1 insifle and 2 outside T. 92.74 T. 14.21 16.15 5.12 and 5.91 5.32 6.69 0.79 0.79 0.59 0.59 0.39 Suspended Suspended 6 Hook plate. Hook inside 2 inside and 1 outside 87.7 T. 16.58 6.5 0.79 0.59 0.39 Suspended Baden (2) Use hook an 73 T. atcsancl screw fBava •ianSt te Rys. Suspended 4 and 6 Elsass-Lothringen Hook plate. Hook outside 1 inside and 1 outside 91 T. 16.54 5.91 0.87 0.65 0.39 23 and 24 Square and suspended 6 Prussian (3) Hook plate. Hook outside 2 outside and 1 inside 91 T. 16.54 5.91 0.87 0.65 0.39 19 and 24 per 49.2' Suspended 6 (1) Use screw spikes on main tracks, and hook spikes on secondary tracks. (2) Use steel ties almost exclusively. Use wooden ties on bridges with steel floor beams, in tunnels and for insulated joints in electric signal districts. (3) In tunnels use cast-iron chairs, wooden wedges, spikes, and trenails identical with Midland Ry., England. " Hook spikes are now only used on lines of minor importance." SUPPORTS OF THE RAIL 145 The German railways did not adopt this style of fastening as early or as generally as those of France, and the use of the hook spike is quite widespread. In 1899, the general employment of the screw spike on all lines of the system was prescribed for the Prussian Government Railways (Fig. 113, Table XXIX). Fig. 113. — German Railways — Rail Fastenings. (Am. Ry. Eng. Assn.) Same design of Screw Spike \ I by the Wurttemberg, Bavarian and Baden State Railways as is shown for the Saxon. 146 STEEL RAILS >L The common hook spike used in the United States has been often severely- condemned by writers in the technical press, and the readers have been usually led to infer that it is employed everywhere in Europe, which is seen from the above not to be the case. Indeed, the screw spike in Great Britain is almost as rare as it is in the United States, at least on the large systems, the only one SUPPORTS OF THE RAIL making use of it being the London and North Western, and that only partially (Fig. 114, Table XXX and Plate XIII). All of the large railway systems in Great Britain use the double-head rail, held in position in large cast-iron chairs by wedges, and consequently the fasten- ings are for securing the chairs to the ties. For the purpose of fastening the chairs to the ties, the almost universal plan is to use two iron or steel spikes and two wooden trenails. The spikes are not pointed, and are driven into previously bored holes. Instead of the trenails, the London and North Western Railway makes use of two screw spikes, which resemble those of the Belgian State Railways. TABLE XXX.— ENGLISH AND SCOTCH RAILWAYS — (Am. Ry. Eng. Assn.) RAIL FASTENINGS Number and Kind of Fastenings per Chair. Spikes. Trenails. Railway. Length Head. Head. 'of Shank. Total Length. Length of Top Cone Top Diam. Inches. Diam. Point. Lancashire & York- Great Eastern 2 spikes and 2 trenails 2 spikes and 2 trenails *2 spikes and 2 trenails *2 spikes and 2 trenails *2 spikes and 2 trenails J|2 twisted spikes and 2 trenails 2i-inch bolts through ties TT2 spikes and 2 screws t6i 1 Inches. 1 Inches. 1 §61 Inches. 2 Inches. Inches. Great Northern .ii • n-inn- in' hi ln"l North British J6 6 1A 1 ft 2 2 2ft if if if a North Eastern li 3 o London & North t6 11 \i * Has short mileusre of chairs secured by two f-inch bolts thro t Illustrated by Fig. 1 of Fig. 114. t Illustrated by Fig. 2 of Fig. 114. § Illustrated by Fig. 3 of Fig. 114. 11 Illustrated by Fig. 4 of Fig. 114. On the Forth Bridge the North British Ry. uses flat-botton II The twisted spikes are to be abandoned for plain ones. ;ened to longitudinal beams by wood sc Diameter of hole required for this ecrew fi" - Screw Spike deduced from European Practice. (Cushing.) STEEL RAILS Fig. 115 shows a design of screw spike deduced by Mr. Gushing from European practice. The form of the thread seems to have little influence upon the holding power of the screw spike. Table XXXI gives the resistance for threads of right-angle form and those of isosceles triangular form. TABLE XXXI RESISTANCE OF SCREW SPIKES HAVING DIFFERENT THREADS (Jules Michel — Revue Generate des Chemins de Fer, June, 1893) Dimensions of Screw Spikes. Isosceles Thread. Right-angled Thread. Remarks. Screw Spikes 0.79 inch in diameter. New tie. Pitch of 0.39 inch Pitch of 0.59 inch Pitch of 0.49 inch 11,687 pounds 12,458 pounds 13,010 pounds 12,039 pounds 12,513 pounds 13,561 pounds Average of 4 trials. Average of 4 trials. Average of 4 trials. Screw Spikes 0.91 inch in diameter. Pitch of 0.49 inch 13,424 pounds 13,424 pounds New tie. Screw Spike 0.79 inch in diameter. Pitch of 0.39 inch Pitch of 0.49 inch 10,253 pounds 9,923 pounds 11,576 pounds Ties 9 years in service. Ties 9 years'in service. Screw Spikes 0.91 inch in diameter. Pitch of 0.49 inch 11,246 pounds 11,025 pounds Ties 9 years in service. The proof that the screw spike is not a thoroughly efficient rail fastening lies in the devices which have been invented to assist it in its work, — the square plug, the Collet trenail, the Thiollier helical lining, and the Lakhovsky screw and case.* The main objection to the Collet trenail is its size; it is illustrated in Figs. 116, 117, and 118 with a screw spike and the wooden plug commonly used on French railways for repairing old holes. The difference in size is large, the Collet trenail being If inches in diameter outside the threads. This cuts away a considerable portion of the critical part of a tie, and is considered by many engineers to weaken the tie too much. The plug is only about an inch square. Nevertheless this screw dowel is largely used in Germany. The Collet trenail has been tested from its inception by the Chemins de Fer de l'Est, but the square plug illustrated in Fig. 117 is preferred. The wooden screw, often made of elm, cannot be put in place without removing the tie from * Lakhovsky trenail, Revue Generate des Chemins de Fer. Paris, 1909, Vol. XXXIII, pp. 324-327. SUPPORTS OF THE RAIL 149 %"ScrswSpiKe Chermnde Fe.r de UEsf Fig. 116. — French Screw Spike. (Am. Ry. Eng. Assn.) Square Wooden Plug used for repairing old holes. Fig. 117. — Wooden Tie Plug used on French Railways. (Am. Ry. Eng. Assn.) 150 STEEL RAILS Col le' "■ I r&no i f _ somefirr les used as substitute for square 01 ug the track, and it frequently splits. The ties on the Chemins de Fer de 1'Est are principally oak and beech. Figs. 119 and 120 illustrate pine ties with dowels in place. The diagrams of Figs. 121 and 122 give the comparative resistance to vertical pressure of screw spikes with and without dowels. The Thiollier steel helical lining is being experimented with as a sub- stitute for the Collet trenail, and the Lakhovsky screw and steel casing (Bulletin of the International Railway Congress, March, 1907) are considered worth trying by the Chemins de Fer de l'Est, de 1'Etat, and de Paris a Orleans. From its greater holding power, the verdict of the engineers of the French, Belgian, and German railways is that the screw spike is superior to the hook spike, because they consider it very important to hold the rail fast to the tie. On the other hand, the British railways do not seem to find the screw spike necessary for their large and heavy chairs, and they use creosoted ties, as well as the Continental lines; but the holes for their spikes are bored in advance. According to our present knowl- edge, the amount of bearing surface the tie plate has upon the tie is ap- parently not the determining factor in providing against wear. The question of securing the plate firmly to the tie is fully as important as the size of the plate used, and in selecting a proper unit stress for the bearing on the tie it is evident, therefore, that the area of the bearing surface cannot be con- Fig. 118. — Collet Trenail. (Am. Ry. Eng. Assn.) SUPPORTS OF THE RAIL 151 sidered without taking account of the kind of fastening employed to hold the plate to the tie. Fig. 119. — Cross Section of Pine Tie through Dowel. (Bureau of Forestry, Bulletin No. 50.) Fig. 120. — Three Ties of Baltic Pine on the Prussian State Railways, Berlin, showing the manner in which screw dowels appear in the tie when ready to be shipped. (Bureau of Forestry, Bulletin No. 50.) STEEL RAILS 16000 - r 15000- -D p 11^ JE : i "IE s NEW 13000- 12000- - II000-- 1 / / / r > '/ >/ *' 7 V ^ / V / / / I) <>7 4000 - - "4 & V 4 i £i / / / , / / / V / / / a 5 OS 10 .1 06 .08 ■1 3 12 14 .16 VERTICAL DISPLACEMENT - INCHES - Comparative Resistance to Vertical Pressure of Screw Spikes in Pine Ties, Old and New, with and without Dowels. (Bureau of Forestry, Bulletin No. 50.) / / / / / / / / / / / *y / $/ / / / 6/ / / ■y / 1 W 1 / ^ 1 & 1 1 >/ / 1 1 <■■/ / rf / / / / / / / < / / 1 / 1 1 / / 1 / / 1 // / // / // .02 .C 4 6 .C 8 2 4 6 .0 z D 4 8 16 Fig. 122. — Comparative Resistance to Vertical Pressure of Screw Spikes in Beech Ties, Old and New, with and without Dowels. (Bureau of Forestry, Bulletin No. 50.) SUPPORTS OF THE RAIL 153 In the case of a white-oak tie, where the spike holds well and the life of the tie is comparatively short, the ordinary working stress of the timber to resist crushing at right angles to the grain may probably be safely taken in propor- tioning the strength of the tie. With soft woods, however, which offer less resistance to the spike pulling loose, and which, when treated, possess long life, the ordinary working stress of the wood has little application to the bearing under the tie plate unless some means are used to secure the plate firmly to the tie. As will be seen in the discussion of the Supporting Power of the Tie (Article 19), one of the weakest points in the support of the rail lies at the bearing of the tie plates on soft-wood ties, even when the normal crushing value of the wood is taken as is done in the calculations. It is thus of considerable impor- tance that with a soft-wood tie a more secure fastening than the ordinary spike be used to hold the tie plate firmly to the tie. With the increase in density of traffic there has developed a growing tendency for the rail to creep or move in the direction in which the traffic moves. On account of the joint ties being spiked through slotted holes in the joint, these ties move with the rail, with the result that correct spacing of the adjacent ties is not maintained. To overcome this difficulty there have been devised numerous devices for anchoring the rails to the ties. These are generally fastened to the base of the rail and bear against the side of the tie; when employed in sufficient numbers they are fairly efficient in preventing the movement of the rail* 16. Strength of the Tie Assuming the tie to be in good condition and free from decay, we have now to determine the strength of the wood of which it is composed. Let us first examine the kinds of woods used in the United States. * Some recent literature on this subject is as follows: Kunze, W. — Das schienenwandern, ursache und abhilfe. 2,500 w. 111. 1909. (In Glasers annalen fur gewerbe und bauwesen, Vol. 65, p. 122.) Considers cause of creeping in rails and devices for its prevention. Schldssel, L. — On the working loose of screws when used as rail fastenings, 21 p. 111. 1907. (In Bulletin of the International Railway Congress, Vol. 21, p. 3.) Concludes that wedge fastenings should be substituted for screw fastenings. Tex, K. den. — Creeping of rails in the direction of the trains. 800 w. 111. 1911. (In Bulletin of the International Railway Congress, Vol. 25, p. 292.) Use of rail anchors. 2,000 w. 111. 1911. (In Railway Age Gazette, Vol. 51, p. 125.) Considers tendencies in the creeping of rails and forms of anchors most successful in over- coming it. Wirth, Alfred. — Die schienenwanderung und ihre verhiitung. 10,000 w. 1909.- (In Zeit- schrift des Osterreichischen Ingenieur — und Architekten — • Vereines, Vol. 61, p. 317, 333.) Discussion of rail creeping at some length, considering theory and prevention by rail-fastening devices. 154 STEEL RAILS The following statements are based on the number of ties bought rather than on the number actually used. For all practical purposes, however, the two are identical, because the purchases in twelve months are an accurate index of consumption for a corresponding period. Table XXXII shows the number and value of the different kinds of ties purchased by the steam and street railroad lines in the United States in 1906, and contrasts the purchases of steam railroad companies in 1905 and 1906. TABLE XXXII. — NUMBER AND VALUE OF TIES PURCHASED BY STEAM AND STREET RAILROADS IN THE UNITED STATES IN 1905 AND 1906 (Forest Service, Circular 124) Steam railroads, 1905. Steam railroads, 1906. Street railroads, 1906.* Number. «. Aver- YaTue !fe. Number. Value. Value per Tie. Number. Value. Aver- Oaks 34,677,304 18,351,037 6,962,827 3,633,276 4,717,604 3,483,746 (t) 3,060,082 1,713,090 590,852 (tt (t) 791,409 $19,072,517 7,707,436 3,083,644 1,198,981 2,264,450 1,149,636 $0.55 .42 .44 .33 .48 .33 41,532,629 17,538,090 6,416,867 6,706,222 4,646,763 4,988,585 3,909,500 2,430,236 2,037,002 725,346 553,838 258,030 1,734,517 $21,256,518 8,905,009 3,044,446 2,782,967 2,132,984 1,813,500 1,673,359 837,217 576,896 248,844 210,458 76,833 661,501 $0.51 .51 .47 .41 .46 .36 .43 .34 .28 .34 .38 .30 .38 3,825,245 1,303,120 666,575 542,340 1,942,212 115,911 60,105 146,623 21,196 523,283 900 115,357 93,550 $2,021,534 662,736 265,670 227,425 862,958 48,635 24,668 52,344 6,072 287,328 360 74,219 64,643 $0.53 South'rnpinest Cedar Douglas fir. . Chestnut Cypress Western pine. Tamarack. . . . Hemlock Redwood Lodgepole pine White pine . All others. . . . .51 .40 .42 .44 .42 1,101,630 565,320 118,170 .36 .33 .20 .36 .29 .55 64 343,662 .43 69 Total. . 77,981,227 $36,585,446 $0.47 93,477,625 $44,220,532 $0.47 9,356,417 $4,598,592 $0 49 T I' mi I'MU includes \vl t Included in southern >aas in iwua. ,ne, lodgepole pine, and western pine. The purchases of ties reported by the steam railroad companies in 1906 exceeded those of 1905 by more than 15,000,000. Nearly one-half of this excess was oak. The purchases of cedar ties showed a decrease of about one- half million, due possibly to the sharp demand for cedar poles, which operated against the production of ties. Douglas fir ties nearly doubled in quantity, and both cypress and hemlock increased by a large percentage, but tamarack purchases fell off more than one-fifth and chestnut about 1.5 per cent. Oak, the chief wood used for ties, furnishes more than 44 per cent, nearly one-half of the whole number, while the southern pines, which rank second, contribute about one-sixth. Douglas fir and cedar, the next two, with approxi- mately equal quantities, supply less than one-fifteenth apiece. Chestnut, cypress, western pine, tamarack, hemlock, and redwood are all of importance, but no one of them furnishes more than a small proportion. SUPPORTS OF THE RAIL 155 Table XXXIII shows, by kinds, the number and cost of the cross-ties pur- chased by steam and electric railroads in the United States in 1907. Table XXXIV gives a comparative statement showing the number of cross-ties purchased by the steam and electric railroads during the years 1910, 1909, 1908, and 1907. Of the total purchases of cross-ties during 1910, 139,596,000, or 94.2 per cent, were made by steam railroads, while electric railroads purchased 8,635,000, or 5.8 per cent. The steady increase in the number of cross-ties reported as purchased for new track is noteworthy. The total for this purpose in 1910 was 22,255,000, as against 16,437,000 in 1909, 7,431,000 in 1908, and 23,557,000 in 1907; the total for 1910 exceeding that for 1909 by 35.4 per cent, for 1908 by 199.5 per cent, and nearly equaling that for 1907, the largest ever recorded. Largely as a logical result of the greater demand for cross-ties during 1910, the average cost per tie at point of purchase advanced to 51 cents, the same figure reached in 1907, as compared with 49 cents in 1909 and 50 cents in 1908. In 1910, as in preceding years, oak was the principal kind of wood used for cross-ties. The number of oak cross-ties formed 46.1 per cent of the total for 1910, as compared with 46.2 per cent in 1909, 42.8 per cent in 1908, and 40.2 per cent in 1907. A substantial increase in 1910 over 1909 is shown in the number of southern pine cross-ties reported; the increase in the cut from this species over 1909 being 22.8 per cent, as against an increase of 20 per cent in the total number of cross-ties reported from all woods. Douglas fir also showed for 1910 over the preceding year a larger increase, namely, 28.2 per cent, than the increase in the total purchase from all woods. On the other hand, chestnut, cedar, and cypress, with increases over 1909 of 17.1 per cent, 7.8 per cent, and 17.6 per cent, respectively, were bought in relatively smaller quantities. While the bulk of the cross-ties were cut from the six woods mentioned dur- ing each of the four years and while combined they contributed 85.5 per cent of the total in 1910, 85.3 per cent in 1909, 86.5 per cent in 1908, and 87.2 per cent in 1907, a remarkable and significant showing in connection with the figures for 1910 is noted with reference to certain woods which hitherto have been utilized as cross-tie material to only a very limited extent. The increase in the number of cross-ties over 1909, reported as cut from elm, was 451.7 per cent; gum, 328.8 percent; birch, 323.3 per cent; spruce, 121.5 per cent; and mesquite, 114.9 per cent. A very large percentage of the cross-ties cut from these woods were given some preservative treatment, thus increasing their life to or beyond that of untreated cross-ties made from the more commonly used or standard cross-tie 156 STEEL RAILS TABLE XXXIII. — CROSS-TIES PURCHASED BY STEAM AND ELECTRIC ROADS OF THE UNITED STATES IN 1907 (Bureau of the Census, Forest Products No. 8) Total. Steam Railroads. Kind. Hewed. Sawed. Number. Total Cost. cSl per Tie. Number. Total Cost. Aver- Cost T P fe. Number. Total Cost. Aver- age Cost Tie. Total... 153,699,620 $78,958,695 $0.51 112,309,246 $56,522,768 $0.50 31,776,434 $17,020,882 $0.54 Oaks 61,757,418 34,215,081 14,524,266 8,953,205 7,851,325 6,778,944 5,019,247 4,562,190 2,366,459 2,030,982 666,916 474,455 4,499,132 32,985,122 18,434,198 6,818,869 4,473,960 3,772,048 3,099,439 2,515,798 2,254,617 807,241 1,198,497 332,984 193,606 2,072,316 0.53 0.54 0.47 0.50 0.48 0.46 0.50 0.49 0.34 0.59 0.50 0.41 0.46 51,169,478 25,629,749 1,436,258 7,941,152 4,922,831 5,695,640 3,206,754 4,144,127 2,283,675 884,552 666,916 289,624 4,038,490 26,774,251 13,100,589 590,754 3,987,035 2,337,697 2,552,381 1.576,457 2,083,646 770,969 507,154 332,984 106,528 1,802,323 0.52 0.51 0.41 0.50 0.47 0.45 0.49 0.50 0.34 0.57 0.50 0.37 0.44 6,929,572 7,415,686 12,366,640 396,891 889,420 884,915 1,626,330 340,618 79,256 406,519 4,033,150 4,569,060 5,884,822 190,322 426,523 453,058 835,895 137,481 34,796 224,525 0.58 Southern pines Douglas fir. . . Cedar Chestnut Cypress Western pine. . Tamarack. . . . Hemlock Redwood Lodgepole pine White pine All other 0.62 0.48 0.48 0.48 0.51 0.51 0.40 0.44 0.55 131,671 308,916 53,041 178,209 0.40 0.58 TABLE XXXIV.— CROSS-TIES PURCHASED BY STEAM AND ELECTRIC ROADS OF THE UNITED STATES DURING THE YEARS 1910, 1909, 1908, AND 1907 (Bureau of the Census) 1910 1909 1908 19J7 Kind of Wood. Number. Cost at Number. Cost at point of N imber. Cost at purchase. Number. Cost at purchase. Total 148,231,000 875,889,000 123,751,090 860,321,000 112 467,000 S56,282,000 153,703,000 S78,959,000 Oak 68,382,000 2o.jh4.ooo 11. i>2:i, Olio 7,760.1)111) 7,:joj,oiiii .3,3.10,000 3,103,000 4,iil2,ooo 3,40s, 000 2,10.3.01)0 1,621,000 798,000 773,000 548,000 499,000 429,000 393,000 238,000 178,000 134,000 476,000 37,731,000 13. :i30,ooo .3,317, 3,716,000 3,430,000 2,390,000 2,U7«,ooi> 2,058,000 1,063,000 1,262,000 754,000 351,000 346,000 220,000 251,000 201,000 170,000 121,000 156,000 71,000 266,000 57,132,000 2I,3.\.3. I 9,067.000 0,020,001) 6,777,000 4,589,000 3,311,000 (i, 7 l .)7,ooii 2,012,000 2.OS.S.0OO 378,000 195,000 158,000 99,000 225,000 556,000 92,000 487,000 120,000 62,000 962,000 29,062,000 48 11,112,000 21 3,754,000 7 2,947.000 8 • 3,085,000 8 1,902,000 3 1,356,000 4 3,619,000 3 865,000 3 1,108.000 198,000 69,000 55,000 46,000 109,000 237,000 32,000 224,000 117,000 . . 39,000 385,000 1 110,000 ;,.,o, oiiii 9X.S.IIIIII 11,-4.000 172.000 457,000 023,0011 OH3, 120,0110 871,000 202,0110 102.01)11 131,000 05,ooo 111,000 707, 11 1,000 ol.s.ooo ' 31.000 846,000 24,653,000 11,50!), 000 3,500,000 3,0.s2,ooo 4,028,000 1,320,000 2,010,000 1,573,000 1,179,000 444,000 117,000 86,000 68,000 24,000 66,000 335,000 38,000 247,000 61,757,000 31,21,3,000 11.53.3,01)0 7,S51,(HI0 ,s, 05 l.i ii in 6,780,000 4,502,000 5,1119, 000 2,307,000 2,032,000 15,000 52,000 32,9S4,000 Cedar 4,474,000 We-tern pine 2,516,000 104,000 475,000 Lod.iex.le pine 667,000 333,000 21,000 684,000 4,328,000 SUPPORTS OF THE RAIL 157 woods. The growing scarcity of these last-mentioned woods, however, tends to increase their cost and accounts largely for the introduction of substitutes cut from cheaper species. The drift in this direction is clearly brought out by a comparison of the figures relating to treated cross-ties during the past four years. In 1907 the number of cross-ties reported as having been given some preservative treatment was 19,856,000; in 1908, 23,776,000; in 1909, 22,033,00; and in 1910, 30,544,000; the number for 1910 showing an increase over that for the preceding year of 8,511,000, or nearly 39 per cent. The question of tie preservation is becoming more and more important as the demand for tie material increases and the traffic requirements become more exacting. So long as plenty of white-oak ties could be secured, the necessity for tie preservation was not felt; but with the constantly increasing use of pine and other less decay-resistant woods, it has become a vital economic question. The railroad companies have met the problem by establishing treating plants in various parts of the United States and by laying experimental tracks with treated ties to determine the efficiency of the several preservatives under vary- ing conditions.* Table XXXV, prepared by the Forest Service, f gives the results of an elaborate series of tests upon the strength of treated and untreated pine ties. In outlining the plan for these tests two divisions were made, dealing respectively with the effect on the strength of timber of the preliminary proc- esses of steaming, superheating, vacuum, etc., commonly employed in the preservation of wood, and the effect of the preserving materials themselves. The tests were confined to sapwood, and were made on small pieces taken from the tie, and also on full-sized ties. The effect of the preliminary processes was determined on both green and seasoned timber. ' Both green and seasoned timber were also used in deter- mining the effect of preservatives. The preservative fluids included only creosote t and zinc chloride. The material for the experiments was railroad ties 11 feet long. One 8-foot section of each tie was put through the particular treatment, and the untreated section, 3 feet long, was used for control test pieces. From each tie 12 pieces were taken, 4 from the control section and 8 from the treated section. All of these pieces were 2 inches by 2 inches in cross section and 36 inches long, with one side parallel to the direction of the annual rings * Experiments with Railway Cross-ties, Forest Service, Circular 146. t Experiments on the Strength of Treated Timber, Forest Service, Circular 39, by W. K. Hatt. X The treatment was essentially the "Rueping" process, although this name is not used in tha circular. 158 STEEL RAILS TABLE XXXV. — EXPERIMENTS ON THE STRENGTH OF TREATED TIMBER (Forest Service, Circular 39) EFFECT OF STEAMING AND PRESERVATIVE TREATMENTS ON THE STRENGTH OF GREEN LOBLOLLY PINE [Specimens, 2 by 2 inches; air-dried before tests! Cylinder Conditions. Strength. per Inch. Moisture. Specific Gravity (dry). Steaming. h Static. Im- 8 § «a ■6 I i I 2 a 1" < S3 H fl 6 --, =- 1 l fe f 6 & 2 6 2 3 H 6 1 Hrs. Lbs. sq. in. °F. Lbs. per eu.it. Per Per Per Per Per Per Untreated wood =100 percent. f 4 20 25V 92.81 93.11 93.81 93.2 7.5 6.5 13.8 13.4 0.558 J. 646 Steam, at various pressures 4 HO -m 99.8104.3 102.0 102.0 7.5 7.0 12.7 12.2 .553 .571 ^4 40 2i n 94.6 99.0107.7100.4 6.0 6.0 13.6 12.4 .525 .534 14 50 296 94.51 96.4|l03.5l 98.1 6.5 6.5 13.7 12.5 .514 • 508 Creosote, injectedat 150°F. Steamed wood = 100 per cent. under a pressure of 100 pounds per square inch. . . 4 20 258 25.4 81.6 79.9 102.4 88.0 6.5 6.0 13.2 .663 Zinc chloride: 2.5 per cent solution. . . 4 20 249 87.4 92.8 113.8 98.0 6.5 6.0 12.8 13.7 .530 .534 3.5 per cent solution. . . 4 20 246 97.4 95.2 92.7 95.1 7.5 7.0 13.1 13.5 .538 .539 5.0 per cent solution. . . 4 20 24(i 99.8 96.7 78.9 91.8 5.5 6.0 12.3 13.4 .510 .506 10.0 per cent solution. . . 4 20 255 100.1 100.4 74.8 91.8 8.5 8.5 13.2 13.5 .582 .612 Physical Characteristics and Average Strengths of the Air-dried Untreated Wood Moisture per cent Weight per cubic foot (dry) pounds Rings per inch Modulus of elasticity pounds per square inch 1,1 Bending strength at elastic limit Bending strength at rupture • Compression strength parallel to grain Compression strength at right angles to grain Shearing strength radial to grain 13.4 33.6 SUPPORTS OF THE RAIL 159 TABLE XXXV. — Continued [Specimens full-sized ties; seasonec treated and reseasoned before tests] Cylinder Conditions. Strength (static). Spike Pulling. 8 Force Re- § Steaming. Bending Compression. g Treatment. H „; Pull Spike. 8. i 3 I 1 £ 1 1* 3 . - 2 ■So (33 < < 1 a a 6 s •s Hrs. Lbs. per sq. in. °F. Per Per Per Per Per Per Lbs. cu. ft. Untreated wood = 100 per cent. f 4 10 237 99.2 79.3 91.1 89.9 118.5 110.7 4.9 38.0 1 4 20 258 93.7 78.4 99.1 90.4 103.6 109.4 5.2 37.3 Steam, at various pressures — i 4 30 274 87.8 83.4 92.7 88.0 100.1 96.5 5.3 37.9 It 40 286 88.4 78.1 74.6 80.4 93.0 77.9 5.2! 37.8 50 295 69.1 60.6 74.4 68-0 80.4 70.3 4.8 1 36.1 r 2 20 257 82.4 81-9 87.1 83.8 97.9 93.7 5.1 38.1 Steam, fo various periods 1 4 20 258 93.7 78.4 99.1 90.4 103.6 109.4 5 ? 37.3 1 6 20 256 87.5 78-8 92.0 86.1 83.0 79.0 4.6 36.7 110 20 256 77.0 75.5 73.2 75.2 84.1 76.8 4.8 36.7 Zinc chloi ide, 2.5 per cent solu- 4 20 258 74.7 65.1 68.6 69.5 75.3 73.8 4.3 41.5 Creosote, 28 pounds per cubic 4 20 257 69.5 61.2 60.1 63.6 68.2 68.1 4.6 65.3 Physical Characteristics and Average Strengths c : Untreated Wood Moisture '. per cent (approximate) Weight per cubic foot (air-seasoned) pounds Rings per inch Modulus of elasticity pounds per square inch Bending strength at elastic limit Bending strength at rupture Compression strength parallel to grain Compression strength at right angles to grain (rail-bearing) " Spike pulling — common spike Spike pulling — screw spike 1,568,000 3,429 6,458 4,452 503 3,598 7,748 TABLE XXXV. — Continued EFFECT OF STEAM AND CREOSOTE ON THE STRENGTH OF SEASONED LOBLOLLY PINE [Specimens, 2 by 2 inches; tested immediately after treatment] Cylinder Conditio: Steam, at various pressures Creosote, injected at 150° F. under a pressure of 100 pounds per square inch. . Soaking, wood previously treated with creosote in- jected at 150° F. under a pressure of 100 pounds per square inch Per Per 'Ood = 100perce 92.6|106.4|124.0|107.7 6 70.91 55.ll 72.9' 6" " Steamed wood = 100 per ( 97.1|102.2|110.7|103.3 7 Seasoned wood = 100 per cent. 81.0| 78. 4| 82.0| 80.4 7 Soaked untreated wood = 100 per cent. 19.20 139.4 160.4 . 6.06 5 21.6 . 1X.< 5 78.1 . Physical Characteristics and Average Strengths of the Untreated Seasoned Wood Moisture per cent Weight per cubic foot (dry) pounds Rings per inch Modulus of elasticity pounds per square inch 1,6 Bending strength at elastic limit " " " Bending strength at rupture " " " Compression strength parallel to grain " " " Compression strength at right angles to grain " " " Shearing strength radial to grain " " " TABLE XXXV. — Concluded 9,444 4,819 Untreated wood = 100 per cent. 117.0 I 130.0 Weight (air-seasoned). Control. Treated. Physical Characteristics and Average Strengths of the Untreated Wood Moisture per cent Weight per cubic foot (dry) pounds Rings per inch Modulus of elasticity pounds per square inch 1 Bending strength at elastic limit " " " Bending strength at rupture " " " Compression strength parallel to grain " " " Compression strength at right angles to grain " " " Shearing strength radial to grain " " " 8,760 4,956 SUPPORTS OF THE RAIL 161 and the other at right angles to it. After the bending tests had been made on these pieces, smaller pieces, 2 inches by 2 inches in cross section and 4 inches long, were cut from their ends and used for the compression and shearing tests. In any tie the test pieces were taken out according to Fig. 123, variation being allowed only to secure clear pieces. The test pieces from each tie were marked consecutively from 1 to 12. The untreated pieces, marked 1 and 2, were used for control-impact tests, and those marked 3 and 4 for control-static tests. The treated pieces, marked 5 and 6, were used for impact tests; those marked 7 and 8 for static tests. The 4_ 2 3 CONTROL TREATED \ / S S 2 6 /O 3 7 " 9 IZ 10 II Fig. 123. — Control Plan — Creosote Tie Tests. treated pieces, marked from 9 to 12, were similarly tested, but were resoaked, if necessary, to bring them back to the degree of moisture found in the control pieces. Ordinarily the steaming process did not decrease the moisture content of the wood, in which case tests on resoaked pieces were not required. In addition to the tests on small pieces, the strength of full-sized ties in bending and in compression, both parallel and at right angles to grain, was obtained, as well as the capacity of the wood to hold a spike. The ties used were 8 feet long. The entire tie was treated and afterwards tested in full size. In the bending tests under a static load, the ties were supported on a span of 80 inches and loaded at the third points of the span. Short sections of the ties were used for tests to determine the resistance against compression parallel to grain, against compression at right angles to grain (which is similar to that produced on a tie by the base of a rail), and against the force withdrawing a spike. In the tests of compression at right angles to grain, the width of the tool equaled that of the base of an 80-pound A. S. C. E. rail. The force necessary to cause the yielding of the wood was measured. Both screw spikes and common spikes were driven into the tie, and the force necessary to pull them out directly along their length was meas- ured. Any common spike was driven but once, since it was found that the resist- ance against pulling diminished when the spike was redriven into new wood. The weight of the tie before treating, after treating, and at the time of test was determined. The physical characteristics of the wood, such as per 162 STEEL RAILS cent of sap, rate of growth, shakes, knots, and moisture content, were also recorded. Impact tests were made on certain of the full-sized ties. In general, it was found that the influence of the various factors may be determined by both static and impact tests. The results of these tests form a body of evidence from which the fol- lowing general conclusions may be drawn: (1) A high degree of steaming is injurious to wood in strength and spike- holding power. The degree of steaming at which pronounced harm results will depend upon the quality of the wood and its degree of seasoning, and upon the pressure (temperature) of steam and the duration of its application. For loblolly pine the limit of safety is certainly 30 pounds for 4 hours, or 20 pounds for 6 hours. (2) The presence of zinc chloride will not weaken wood under static load- ing, although the indications are that the wood becomes brittle under impact when treated with solutions above 3.5 per cent concentration. (3) A light treatment with creosote will not weaken wood of itself. Since, apparently, it is present only in the openings of the cells, and does not get into the cell walls, its action can only be to retard the seasoning of the wood. The Committee on Wood Preservation of the American Railway Engi- neering Association in its report at the March, 1910, Convention of the Asso- ciation presented the following conclusions based on the best data available at the time on the strength of treated timber: (a) High steaming will diminish the strength rapidly. (6) Treating with strong solution of zinc chloride will render the timber brittle, perhaps because of free acid in the solution. (c) Creosote is inert. (d) Seasoned timber treated with light doses of creosote is as strong as the original timber. Tables XXXVII and XXXVIII give the results of tests of the Forest Ser- vice on a number of woods, and Table XXXIX shows the unit stresses recom- mended by the Committee on Wooden Bridges and Trestles of the American Railway Engineering Association. The great variation in strength, which is noticeable in timber of the same species, makes it necessary to accept with caution the result of a limited number of tests representing the average of the species. One of the most troublesome factors influencing the strength of wood is the amount of moisture in it. SUPPORTS OF THE RAIL 163 TABLE XXXVI. — ACCOUNT OF TEST MATERIAL USED IN TABLE XXXVII SUMMARY OF MECHANICAL TESTS ON THIRTY-TWO SPECIES OF AMERICAN WOODS (Division of Forestry, Circular 15) of Me- clianii al Tests. Localities and Number of Trees from Each. Cuban pine (Pinus heterophylla.) Shortleaf pine t l'niiis echinata.) Loblolly pine (Pinus taeda). Whil Spruce pine i'ma-aialaa , Bald cypress (Taxodium distichur White cedar (Chamaecyparis thyoides.) Douglas spruce (Pseudotsuga taxifolia.) White oak (Quercus alba.) O vercup oak (Quercus lyrata.) Post oak . . (Que r.) Cow oak . . (Quercus michauxii.) Red oak (Quercus rubra.) Texan oak (Quercus texana.) Yellow oak (Quercus velutina.) Water oak (Quercus nigra.) Willow oak (Quercus phellos.) ' '" lllio, II . Waici fnrkon ' II I I Nutmeg hickory (Hicoria myristicaeformis.) Pecan hickory (Hicoria pecan.) Pignut hickory (Hicoria glabra.) White elm (Ulmus amerieana.) Cedar elm (Ulmus crassifolia.) White ash (FraxiL Green ash (Fraxinus lanceolata.) stpla ■Iain (22); uplands (6); hill district (6); .ting uplands (6), South Carolina, coast sippi, low coast plain (2); Louisiana, low a, gravelly soil (7); sandy loam (6); Texas, low i (6); Georgia, uplands (1); South it plain (6). Alabama, coast p Carolina, coast (.,. Alabama, uplands (4); Missouri, low hilly uplands (6); Arkansas, low lulls' uplands 'Hi, I e>.a -, uplands Mi;. Alabama, mountainous plateau (8); low coast plain (6); Arkansas, level flood plain (5); Georgia, level coast plain (6); South Carolina, low coast plain (7). Wisconsin, clay, uplands (51; sandy soils (4); sandy loam a",): Michigan, level drill lands (3). Wisconsin, drift (5); Michigan (3). Alabama, low South Carolina -i plaii le barren (6); river bottom (4); Louisi- , border of lake (4); Mississippi, Yazoo bottom (3); upland (3). ississippi, low plain. Alabama, ridges of Tennessee Valley (5); Mississippi, low plain (7). Mississippi, low plain (7); Arkansas, Mississippi bottoms (3). Alabama, Tennessee Valley (5); Arkai bottom (3). Alabama, Tennessee Valley (4); Arkai bottoms (3); Mississippi, low plain (4). Alabama, Tennessee Valley (5); Arkansas, Mississi bottom (2).* Arkansas, Mississippi bottom. Alabama, Tennessee Valley (5). Mississippi, low plain (4). Alabama, Tennessee Valley (5); Arkansas, Mississippi hotioiu 1 3 i; Mississippi low plain i ! i. Alabama, Tennessee Valley (5); Arkansas, I l.oiioin (3);] [ississippi, low plain (3). Mississippi, alluvial plain (3); limestone (J Miss sippi, low plai ., bottom. Arkansas, bottom. Mississippi, bottom. Arkansas, bottom (3); Mississippi, low plain (4). * These two should probably be classed as Southern red oak. They were collected before the distinction Note. — The values for specific , moisture below 15 per cent; the n_ at its influence on specific gravity ere given refer to "dry" wood of test material, i.e., wood containing variat jffect has therefore not been taken into account, but more careful experime such low per cent is so small that it may be neglected for practical purposes. STEEL RAILS In Table XXXVII all values except those for the Southern pines have been referred to 12 per cent moisture, which may be said to be the lightest average moisture content of seasoned wood. TABLE XXXVII. — RESULTS OF TESTS IN BENDING — AT RUPTURE SUMMARY OF MECHANICAL TESTS ON THIRTY-TWO SPECIES OF AMERICAN WOODS (Division of Forestry, Circular 15) [Pounds per square inch] No. Species. Number of Tests. Single Test. Lowest Single Test. 10 Per Tests. I.nweM 10 Per cent of Tests. Average Tests. o°Trats n within 10 Per cent Proportion of Tests within 25 Per cent of Average. 1 2 Reduced to 15 Per cent Moisture Longleafpine 1,160 390 330 650 95 170 87 41 218 216 256 57 117 40 31 153 257 187 75 14 25 72 37 30 18 87 10 118 17,800 17,(100 14^00 11,100 12,900 16,300 9! 100 20^300 19,600 23^000 16,500 19,500 15,000 16,000 16,000 17,300 23,300 20,700 18,000 19,500 16,600 18,300 25,000 14,000 19,200 15,000 16,000 14,400 2^900 5,000 3,900 4,600 3,100 3,100 2,300 3,500 3,800 5,700 4,900 5,100 3,300 5,700 8,200 5,100 5,800 3,200 5,000 5,700 5,300 5,300 7,000 6,700 5,600 11,100 7,300 6,600 5,000 5,100 5,100 14,200 14,600 12,400 13,100 10,100 12,300 13,600 11,700 8,400 12,000 18,500 14,900 15.300 12,500 15,400 16,900 14,600 15,700 13.800 15,600 20,300 19,700 17,300 19,300 15,600 18,100 24,300 13,600 17,300 14.200 16.000 12,700 8,800 8,800 7,000 8,100 5,000 4,900 5!000 4,000 4,100 6^00 7,400 9^100 10,000 5,700 7,200 5,400 6,900 9,400 7,900 5,400 8,700 8,100 10,300 11,500 7,300 8,500 6,300 5,100 6,000 10,900 11,900 9,200 10,100 7,900 9,100 10,000 7,900 6,300 7,900 13,100 11,300 12,300 11,500 11,400 13,100 10,800 12,400 10,400 12,000 16,000 15,200 12,500 15,000 12,500 15,300 18,700 10,300 13,500 1L600 9,500 Per cent. 44 43 28 43 25 32 39 47 47 32 64 28 33 40 46 21 28 38 43 44 50 37 20 39 Per cent. 84 83 fl Reduced to 12 Per cent Moisture. 81 6 60 8 9 78 58 75 81 92 68 15 Red oak 84 86 70 24 I-Sll lernut liirknrv 60 Pecan hickory 72 ♦Actual tests on " dry " material not reduced for moisture. SUPPORTS OF THE RAIL 165 TABLE XXXVII. -RESULTS OF TESTS IN BENDING — AT RELATIVE ELASTIC LIMIT SUMMARY OF MECHANICAL TESTS ON THIRTY-TWO SPECIES OF AMERICAN WOODS (Division of Forestry, Circular 15) (Pounds per square inch] No. — Number of Tests. Highest Test. Test. ,1 llmlii'M 10 Per cent of Tests. Average of I.owcM 10 Per cent of Tests. Average of all Tests. Proportion of Tests within 10 Per cent of Average. Proportion of Tests 25 Per 'cent of Average. Modulus of Elas- ( Average of all Tests). Reduced to 15 Per cent Moisture. 1,160 390 330 650 130 95 170 87 218 216 49 256 57 117 31 153 257 187 75 25 72 37 18 44 87 10 118 13.500 12.900 11,900 12,700 10.000 11,300 13,700 12,000 13J00 15,700 11,600 10,600 14,200 14,500 12,000 11,800 11,800 13,100 13,500 16,100 15,400 11,900 14,300 12,200 15,000 17,500 9,700 10,700 11,500 13,200 11,000 2,400 2,200 2,900 3,100 4,100 3,100 3,000 2,200 4!400 4,000 5,100 5400 5,900 4,900 4,500 2,700 5,100 5,400 4,300 4,100 7,500 4,200 5,800 7,400 5,300 3!600 3,200 3,500 11,100 11,500 10300 8.200 10,300 11,200 7J390 9,600 14,100 9,500 ll|600 13,600 11,400 11,100 11,400 10,000 11,600 14,200 11300 14,000 11,200 14,400 16,400 io!ioo 10,400 13,200 10,100 5,400 5,600 4,800 5,400 4.500 4,500 5,000 4,200 4,000 3,400 6,100 6^000 5,000 5,600 7,800 5,100 5,500 4,300 6,600 7,700 7,800 4,800 7,600 6,400 7,900 8,300 5,400 5,800 5,200 3,200 5.100 8,500 7^200 8,200 6,400 7,700 8,400 6,600 9^00 81400 7,600 9,200 9,400 8,100 8,800 7,400 8,600 11,200 11,700 9,800 11,100 9,300 11,500 12,600 7,300 8,000 7,900 8,900 Per cent. 43 42 48 46 38 25 44 32 37 34 50 15 62 40 42 50 39 21 44 46 33 57 43 40 46 81 83 81 85 85 73 66 86 56 73 76 95 49 94 75 84 81 80 89 86 84 93 89 83 71 91 83 82 2,300,000 Reduced to 12 Per cent Moisture. 10 1 ).iuu!:i- spruce * 1,680,000 17 Yellow oak 1,740.000 19 Willrm oak 1,750,000 21 22 23 25 26 27 Shagliark hickory 2,390,000 2,320,000 2,080,000 2,280,000 1,940,000 2,530,000 2,730,000 Water hickory Bitternut hickory Xut nit-Li hickory Pecan hickory Pignut hickory 1,700,000 * Actual tests on "dry" material not reduced for moisture. TABLE XXXVII.— Concluded — RESULTS OF TESTS IN COMPRESSION, ACROSS GRAIN,* AND SHEARING WITH GRAIN SUMMARY OF MECHANICAL TESTS ON THIRTY-TWO SPECIES OF AMERICAN WOODS (Division of Forestry, Circular 15) [Pounds per square inch] No. Species. of Tests. Compres- G°rain S . Shearing with Grain not Re- duced for Moisture. No. Species. Number of Tests. Compres- Grab. Shearing with Grain not Re- duced for Moisture. 1 Reduced to 15 Per cent Moisture. 1,210 400 330 690 130 100 175 650 87 41 218 216 256 1,000 1,000 900 1,000 700 1,000 1,200 800 700 800 2,200 1,900 3,000 1,900 700 700 700 700 400 500 800 500 400 1,000 1,000 1,100 900 15 16 17 20 22 23 24 25 26 27 2* 29 30 31 Reduced to 12 Per cent Moisture. — Concluded. Red oak Southern red oak 57 117 30 153 255 135 14 25 72 37 18 87 10 118 2,300 2,000 2|000 1,600 1,800 2,700 3,100 2,400 2,200 2,700 2,800 3,200 1,200 2,100 1,900 1,700 1,400 1,100 1,100 Reduced to 12 Per cent Moisture. Willow oak Spanish oak Shagbat 1; hickory 900 900 1,100 Water h.ckorv Bitternut hickory Nutmeg hickory Pignut hickory White elm * To an indentation of 3 it of the height of the in "dry" material not reduced for 166 STEEL RAILS TABLE XXXVIII. — STRENGTH VALUES FOR STRUCTURAL TIMBERS (Forest Service, Circular 189) BENDING TESTS ON GREEN MATERIAL Sizes. H 1 j3 F. S. a E. L. M. of R. M. of E. Calculated Shear. g a u4 j ^ Species. 1 % s o II II ej 1 1 | 2 1 g, II |£ 1 -<' 2JJ M 5„. 5,. Ins. Ins. Lbs. Lbs. 1000 Lbs. Lbs. Longleaf pine 12X12 138 4 2S 6 9." 4099 83 6710 0.74 .71 1523 0.9! 261 306 0.86 10X16 168 4 26. S 16.' 4193 .85 6453 1626 1.05 1.01 8X16 156 7 28.4 14. ( 3147 .64 5439 .60 1368 390 1.29 6X16 132 1 10.8 21 ..- 4120 .83 6460 .71 1190 " 378 1.25 6X10 180 1 31.0 6.S 3580 .72 6500 .72 1412 .92 175 .58 6X 8 180 2 '27.0 8.5 3735 .75 5745 .63 1282 .83 121 .40 2X 2 30 15 33.0 14. 4950 1.00 9070 1.00 1540 1.0C 303 1.00 Douglas fir 8X16 180 191 31.5 11. ( 3968 76 5983 .72 1517 95 269 172 81 5X 8 180 84 30.1 10. * 3693 .71 5178 1533 .96 .52 2X12 180 27 35.7 20.( 3721 .71 5276 .64 1642 1.03 256 .77 2X10 180 26 32.9 21. ( 3160 .60 4699 .57 1593 1.00 189 .57 2X 8 180 29 33.0 17. ( 3593 .69 5352 .65 1607 1 01 171 .51 2X 2 24 508 30.4 11. ( 5227 1.00 8280 1.01 1597 L.0( 333 1.00 Douglas fir (fire-killed) . . 8x16 180 30 36. N 10.' 3503 .80 4994 .64 1531 .94 330 1.19 2x12 180 32 34.2 17.' 3489 .80 5085 .66 1624 .99 247 .89 2x10 180 32 38.9 18. 3851 .88 5359 .6! 1716 1.05 216 .78 2x 8 180 31 87.0 15." 3403 .78 5305 .68 1676 1.01 169 .61 2X 2 30 200 38.2 17.1 4360 1.00 7752 1.00 1636 1.00 277 1.00 Shortleaf pine 8X16 180 12 80.5 12. 3185 .73 5407 .70 1438 1.03 362 1.40 8X14 180 12 45.8 12." 3234 .74 5781 .75 1494 1.07 338 1.31 8X12 180 24 52 . 2 11. E 3265 .75 5503 .71 1480 1.06 277 1.07 5X 8 180 24 I7.s 11. 1 3519 .81 5732 .74 1485 1.06 185 .72 2X 2 30 25 1: 51.7 18. ( 4350 1.00 7710 1.00 1395 1.00 258 1.00 Western larch 8X16 180 82 51.0 25.: 3276 .77 4632 .64 1272 .97 298 1.11 8X12 180 30 50 . 3 23 . '. 3376 .79 5286 .73 1331 1.02 254 .94 5X 8 180 14 5(3.0 25 ( 3528 .83 5331 .74 1432 1 09 169 .63 2X 2 28 189 1(3.2 2(3 1 4274 1.00 7251 1.00 1310 i 00 269 1.00 Loblolly pine 8X16 180 17 45.8 6.1 3094 .75 5394 .69 1406 .98 383 1.44 5X12 180 94 00,9 5.S 3030 .74 5028 .64 1383 .96 221 .83 2X 2 30 44 70.9 5.4 4100 1.00 7870 1.00 1440 1.00 265 1.00 Tamarack 6X12 162 15 57.6 16.6 2914 .75 4500 .66 1202 1.05 255 1.11 4X10 162 15 43 . 5 11.4 2712 .70 4611 .68 1238 1.08 209 .91 2X 2 30 82 38.8 14.0 3875 1.00 6820 1.00 1141 1.00 229 1.00 Western hemlock 8X16 180 39 42 . 5 15.6 3516 .80 5296 .73 1445 1.01 261 .92 2X 2 28 52 51.8 12 J 4406 1.00 7294 1.00 1428 1.00 284 1.00 Redwood 8X16 180 14 X0.5 19. ! 3734 .79 4492 .64 1016 .96 300 1.21 6X12 180 14 S7 . 3 17. .s 3787 .80 4451 .64 1068 1.00 224 .90 7X 9 180 14 79.8 10.7 4412 .93 5279 .76 1324 1.25 199 .80 3X14 180 13 86.1 23.7 3506 .74 4364 .62 947 .89 255 1.03 2x12 180 12 70 9 18.6 3100 .65 3753 .54 1052 .99 187 .75 2x10 180 13 55.8 20 3285 .69 4079 .58 1107 1.04 169 .68 2x 8 180 13 S3 . 8 21.5 2989 .63 4063 .58 1141 1 .OS .134 .54 2X 2 28 157 75.5 19.1 4750 1.00 6980 1.00 1061 1.00 248 1.00 Norway pine 6X12 162 15 50.3 12 5 2305 .82 3572 .69 987 1.08 201 1.17 4X12 162 18 47.9 14.7 2648 .94 4107 .79 1255 1.31 238 1.38 4X10 162 16 45 . 7 13.3 2674 .95 4205 .81 1306 1.30 198 1.15 2X 2 30 133 32 8 11.4 2808 1.00 5173 1.00 960 I 00 172 1.00 Red spruce 2X10 144 14 32.5 21.9 2394 .66 3566 .60 1180 1.02 181 .80 2x 2 26 60 37 8 21 3 3627 1.00 5900 1.00 1157 1 00 227 1.00 White spruce 2x10 144 16 40.7 9.3 2239 .72 3288 .63 1081 1.08 166 .83 2X 2 26 83 58.3 2 3090 1.00 5185 1.00 998 1. 00 199 1.00 SUPPORTS OF THE RAIL 167 TABLE XXXVIII. — Continued COMPRESSION AND SHEAR TESTS ON GREEN MATERIAL Compression || to grain. Compression J_ to grain. Shear. Species. § s 1 1 H 1 a 1 1 1 H-g 6 M 21 2& i < 1 X a H | 1 1 ?5 h4 1 | 1 1 § (2 l §1 4X4 2X2 6X6 5X6 2X2 6X6 2x2 6X6 5X8 2X2 46 14 515 170 902 108 201 95 23 2S1 26.3 34 7 30 . 7 30.9 29.. s 34.8 37.9 -11.2 4:: . 5 51.4 Lbs. 3480 1000 Lbs. Lbs. 4800 4400 3500 3490 4030 3290 3430 3436 3423 3570 Ins. 4X4 Ins. 4 22 25.3 Lbs. 568 44 21.8 Lbs. 973 2780 2720 3500 2620 1181 2123 1925 1801 4X8 16 259 30.3 570 531 29.7 765 Douglas fir (fire-killed) . . 6X8 16 24 33.7 368 77 35.8 631 2514 2241 1565 1529 5X8 5X8 5X8 5X5 2X2 6X8 6X8 4X6 4X4 8X4 4X4 16 14 12 8 2 16 12 6 4 8 8 12 12 24 24 277 22 20 53 30 16 38 37.7 42 . 8 53.0 47.0 4S.5 43.0 40.2 52. s 50.4 07 . 2 44.6 361 366 325 344 400 417 416 478 472 392 546 179 47.0 704 6X6 2X2 107 491 49.1 50.6 2675 3026 1575 1545 3510 3696 179 40.7 700 Loblolly pine 8X8 4X8 2X2 6X7 4X7 2X2 6X6 2X2 6X6 2X2 14 18 53 4 6 165 82 131 34 143 65 4 60.0 74.0 49.9 27.7 3(3.8 46 . 6 55.6 83 6 72.1 1560 2430 365 691 2140 3560 3240 3032 3360 3190 3355 3392 3882 3980 121 83.2 630 2332 2444 1432 1334 24 39 . 2 668 Western hemlock 2905 2938 3194 3490 1617 1737 1240 1222 6X4 6 30 48.7 434 54 65.7 630 6X8 6X6 6X7 6X3 6X2 6X2 6X2 2X2 16 12 9 14 12 10 8 2 13 14 13 13 12 11 12 1S6 8G.7 53.0 71.7 75 6 .6 5 V, 56.7 75.5 473 424 477 411 430 423 396 569 148 84.2 742 6X7 4x7 2X2 2x2 2X2 5 8 178 58 84 29 28 4 20 8 35 4 61.0 1928 2154 905 1063 2404 2652 2504 2750 2370 20 26.7 589 2X2 2X2 2 2 43 46 31. S 50.4 310 270 30 40 32.0 3S.0 758 651 168 STEEL RAILS TABLE XXXIX. — UNIT STRESSES FOR STRUCTURAL TIMBER RECOMMENDED BY THE COMMITTEE ON WOODEN BRIDGES AND TRESTLES AM. RY. ENG. ASSN. [Pounds per Square Inch] Bending. Shearing. Compression. o^ Kind of Timber. Extreme Fiber Stress. Modulus of Elas- ticity. Parallel to Grain. Longitudi- nal Shear in Beams. Perpendic- Grain. Parallel to Grain. For Columns 15 Diams. Safe Formulas for Safe Stress Columns over .15 Diams. If 2 II "§! 1 II !| E'i "I la k5 fl as u l! Douglas fir .... 6100 1200 1,510,000 690 170 270 110 630 310 3600 1200 900 ""O-efe) 10 Longleaf pine. . . 6500 1300 1,610,000 720 180 300 120 520 260 3800 1300 980 M'-Wd) 10 Shortleaf pine... 5600 1100 1,480,000 710 170 330 130 340 170 3400 1100 830 M'-^d) 10 White pine 4400 900 1,130,000 400 100 180 70 290 150 3000 1000 750 ™( l -m) 10 S ruce 1100 830 1100(1 L ) Norway pine. . . 4200 800 1,190,000 590 130 250 100 150 2600* 800 600 V 60 D ) Tamarack 4600 900 1,220,000 670 170 260 100 220 3200* 1000 750 M'-do) Western hem- 5800 1100 1,480,000 630 160 270* 100 440 220 3500 1200 900 1200 (l-^ 900 (l L ) Bald cypress. . . White oak 5700 1100 1,150,000 840 210 270 110 920 3500 1300 980 M'-m) 12 Note. — T ese un it stre ses are for a gree n cond tion o D = \ >e usee withe th in inch ig the live-load s tressea The difference between green and seasoned wood may amount to as much as 50 per cent as shown by Table XL. The influence of seasoning consists in (1) bringing by means of shrinkage about 10 per cent more fibers into the same square inch of cross section than are contained in the wet wood; (2) shrinking the cell-wall itself by about 50 per cent of its cross section and thus hardening it, just as a cowskin becomes thinner and hardens by drying. Table XL applies only to small, clear pieces of wood seasoned under special conditions with great care. The Forest Service has found * that a comparison of the results of tests on seasoned material with those from tests on green material shows that, without exception, the strength of 2 by 2 inch specimens is increased by lowering the moisture content, but that increase in strength of other sizes is * Strength Values for Structural Timbers. McGarvey Cline. Forest Service, Circular 189, Jan. 25, 1912. SUPPORTS OF THE RAIL 169 much more erratic. Some specimens, in fact, show an apparent loss in strength due to seasoning. In the light of these facts it is not safe to base working stresses on results secured from any but green material. TABLE XL. — REDUCTION FACTORS FOR STRESS AT ELASTIC LIMIT IN BEND- ING OF LONGLEAF PINE (Forest Service, Bulletin 70) From — To — Moisture 2 *■ 6. 8. 10. 12. 14. 16. 18. 20. 22. 24. 26.* 2 1 1.13 1.31 1.53 1.75 1.99 2.20 2.39 2.54 2.70 2.85 2.99 3.14 4 .882 1 1.15 1.35 1.54 1.75 1.94 2.11 2.25 2.39 2.52 2.64 2.77 6 .767 .867 1 1.17 1.34 1.52 1.69 1.83 1.95 2.07 2.18 2.29 2.41 8 .656 .742 .856 1 1.15 1.30 1.44 1.57 1.67 1.77 1.87 1.96 2.06 10 .572 .648 .746 .882 1 1.13 1.26 1.37 1.45 1.54 1.63 1.71 1.80 12 .503 .570 .657 .768 .881 1 1.11 1.20 1.28 1.36 1.44 1.51 1.58 14 .455 .515 .594 .694 .795 .904 1 1.09 1.16 1.23 1.30 1.36 1.43 16 .419 .475 .547 .639 .733 .832 .921 1 1.07 1.13 1.19 1.25 1.32 18 .393 .445 .513 .600 .688 .781 .865 .938 1 1.06 1.12 1.17 1.24 20 .370 .420 .485 .565 .648 .735 .814 .884 .941 1 1.05 1.11 1.16 22 .351 .397 .458 .535 .614 .697 .771 .838 .593 .948 1 1.05 1.10 24 .335 .379 .437 .510 .585 .665 .735 .799 .851 .904 .954 1 1.05 *26 .318 .361 .415 .486 .556 .633 .700 .760 .810 .860 .908 .951 1 A recent instructive series of tests* have been conducted by W. K. Hatt in the Laboratory for Testing Materials of Purdue University, in cooperation with the Wood Preservation Committee of the American Railway Engineering Association and with the following organizations: Big Four Railroad Company. Illinois Central Railroad Company. American Creosoting Company. Ayer and Lord Tie Company. Atchison, Topeka and Santa Fe Railway Company. Forest Service, U. S. Department of Agriculture. The principal results of these tests are shown in Table XLI. One of the main determinations of the tests was of the resistance of the ties to the direct pressure of the rail. It was shown that the various treatments had not weakened the ties, except in the case of ties newly treated with crude oil. The tie was put through a planer, so that one surface was true. The other surface was adzed at the place of bearing to provide a true bearing for the plate representing the bottom of the rail or the tie plate. * Fourth Progress Report of Tests on Treated Ties, Proceedings Am. Ry. Eng. & M. of W. Assn., 1910, Vol. 11, Part 2. 170 STEEL RAILS TABLE XLI. — BEARING STRENGTH OF TIES UNDER THE RAIL (See Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 11, Part 2, pp. 853-4) Red oak Loblolly pine Shortleaf pine Longleaf pine Red gum Total 1. Crude oil, 529. 1. Crude oil, 373. 1. Crude oil, 655. Tests were made upon 581 half -ties to determine the relation of the crush- ing strength of the ties with and without the tie plates. The fiber stress per unit of area of wood under the tie plate at the elastic limit in the case of the oak are less than those under the rail alone except for plate C (see Fig. 124). Of course, the total load is greater. This is accounted for by the perceptible springing of the tie plates, thus producing a non-uniform pres- Ep3T* □ D y ■ 7 /e n r;: 1^6 tl 7" 1 . L i ^> U ft K K TJ m ^F Fig. 124. — Tie Plate Forms used in „ Tests at Purdue University. Fiber Stress in Tie Plates at Elastic ?<* Limit: A 37,500 lbs. persq. in.; B68,800 lbs. per sq. in.; C 59,800 lbs. per sq. in. SUPPORTS OF THE RAIL 171 sure on the wood under the tie plate. The loads, therefore, carried with the aid of a tie plate, while larger, are not increased in the same ratio as the increase of bearing surface. In the loblolly-pine ties and in plate C on red oak, no perceptible spring- ing of the tie plate was observed within the elastic limit of the timber, the load being increased in practically the same ratio as the surface. Tie plate A (see Fig. 124), i 7 e inch thick, was permanently bent at the edge of the rail bearing when the test was carried to j-inch compression on oak ties. The yielding was confined almost entirely to the edge of the rail bearing. Tie plate B, | inch thick at edge of the rail, was not permanently bent by the same test. It, however, springs as much, or more, than plate A, but the springing was more uniform. Plate B is harder metal, and this would seem to be an advantage in this test. The three tie plates were tested under flexure to determine the quality of the metal. The results are shown in Fig. 124. In the calculations of the strength of the tie, if we take the strength of the wood as shown by Table XLII, the result will be not far from correct. The working stress at the rail bearing given in the table refers to the allowable stress under the tie plate. TABLE XLII WORKING STRESSES FOR TIE TIMBER Kind of Wood. Working Stress (Pounds per Square Inch). Compression at Rail Bearing. Extreme Fiber Stress in Cross Bending. Oak. . 500 325 200-250 1000 1200 750 Longleaf pine Examining the safe load the tie in the track will carry, we have to con- sider two sources of possible failure of the tie: 1. The compression of the fibers under the tie plate. 2. The rupture of the tie due to too great a bending moment in the tie. A 6 by 9-inch tie plate gives an area of 54 square inches. Referring to Table XLII, we find the permissible load on the tie plate to be 27,000 pounds for oak ties, 17,500 pounds for longleaf yellow pine, and about 11,000 to 13,000 pounds for the inferior woods. Let us now consider the bending moment in the tie. 172 STEEL RAILS If the tie were completely rigid, there would result a uniform distribution of the pressure on the ballast. This is, however, never realized, and there is an unequal distribution of the pressure. The tie should be considered as a continuous beam, supporting a vertical load at two points and resting on material which is, within certain limits, com- pressible. Exactly what takes place in the ballast under the loaded tie is of the greatest importance in determining the bending of the tie. * M. Coiiard found that the vertical displacements of cross-ties hardly reach three millimeters (f inch), and that they are not proportional to the weights supported. He has concluded from his experiments that "the cross- ties fixed to the rail remain, at certain points, suspended above the ballast, and that right at the rail there is formed under even the best tamped cross- ties some depressions of ballast on the edges of which the cross-tie is supported; that under the passage of a wheel even lightly loaded the cross-ties come in contact with the ballast and deflect to the depth of the depressions." Shwedler, Hoffman, Schwald, Riese, and Zimmerman, from the theoretical researches of Winckler, have derived the elastic curve of the tie represented Fig. 125. — Elastic Curve of Tie, 7 feet 10.4 Fig. 126. — Elastic Curve of Tie, 8 feet 10.3 inches long. (After Winckler.) inches long. (After Winckler.) by Fig. 125 or Fig. 126, according as the cross-tie was 2 m. 40 (7 feet 10.4 inches) or 2 m. 70 (8 feet 10.3 inches) long. Very careful experiments have been made by M. Cuenot on the relative action of the tie and the ballast. f The following record of his tests is taken from Mr. W. C. Cushing's translation of his work: "The rails employed were of the type used on the Paris, Lyons and Medi- terranean, either the P. M. type, of a weight of 39 kilograms per running meter (78.6 pounds per yard), or the P. L. M.-A. type, of a weight of 34J kilograms per running meter (69.5 pounds per yard). "All my experiments, during nearly three years, have been made, first, on a side track, then on track No. 2 of the line from Mouchard to Bourg, trav- ersed by the express and fast trains, comparatively with oak cross-ties employed on the P. L. M. system, and with composite cross-ties (wood and steel). (See Fig. 127.) Finally, a special track for experiments was laid at the Bourg * Revue des Chemins de Fer, July, 1897. f Deformations of Railroad Tracks and the Means of Remedying Them. G. Cuenot, 1907, New York. SUPPORTS OF THE RAIL 173 station, and there was tested, at the same time as the two types of cross-ties mentioned, the metallic cross-tie in use on the State System. "The wooden cross-ties were oak, creosoted, and of the following dimen- sions: Length 2 m. 60 (8 ft, 6.36 in.) Width m. 22 to m. 25 (8.66 in. to 9.84 in.) Depth m. 14 to m. 15 (5.51 in. to 5.91 in.) "The composite cross-tie was composed of a metallic skeleton in the form of an inverted trough, provided in the interior with two symmetrical blocks of wood solidly fixed, and leaving between them an empty central space." ; - - -»»'--- 4 fcno^-JPL_ 15.75: ._l5.75"--»U-_ 15.75". PART TAMPED WITH TAMPING BAR PART TAMPED V SPONTANEOUS Fig. 130. — Results of M. Cuenot's Tests on Ties. The following conclusions have been drawn by M. Cuenot from his ex- periments : " (a) The long ties, 8 feet 6.36 inches to 7 feet 6.6 inches, take, under the load, the form of a basin with the bottom slightly raised in the center. " (6) The short ties, 7 feet 0.6 inch to 6.5 feet, are deformed according to a curve, convex or otherwise, and inclined toward the extremity. SUPPORTS OF THE RAIL 177 " (c) The ties between 7 feet 0.6 inch and 7 feet 2.64 inches are lowered parallel with themselves without sensible curvature. "(d) The unsymmetrical tamping raised the curve towards the center; a very feeble lack of symmetry reacts very clearly in this direction. "(e) It is possible, by increasing the rigidity of a cross-tie, notably by concentrating the material about the supports, to reduce its sinking to the quantity which is intended as a limit, and its flexure in such measure as one would wish. "(f) The permanent sinking of the ballast is variable according to the case, but the elastic sinking, the only one there is reason to consider, is, so to speak, constant, whatever be the length and type of the cross-tie adopted. The deformation is slowly produced and augments with time." It is here seen that a tie 8 feet 6 inches long, which is the usual length of tie employed in this country, under proper conditions of tamping, will assume Fig. 131. — Strain Diagram of Entire Tie. the loaded position shown in Fig. 131. In the figure, the loads IF at A and C represent the load at each rail. Considerations of the tamping under the tie will not admit of any exact mathematical formula for the distribution of the pressure of the ballast. If, however, as a working hypothesis, we assume that the pressure of the ballast is uniformly distributed between the rails and that the pressure is similarly uniformly' distributed, but of greater intensity from the rail to the end of the tie, and, further, that the tangent to the elastic curve of the loaded tie is hori- zontal under the points of support of the rail, then approximate formulae can be readily derived for the maximum bending moment in the tie and the greatest intensity of pressure of the ballast in terms of the load on the tie at either rail bearing. This assumption, while not taking into account all the conditions of the loading of the ballast nor giving the exact distribution of pressure under the tie, will, nevertheless, when applied to an 8-foot 6-inch wood tie, afford a means of determining the maximum bending moment and the greatest intensity of pressure with sufficient accuracy for our purpose, and very possibly as exactly as the present state of our knowledge of the subject warrants. 178 STEEL RAILS Where it is desired to investigate the action of ties in a more thorough manner, the calculations may be proceeded with in the same manner as those for the case where the rail acts as a continuous girder in Article 23. It should be borne in mind, however, that the coefficient of the ballast or the ratio of pressure to sinking is not the same for all parts of the tie, but with proper conditions of tamping is considerably greater under the tie in the region adjacent to the rail bearing. Referring to Fig. 132, the moments at the supports A and C are equal and each ^ W'L', where W is the total load uniformly distributed over ■j— - .iiw' Fin. 132. — Strain Diagram of Tie between Rails. the span U. The bending moment at the center of the span B is ii W'L'. Therefore, the maximum bending moment occurs at the supports and is M m = -h W'L'. The free part of the tie outside the rail acts as a cantilever; the maximum bending moment occurs at C and is M c = ^ W'L" , where W" is the total load uniformly distributed over the span L" (Fig. 133). Fig. 133. — Strain Diagram of Tie outside of Rails. Considering the tie as a whole, Fig. 131, we have, from the principle of the continuous girder, M c = j% W'L' = \ W"L", but for an effective length of the tie of 100 inches, L' = 60 inches and L" = 20 inches; therefore iV W 60 = \ W" 20 W' =2 W". But the reaction at any support is equal to the algebraic sum of the shear to the right and left of the support, and W = J cl + J CT W = \W' + W" w = I W' + \ W' W = W' = 2 W", where W = the load at either rail bearing, J cl = the shear immediately to the left of C, J„ = the shear immediately to the right of C. SUPPORTS OF THE RAIL 179 Substituting the value of W in the equation for the maximum bending moment, M m = M a = M e , M m = iV W X 60, M m = 5 W, where M m = maximum bending moment, M a = bending moment at A, M c = " " " C. The extreme fiber stress, / = —f- = — —- , or W = ^— • J I I 5y For a rectangular tie, and W = y 12 " 2 " 30 " Turning to Table XLII, we find the allowable extreme fiber stress in bend- ing 1000 pounds per square inch for oak, and 750 pounds per square inch for the inferior woods. We can, therefore, prepare Table XLIII, showing the safe load that the tie can bear and not exceed a proper bending stress. TABLE XLIII. — ALLOWABLE LOAD ON TIE AS DETERMINED FROM EXTREME FIBER STRESS IN BENDING Kinds of Wood Size of Tie. Allowable Load Applied at Each Rail Bearing. Oak Oak . Inches. 7X8 7X9 *Half round 7X8 7X9 *Half round Pounds. 13,100 14,700 15,000 9,800 11,000 11,300 Oak 17. Bearing on the Ballast Considering now the bearing power of the ballast on which the tie rests, the maximum loading on the ballast under the tie per linear inch of the tie, from the preceding article, is 180 STEEL RAILS To express W in terms of the bearing power per square foot of the ballast (p), and the width in inches of the base (6), we have the allowable load per linear inch of the tie equal to bp _ W 144 2 x 20' For bearing on gravel or broken stone, not well confined, three tons per square foot is as much as should be allowed. We may now prepare Table XLIV, showing the safe load that can be applied at each rail bearing as determined by the proper load on the ballast. TABLE XLIV. — ALLOWABLE LOAD ON THE TIE AS DETERMINED BY THE SAFE LOADING OF THE BALLAST Width of Base of Tie. Allowable Pressure \pplieil at Each Rail Bearing of the Tie. Inches. 8 9 *12 Pounds. 13,500 15,000 20,000 18. Bearing on the Subgrade Before assuming a proper bearing under the tie, an examination must be made of the distribution of the load to the subgrade. The following experi- ments have been made in Germany to determine the distribution of force upon the subgrade.* An experimental box, 37 inches long, 20 inches high, and 6 inches wide, was filled with a layer of clay 8 inches high at the bottom, on top of which was placed a layer of sand 6 inches high, and then a layer of gravel 6 inches high, upon which a tie was laid. This tie was tamped with the ordinary tamping pick and then subjected to a load of 57 pounds per square inch, or 8200 pounds per square foot, by which the rail level was depressed. By the use of an eccentric the loading was alternately lifted from the tie and again returned, thus imitating the process of passing a loaded wheel over the track. As soon as the tie had settled 1.2 inches, which was registered upon an attached sliding plate, the tie was again raised and tamped. From time to time photog aphic views and observations as to the stage or condition of the experiment were taken * Glaser's Annalen fur Gewerbe und Bauwesen. May, 1899. (Director Schubert.) Transla- tion appears in Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 7, p. 105. SUPPORTS OF THE RAIL 181 by removing the front wall of the experimental box. After the eleventh tamp- ing the experiment was considered as completed, and the section shown in Fig. 134 was taken. From this view we can easily see how a short depression, measuring about 12 inches to 14 inches wide, has been formed in the clay, with an upward swelling Fig. 134. — Ballast Experiments — Schubert. Six inches of sand and 6 inches of gravel. on each side. The pressure transmitted from the tie has accordingly distributed itself over this small width when the depth below the bottom of the tie was 12 inches. In a subsequent experiment, broken stone was used in place of gravel; otherwise the procedure was the same. From a photograph of the section after the fifth tamping (see Fig. 135) a depression in the clay extending nearly Fig. 135. — Ballast Experiments — Schubert. Six inches of sand and 6 inches of stone. over the entire width of the experimental box (27| inches to 29| inches wide) is noticeable. The distribution of the force is consequently double that of the previous experiment. Still more favorable appears this distribution when the height of the stone ballast is increased. In doing this, it is judicious to retain a thin layer of sand so as to prevent the larger pieces of broken stone from entering into the clay. 182 STEEL RAILS As will appear from the section shown in Fig. 136, a depression in the clay has not taken place, and only a few of the broken stones have gone through the sand to the clay. In emptying the box only a very unimportant depression was noticeable. - Ballast Experir - Schubert. Stone with thin layer of sand. Finally, the behavior of a foundation layer was investigated, and after the fourth tamping the section shown in Fig. 137 was taken. The stones of the foundation layer have penetrated the clay rather deep, and not only those in the center, but also stones on the sides, from which we can conclude that Fig. 137. — Ballast Experiments — Schubert. Stone resting on clay subgrade. the force transmitted through the tie has distributed itself nearly over the entire width of the box. Hence, the most favorable distribution of forces is accomplished by the use of ballast of broken stone, with or without a foundation layer. The latter is, however, not suitable in a yielding subgrade, inasmuch as the stones pene- trate into the grade, and the yielding soil will swell into the spaces, thus making the drainage ineffective. The effect of overloading the subgrade is very clearly shown in Fig. 138. SUPPORTS OF THE RAIL 183 * The road department of the Pennsylvania Railroad has installed an interesting piece of apparatus on the grounds of the South Altoona foundry to test the bearing qualities of different kinds of roadway and ballast. The Fig. 138. — Effect of Overloading the Subgrade. (Am. Ry. Eng. Assn.) particular ballast or subgrade to be tested is placed in three heavy boxes that extend across the track and have sufficient depth to serve the purpose. The track crosses this on a level and extends out on either side, terminating in a short Fig. 139. — Pennsylvania Track Testing Apparatus. (Railway Age Gazette.) and sharp incline. A four-wheel car on this track is loaded with pig metal to obtain any desired weight on the wheels. This car is also equipped with electric motors. A shed built across the track carries an overhead rail, from which a motor current is obtained, and a contact shoe is on the car. Fig. 139 illus- trates the apparatus. * Railway Age Gazette, June 11, 1909, and July 21, 1911. 184 STEEL RAILS When current is turned on, the car moves out to the end of the conductor rail, and here, as the contact is broken, the power of the motor is shut off. The car runs on until stopped by the adverse grade, and meanwhile a trip reverses the current connections to the motor. Stopped by the grade, the car runs back, beneath the current rail, when its motor drives it to the other end, where the movement is again reversed. In this way the car is made to travel back and forth automatically over the track until the desired results are obtained, the number of trips being automatically registered upon a counter. These tests are the most extensive of the kind ever conducted in this country. It was felt that while the data obtained by Mr. Schubert were very instructive yet more valuable data could be obtained from a series of experi- ments if made in a manner more nearly approaching actual track conditions.* The track was 109 feet in length, built of new P. R. R. standard 85-pound rail with 7-inch by 9-inch by 8§-foot ties spaced 25£ inches center to center. It being impracticable to run the car faster than about five miles per hour, at which speed any effect upon the track, due to impact alone, would be negligible, a weight of 75,000 pounds per axle was chosen for the experimental truck. A series of five tests has been completed; the first one beginning on Sept. 2, 1908, and the last one ending on Aug. 2, 1910. Table XLV gives general data of the tests. Water was applied by sprinkling the boxes to observe the effect of moisture on the ballast; the amount applied in each test is shown in the table by inches of rainfall. In test No. 1 the line of demarkation between the bottom of the ballast and the roadbed material was not straight. The test showed conclusively that a depth of 8 inches of trap-rock ballast, when laid on the usual roadbed ma- terial, was not sufficient to distribute the weight carried by the ties uniformly over the roadbed. The results in the third box showed, however, that if 12 inches of per- meable material, such as cinder, were used beneath the 8 inches of ballast, the distribution of the weight over the roadbed material was much better. The results of the first test led to the second test to determine how a depth of 12 inches, 18 inches, and 24 inches of trap rock under the ties would behave. In test No. 2 the dividing line between the ballast and the loam was quite straight in box No. 3, but in boxes Nos. 1 and 2 there existed some depressions in the line especially under the rail. * Experiments to Determine the Necessary Depth of Stone Ballast. Report of the General Manager's Committee Pennsylvania Railroad. Proceedings Am. Ry. Eng. Assn., 1912, Vol. 13. SUPPORTS OF THE RAIL 185 A study of the sections in test No. 3 showed that the loam was more evenly depressed in box No. 3 than in the other boxes where stone had been substi- tuted for part of the cinder during the test. Test No. 4 showed that the gravel and slag distributed the pressure upon the loam with about the same efficiency. Test No. 5 was made to determine whether a combination of rock and cinder would prove as satisfactory as the rock alone. It was found, however, that the line between the ballast and the loam in box No. 3 was not as good as in box No. 3 of Test No. 2. TABLE XLV. — SUMMARY OF ROADBED TESTS AT ALTOONA. Test No. j 2 3 * 5 1st Part. 2nd Part. 1st Part. 2nd Part. 1st Part. 2nd Part. Fr r Sept. 2, 1908 Jan. 5, 1909. Apr. 18, 1909 June 15, 1909. June 28, 1909 July 20,1909. July 21, 1909 Aug. 6, 1909. Oct. 19, 1909 Nov. 17, 1909. Nov. 17, 1909 Dec. 3, 1909. May 19. 1910 June 24,1910. June 24, 1910 Aug. 2, 1910. Material in Box No. 1 27" bad clay 12" trap rock 26" loam 24" cinder 12" loam Removed 8 " placed with trap rock 24" slag 12" sandy moved and 8" trap rock added 24" cinder 13" sandy 6" cinder re- moved and 6" trap rock added Box No. 2 8 " trap rock 27" sandy 18 " trap rock 19° loam 24" cinder 12" loam Removed 12" placed with ^"oaf^ 12" slag re- moved and 12" trap rock added 13" sandy 8" cinder re- moved and added 5 r ° C Box No. 3 12" cinder 15" bad clay 24 " trap rock 14" loam 24" cinder 12" loam Unchanged 24" sandy 12" sandy 12" gravel re- moved and rock added 13" sandy 10" cinder re- 10" trap rock added No. of round Settlement: Box No. 1 Box No. 2 Box No. 3 Rainfall ■ 81,600 loft" w 98*" 49,932 8|" 9|" 111" 45,500 % 8|" 40,100 2|" fv 7" 45,561 124" 134" 8|" 40,060 21" 6" 19,210 1" 2i" 93,094 14 2 " For computing the bearing on subgrade we are furnished a method * by Mr. Thomas H. Johnson, who has made a study of Director Schubert's report with a view to deriving a formula which would show the thickness of ballast necessary to produce an equal distribution of the axle loads on the surface of the roadbed underneath the ballast. Referring to Fig. 140, the following formulae are suggested by Mr. Johnson: For gravel, ab = x = b' + § d'. For stone, ab = x = b' + d'. The relatively small arcs will approximate to parabolas and may be con- sidered as such. * Proceedings Am. Ry. Eng. & M. of W. Assn., 1906, Vol. 7. 186 STEEL RAILS The intensity of pressures is proportional to the ordinates of the curve. Areas of parabolic segment = %xy\ hence, mean ordinate = f y, or mean pressure = § maximum pressure, or maximum pressure equal to f mean pressure. Pressure at b = 0; hence, to obtain an approximately uniform distribution over the surface of roadbed, the tie spacing S must be such that the curves overlap and have a common ordinate, y' = \y. This will occur when db = \cb; or eb = \ ab; or mo = f mn.* We should obviously aim to space the tie so that the area of distribution of adjacent ties will overlap and give approximately an equal distribution of the axle loads on the surface of the roadbed underneath the ballast. W -^-^- Fig. 140. — Distribution of Pressure to Subgrade. (Johnson.) With a tie spacing of 23 inches centre to centre of ties, by applying Mr. Johnson's formulae, we find that it will be necessary to use 45 inches of gravel ballast and 22 inches of stone ballast under the tie to obtain equal distribution on the subgrade. Tie spacing, S = 23 inches = f x. For gravel, S = ! (6' + \ d'), or S = | V + | d', \d' = S -lb', and d' = | (S - f b') = | (23 inches - f 8 inches) = 45^ inches. For stone, S =!(&' + d'), or S = | V + f d', and d' = §(S-f&') = | (23 inches - f 8 inches) = * Approximate; to be exact, db = 0.29 cb and mo = 0.71 mn. = 22-f inches. SUPPORTS OF THE RAIL 187 It will be seen that unless an excessive depth of ballast is used, a uniform distribution of pressure on the subgrade will not be obtained. However, if the maximum pressure on the subgrade does not exceed its allowable bearing power, the fact that it is not uniformly distributed will not necessarily prove detrimental. From the above, we see that the maximum pressure = | mean pressure; W but from article 17 the mean pressure is tt— > and the maximum pressure is, therefore, 3 W_ W 2 40 x 27 x Substituting the value of x for stone and gravel ballast, we have the maxi- mum pressures: Gravel ballast, ^W+W) ' (1) Stone ballast, ^jfyj-y (2) We may take the depth d' for gravel ballast as 18 inches and for stone as 12 inches. Equations (1) and (2) will, therefore, reduce to: Gravel ballast, ^L_, (3) Stone ballast, W * +W) - (4) Equations (3) and (4) are, then, the expressions for the maximum pressure on the subgrade per square inch, in terms of the load on the tie and the width of the base of the tie. For bearing on clay foundation, subject to frost and usually made ground, 1 to 1| tons per square foot is good practice. Therefore, putting equations (3) and (4) equal to the bearing power of the subgrade, we can obtain the value of W. Gravel ballast, ^ = on ™ m , 144 27 (&' + 9) c . , n i 3000 W Stone ballast, — , —-_ ■ From which Gravel ballast, W = 563 (&' + 9), Stone ballast, W = 563 (&' + 12), Note. — Professor Talbot is now engaged on tests at the University of Illinois having for their purpose the determination of the distribution of pressure in gravel. These tests are not complete, but the evidence produced so far appears to indicate that the pressure under the center of the tie as shown in Fig. 140 is less than that at the edges, due to a distinct arching effect of the material under the tie. A very great difference in the distributing power of the sand was noted under different conditions of dampness. These tests when finished will doubtless furnish information of value in reference to the distribution of the rail pressure to the subgrade. 188 STEEL RAILS where W is the safe load in pounds applied to the tie at the rail bearing and b' is the width of the tie at its base in inches. Table XLVI shows the value of W for the different ties under consideration. TABLE XLVI. — ALLOWABLE LOAD APPLIED TO TIE AT RAIL BEARING AS DETERMINED FROM BEARING ON SUBGRADE Ballast. Width of Tie Allowable Load Applied to Tie at Kind. Depth below Tie. Rail Bearing. Inches. Inches. Pounds. 8 Gravel 18 9,600 9 Gravel 18 10,100 12 Gravel 18 11,800 8 Stone 12 11,300 9 Stone 12 11,800 12 Stone 12 13,500 19. Supporting Power of the Tie Table XLVI I assembles the information given in the previous tables. TABLE XLVII. — BEARING POWER OF TIES IN THE TRACK ' X (6, 12) Inches S Feet 6 Inches. (Half Round.) Allowable load, in pounds, applied at bearing of rail on tie, as determined by: Bearing of tie plate, Oak Longleaf yellow pine Inferior woods Bending of tie, Oak Inferior woods Bearing on ballast Bearing on grade, 18-inch gravel ballast 12-inch stone ballast 27,000 17,500 j 11,000 I 13,000 13,500 9,600 27,000 17,500 11,000 13,000 27,000 17,500 11,000 13,000 15,000 11,300 11,800 13,500 It would apparently seem that the weakest part of the substructure of the track lies in the bearing on the subgrade. In some cases of a very weak sub- grade, as in the muskeg swamps of Canada, it has been found necessary to resort to unusual methods of track construction in order to maintain the track in proper condition. Mr. D. MacPherson reported at the January, 1912, meeting of the Canadian Society of Civil Engineers the use of 12-foot ties in a SUPPORTS OF THE RAIL 189 stretch of track over muskeg, the resulting cheapening in cost of maintenance apparently fully warranted the extra expense of the large ties. If we consider the effect of the dynamic load, it will be noted from the discussion in the previous articles that the sinking of the tie in the ballast under the action of the dynamic load is little, if any, greater than under the static load, although the dynamic load is from 50 to 75 per cent greater in amount than the static load. As the calculations of the strength of the track must be made for the greatest load put upon it, which is the dynamic load, it would seem desirable to increase somewhat the safe bearing values given in the table as determined by the bend- ing of the tie and bearing on the ballast and subgrade. We are not warranted, however, in assuming a like increase in strength at the bearing of the tie plate under the action of the dynamic load, as the effect of the moving loads is, in this case, to reduce the strength of the wood. Examining Table XLVII as it applies to dynamic loading, it is seen that a bearing value of 14,000 pounds, or 7 tons, on half the tie can probably be taken with safety except in the case of the bearing of the plate on the soft-wood tie. The use of a soft wood, as cedar or loblolly pine, for ties under heavy traffic, with the customary form of plate and fastening in use in this country, is to be discouraged, and the general tendency at the present time is to use a wood better adapted to resist mechanical wear under these conditions. The rail in the track acts as a continuous girder, resting upon yielding supports. Evidently, therefore, not only must the allowable safe load on each tie be determined, but the yielding of the tie under the pressure of the rail must as well be considered. The relation of the bearing power of the tie to the amount it is depressed in the ballast is not thoroughly understood. The German engineers, Weber, Winckler, and Zimmerman, have advanced the theory that the pressure, P, of the ballast per unit of surface of the cross tie which it supports is, at each point, in direct ratio with the sinking, Y, of the latter; or P = CY when C is a coefficient depending upon the character of the ballast. The researches of these engineers may be summed up as follows : (a) The results of experiments are stated to agree quite closely with the supposition that the pressure on the unit of surface is in direct proportion with the measure of the sinking. * (6) With a subsoil supposed to be good, the magnitude of the coefficient of ballast has been found : for gravel ballast (without metalled bed) C = 3 ; for * P in kilograms per square centimeter; Y in centimeters. 190 STEEL RAILS gravel ballast (with metalled bed) C= 8; for ballast of small stones and scoriae C= 5. (c) The sinking observed under a load in motion, at speeds varying from 40 to 60 kilometers (24.85 to 37.28 miles) per hour, was not much greater than the sinking observed under the same load in a state of repose. Here again the fact that we are dealing with a dynamic load must be borne in mind, and at high speeds, when the dynamic augment of the wheel load is greatest, the bearing value of the tie corresponding to a given depression in the ballast is largely increased. The amount the tie is depressed in the track may be judged from the follow- ing evidence. Dr. P. H. Dudley gives from 0.2 inch to 0.4 inch as the amount the general running surface of the rail is below the trackman's surface. Director Schubert states that a wooden tie is depressed from 0.3 inch to 0.4 inch before it reaches a solid bearing. M. Couard observed that the maximum de- pression of the tie was about 0.12 inch, and states that the amount of depression is not proportional to the load. Fig. 130 shows M. Cuenot's tests in which a depression is left under the tie of about 0.04 inch and the loaded tie is depressed about 0.12 inch. * Fig. 141 illustrates an apparatus used by Bell for measuring and recording the deflection of the rails at various speeds. The following were the results obtained by the passage of a train in which the weights were: Tons. Cwt. Locomotive, running weight.. Tender Total weight of six carriages. 46 33 22 12 18 7f Speed of Train. Vertical Deflection. Miles per Hour. 4.2 14.9 26.7 40.4 57.1 65.2 0.25 0.25 0.27 0.25 0.33 0.30 The depression of the tie in the ballast is very erratic. Table LIX shows that in the tests made by the United States government on the depression of * The Development of the Manufacture and Use of Rails i Inst, of Civil Engrs., Vol. CXLII, April, 1900, p. 133. Great Britain, Bell. Proceedings SUPPORTS OF THE RAIL 191 rails the mean depression, under the drivers of an engine having axle loads of 44,000 pounds, was as follows: 60-pound rail 073-inch deflection 70-pound rail 138-inch deflection 85-pound rail 233-inch deflection All of these depressions were obtained in gravel ballast with static wheel loads and give results the reverse of what might have been expected. Fig. 141. — Bell's Apparatus for Measuring Depression of the Track. Fig. 142 shows the relation of the depression to the pressure on the tie. The dotted lines give Zimmerman's coefficients 3 and 8 and the dash line that suggested by Freeman's discussion in Article 21. These curves are straight LOAD PER LINEAR INCH UNDER ONE LI N E OF RAI LS (TIES SPACED 20IN) TONS (2000 LBS) \ --rv I '>-■>> - v ->,' u , a :--! 1 '*<;>' N IH v-N 1 x %± ' .^Zx - j^,s^ _ * ^ ■ - :: - r r v^ __~_.V_S ^e^: "vi'v " : : -^* .v!S " - - s \ ; __ -_ :*_:!. .. LOAD ON ONE HALF OF TIE TONS (2000 LBS) Fig. 142. — Reaction of Tie. lines plotted through the origin, this appears to be Freeman's assumption, but in the case of Zimmerman's analysis, owing to different parts of the tie depress- ing unequally, some variation should probably be made from a straight line. 192 STEEL RAILS It is quite evident that under the tie at the rail there is formed a depression of ballast, that even under a comparatively light pressure the tie deflects to the depth of this depression, and that from this moment only is the relation of the deflection to the. load of importance. From Mr. Love's analysis of the Government rail experiments (Article 23) we are furnished with a means of determining the relation between the pressure and deflection after the tie comes to a bearing in the ballast. The points plotted in Fig. 142 are obtained from Mr. Love's diagrams and represent the reaction of the tie referred to the depression measured from the highest point in the elastic curve of the rail between two drivers. The tie is assumed to come to a solid bearing at 0.20-inch depression below the trackman's surface. Bearing in mind that these points are obtained from a static load and that as far as the stresses in the rail are concerned the depth the tie depresses before it comes to a solid bearing is of comparatively small importance, we may construct the curve of pressures shown by the full line in Fig. 142. It is very probable that what really takes place is shown by the full line in the figure. The rail deflects under light pressures in some cases to as much as 0.20 inch and the tie comes in contact with a compact bed of ballast and the pressure from this point rises very rapidly in proportion to the deflection. In general it was found from the government tests that the ties in the center of the span between the drivers on light rail were supporting very light loads although in some cases they were considerably depressed in the ballast (see Plate XXIII) and for this reason it appeared that a better knowledge of the action of the ballast would be gained by referring the depression to the highest point in the rail between the wheels rather than to the trackman's surface. In the figure the pressure on the tie under the highest point of the rail between two drivers is plotted with a deflection of 0.20 inch below the trackman's surface and all the other deflections in the span referred to this. Above the limits of the experiments, the curve is flattened to provide for more rapid sinking caused by the increased pressure. CHAPTER IV STRESSES IN THE RAIL 20. Stress at Point of Contact of the Wheel with the Rail Passing from an examination of the external forces acting upon the rail to a consideration of the resulting stresses they produce in the material of the rail, let us first examine the stress at the point of contact between the wheel and the rail. The essence of the wheel is that its theoretical bearing surface shall be a mathematical line or point, affording no area of bearing surface whatever. In practice this is not strictly the case, owing to the elastic compressibility of the surface, but the bearing surface is always very small, nor can it be increased to advantage by making either the wheel or bearing surface more compressible. To such bearing surfaces the ordinary compression moduli of the textbooks have no application, as they are derived from experiments upon prisms which have the same bearing surface as the greatest section, or nearly so. Fig. 143. Condition of Free Flow. Fig. 144. Partially Restricted Flow. :ion Moduli. (After Johnson.) Fig. 145. Restricted Flow. * When a plain cylindrical column is subjected to a uniform compression stress over its entire cross section, as in Fig. 143, it may be said to be in a con- dition of "free flow," since it is free to spread in all directions throughout the length of the column. In Fig. 144 the material is compressed uniformly over a small area, as with a die. Here there is a flowing of the metal laterally, and * Paper contributed by Professor Johnson to the Engineers' Club of St. Louis, December, 1892. 193 194 STEEL RAILS then vertically, finding escape around the edges of the die. This is a condition of confined or restricted flow, and evidently the elastic limit here will be much higher than with the simple column. In Fig. 145 the surface is compressed by a cylinder, the greatest distortion being at the middle of the area of contact. When this metal is forced to move, or flow, it can find escape only out around the limits of the compressed area. But at these limits the metal is very little compressed, and, hence, must be moved from the center. The confined ring of metal inside the limits of external flow is now much wider, and, hence, the resistance to flow much greater, so that this condition will be found to have a higher elastic limit stress than that shown in Fig. 144, and very much above the ordinary " elastic limit in compression " which is found for the free-flow condition of Fig. 143. A careful set of experiments was made by Professors Crandall and Marston* to determine the elastic limits of steel rollers on steel plates. In these experi- ments eleven rollers were employed, from one inch to 16 inches in diameter, with pressures varying from 1000 to 14,000 pounds. Their results showed that the elastic limit load with soft steel rollers on steel plates per linear inch is P = 880 D, where P = load in pounds per linear inch of roller, D = diameter of roller in inches. Professor Johnson f experimented to determine the area of contact between locomotive and car wheels and rails. Sections of wheels were mounted in a 100,000-pound Riehle testing machine and short sections of rail were placed in the machine so that the wheel treads rested upon them in a normal position. They were then loaded with 5000-pound increments from 5000 to 60,000 pounds, the area of contact being measured after each loading. These actual areas of contact are given two thirds actual size in Fig. 146, and in Fig. 147 the areas are plotted with the area of contact as abscissa and the loads as ordinates. Professor Johnson states that no permanent distortion was noted upon either rails or wheels at the contact surface up to the 60,000-pound limit. It is seen from Fig. 147 that these areas plot practically upon a straight line through the origin, indicating that the area is directly proportional to the load. This being true, it must follow that the load divided by the area of contact, or the average stress per square inch over the area of contact, is a constant for all loads. This constant is something over 80,000 pounds per square inch. * Friction Rollers by C. L. Crandall and A. Marston. Trans. Am. Soc. of Civil Engrs., August, 1894, Vol. XXXII, pp. 99-129. t Discussion of Crandall and Marston's paper on Friction Rollers. Trans. Am. Soc. of Civil Engrs., September, 1894, Vol. XXXII, pp. 270-273. STRESSES IN THE RAIL 195 * Mr. Fowler, in his experiments on the relation of the load on the wheel to the area of the spot, found : Load on Wheel. Area of Spot. Pounds. Square Inch. 6,000 0.11 10,000 0.12 11,500 0.13 14,500 0.15 16,500 0.17 17,500 0.18 19,000 0.19 25,000 0.20 The following conclusions are drawn by Mr. Fowler from tests on the contact areas between wheels and rails: t That the average pressure on the metal in wheel and rail is within the safe limits at low loads, but at a load of 20,000 pounds the elastic limit is reached and permanent set begins in the rail; DIRECTION ALONG RAIL 2*3 r- fiioO 20000 30000 40000 fooOOOOOO 5000 lOOOO 20000 30000 40000 50000 lbs. Fig. 146. — Area of Contact between Wheel and Rail. (Johnson.) that the accumulated pressure at the center of the contact area is excessive with comparatively small loads, and is only prevented from doing injury by the support of the surrounding metal; that the effect of difference in diameter in wheels under the same load is insignificant and only appreciable when the difference is great; that a hard and unyielding cast-iron wheel damages the rail more than a steel wheel, and the wear of the rail will be greater with cast- iron than with steel wheels. * Proceedings Pittsburg Railway Club, November, 1907. t Bulletin of the International Railway Congress, London and Brussels, 1908, pp. 651-663. G. L. Fowler, Contact Areas between Wheels and Rails. See also G. L. Fowler, The Car Wheel 1907, p. 161. Giving the results of a series of investigations made for the Shoen Steel Wheel Co. 196 STEEL RAILS * Honigsberg describes a method proposed to be applied to measure the actual forces between the wheel and the rail. This is based on the fact that polished surfaces of iron or steel show peculiar markings — sometimes known as Luder's Lines — on the limit of elasticity being exceeded. As the limit of elasticity can be artificially raised to any value between the primitive elastic limit and the breaking strength, this gives a means of making standard test LOAD ON WHEEL IN POUNDS Fig. 147. — Relation between Areas of Contact and Load on Wheel. (After Johnson.) pieces; since when lines appear it may be concluded that the artificially raised limit has been exceeded. If a wheel passing over two calibrated pieces of metal causes the lines to appear on one and not on the other, it may be concluded that the actual stress caused by the wheel lies between the elastic limits of the two standard pieces. Tire wear would seem to indicate that the elastic limit of the metal was exceeded or too closely approached. The investigation of a committee of the Master Mechanics Association in 1895, on the wear of locomotive tires, has thrown interesting light on this subject. * Measurement of Forces between Rail and Wheel. des Eisenbahnwesens, Wiesbaden, 1904, pp. 109-160. O. Honigsberg, Organ fur die Fortschritte STRESSES IN THE RAIL 197 * Fig. 148 shows a diagram of the average wear of the tires of the fifty-three ten-wheel engines for which the calculations plotted in Fig. 7 were made, and Fig. 149 shows the same data of the eight-wheel engines shown in Fig. 6. The lower diagrams in Figs. 148 and 149 show the ratio of the rotative force to the weight on the rail, which we may call the " coefficient of slip." Since the coefficient of slip is the rotative force at the rail divided by the total weight of the drivers on the rail, it is evident that as this coefficient increases the tendency of the drivers to slip increases, and when it just equals the coeffi- cient of friction between the tire and rail the engine is on the point of slipping. The committee of the Master Mechanics Association in its report says: An examination of the tire wear shown in Figs. 148 and 149 shows no dis- tinct relation between the worn spots and the curves of maximum pressure of the wheels as given in Figs. 6 and 7. A very clear relation can, however, be traced between the worn spots and the parts of the wheel where the greatest coefficient of slip is combined with the heaviest wheel pressure. Local peculiarities of the tire, such as soft spots in it, as well as flat spots caused by slight sliding, affect the final contour of the worn tire, and it is only by taking the average wear at the same point on a large number of tires that the irregularities due to general conditions show themselves with the necessary clearness. Referring to the diagram of the average wear of the tire of the fifty-three ten-wheel freight engines shown in Fig. 148, first we will consider the wear of the front and back tires only, as these wheels were overbalanced, the main wheel's being underbalanced, and, on account of the effect of the angularity of the main rod, subject to quite different conditions from the others. Directing our attention to the wheels on the right side of the engine, an inspection of the figure shows quite uniformly, in both right forward and back tires, two locations of maximum wear, one beginning at about 160° and attain- ing its maximum at 220° or 230°, the other becoming pronounced at about 10° or 20° and attaining its maximum at about 50°. It will also be noticed that both of these low spots are connected from 220° to 50° in the direction of rotation by a portion of the tire much more worn than that portion from 50° to 220°. To understand the cause of this irregular wear, it is necessary to bear in mind that there are at least two ways in which driving wheels are slipped : first, when the slipping is slightly but distinctly noticeable, extending through but a small portion of the revolution; second, when the hold on the rail is entirely * Proceedings Am. Ry. M. Mech. Assn., Vol. 28. 198 STEEL RAILS MAIN TIRE FRONT TIRE BACK TIRE MAIN TIRE FRONT TIRE BACK TIRE RIGHT DRIVERS^, LEFT DRIVERS^ WEAR ON TIRES o © J ^^^ V — V / v S \ S COEFFICIENT OF SLIP. E NGINE JUST STARTINO. — ^^"v .12 OH COEFFICIENT OF SLIP IO MILES PER HOUR. COEFFICIENT OF SLIP 4-0 MILES PER HOUR =?- COEFFICIENT OF SLIP 60 MILES PER HOUR Fig. 148. — Tire Wear, Ten-wheel Engines. (Am. Ry. M. Mech. Assn.) STRESSES IN THE RAIL 199 FRONT TIRE 'd BACK TIRE £ £1 RONT TIRE £ > RIGHT SIDE. * tf,W" " ////A j^wt mm / /////////X///////// A/ ///////// Vleft side. WEAR OF TIRES RIGHT DRIVER^. 'X F r A3 ^^ y^ ~^ / N / \ s \ / \ / \ / \ / \ / \ / \ / \ s V y w V- V- '" *^ COEFFICIENT of slip engine JUST STARTING / \ y \ / \ ^ \ / v / - \ 51 / s^ \ -0 COEFFICIENT OF SLIP 40 MILES PER HOUR / \ / ^ / \ ^\ S — ^ ^""~ \. / V ' X y — -^^\ , COEFFICIENT OF SLIP 60 MILES PER HOUR Fig. 149. — Tire Wear, Eight-wheel Engines. (Am. Ry. M. Mech. Assn.) 200 STEEL RAILS broken, and the wheels slip through a number of revolutions, usually turning with considerable velocity. The first case, of slipping through but a small part of a revolution, occurs almost without exception on heavy pulls at slow speed, often being seen when an engine is pulling hard on a hill with just enough sand being used to avoid serious slipping, but not enough to prevent a slight slip at points where the rotative force is the greatest. The beginning of slip must occur under these conditions at or near the maximum of the coefficient of slip. Referring to Fig. 148, we find a maximum value of the coefficient of slip at 40° to 50°, and 130° to 140° with engine just starting. At 20 miles per hour, the maxima are at 40° and 130°, and at this speed the tendency to slip at 100° is also almost as great as at the other points. The figure shows a small spot following 100° on the front tire, but none is seen on the back. The diagrams on Fig. 7 indicate the cause, as the pressure of these wheels upon the rail at 100° is almost at a minimum and is much less than at 140° to 160°. It is also noticeable that the amount of wear following 160° is greater than that following 40° or 50°, for the same reason. This variation in pressure upon the rail increases rapidly with the speed, and Fig. 7 shows very clearly that following 40° the pressure of the front and back wheels on the right side decreases very rapidly, while the reverse is the case following 160°. The same conditions as to pressure on the rail occur, for the left-hand front and back wheels, just 90° back of those on the right side, and irregularities of wear produced by the drivers slipping through a number of revolutions at consid- erable velocity should occur on the left wheels at points 90° back of the corre- sponding point on the right wheels: 90° back of 40° is 310°, and 90° back of 220° to 230° is 130° and 140°. Fig. 148 shows the greatest depth of wear of tires of the left front and back wheels to be almost exactly at these points. There is also a small spot worn at 40°, due to the slipping at slow speeds when the influence of the counterbalance is nil. The irregularities of wear of the main wheels follow the same law as those of the front and back wheels, but the conditions are considerably modified by the difference in pressures caused by the influence of the angularity of the main rod, and to a less degree from these wheels being under- instead of over- balanced. The spots caused by the slight slipping at slow speeds at about 40° and 130° should be found in these wheels as in the front and back wheels, unless the accompanying condition of necessary pressure is absent. Fig. 7 shows from 16,500 to 17,000 pounds at 40° on the right main wheel, and from 12,700 to STRESSES IN THE RAIL 201 17,500 pounds on the left wheel at the same point, indicating greater wear on the right than on the left tire at this point, which the diagram, Fig. 148, shows. The wear at 130° is found in these wheels, but, owing principally to the influence of the angularity of the main rod and partly to the wheels being underbalanced, the conditions of pressure following 130° on the right main wheel are very dif- ferent from those of the right front and back wheels. Fig. 7 shows that the pressure on this wheel is always rapidly decreasing following 130°, instead of increasing, and, consequently, the worn spot at this point extends but a short distance in the direction of rotation. Not so, however, with the left main tire. Here the pressure is always increasing following this point, and the figure shows the great elongation of this spot in the direction of rotation, extending it as far as 210°, while that on the right tire extends only to 165°. There still remains to be explained why the heavy spot on the main tire should slightly precede the point of the maximum coefficient of slip at 130°, and why that on the left wheel still farther precedes this point and, in general, is greater than on the right. An inspection of the diagram on Fig. 7 shows that the pressure of the right main wheel on the rail is always greater preceding than following the 130° point. Fig. 148 also shows that the coefficient of slip is high as early as 110° after a speed of 10 miles per hour is attained, and increases but slightly to its maximum at about 130°. Any slipping occurring between 110° and 130° will, on account of the pressure, cause a serious spot at this point on the main wheels, which the diagram shows. Fig. 148 shows the worn spot under consideration on the left tire, not only elongated in the direction of rotation, which is explained by the difference in pressure in this direction, but also in the opposite direction, extending beyond the 80° point. This is doubtless due to the slight slip caused by the main rod passing the forward center and suddenly thrusting this wheel back an amount equal to the lost motion in the bearing shoe and wedge. The same thing occurs, of course, on the right wheel, and the sharp, but slight, wear following the 350° point shows it quite clearly. On the left wheel, however, this wear is imme- diately followed by the more serious one due to the approach of the maximum point of coefficient of slip from 110° to 130°, and becoming merged into it, both are increased. The upper diagram on Fig. 149 shows the wear of the tires on the engine for which the calculations are plotted on Fig. 6 for the eight-wheel engine. This shows in a general way the same characteristics of the average wear for the fifty-three ten-wheelers, shown on Figs. 7 and 148, but is, undoubtedly, affected to a considerable extent by unknowable local conditions. Here the front wheels, 202 STEEL RAILS of course, correspond most nearly to the main wheels on the ten-wheeler, and here, as there, the left main tire shows the most serious irregularity of wear. The committee presented the following conclusions as a result of its investi- gation, which it should be borne in mind was in connection with much lighter wheel loads than obtain at the present time. " There is no doubt locomotive tires wear without slipping, and there should be, and probably is, a portion of the irregular wear due to the pulverizing or crushing action being greater under heavy than light loads. " An experiment was made by removing all the overbalance in the counter- balance of an engine, when the irregularities of wear in the main wheel were almost exactly duplicated in location and to a remarkable degree in magnitude. This, together with similar experiments attended by the same general results, leads us to believe that the irregularities of wear of the tire are almost wholly caused by abrasion from slipping, and that the pulverizing of the steel from pressure alone is of secondary importance." With the smaller wheels under the cars and locomotive tenders the con- ditions are quite different.* The smaller steel wheel or tires do not render as satisfactory service under heavy loads and high speed as the larger locomotive tires, principally for the reason that the manufacturer is not able to put into the small tire sufficient mechanical work to obtain uniform physical properties for the full circumference of the tire, and in the service portions of the tread thickness. The experience with 36-inch steel-tired wheels under locomotive tenders illustrates this point. The steel tender wheels have failed by shelling out, and portions of the metal of inferior physical structure on one-third of the circum- ference have worn so as to make an eccentric tire which has caused such severe impacts on the rail as to require the removal of the wheels after a short service. The average load on these wheels is 18,000 pounds, and the maximum static load 20,400 pounds; many of them give only six months' service, or 30,000 miles, after a first or second turning. In a paper read at the last International Railway Congress, published in the Bulletin of October, 1911, Dr. P. H. Dudley has proposed a new method of measuring the tonnage service of rails and wheels. He explains that the ton- nage supported by a given portion of the bearing surface of a rail due to a pass- ing wheel is the total load multiplied by the number of wheels passing over it. The tonnage sustained by the metal in the treads of the wheel is the total wheel load multiplied by the number of revolutions, and this tonnage accumulates * Railway Age Gazette, December 22, 1911. STRESSES IN THE RAIL 203 more rapidly than that of the rail. It is greater also as the diameter is less and the number of revolutions larger, so that the tonnage service of 36-inch tender wheels is much greater than that of the 75- or 80-inch drivers, though the loads on the latter may be much larger. The pressure and movement of heavy loads on the rail causes a cold rolling to take place on the head of the rail, which tends to expand the metal and, if the rail were free to move, would cause it to assume a curved form with the head on the convex surface.* As the rail cannot bend, this cold-rolled metal is subjected to a compression stress. A tensile component would be expected in the vicinity of and next below the part which was affected by compression strains, and this has led to a theory of the cause of the oval silvery spots or transverse fissures in the head of the rail observed by Mr. Howard, f These rail fissures which resemble the smooth surfaces of a progressive fracture have so far been largely confined to one steel company. The theory advanced as to their probable cause should not be regarded as final until further substantiated, and many engineers feel that it is not the true explanation. No other adequate reason has been offered as yet to explain their formation, although a careful inves- tigation is being made which will doubtless throw further light upon the subject. Mr. Howard J states that: " The flow of the metal of the head, appar- ent to the eye and witnessed very generally in portions of the track, may be taken as evidence of exhausted ductility of the metal. The ability of the steel to elongate, as found in the primitive state of the rail before going into service, is lost by reason of its development, and the rail, at first tough and capable of being bent, is now brittle and will bend only to a limited extent before rupture. " The brittleness is due to the flow of the metal at or immediately below the running surface of the head. The structural continuity has not been de- stroyed, as may be shown upon annealing the metal, which effects a restoration in its ability to elongate. A rail from service will not bend well with the head on the tension side, since the surface metal has been subjected to cold flow in advance of its being worn away by abrasion." * Mr. Howard found that in the case of a rail, exposed to this action, on cutting off the head from the web, the former sprung into a curved shape with the running surface on the convex side. The deflection at the middle of the length of the piece, 5 feet long, was 0.20 inch. It is probable, however, that some of this curvature was caused by the strains set up in the rail when cooling. t Appendix to Report by the Interstate Commerce Commission on Accident to a Lehigh Valley Railroad Train at Manchester, N. J., on August 25, 1911. See also Broken Lehigh Valley Rail, Iron Age, Vol. 88, Part 2, p. 800. t Some Causes Which Tend toward the Fracture of Steel Rails. James E. Howard, Journal Association of Engineering Societies, July, 1908. 204 STEEL RAILS Removing the surface metal, in the planer, restores the bending quali- ties of the rail, but in this case it is necessary to plane away the metal from the sides as well as from the top of the head, that is, as far down as the cold flow has taken place. The difference in the bending qualities of the same rail according to the head being on the tension or compression side is shown by Fig. 150. The Fig. 150. — Two Pieces of a Worn 100-lb. Rail after Testing. The upper piece, with head on compression side, bent 21 degrees with- out rupture. The lower piece, with head on tension side, bent 4| degrees and then ruptured. (Howard.) upper piece of rail in the figure was bent with the head in compression, while the lower one had the head on the tension side of the bend. Rails of this series of tests have ruptured with a deflection of only 3 to 5 degrees when the head was in tension, but remained unruptured when bent through an angle of 20 degrees or more with the base in tension. After an- nealing these old rails, of exhausted toughness, the bending qualities were restored, after which the rail could be bent in either direction through about the same number of degrees without fracture. STRESSES IN THE RAIL 205 The effect of the exhausted metal in the head is well illustrated by Table XLVIII, which presents some of the results of Kirkaldy's tests on rails. * Kirkaldy states that " the rail appears to have been gradually hardened under the action of the traffic, more especially on the immediate skin or surface, until the steel thereon cracked under the upward flexion of the rail in the regions just over the chairs, or the minute cracks may have been induced by the severe action of the brakes on trains, so to speak, tearing up or disintegrating the surface of the steel." TABLE XLVIII. — BENDI VG TESTS ON WORN RAILS. (Kir kaldy.) (Dis aneebetwc en supports 5 feet, load applied a t center) Weight Dime nsion, Stress. Deflection. Depth. Web. Elastic. Ultimate. At 40,000 rT ... Pounds. Ultl Pounds. Inches. Inch. Pounds. Pounds. Inch. Inc hes. Worn rail; 80 lbs. main line, 23 Same, tested inverted. | 77.62 5.00 .65 1 35,700 60,780 58,240 0.62 8 0.59 4 19 Removed uncracked. Snapped. New rail. Same, tested inverted. J 85.41 5.50 .68 ( 44,300 1 43,500 78,840 77,350 0.26 8 0.28 6 5 Removed unciackeJ. Removed buckling. Worn rail; 85 lbs., in road 5 vears with heavv wear. Same, tested inverted. ( 84.25 5.43 ... ( 47,800 ( 47,800 88,130 0.24 8 0.24 6 5 Removed uncracked. Removed buckling. Worn rail; 82 lbs., 10 years, ser- Same, tested inverted. j, M 4.95 .66 ( 40,000 ( 40,000 73,130 55,260 0.31 8 0.31 1 44 Removed uncracked. Snapped. Worn rail; exposed to brake | 74.70 4.86 .66 ( 35,400 ( 31,500 61,440 35,400 0.64 7 36 Removed uncracked. Snapped, slight flaw. The slipping of the driving wheel of the locomotive when starting a train may cause roughness of the metal of the rail, accompanied by intense heating of the immediate surface metal of the head. In addition to the loss in ductility of the steel by reason of its flow under the wheel pressures, the metal at the running surface is hardened through this action of the wheel. Showers of sparks attend instances of this kind, from which the high temperature acquired by the particles of the steel may be judged of. There follows also a sudden reduction in temperature through conductivity of the cold metal below, which has an effect similar to quenching steel from high temperatures in water or other quenching liquids, and there results a surface hardening of the metal. During this period of hardening the surface metal is placed in a state of intense tension, relief from which is obtained by the development of cracks in the steel. A very interesting experiment is reported by Wickhorst f on the flow of metal in the rail head under the wheel load. The test was made to determine, * Kirkaldy on Effects of Wear upon Steel Rails, Appendix II. Min. of Proceedings of the Inst, of Civil Engrs., Vol. CXXXVI, January, 1899, p. 166. t Flow of Rail Head under Wheel Loads. M. H. Wickhorst, Proceedings Am. Ry. Eng. & M. of W. Assn., 1911, Vol. 12, Part 2, p. 535. 206 STEEL RAILS if possible, what change is made in the microstructure of the head of the rail by the rolling over the rail of heavy wheel loads. At the same time, measure- ments were made of the spread of the head and the width of the bearing produced. The test was made on a new 70-pound Bessemer rail with a reciprocating machine in which a piece of rail is moved back and forth under a wheel to which a load can be applied by means of levers. A diagram of the machine is shown in Fig. 151, from which it is seen that the rail is fastened to a steel bloom Fig. 151. — Reciprocating Machine for Testing Flow of Metal in Head of Rail. (Am. Ry. Eng. Assn.) which runs on rollers running on another steel bloom that forms the bed of the machine. The rail bed is connected by means of a connecting rod to the bed plate of a planer, which furnishes the power to run the rail machine. The weights applied to the weight hanger are multiplied 600 times, as applied to the axle of the wheel. The piece of rail tested was 12 inches long, which was set up between two other similar pieces, which acted as end pieces onto which the wheel could roll when leaving the piece under test. The piece tested had the sides of the head planed vertical to a width of head of 2 inches. This width was used partly to accentuate the test and partly to do away with the rounded corner, so as to allow of measuring the width closer to the top of the head, and the sides were made vertical so the measurements could be made satisfactorily with a micrometer along the whole depth of the head. The section of the STRESSES IN THE RAIL 207 original rail and as tested are shown in Fig. 152. Before testing, the width of the head was determined at the top, at the bottom and halfway between, both at the middle of the piece tested and at one end, by means of a micrometer. To determine the sag of the head, two prick-punch marks were put on each side of the rail at the middle of its length, one on the side of the head near its bottom and the other on the top side of the base, about f inch from the web. In order to have a vertical side on which to prick-punch the mark, the base was gouged at the desired place. The distance between the marks was measured in .01 Fig. 152. — Section of 70-lb. Bessemer Rail Tested for Flow of Head. (Am. Ry. Eng. Assn.) inch by means of a fine-pointed toolmaker's dividers and a steel scale reading to .02 inch. The test was started with a load of 30,000 pounds applied to tie wre< using 1000 double strokes or 2000 rollings of the wheel over the rail ur_c t test. The bearing assumed a width of .64 inch. The only effect on the width of head was to spread the top of the head .002 inch, and the load was, there- fore, increased at once to 60,000 pounds and the test continued until the head seemed to no longer spread as measured with the micrometer. The width of the head of the rail and the width of the wheel bearing on the rail, st various stages of the test under the load of 60,000 pounds, are shown in Table XI IX. The spread of the top part of the head and the width of bearing in this table 208 STEEL RAILS includes also the effect of the preliminary rolling of 2000 wheel applications with 30,000 pounds. The head did not show any sag throughout the test. TABLE XLIX.— ROLLING TESTS ON RAIL HEAD WITH LOAD OF 60,000 POUNDS Width of Spread of Head. Wheel Rollings. Middle of Rail. End of Rail. Top of Head. Middle of Head. Bottom of Head. Top of Head. Middle of Head. Bottom of Head. 200 2,000 4,000 23,460 32,142 .92 .92 .94 1.02 1.04 .002 .009 .010 .013 .013 .000 .003 .004 .006 .006 .000 .000 .001 .001 .001 .004 .006 .006 .008 .008 .002 .002 .002 .003 .003 .000 .000 .000 .000 .000 It should be remarked that the wheel was beveled some, and the bearing was, therefore, on one side of the top of the head, remaining throughout about .2 inch from one side and increasing in width toward the other side. A microscopic examination was made of the rail at the top of the head and at the center of the head both before and after rolling. While the micro-photo- graphs obtained indicated a slight stratification of the grains in a longitudinal direction, there was little, if any, difference between the specimens before and after rolling. The material tested was good ductile material of medium hard- ness for rail steel, and as the maximum lateral stretch at the top of the head was only .013 inch, much difference in the microstructure could hardly be expected. It is evident that the metal in the head of the rail must have a high elastic limit to successfully meet the severe conditions of modern service. This fact was clearly brought out several years ago by one of the writers in connection with some service tests on annealed rails on the Philadelphia and Reading Rail- way. An account of this investigation appears in the Proceedings of the New York Railroad Club, December, 1906. Eleven 90-pound rails were sawed into halves, and one half of each rail was annealed. The carbon content averaged 0.54 and the manganese 1.06 per cent. After 88 million tons traffic it was found that the annealed rails averaged 31.9 per cent more wear and they also showed a greater tendency to crush and splinter, but it was found on test that the elastic limit had been reduced over 10 per cent. The annealed rails, in spite of their finer structure and consequent greater toughness, did not wear so well on account of the lower elastic limit. In Article 9 attention was called to the effect of the inertia of the track on the stresses produced by impact, and in Article 8 it was shown how the lack of round- STRESSES IN THE RAIL 209 ness of the wheel may cause excessive strains in the running surface of the head. These factors make it much more difficult to control this stress than that produced by bending; in the latter the forces acting on the rail can be determined within closer limits and the remedy is easier to apply. The rail is in fact called upon to perform two quite distinct functions, one of which is to resist the strain produced at the area of contact between the wheel and the rail and the other to resist the bending stress; the latter can be reduced by increasing the moment of inertia of the section or strengthening the track structure, but the former is in a measure independent of the form of the rail and requires a change in the character of the material of which the rail is composed. The defect known as "roaring rails" is caused by an imperfect surface or corrugations in the head of the rail. These corrugations are confined almost exclusively to the rails used on electric roads and few problems, confronting the maintenance of way engineer of such roads, have attracted the attention and study being given to this trouble. There are many conflicting opinions as to the cause of the phenomena, none of which appear adequate to properly explain it.* The corrugations of rails in recent years have increased rapidly in number; once they start they rapidly grow worse and it is important to remove them as soon as the indentations appear. This is generally accomplished by means of a rail grinding device which consists either of a carborundum block rubbing over the rail or an emery wheel which grinds the rail to a true surface. The cost of removing corrugations in rails varies from a few cents to 50 cents per foot of rail, depending on the depth of the waves; fortunately after the corrugations have been removed there is little probability of their ever returning. * Some of the recent literature on this subject is as follows: Andrews, J. H. M. — Some notes on rail corrugation. 1500 w. 1910. (In Electric Rail- way Journal, Vol. 36, p. 370.) Outlines prominent causes of corrugation and presents a few notes and conclusions. Busse, A. — Rail corrugation. 1500 w. 1910. (In Electrician, Vol. 65, p. 930.) Observations from many points indicate strongly that corrugation is due primarily to defects in the rail metal, resulting from the rolling. Panton, Joseph A. • — Rail corrugation. 26 p. 111. 1907. (In Journal of the Institution of Electrical Engineers, Vol. 39, p. 3.) Concludes, in summary, that corrugations are caused, directly or indirectly, by lateral play in weak trucks, the weakness being intensified by unsymmetrically driven axles. Wilson, C. A. Carns. — Rail corrugation. 3000 w. 111. 1908. (In Engineering, Vol. 86, p. 90.) Aims to show conditions under which corrugations are produced. 210 STEEL RAILS 21. Proposed Solutions of the Bending Stress in the Rail Following the path of the forces as they pass through the rail and are distributed to the ties, we find very complex and unstable conditions. The rail is supported on a series of yielding supports. These supports, through their unequal yielding, bring about distributions of stress in the rail that are difficult to calculate. Before proceeding further with the discussion of this subject, let us turn to some of the methods advanced for the proper solution of the problem. * Mr. 0. E. Selby approaches it in the following manner: " Examining first the bending stress in the rail, we have 50,000-pound axle loads on supports 20 inches apart. For these conditions the American Railway Engineering and Maintenance of Way Association specifications for steel bridges, paragraph 5, call for 100 per cent impact, making the stresses equivalent to those from a 100,000-pound axle load, or a 50,000-pound wheel load. " For a simple beam the bending moment in one rail would be 250,000 inch-pounds. For a continuous beam with rigid supports, it would be two- thirds that, and for a continuous beam with partially yielding supports, three- fourths of the bending moment for a simple beam is reasonable, giving 187,500 inch-pounds. If we consider the wheel placed over a tie which yields enough to carry one-fourth of the load to each adjacent tie, the resulting moment in the rail is the same. The section modulus of an 80-pound A. S. C. E. rail is 10.0, making the extreme fiber stress 18,750 pounds per square inch. For a 100-pound rail the unit stress is reduced to 12,800. " Passing to the load on the tie, we encounter an element which must vary between rather wide limits with the stiffness of the rail and yielding of the supports. With a simple beam and load placed midway between the sup- ports, the reaction on each support would be one-half the load. The theory of the continuous girder would make the reactions about 55 per cent to 67 per cent, depending on whether the load is placed over a support or midway between. " The yielding of supports would undoubtedly reduce these percentages. Bridge specifications usually consider the load equally distributed among three ties, but bridge ties are spaced usually 14 inches between centers, so that, if the load going to one tie is proportioned to the tie spacing, the amount for 20-inch spacing would be 20 -=- 14 x 1 -f- 3 = 20 ■*- 42 = 47.6 per cent. There- * O. E. Selby, Bridge Engineer, C, C, C. & St. L. Ry. A Study of the Stresses Existing in Track Superstructures and Rational Design Based Thereon. Proceedings Am. Ry. Eng. & M. of W. Assn., 1907, Vol. 8. STRESSES IN THE RAIL 211 fore, the assumption that the maximum load on a tie is half the axle load seems a proper one. " Modern specifications call for an E-60 loading, which contains 60,000- pound axle loads, spaced 5 feet between centers. A tie spacing equal to one-half the wheel spacing would load the girder (rail) at the quarter points and produce moments (in a simple beam) equal to those produced by a uniform load. " A more practicable tie spacing, one-third of the wheel spacing, would similarly produce moments j2 P ar t, or only 1.4 per cent greater than those from a uniform load, so that if we design a rail for a uniform load equal to the wheel load divided by the wheel spacing, the result would be very nearly correct. The wheel load with impact is 60,000 pounds, or 1000 pounds per linear inch of rail. For a continuous beam (indefinite number of spans and loads) the maximum movement is 1 h- 12 x WL 2 = 1 -f- 12 X 1000 X 60 2 = 300,000 inch-pounds." The following has been presented by Mr. Bland : * " The rail acting as a beam under passage of wheel loads is in a condition of ' restrained ' ends, and the maximum moment from a wheel load Q is given by M = ± | Ql, ' Q ' being concentrated load and ' I ' being span center to center of ties. The moment alternates from positive to negative, and alter- nates equally. The dynamic augment to static wheel load is taken 60 per cent for a speed of 75 miles per hour. " Assume a static axle load of 60,000 pounds, giving static wheel load of 30,000 pounds. The dynamic augment for 75 miles per hour is 60 per cent, making a dynamic wheel load of 48,000 pounds." TABLE L. — RAIL STRESSES. (Bland.) Rail Weight. Tie Spacing, c. toe. =2. Minimum Rail Modulus=Z. Dynamic Moment. Resulting Unit Stresses. Pounds per Yard. 60 70 85 100 24 24 22 22 6.70 8.30 11.30 15.00 Inch-pounds. 144,000 144,000 132,000 132,000 Lbs. per Sq. In. 21,500 17,350 11,680 8,800 The following investigation of the stresses in the rail was suggested by Mr. F. B. Freeman, in a paper presented to the New York Central Lines Main- tenance of Way Committee entitled " Investigation of Stresses in Track Super- structure." This paper is of considerable interest, as the results obtained by * J. C. Bland, Engineer of Bridges, Penn. Lines West of Pittsburg, on the Capacity of Modern Heavy Rail for Existing Heavy Engines, 1907. 212 STEEL RAILS the methods proposed are compared with the stresses actually given by test of the rails under the moving trains. An abstract of the paper follows: By means of plotted curves recently published showing resultant wheel loads in terms of the unit static loads at various speeds, Dr. P. H. Dudley shows as a result of his experiments that with' smooth wheels rolling without accelera- tion, the impact approaches 50 per cent as a limit at 100 miles per hour. A curve of resultant wheel loads at various speeds with acceleration shows 100 per cent impact as the limit at 100 miles per hour. At speeds of 50 to 70 miles per hour the impact appears to be about 75 per cent when the train is under acceleration. By acceleration it is meant that the locomotive is exerting its maximum tractive effort at that speed. From his stremmatograph tests, Dr. Dudley finds that the maximum extreme fiber stresses in the 100-pound rail under the present Class " I " loco- motive (Atlantic type) sometimes run as high as 22,000 pounds, while with the 80-pound rail stresses as high as 28,000 pounds are not uncommon. One thing, however, must be borne in mind : though the extreme fiber stress in steel rails may seem high as shown by test, these maximum stresses are of very short dura- tion, lasting but a small fraction of a second and often reversed immediately. Within certain limits the stress seems to vary directly as a function of the speed ; hence the greater the speed, the greater the stress, but the shorter its duration. The present steel rails have an elastic limit between 50,000 pounds and 60,000 pounds and an ultimate strength of 110,000 pounds to 120,000 pounds as shown by test. If we investigate the stresses which are supposed to exist under the Class "I" locomotives and then compare the resultant stresses with those of tests, we may arrive at a conclusion regarding the trustworthiness of our assumption. As the Atlantic type of locomotive (Class " I ") cannot draw an ordinary train at a greater speed than 70 miles per hour with acceleration, we are justi- fied in using 75 per cent impact in investigating the existing stresses under Class " I." The Pacific type (Class " K ") and the electric locomotive (Class " T ") each may haul trains at speeds approaching 100 miles per hour,* and the former will be investigated with 100 per cent impact. As the wheels roll along the rail there is a general depression of the track, local depressions being greater under the heaviest concentrations, and fairly uniform where the wheel loads are equal and evenly spaced. According to * This statement seems open to question; compare with Article 3. STRESSES IN THE RAIL 213 Dr. Dudley, this general depression varies from .10 inch to .20 inch, varying with the stiffness of the rail, elasticity of subgrade, and tamping of ballast. Due to the deflection of the rail, there will De a greater depression under the wheels and the lesser depression about midway between them. The tie pressure may be assumed proportional to the tie depression, and from the tie pressure the stress in the rail may be approximated. In considering the deflection of the rail, we may consider the rail as a con- tinuous beam being supported by the wheels and having varying concentrated loads applied by the ties. These concentrations decrease toward the center of the span and give an effect practically similar to that of the uniform load, equivalent to the sum of the tie pressure (Fig. 153). Fig. 153. — Distribution of Tie Pressure under Rail. (Freeman.) In order to approximate the rail deflection, there will be no great error in considering the load of the drivers and second wheel of the first truck as uni- formly distributed from a point between the two wheels of the forward truck to a point midway between the rear driver and the trailer; likewise that the load of the trailer be distributed from a point midway between the rear driver and the trailer to a point midway between the trailer and the first wheel of the tender. The load of the drivers of the present Class " I " locomotive, including impact, is 96,000 pounds, which will be distributed over approximately 19 feet, giving an equivalent uniform load of 6400 pounds per lineal foot. Under the trailer the equivalent uniform load will be 4000 pounds per lineal foot, and under the front wheel about 3000 pounds per lineal foot (Fig. 154). Under the drivers we have a span of 7 feet and a uniform load of 6400 pounds per lineal foot. With the 100-pound rail this loading would cause a deflection of .047 inch and with the 80-pound rail a deflection of .08 inch. The average uniform load between the rear driver and the trailer being about 5000 pounds per lineal foot, the deflection of the 100-pound rail becomes .127 inch, while the 80-pound rail deflects .22 inch. It will be seen by a glance at Fig. 155 that the tie reactions vary with the stiffness of the rail, being much more uniform with the heavier rail. STEEL RAILS 6 o in r .Q 7 O O 9. ° O m o o o o O m ^i 9 '- 2 " c i - o 6 O 10 r^ to cu - =? 7 J o 6 o o o o o o o N - S CM CM (0 "\\0'-7Vz [ . . »9'- 7 ^ + £ + ^ O Q OO O O O O O OQ OO O mo m :r O - N. oo mo "in w CM -^ CM QEI D = CM ■\f; Cb E = Modulus of elasticity of the rail, / = Moment of inertia of the rail, b = The width of the tie, 1= One-half the length of the tie, C = Coefficient of the ballast, z = An auxiliary value depending on the form of the tie. The coefficient of ballast represents the pressure in kilograms per square centimeter of the ballast which causes a depression of one centimeter. The coefficient 3 corresponds with simple gravel and the coefficient 8 with gravel on a bed of dry stone or on rocky soil. Fig. 158 shows that the ratio — Q increases with y , that is to say, with the stiffness of the rail and the flexibility of the tie. Table LI 1 1 presents calculations for several German railroads by the aid of Zimmerman's formulas. The table is taken from an article on " The Track Superstructure of German Railways " by M. Blum in the Revue Generale * Calculation of the Superstructure, Berlin, 1888. 218 STEEL RAILS des Chemins de Fer, No. 5, November, 1908, a translation of which is given in Proceedings American Railway Engineering and Maintenance of Way Association, Vol. 11, Part 2, 1910. V O 1 2 3 4 0.7 s s DQ \ \ \ | | "-, 1.5 •y=o i 2 Fig. 158. — Bending Moment of Rail placed o Ties. (Zimmerman.) In questions of such moment we cannot rely on mathematical analyses for conclusions. We can deduce general results from specific experiments by their aid, but it is somewhat unsafe to attempt any generalization on its evidence alone. 22. Tests to Determine the Bending Stress in the Rail * Experiments were made in the track of the Boston and Albany Railroad in 1889. The experiments consist in measuring the depression of the rail at different places along the length when loaded, and in measuring the extension or compression of the metal at the upper surface of the base of the rail, near the edge of the outside flange. For measuring the depression a row of stakes was driven alongside the track, three feet away, and the relative level of points on the base of the rail and nails in the tops of the stakes was ascertained by means of a sensitive spirit level. For ascertaining the strains, gauged lengths of 5 inches each were estab- lished and defined by center punch marks on the base of the rail at places over the ties and midway between them, and the amount of extension or compression, as the case might be, was measured on these gauged lengths. The rails were 72 pounds per yard, 4£ inches high and 4£ inches width of base. The results of the experiments are shown in Fig. 159. * House Executive Documents, 1st Session, 51st Congress, 1889-90, Vol. 25, Tests on Metals. TABLE LIII. — ] DIMENSIONS , WEIGHTS, AND COST OF DIFFERENT SYSTEMS OF TRACK SUPERSTRUCTURE ON WOODEN TIES 2 S | 4 | 5 • 10 11 1. | 13 » 1 " 1 " 1 " 18 19 20 21 22 | 23 | 24 | 25 2S 27 - \*\m\*\m\u\u\m\ Rails. Ties. Anglo Bars. Weight of Track. 1 | 1 Rail, Ties. Angle Bar*. Comparison. o is 1 & 1 1 Spacing. I Per Pair. I 1 i J 1 j j 1 | 1 1 Deflection. l 1 5 1 Rails. Ties. | Angle Bars. 1- Type of Rail, Etc. a j 1 j'! Center, Eitrera- i § | 3 j B H r tifgSta Referred to Point per'' Ia.« Ft. Feet and laches. . Ia. .. La. Lbs. In.<: Lbs. Yard. % % % perlcS. K' Lbs. In. A la. la. L, See Note. With Prussian Track, Type 6a, No. 1 of Table. Prussian Hessian Rys. ) Type 6a, 1885-94 J Prussian Hessian Rys., 1 Type 6e, 1885-99 ( Prussian Hessian Rys., ) Type 8a, 1890-94 J Prussian Hessian Rys., 1 Type 8b, 1890-99 J Prussian Hessian Rys., I Type 15a, 1905 ) Alsace-Lorraine Rys., 1 Type of 1893 J Alsace-Lorraine Rys., ) Type 1893-1903 ( Bavarian State Rys., 1 Type of 1892 J Bavarian State Rys., i Type of 1898 J Saxony State Rys., 1 Type of 1890 J Saxony State Rys., Rail 1 with reinforced joint | 67.1 67.1 82.4 90.5 76.0 70.1 87.4 91.9 91.9 24.88 32.45 32.45 37.99 26.21 26.21 25.72 34.97 40.80 40.80 39.37 39.37 39.37 39.37 49.21 29.53 39.37 29.53 39.37 32.81 49.21 15 18 15 17 24 12 19 12 18 13 19 8' 10|"X10i''X6A" 8' KH"Xl0i"X6ft" 8' 10i"X10i"X6&" 8' 10r'Xl0J"X6A" 8' 10i"X10i"X6- r y' 8' 10J"X10i"X6A" 8' 10rxl0|"X6&" 8' 2J"Xl0i"X6A" 8' 10J"X6A"X6A" 8' 2i"Xl0i"X6&" j*8' 2i"X10}"X6f " | 1|8' 10r'X10r'X6ft"j 33.45 27.56 33.45 30.32 24.80 31.50 32.13 30.04 32.48 32.48 20.87 19.69 22.05 20.87 21.20 23.62 13.39 9.69 16.54 21.20 21.20 27.17 31.10 28.35 32.28 35.04 34.65 34.65 [27.56] I 2 ' 1 "'' 1 '' 33.47 35.43 33.47 60.6 67.5 81.9 91.5 90.0 49.1 75.5 101.0 20.16 20.16 28.96 29.01 29.01 23.52 14.40 10.42 14.88 9.84 27.60 1.23 1.23 1.12 1.12 1.31 1.82 2.47 2.35 4.14 1.48 413.0 473.4 448.7 491.7 548.8 458.9 504.1 405.4 537.2 473.2 469.2 61.1 53.8 55.6 57.0 56.1 60.6 55.5 53.9 48.2 48.4 9.1 10.7 9.5 10.2 10.8 9.3 9.9 13.6 13.0 12.4 32.5 28.2 36.7 33.3 32.9 33.1 30.1 34.6 32.5 1.40-5 1.55] 1.56 | 1.66] 1.84] 1.53 | i*| 1.40 J 1.83 | 1.67J 1.67 j 108 108 289 289 108 289 108 289 108 108 289 108 108 289 17,570 14,000 16,490 13,310 14,970 11,920 14,420 11,620 13,550 9,480 16,360 13,020 15,400 12,460 17,630 14,020 14,000 13,200 10,760 13,200 10,760 0.143 0.074 0.122 0.059 0.132 0.067 0.122 0.059 0.100 0.051 0.135 0.069 0.115 0.057 0.146 0.073 0.119 0.061 0.127 0.066 0.127 0.066 620.0 746.6 617.2 630.0 613.0 607.2 635.6 600.0 601.5 620.0 701.0 508.6 612.8 504.8 600.0 605.7 624.2 550^3 493.4 550.3 0.146 0.070 0.142 0.059 0.144 0.065 0.142 0.061 0.140 0.057 0.145 0.066 0.141 0.059 0.156 0.071 0.142 0.060 0.152 0.065 0.152 0.065 0.016 0.016 0.015 0.013 0.016 0.015 0.015 0.014 0.014 0.013 0.016 0.015 0.015 0.013 0.026 0.022 0.015 0.014 0.025 0.020 0.025 0.020 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 +0 -0 -0 -0 +0 -0 -0 -0 015 018 015 015 015 016 015 015 014 015 015 017 015 014 007 0004 015 oi.-. 007 0004 007 0004 1479 1215 1245 1036 1147 976 1116 959 1136 962 1164 924 1409 1176 1968 2024 1539 1581 1486 1398 2189 917 '.).-,(; 760 793 4836 3973 4072 3386 4913 4181 4200 3007 3935 3334 4047 3213 2400 4261 5578 3373 4358 2037 2763 3350 2425 4240 3510 fi.ooj (l.llj }l,ll M }l,9j M li.oo (1.31J M I 1-19 ! 1.00 1.00 0.94 0.95 0.85 0.85 0.82 0.83 0.93 0.93 0^89 1.00 1.00 0.80 0.81 0.75 0.76 0.75 0.76 1.00 1.00 0.85 0.92 0.91 0^81 0.70 0.69 0.94 0.93 0>7 1.02 0.99 0.83 0.89 0.89 0.89 00 00 98 84 99 95 85 81 00 81 98 84 80 74 80 74 1 1 1 00 00 98 85 99 93 98 87 96 96 84 07 01. 98 85 04 92 04 92 1.00 1.00 0.84 0.85 0.78 0.70 0.79 0.77 0.79 0.79 0.76 0.95 0.97 1.33 1.37 1.27 1.30 1.00 1.15 1.18 1.30 0.62 0.65 0.63 0.65 1 1 1 1 00 00 84 85 02 05 87 91 81 84 84 81 61 61 88 15 10 61 70 61 289 289 108 108 108 108 289 108 2.S0 108 108 "a" = pounds per square iucli produc- ing 1 inch depres- sion in ballast. Inside angle bar. < lulside angle bar. Inside angle bar. ( tulside angle bar. Inside angle bar. I lul side angle bar. lu-ide angle bar. Outside angle bar. Sellew, " Steel Rails." • Iatermediat a ties. t Joiat ties. Note."— Columns 26 and .27 are, shown ir nits, the original table not indicating what n STRESSES IN THE RAIL 219 * Experiments were made by the Ordnance Department, U. S. Army, during the month of October, 1893, on the track of the Chicago, Burlington and Quincy Railroad, at Hawthorne, 111. The experiments consisted of measuring the depression of the rails under the weights of different classes of locomotives, and the fiber stresses developed in the base of the rail. For the purpose of observing the depression of the rails, bench marks were established on a row of stakes driven alongside the rail, 31 inches distant from DEPRESSION OF RAIL STRAINS IN BASE OF RAIL 5" LENGTH COMPRESSION Fig. 159. — Railroad Track Experiments, Boston and Albany R. R. it. A beam carrying a micrometer and an astronomical level bubble were used in observing the depression of the rail (see Fig. 160), 'first measuring the height, using points on the outer flange, when the rail was unloaded, and repeating the observations when the engine was standing on the track. It was found that the roadbed in the vicinity of the locomotives was sensibly depressed and that the bench marks were within the influence of that depression. It was possible to detect a depression of the roadbed as far as 91 inches from the locomotive at the side of the track. A correction for the depression of the bench marks was obtained by means of a cantilever supported 10 feet from the track, and the total depression of * House Executive Documents, 3rd Session, 53rd Congress, 1894-95, Vol. 30, Tests of Metals, etc. 220 STEEL RAILS Fig. 160. — Railroad Track Experiments. Photograph of Leveling Instrument for Measuring the Depression of the Track. Fig. 161. — Railroad Track Experiments. Photograph of Micrometer for Determining the Fibre Stress in the Base of the Rail. STRESSES IN THE RAIL 221 points on the rails was also determined with reference to the cantilevers in some of the experiments instead of using stakes. The fiber stresses were determined in the base of the rail by measuring the elongation or compression of the metal on a gauged length of 5 inches, established on the top surface of the outer flange, observing the strains when the wheels were directly over or when spanning the gauged length (see Fig. 161). The observed strains were then computed for the stresses per square inch, assuming a modulus of elasticity of 30,000,000 pounds per square inch and that the fibers in the base were strained proportionally to their distance from the neutral axis of the rail ; the computed stresses referring to the outside fibers most remote from the neutral axis. It will be observed that the strains and the computed stresses refer to a gauged length of 5 inches, and, consequently, the maximum stresses may be somewhat greater than those shown, considering the maximum bending moment to be directly under the point of application of the load. Some of the results are graphically shown in Fig. 162. The moment of inertia of the 66-pound rail tested was 19.127 and the 19.127 section modulus of the base ? '„, = 8.54. Fig. 162A shows the depression of one rail its entire length and the ends of contiguous rails, the locomotive occupying one position thereon as shown with reference to the rail and ties. Fig. 162B shows the curve of depression under another type of locomotive. This engine had no leading truck nor tender, but had a two-wheeled trailing truck. In the position it occupied during the test, the greatest depression of the rail occurred under the forward drivers, the rail presenting a sharp acclivity before the engine, and beyond the joint the contiguous rail rose slightly above the normal level. In the diagram, Fig. 162C, are shown the fiber stresses as measured on the base of the rail at station 14|, midway between ties Nos. 14 and 15. Advance wave determinations were made on the 66-pound rail on cinder ballast (8 inches under the tie) with the same class engine as shown in Fig. 162A, the engine weighing 125,000 pounds. With the locomotive slowly approaching, an upward movement of the rail began when the leading truck wheel was about 15 feet away ; the wave increased while the locomotive continued to advance, reaching a maximum of .0037 inch when the truck wheel was about 8| feet away. Then followed a sudden depression, and the height of the rail was reduced to the normal level when the truck wheel was about 1\ feet away. 222 STEEL RAILS The position of the locomotive when the upward motion of the wave first reached the station could be identified with considerable precision, but, owing to an appreciable interval of time being necessary for the level bubble of the TENDER 66000lbs. 30200ibs. 32600lbs r 287001bs. I8500lbs. NE AS SHOWN I N ' PC . . Q C)OQ ooo _Q 66lb.RAIL Same Track Stresses Lbs. ,..,, PER SQ.IN. AS A IN BASE COMPRESSION ASUREMENTS TAKEN ON A GAUGED LENGTH .OF 5 INCHES. ION I4>i (SEE A.) M AAA, A Fig. 162. — Railroad Track Experiments. C. B. & Q. R. R. measuring instrument to stop and reverse the direction of its movement, the position of the crest of the wave, as well as the time when the height of the rail was returned to its normal level, could not be so well defined. The wave length was probably somewhat less than the observations showed. The abruptness with which the direction of the wave motion was changed and STRESSES IN THE RAIL 223 ■* "" ^^^^i' i rO N —§— ?\ ^ i -T— CU ^ ^K H h- 6.4" _ H '' n _|_ __N__ ^K. s F— -- -A sr^ Fig. 163. — Advance Wave Determinations. (Cuenot.) the rail returned to its normal level, after which, of course, it was depressed below the normal, was a very striking feature of the observations.* * Fig. 163 shows the advance wave observed by M. Cuenot. It was found that when the first wheel of the engine is about 20 feet from a tie the upward movement commences and r mum at about 10 feet. 224 STEEL RAILS The observations of the depression of the roadbed made in these experi- ments are of importance. On cinder ballast that part of the roadbed in which the stakes were driven (31 inches from the track) was depressed a maximum of .049 inch and on gravel ballast the maximum was .036 inch. Wooden stakes and iron bolts were driven different depths into the roadbed with similar re- sults; in fact, the few observations which were made showed the longer stakes to have been quite as much depressed as the shorter ones, which did not penetrate the cinder ballast. Following out the depression of the roadbed in a lateral direction, on cinder ballast, when the middle driver of the engine was abreast the place of observation, there was a measurable depression at a distance of 91 inches from the rail. The recovery in the depression of the roadbed was not complete imme- diately upon the removal of the engine from that Fig. 164. — Movement of Rails Laid Alongside of Track. vicinity. The principal The right-hand rail lying by the near telegraph pole moved 40 feet, n^rt of the recovery at The trail it left may be traced from a point near the angle bar in the foreground. (Railroad Age Gazette, Dec. 17, 1909.) Once took place; the remaining portion of the depression, however, was very sluggish in returning. The length of time required to effect complete resilience was not determined. One observation, however, made nine minutes after the load was removed from the vicinity, showed the resilience then incomplete. STRESSES IN THE RAIL 225 Fig. 164 shows an exaggerated case of the wave motion and depression of the track. The road runs on an embankment about five feet above the level of a wet meadow. The wave motion of the track and embankment is so great that rails lying by the side of the track move along apparently of their own accord at the rate of nearly a foot a day. This movement was undoubtedly due to the undulatory movement of the track and entire fill and probably some reaction of the fill itself against the track. Further tests were made in 1894 and 1895 on the tracks of the Pennsylvania Railroad and the Boston and Albany by the Government. * These experiments comprise observations on the fiber stresses developed in rails in the track, the depression of the rails, and the slope or inclination of the rails caused by the weight of the different wheels of the locomotive. The results show some phe- nomena displayed by rails in service under the static conditions of loading or when a locomotive passes slowly over the track. The series were made chiefly on the track of the Pennsylvania Railroad, where exceptional opportunities existed for examining roadbed, embracing a wide variety of conditions of weight of rails and different kinds of ballast and its behavior under heavy types of freight and passenger locomotives. The tests were made during the early part of the month of November, 1894, on track in the condition it was found in service. The experiments on the Boston and Albany Railroad were made with track on frozen gravel ballast, in the month of February, 1895. The fiber stress tests were made by means of a micrometer mounted on the upper side of the flange of the base of the rail, at a place midway adjacent ties. The instrument covered a gauged length of 5 inches. The micrometer was adjusted in position, and then the several wheels of the locomotive were successively brought over the gauged length, or until the same was midway adjacent wheels. The instrument was read when the locomotive was at each of these posi- tions. It was found practicable to make the micrometer observations without arresting the locomotive in all cases, taking the readings as the locomotive passed slowly over the rail. In this manner the strains developed were measured, an elongation of the metal showing tensile stress, and a contraction in the gauged length showing compressive stress. The measured strains were reduced to stresses per square inch, assuming the modulus of elasticity of the steel to be 30,000,000 pounds per square inch, and correcting the observed strains in order to obtain the maximum fiber stresses, * House Documents, Vol. 46, 54th Congress, 1st Session, 1895-96. No. 54, Tests of Metals. 226 STEEL RAILS on the further assumption that the strains were proportional to their distance from the neutral axis of the rail. Fig. 165 shows the micrometer in position on the base of the rail, under the driving wheel of a locomotive. The depression of the rails was measured by means of a sensitive level bubble, mounted on a rod, carrying at one end a screw micrometer, which Fig. 165. — Railroad Track Experiments. View showing Micrometer for Measuring Strains in Rails, in Position on Base of Rail under Driving Wheel. rested on a stake driven in the roadbed 30 inches from the rail; the other end of the rod rested upon the base of the rail. The depression of the track was thus measured with reference to the top of the stake used as a bench mark. In this series it was necessary to arrest the movement of the locomotive at each observation. The slope tests, or inclination of the rails, were made by means of a sensitive level bubble mounted on a frame 12 inches long. At one end of the frame there STRESSES IN THE RAIL 227 was a fixed supporting rod having a conical point; at the other end there was a screw micrometer, the contact end of which was also made with a conical point. In the use of this instrument, two center punch marks, 12 inches apart, were made on the base of the rail. The conical points of the instrument entered these center punch marks and furnished definite contact points with the rail. The instrument was then leveled and the changes in slope, when the rail was affected by the locomotive, were measured from this initial adjustment of the level bubble. Fig. 165 shows the slope instrument resting on the second tie to the right of the fiber-stress micrometer. The rails examined ranged in weight from 60 to 100 pounds per yard, and were supported on oak ties resting on cinder, gravel, and stone ballast, in the case of the Pennsylvania Railroad. On the Boston and Albany Railroad, yellow pine ties, with shoulder tie plates, were used, the roadbed being ballasted with gravel, which was in a frozen condition at the time of the tests. TABLE LIV. — RAILROAD TRACK EXPERIMENTS. GENERAL DIMENSIONS OF RAILS GOVERNMENT RAIL TESTS (House Documents, Vol. 46, 54th Congress, 1st Session, 1895-96. No. 54, Tests of Metals) Weight Height, Width of Width of Tlnckne-.- Moment of Moment of Distance, Neutral Axis to per Yard. Base. Head. of Web. Inertia. Resistance. Outside Fiber. Pounds. Inches. Inches. Inches. Inch. / R=L. Headrc Inches. sk: 60 4i 41 2f i 14.222 6.693 2.125 2.125 70 4i 4| 2A 18.055 8.282 2.32 2.18 85 5 5 2& 1| 26.374 10.853 2.57 2.43 100 51 5h 2f! f 38.957 14.812 2.87 2.63 95 5* 51 3 I 32.28 13.563 2.65 2.38 The general dimensions of the rails are given in Table LIV. What was then considered a heavy type of freight and passenger locomotive was em- ployed, the weights of which are recorded in Table LV. Referring to the tests on the Pennsylvania Railroad, the tensile fiber stresses developed under the weight of the driving wheels ranged from 2810 to 19,540 pounds per square inch, and the compression stresses, when the gauged length was between wheels, reached 7880 pounds per square inch. These values belonged to the rails in their ordinary condition of service. A tie was removed from the track, laid with 100-pound rail, which increased the distance between centers of ties to 52 inches, and here the maximum tensile stress developed was 18,970 pounds per square inch, against 9840 pounds per square inch for another rail of the same section resting on ties 26 inches apart. 228 STEEL RAILS A splice bar on a 70-pound rail was strained 22,140 pounds per square inch, tension, and 8300 pounds per square inch, compression stress, by the driver of passenger engine No. 809. TABLE LV. — WEIGHTS OF LOCOMOTIVES GOVEE (House Documents, Vol. 46, 54th C NMENT RAIL TEST 3 6. No. 54, Tests of Metals) Locomotive. Total. En g ine. Tender. Weight per Wheel. Pilot. Drivers. Wheel. Pounds. Tons. Passenger No. 809, Class PK. Passenger No. 1515, Class T. Freight No. 557, Class R. Passenger No. 209, B. &A. R.R. Pounds. 197 050 222,500 188,600 199,700 39,750 50,300 11,000 40,700 Pounds. 87,300 95,200 800 75,000 Pounds. 70,000 77,000 63,800 84,000 Pilot 9,937 21,750 21,900 8,750 12,575 24,250 23,350 12,833 5,500 13,250 13,750 15,650 14,250 7,975 10,175 18,750 18,750 4.968 Driver, first. . . Driver, second. Tender Pilot Driver, first. . . Driver, second. Tender Pilot 10.875 10.950 4.375 6.287 12.125 11.675 6.416 2.750 Driver, first. . . Driver, second. Driver, third. . Driver, fourth.. Tender Pilot. . . 6.625 6.875 7.825 7.125 3.987 5 087 Driver, first. . . Driver, second. Tender 9.375 9.375 First truck. . . . Second truck. . . 9,250 11,750 4.625 5.875 Table LVI shows the maximum tensile fiber stress caused by the wheels of the pilot, engine, and tender on the different rails and kinds of ballast, also the maximum compression stresses developed in each experiment. The place of observation in these experiments was between ties and about one-quarter of the length of the rail from the end. From the irregular manner in which the stresses were developed in the different weights of rail, it is evident that the peculiar condition of the track at individual rails has an important influence on the magnitude of the fiber stresses. The lightest section of rail examined, 60 pounds per yard, resting on ties on gravel ballast, gave exceptionally low fiber stresses, and it will be seen that this rail was depressed a correspondingly small amount. So much variation is found in the stresses as to practically obscure the relative strength of the different weights of rails, and it seems necessary to compare the extreme sections to show a well-defined difference in the maximum stresses. STRESSES IN THE RAIL 229 On account of the peculiar conditions influencing the behavior of the individual rails, the relative values of the different kinds of ballast are less conspicuously shown in the fiber-stress experiments than in the series on the depression of the rails. TABLE L VI. — MAXIMUM FIBER STRESSES IN BASE OF RAIL GOVERNMENT RAIL TESTS (House Documents, Vol. 46, 54th Congress, 1st Session, 1895-96. No. 54, Tests of Metals) Tensile Fiber Stress per Square Inch. (Pounds.) Pilot. Drivers. Tender. 6,180 11,670 2,750 3,430 7,550 3,430 11,860 19,540 9,770 11,160 16,050 9,770 10,730 17,170 10,020 8,970 18,620 8,280 7,590 13,790 6,210 10,070 14,390 7,910 6,470 11,510 6,470 9,450 18,180 10,910 13,840 22,140 9,230 7,160 10,030 5,020 5,730 12,180 7,880 3,580 10,030 5,020 10,750 12,180 6,450 9,310 17,120 9,310 7,160 10,030 2,870 7,160 10,750 4,300 4,300 10,030 5,020 6,320 9,840 5,620 10,540 18,970 8,430 3,510 8,430 4,220 6,870 9.920 6,870 7,630 11,450 6,870 Passenger No. 809 Freight No. 557... Passenger No. 809 Freight No. 557... Passenger No. 809 Passenger No. 809 Freight No. 557. . . Passenger No. 809 Freight No. 557. . . Passenger No. 809. Passenger No. 809. Passenger No. 809.. Passenger No. 1515. Freight No. 557.... Passenger No. 809.. Passenger No. 1515. Freight No. 557. . Passenger No. 809 Freight No. 557... Passenger No. 809 Passenger No. 809 Freight No. 557.. . Passenger No. 209 Passenger No. 209 1,370 1,400 4,290 5,520 8,300 3,580 4,300 4,300 4,300 5.020 7,880 4,300 3,580 4,220 2,110 2,810 3,050 * Taken at different points on the rail. The relative effect of the several wheels of the locomotives are shown with greater precision than some other features of the test, inasmuch as in this comparison the action of all wheels are referred to the same point on the rail. Table LVII shows the tensile stresses developed per ton weight on the dif- ferent wheels of each locomotive on the several rails. From these results it appears that the stresses are generally greatest under the outside wheels. An examination of the results shows, as an extreme case, that the pilot wheels of freight engine No. 557 on a 60-pound rail, with stone ballast, gave a fiber stress of 4058 pounds per square inch per ton on the wheel, whereas the first driver of the engine, per ton, strained the rail only 1685 pounds per square inch. In this instance the total stress per square inch was the same under these two wheels, namely, 11,160 pounds, although the weight on the drivers was more than twice that on the pilot wheel. STEEL RAILS TABLE LVII. -TENSILE FIBER STRESSES IN BASES OF RAILS PER TON WEIGHT ON THE DIFFERENT WHEELS GOVERNMENT RAIL TESTS (House Documents, Vol. 46, 54th Congress, 1st Session, 1895-96. No. 54, Tests of Metals) PASSENGER LOCOMOTIVES Tensile Fiber Stress (in Pounds) per Ton Weight on Wheels of 95 D 95 L 95 B 95 D 95 H 95 K 95 L 95 M 95 N No. 809 No. 809 No. 1515 No. 809 No. 809 No. 809 No. 1515 No. 809 No. 809 No. 809 No. 809 No. 809 No. 809 No. 809 No. 209 No. 209 No. 209 No. 209 No. 209 No. 209 No. 209 No. 209 No. 209 Cinder Cinder Cinder Gravel Gravel Gravel Gravel Stone Stone Stone Stone Stone, tie removed .... Bridge Splice bar Frozen gravel, rail No. 1 Frozen gravel, rail No. 1 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 Frozen gravel, rail No. 2 1285 1927 2494 2110 1038 1038 519 FREIGHT LOCOMOTIVES Locomotive. Ballast. Tensile Fiber Stress (in Pounds) per Ton Weight on Wheels of Rail Weight per Yard. Pilot. Drivers. Tender. 1 2 3 4 1 2 3 4 85 60 No. 557 No. 557 No. 557 No. 557 No. 557 No. 557 No. 557 No. 557 Cinder 1302 1247 2760 2604 4058 2353 1564 1276 540 518 1250 974 1685 761 865 424 1041 999 1805 1146 2335 1046 1041 511 366 878 1323 824 1872 1011 732 718 1408 1060 2512 1408 2056 1615 1408 1183 860 1558 720 2450 1264 1078 705 898 617 1384 720 1926 1084 898 880 720 860 1038 359 2275 903 898 351 1259 860 70 1384 85 60 Gravel 720 2450 70 85 100 Stone Stone Stone .. 1623 1259 1058 STRESSES IN THE RAIL 231 Throughout this and earlier series of track experiments the same tendency- has been found, the outside wheels exerting the most severe action on the rails in proportion to the weight which they carry. The maximum and minimum tensile stresses per ton on the different wheels are shown in Table LVIII. TABLE LVIII. ■ MAXIMUM AND MINIMUM TENSILE STRESSES PER TON ON THE DIFFERENT WHEELS GOVERNMENT RAIL TESTS ■use Documents, Vol. 46, 54th Congress, 1st Ses -96. No. 54, Tests of Metals) Maximum Stress. Gravel . Gravel . Stone . . . Stone . . . Cinder.. Gravel . Gravel . Stone . . . Stone Bridge Splice bar. Cinder..... Cinder.. Cinder. . Gravel . Gravel. . Gravel . Stone... No. 8 Freight No. 557 Passenger No. 8 Freight No. 557 Passenger No. 809. Passenger No. 8 Freight No. 557 No. 8 Stone ! Stone | Stone, tie removed Stone Gravel, frozen* . Gravel, frozen* . Gravel, frozenf . Gravel, frozenf . Gravel, frozenf . Gravel, frozenf . Gravel, frozenf . Gravel, frozenf . Gravel, frozenf . Freight No. 557 Passenger No. 809. Passenger No. 809, Passenger No. Passenger No. 1515. Freight No. 557. Passenger No. 8 Passenger No. 1515 Freight No. 557.. . Passenger No. 809. Freight No. 557. . . Passenger No. 809. Passenger No. 809. Freight No. 557. . . Passenger No. 209. Passenger No. 209. No. 209. No. 209. Passenger No. 209. Passenger No. 209. Passenger No. 209. Passenger No. 209. Passenger No. 209. 1st pilot. . Pilot Pilot Pilot 4th tender . 4th tender. Pilot 1st pilot. . Pilot 4th tender . 1st pilot. . 1st pilot. . 1st tender. 4th driver. 1st pilot . . 1st pilot. . Pilot 1st pilot. . Pilot... 1st pilot 1st pilot Pilot... 1st pilot 1st pilot 1st pilot , 2nd tender 1st pilot. . 1st pilot. . . 1st pilot . . . 1st pilot. . . 1st pilot. . . Pounds. 1244 1247 2387 4058 2290 2353 2494 2789 1441 1228 1408 2164 1481 2604 1441 1564 1272 2122 1276 1199 1351 1500 1485 1500 1500 1st tender... 1st driver. .. 3rd tender. . 1st driver... 2nd driver. . 1st tender. . 3rd tender . . 1st, 2nd, 3rd tender 1st driver. 2nd driver . 2nd tender. . 2nd, 3rd tender 2nd pilot . . . 1st driver... 2nd pilot. . . . 1st tender. . 3rd tender . . 2nd, 3rd tender 3rd driver 2nd pilot.. 3rd driver 3rd driver 1st driver. 1st tender. 3rd, 4th tender 1st driver. 1st driver. 1st driver. 2nd, 3rd tender 2nd tender 2nd tender 471 518 1595 1285 451 733 -164 Illustrative of the influence which the condition of the roadbed has on the fiber stresses, the 60-pound rail on gravel ballast showed 1247 pounds per square inch stress per ton under the pilot wheel of the engine, whereas, 232 STEEL RAILS with the same weight of rail on stone ballast, the same wheel gave 4058 pounds per square inch. The fiber stress experiments on the Boston and Albany Railroad were made on rails 95 pounds per yard, on frozen gravel ballast, and observations were taken at several points along the length of the rails. The observations on rail No. 1 were made with the rail in the condition in which it was found in the track. There was some looseness between the tie plates and the rail and ties, which, in rail No. 2, was diminished as far as possible by redriving the spikes and by the use of a number of additional ones. This is the only instance in which spikes were redriven before testing. Rail No. 1 was examined at two, and No. 2 was examined at seven, places along its length. The tensile fiber stresses at the first end of rail No. 2 were higher than those developed at the middle and near the second end of the rail. In this rail, as the tensile stresses diminished at the second end, the compressive stresses increased. At a space 33 inches from the end of the rail, the compressive stress in the base reached 7630 pounds per square inch when this space was midway the drivers. The same stress was also shown when the space was between the tender trucks. Concerning the relation between the fiber stress developed and the total depression of the rail, the evidence generally favors the deduction that di- minished depression will be accompanied by diminished fiber stress. The depression of the rails examined on the Pennsylvania Railroad shows, with the 60-pound rails, the least depression on the gravel ballast, the order of rigidity being gravel, stone, and cinder ballast. With the 70-pound sections, the order of rigidity is gravel, cinder, and stone ballast. Under the 85-pound rails, the stone ballast gave greater rigidity than the gravel. No test for de- pression was made with cinder ballast under the 85-pound rails, and only stone ballast was used under the 100-pound rails. Table LIX states the mean depression of the driving wheels, and also the mean depression of all the other wheels of the locomotive in each experi- ment. There is in the table a column of differences which states the excess of depression of the drivers over that of the other wheels. The column of differences is useful in showing the additional depression of the rails under the weights of the driving wheels after they have been loaded by the other wheels. Under the 60- and 70-pound sections, the gravel ballast gave the greatest rigidity under the drivers, as well as under the other wheels, and in the column of differences the excess of depression was least for this kind of ballast. STRESSES IN THE RAIL 233 The total depression with 85-pound rails was less for the stone than for the gravel ballast, although the excess of depression under the drivers was practically the same in the two cases. The depression of the rails on frozen gravel ballast, in which there was no visible movement of the ties, would seem to represent about the attainable limit of rigidity in track on wooden ties. The fact that 60-pound rail on gravel compares favorably with the heavier section on the frozen ballast indicates that this light section of rail was in a condition approaching rigidity. In the slope tests, the approach of the locomotive was felt for a distance of 12 to 15 feet in front of the first wheel. The first observed movement was TABLE LIX. — DEPRESSION OF RAILS — MEAN DEPRESSION UNDER DRIVING WHEELS AND MEAN DEPRESSION UNDER PILOT AND TENDER WHEELS GOVERNMENT RAIL TESTS (House Documents, Vol. 46, 54th Congress, 1st Sess'on, 1805-96. No. 54, Tests of Metals) Rail Weight per Yard. Ballast. Locomotive. Drivers. Pilot and Tender. Difference. Pounds. 60 Cinder .229 .073 .162 .230 .138 Inch. .154 .042 .122 .157 .089 .075 60 .031 60 Stone .040 70 .073 70 .049 70 Stone .277 | .207 .233 .184 .070 85 .049 85 Stone .144 .168 .139 .097 .116 .103 .047 100 .052 95 Gravel, frozen, rail No. 1 Passenger No. 209 .036 an upward one, the inclination of the rail sloping in a direction from the loco- motive. This was followed by a reversal in the direction of the inclination, which then sloped toward the locomotive. As the several wheels successively passed over the place of observation, the inclination of the slope reached a maximum and was reversed in direction, these motions being repeated under each wheel with some modifications, according to the condition of the track. After the locomotive had passed over the place of observation the inclination gradually diminished, and eventually the rail practically resumed its original level. A very critical examination led to the conclusion that each passage of a locomotive left the rail in a slightly different state than it before occupied, and that some sluggishness of recovery in the ballast had an influence on these minute displacements. 234 STEEL RAILS Figs. 166 and 167 show graphically the results of the tests for depression and stress in different kinds of ballast and weights of rails. r 1 ' r! ~ v ' fen ■ 'Q'- 4 34" w 5-7 " ■w 4 -"- | A.< 5 '- 7 '" >. @ i (T 0.26" D U 0.28" CO < -J Lu O.JO'/' II T > D LU Q. O _l co to CD LU > z* .oooo 01 D O in 00 o vl 1- Z UJ K) UJ Z o z to to > a. to <0 aoooc >UB5.- s i:_J_L o Ul O i CO 2 CO STRESSES IN THE RAIL 243 The construction of Fig. 171 is similar to that of Plate XXIII. The scale to which the elastic curve is drawn is, 0.002 inch equals one space vertically, and 2 inches equals one space horizontally. In deriving the slope curve, the actual ordinates of the elastic curve are measured in fiftieths of an inch, and one vertical space on the slope curve is taken to represent one-fiftieth of an inch of the elastic curve ordinate. The base is taken in all the curves as two spaces. The value of one vertical space of the slope curve is, then, 2 1 1 1 1000*50' (&=*&) "2' 2 j. 50 1 1000*50' 10 *2* 2 _1 1 1 1000*10*2 10,000* For example, the ordinate of the elastic curve at 2 inches to the right of the ?el is about — inch; the actual slope is, therefore, tan = p. -r- ^ or — -=- — = .5, 5U 50 10 50 50 as shown by the slope curve between and 2 inches. The ordinate of the elast 7.5 wheel is about — inch; the actual slope is, therefore, tan = p. -r- ^or— -=- — = .5, 50 50 10 50 50 itween 12 5 elastic curve at 4 inches is about -=_- or the rise from 2 inches to 4 inches is 50 rA - and the slope .75, as appears on the slope curve, between 2 inches and 4 50 inches. The ordinates on the moment curve are taken the same number of spaces as the corresponding breaks in the curve of slopes and consequently, on account of the base being 2 spaces, represent twice the actual slope of the slope curve. The value of one vertical space in the moment curve is, then, 1 1 1 FT 10,000 2 2 — [— ■ \>\ • 30,000,000 x 43.8 = 32,850 inch-pounds. The ordinates of the shear curve are five times those of the moment curve, and the value of one vertical space in the shear curve is 32,850-|-|-| = 1643 pounds. The most simple way to construct the diagram is to approximate the elastic curve of the rail and then follow out the operations, as shown by Table LX, correcting the elastic curve from column 11 of the table and readjusting the calculations, if necessary, to the corrected elastic curve values. 244 STEEL RAILS TABLE LX. — CALCULATIONS OF RAIL DIAGRAMS FOR 60-INCH WHEEL SPACING Horizontal Depression track- 2 Pounds. Shear. Moment. Slope. Elastic curve Pounds. Spaces. 5 2Xtan. 6 Ordinate. 2Xtan. Ordinate. 9 2Xtan. 10 Ordi- 11 0.30 "2800 " 20,080 12.2 2.44 6.1 4.9 2 4.9 2.5 4 17,280 10.5 2.10 4.9 4.9 6 2760 2.8 2.8 7.4 8 14,520 8.8 1.76 7.7 7.7 10 2720 1.0 1.0 15.1 12 11,800 7.2 1.44 8.7 8.7 14 2680 - .4 - .4 23.8 16 0.29 9,120 5.6 1.12 8.3 8.3 18 2640 -1.5 -1.5 32.1 20 6,480 3.9 .78 6.8 6.8 22 2610 -2.3 -2.3 38.9 24 3,870 2.4 .48 4.5 4.5 26 2590 -2.9 -2.9 43.4 28 0.28i 1,280 8 .16 1.6 1.6 30 1280 -3.1 -3.1 45.0 Note. — Col. 3 is found from col. 2 and Fig. 142. Col. 4 is found from col. 3 and is I be total load rained from the center of the span. Col. 5 is found from col. 4 by dividing the figures given in col. 4 by 1643. Col. 6 is found from col. 5 by dividing the figures given in col. 5 by 5. In Fig. 172 are given diagrams for spans of 70 inches, 80 inches, and 90 inches between centers of drivers. The maximum bending moment can be read directly from the moment curve and the wheel load is twice the load supported on half the span or twice the total reaction shown by the shear curve of the diagrams. In comparing the shear curve with the curve of pressures of the ties it would seem desirable to assume the rail to be supported by a distributed load in place of a series of loads concentrated at the ties, the effect will be practically the same and the calcula- tions much simplified. The results of static and dynamic tests of the stress in the rail both indi- cate that the negative bending moment between the drivers is very much smaller than the positive bending moment produced in the rail under the drivers. The dynamic tests appear to show a ratio of about 1 to 4 or a compressive stress in the base of the rail only one-fourth as great as the tensile stress, under normal conditions. In poorly tamped track the compression stress seems to increase. If the rail were uniformly supported between the wheels the compression stress would be one-half the tension stress under the wheels of a set of drivers. Such a condition of the pressure exerted by the tie would be represented by a horizontal line in Fig. 142. The diagrams given in Figs. 171 and 172 show that, as the spacing of the drivers increases, the negative bending moment or the compression stress in the base of the rail decreases in relation to the tension STRESSES IN THE RAIL 245 WHEEL TO" CJOC WHEEL 3 80" CJOC wheel: 90- CioC /■ / / / / > / / O / / y o / / In < ^)^o / / y r \ UJ > ^N s / \ a. D O / \ \ / \ uJ / \ \ / \ g sooo \ oooo \ 3IN.LBS \ r? \ \ \ s \ i- z O 2aocx LBS \ 240CX )LBS \ 220CX > u 1 to Fig. 172. — Rail Diagram for Wheel Spacing of 70, 80, and 90 inches, one-half size of original diagram. 246 STEEL RAILS stress; for drivers spaced 60 inches apart it is practically one-half the tensile stress, but when the spacing is increased to 90 inches it is not much more than one- third. An examination of Fig. 142 makes this clear and shows that with the greater deflection obtained in the 90-inch span the ties in the center of the span support relatively much less of the load. With lighter rail the deflection would be still further increased and a greater ratio of the tension to the compression stress obtained. The full line, shown in Fig. 170, shows the true allowable wheel loads given by the diagrams of Figs. 171 and 172. Up to spans of 80 inches the wheel load is limited by the safe bearing power of the tie and is obviously less than that obtained from the assumption that there is a uniform distribution of the wheel pressure to the ties upon which the dotted line of Fig. 170 is based. After the spacing of the drivers exceeds 80 inches the wheel load is limited by the bending moment in the rail; here the bending moment is greater for a uniformly dis- tributed load and, consequently, the dotted line in the figure falls below the full line. Turning our attention to the allowable wheel load as determined by the conditions at the front and rear drivers. Figs. 162 and 163 show that there is a wave motion of the rail ahead of the engine and the rail rises slightly above the trackman's surface. This lack of pressure on the rail at the outside wheels causes these wheels to exert a more severe action on the rail. This is clearly shown by Table LVIII and in Fig. 162, where the outside drivers, although carrying less weight, gave practically the same stress as the middle driver. Records Nos. 2 and 3 of Fig. 169 illustrate the same tendency. The rail diagrams, just worked out, show that in increasing the wheel spacing from 80 to 90 inches the permissible wheel load fell from 24 to 22 tons. From the diagram for the 90-inch wheel spacing it is seen that the ties in the middle of the span afford little support, and while it is somewhat problematic what load will be carried by the rail ahead of the front driver, we will not be very far wrong if we assume it to carry 8 tons with no leading truck, 9 tons with a two-wheel leading truck, and 10 tons with a four-wheel leading truck. On account of the load of the tender wheels and the effect of the draw- bar pull, we may reasonably take 10 tons where a trailing truck is used and 9 tons where there is no trailer, as the load carried by the rail back of the rear drivers. Table LXI may now be prepared showing the allowable dynamic wheel load under different conditions of wheel spacing. STRESSES IN THE RAIL TABLE LXI.— ALLOWABLE DYNAMIC WHEEL LOAD (POUNDS) FOR 100-POUND A. S. C. E. RAIL Middle wheel Front wheel, No leading truck Two-wheel leading truck. . Four-wheel leading truck. . Back wheel, No trailing truck Trailing truck 36,000 38,000 40,000 38,000 40,000 42,000 40,000 42,000 Inches. 90 Inches 40,000 42,000 44,000 38,000 40,000 42,000 Referring to Figs. 31 and 32, of typical load diagrams of engines, it will be seen that with the exception of the articulated engine there is had a very satis- factory agreement between Table LXI and the diagrams. We have now to consider the stresses in the rail caused by the bending moment and shear derived in Figs. 171 and 172. The maximum bending moment in these figures is 300,000 inch-pounds, and the maximum shear is 24,000 pounds. It is beyond the scope of the present work to enter into the discussion of mathematical investigations of continuous web strains, and in order to form some conception of the nature of stresses in the continuous rail we shall view the matter in the simplest manner possible.* In the rail under the wheel it is evident that, by virtue of the bending stress, that part of the rail above the neutral axis is subject to compression, and that below to tension, both of which stresses attain maximum values at the outermost fibers of the rail, and decrease to zero at the neutral axis. This intensity of the stress at any point is at once obtained from the well-known equation of flexure: M ~y = f, (a) where M is the bending moment, I the moment of inertia of the section of the rail, y the distance of the point from the neutral axis, and / the intensity of the stress at that point. Table LXII gives the extreme fiber stress in the base due to bending in different sections of 100-pound rail, caused by a bending moment of 300,000 inch-pounds. The high moment of inertia in the Series "A" of the American Railway Association would giVe a slightly different elastic curve for this rail than is shown for the A. S. C. E. section in Figs. 171 and 172, with the result * See Plate Girder Construction, Isami Hiroi, New York. 248 STEEL RAILS that the bending moment would be increased and the unit of load supporting the rail decreased. TABLE LXIL— EXTREME FIBER STRESS DUE TO A BENDING MOMENT OF 300,000 INCH-POUNDS Section. Weight. Extreme Fiber A. S. C. E Am. Ry. Assn., Series "A" Am. Ry. Assn., Series "B" Pounds per Yard. 100 100 100 Pounds per 18,600 16,900 19,100 Fig. 173. — Distribution of Horizontal Stress in Rail. The bending moment M decreases as we proceed toward the center of the space between the wheels, and with it evidently the intensity / of the hori- zontal stress also; so that / varies not only in vertical directions on both sides of the neutral axis, but also in the direction of the length of the rail. x , Let xx and x'x', in Fig. 173, be r\ "\" "P* two sections of a rail, very close to each other, and NN the neutral axis. The variation of the value of / in both sections may be represented by triangles with apices in the neutral axis, and the variation in the longitudinal direction between these two sections by the difference of the areas of two triangles, as shown shaded in the figure. This increase of horizontal stress from one section to another produces at each longitudinal layer a force tending to slide it past the layer next above it, and is transmitted undiminished toward the neutral axis, where this shearing force, which has been increasing at every layer, attains its maximum intensity. This stress is called the longitudinal shear, and can be at once obtained from equation (a). Thus, let /' be the corresponding value of / in section x'x'; and let M and M' be the bending moment in the two sections xx and x'x' re- spectively, and a an infinitely small cross area, distant y from the neutral axis. The total horizontal stresses acting in that part of the section lying between the extreme fiber distant h from the neutral axis and the layer y'y' distant y' from the axis in xx and x'x' are respectively: 2>> %f'a. STRESSES IN THE RAIL 249 The longitudinal shear in the layer y'y' between the two sections is, there- fore, equal to h h %fa - %fa. 1/ 2/' Substituting in the expression the values of / and /' given by equation (a), we obtain, ± f , 4w M' - M v Zii a- Z,f a= f — Z, ya - y' y' 1 2/ Since the area on which this horizontal shear is acting is equal to b Ax, when b is the breadth of the cross section at the layer y'y' and Ax the distance between x and x', we obtain for the intensity of the shear, -Jb^-^- (b) Thus at every point in the rail there are two shearing actions taking place at the same time, one the longitudinal shear and the other the vertical shear. Imagine abed, Fig. 174, to be an infinitely small a ^-^ x - h - ^ portion of the side of a rail at a point distant y' ^ ^ x from the neutral axis. Suppose the side of this J* ^ ^y *•' area element to be Ax and Ay, and the breadth of the J' J -j -J-' beam at the point to be b. There are then found two FlG _ 174. —shearing stress of Point shearing stresses on this element, one vertical and Distant y' from Neutral Axis, the other horizontal. These two shears form two pairs of couples acting around the body, as shown by the arrows. Let t x represent the intensity of the horizontal shear at this point and t y that of the vertical. The amount of the horizontal shear is equal to t x Ax b; that of the vertical shear is likewise equal to t y Ayb. In order that the body be in equilibrium, the moment of these couples must be equal, i.e., t x ax b Ay = t y Ay b ax. Consequently, t x = t y (which is always the case), showing that at every point in the rail the intensities of the vertical and horizontal shears are equal, and we will hereafter designate them with the common letter t. The value of t x has already been deduced in equation (b), namely: , M ' - M ^ . . - M — = S z , where S x is the total vertical shear at the sec- jaX Substituting this value of — in equation (c) , there results: t = fj%ay, (d) 250 STEEL RAILS or the intensity of the shearing stress at any point in the rail is equal to the total shearing force on the entire cross section multiplied by the statical moment of the area of the section outside the longitudinal plane of shear in question about its axis in the neutral plane, divided by the product of the moment of inertia of the entire section into the breadth of the section at that point. Fig. 175 shows the intensity of the shearing stress in a 100-pound rail, the total vertical shear at the section being 24,000 pounds. Fig. 175. — Shearing Stress in 100-pound A. S. C. E. Rail. There still remains to be considered the horizontal force /, whose value is given in equation (a), tending either to compress together or pull asunder the two faces ac and bd (Fig. 174), according as it is on the upper or lower side of the neutral axis. At the neutral axis where / = 0, t x and t y are then the only stresses, and we know from mechanics that the resultant action of two equal shears at right angles to each other, exactly as t x and t y are, is equivalent to that of two equal and opposite stresses at right angles to each other, called the principal stresses and making an angle of 45° with the shearing stresses. But at a distance each STRESSES IN THE RAIL 251 side of the neutral axis the third stress, /, now comes in, which evidently gives a new direction to the line of resultant stress, turning the axis of principal stresses toward itself more and more as its intensity increases. Fig. 176 represents the appearance which the lines of principal stresses thus obtained present in a beam loaded in the middle and supported at each end. The lines of maximum tension are shown dotted and cut the lines of compression always at right angles. Both lines cross the neutral axis at an inclination of 45° and run almost parallel to it in the middle of the beam in the neighborhood of extreme fibers. Fig. 176. — Lines of Principal Sti Now comes the question how the web should be proportioned to resist such stresses : The greatest intensity of the vertical shearing stress on the verti- cal section of the rail, shown in Fig. 175, is about* 10,000 pounds per square inch. In modern bridge practice a shearing stress is allowed in web plates of 10,000 pounds per square inch, which gives a satisfactory thickness of the web for the rail shown in the figure. But as has already been explained, the action of the shearing stresses at the neutral axis is equivalent to compression and tension at right angles to each other and of equal intensity, making an angle of 45° with the axis, and the web is still in danger of failing by flexure under this com- pression stress. Consequently, the web with its thickness as already proportioned for shearing must now be examined for its strength as a column. We will probably be not far from correct if the length of the column is taken as h sec 45°, h being the vertical distance between the top of the flange and bottom of the head of the rail. Then, for the 100-pound A. S. C. E. rail, h sec 45° equals 4.4 inches, and the load is = p = 10,000 pounds per square inch. This amount is correct for the bending stress caused by the load which is central over the rail head. The wheel load is, however, rarely applied exactly in line with the vertical axis of the rail, and the additional couple due to the eccentricity causes a torsion in the rail. To make a correct analysis would 252 STEEL RAILS be very complicated and decidedly uncertain on account of the lack of experi- mental evidence. No column formula can be made to apply exactly to the web of the rail. If we apply the formula for a column with an eccentric loading of .6 of an inch, the resulting stress amounts to over 50,000 pounds per square inch. It is doubtful, however, whether the stress introduced by this torsion can be com- bined with those due to bending in this manner. It will be observed that, even were this large stress correct, there is a tensile stress acting at right angles to the compression stress and tending to hold the strip in its true plane. Just what the restraining influence of this tensile stress is cannot be determined theoretically, but the following experi- ments show it to be of importance. During 1910 tests were made at the Maryland Steel Company's plant at Sparrows Point, Md., for the purpose of determining what effect the eccentric loading of the wheel had on the head and web of the rail.* The tests Were made with a 200,000-pound test machine by canting a piece of rail 18 inches long and applying the load at the edge by means of a block with a radius of 16^ inches, to represent a car wheel, where it came in contact with the rail. Other tests were made with a reciprocating machine representing a loaded wheel rolling back and forth on the edge of the canted rail. For the tests a rail was taken from stock and six pieces each 18 inches long were cut from it for test in the stationary test machine and six similar pieces were used for test in the reciprocating machine. In order to have the material as uniform as possible throughout the section and in the different pieces, a " C " rail was selected, that is, the third rail from the top of the rail bar. The rail was a 90-pound A. R. A. type B section and the pieces were planed down to thicknesses of head at the side of | inch, \ inch, f inch, § inch, | inch, and 1 inch, two pieces of each thickness, one for each kind of test. In each case the brand side of the head of the rail, which was the bottom side as rolled, was planed vertical to a width of li 3 g inches from the center line. Fig. 177 shows the dimensions of the section used and also gives diagrams of the pieces tested. The essential dimensions of the head of the pieces tested, as indicated by letters A, B, and C, on Fig. 177, measured as shown in Table LXIII. Two samples were taken with a |-inch drill for analysis from a section near the middle of the length of the rail, one close to the upper corner and the other at the junction of the head and the web. The results of the analyses are shown in Table LXIV. * Strength of Rail Head, M. W. Wickhorst, Proceedings Am. Ry. Eng. & M. of W. Assn., 1911, Vol. 12, Part 2, p. 518. STRESSES IN THE RAIL 253 These results show the material to be very uniform. TABLE LXIII. — DIMENSIONS OF HEADS AS TESTED FOR STRENGTH OF RAIL HEAD Test Numbers. Thickness of Head. Width. Edge, Center, B. Side to Center, C. 1.02 91 .76 .62 .51 .38 1.23 1 15 1.02 .86 .75 .64 1.15 1.18 1.17 1.15 1.16 1.17 3 and 4 5 and 6 7 and 8 11 and 12 TABLE LXIV. — ANALYSES FOR STRENGTH OF OF RAILS TESTED RAIL HEAD Corner of Head. Junction of Head and Web. .538 .523 .070 .055 .81 .103 .18 None Phosphorus 070 050 81 103 19 N"one Silicon Copper Nickel Chromium Tensile tests were also made of pieces cut from near the middle of the rail, two pieces |-inch diameter and 2-inch gauge length, for longitudinal test from the center of the head, and two pieces |-inch diameter and 1-inch gauge length for transverse test across the center of the head. The yield point in the 2-inch pieces was determined by means of a Capp's multiplying dividers. The results of the tests are shown in Table LXV. TABLE LXV. — TENSILE TESTS OF RAILS TESTED FOR STRENGTH OF RAIL HEAD Yield Point (Pounds per Tensile Strength (Pounds per Square Inch). Elongation. Eeduction of Longitudinal a 2-inch gauge length b Average Transverse a 1-inch gauge length b Average 51,000 52,700 51,850 111,600 111,500 111,550 110,200 111,200 110,700 16 16.5 16.3 6 7 6.5 29 29 29 7 9 8 These results show material of good ductility longitudinally and the stretch crosswise of the head shows up well for a transverse test. STEEL RAILS - Diagram of Pieces tested for Sag of Rail Head and I (Am. Ry. Eng. Assn.) «. 4':^ 4" CT^sJ : — — ^° — 18" - — — — -— i -_-^__^ ,. -^ -1 L 1 Fig. 178. — Method of Stationary Tests for Sag of Rail Head and Bending of Web. (Am. Ry. Eng. Assn.) The arrangement used for making the stationary tests is shown in Fig. 178, and is intended to represent a 33-inch car wheel resting on the edge of the top of the rail. The head is thus tested as a cantilever, the load tending to sag the head locally and to also bend the web. STRESSES IN THE RAIL 255 The load was applied in increments of 10,000 pounds up to 60,000 pounds and then in increments of 20,000 pounds up to 200,000 pounds, the capacity of the test machine. The sag of the head was determined by measuring the distance by means of dividers, between prick-punch marks placed on the side of the head near the bottom and on the base, as indicated in Fig. 178, the load being on while taking the reading. The marks on the base were placed about one inch from the web, by gouging some of the metal so as to have a vertical surface on which to prick-punch the mark. The amount that the opposite side of the head elevated, or the " lift," was determined in a similar manner. The results of these tests are shown in Table LXVI. TABLE LXVI. -STATIONARY TESTS IN TEST MACHINE OF STRENGTH OF RAIL HEAD Sag and Lift in Inches w i -inch Head. 3-inch Head. f-inch Head. 1-inch Head. |-inch Head. 1-inch Head. Sag. Lift. Sag. Lift. Sag. Lift. Sag. Lift. Sag. Lift. Sag. Lift. 10,000 .00 .02 .05 .06 .08 .09 .00 .00 .00 .01 .01 .02 .00 .01 .02 .03 .04 .05 .06 .07 .08 .09 .10 .11 .13 .00 .00 .01 .01 .01 .02 .02 .02 .02 .02 .02 .02 .02 .00 .00 .00 .00 .00 .01 .01 .02 .03 .03 .03 .04 .04 .04 .00 .01 .01 .01 .02 .02 .02 .03 .03 .03 .03 .03 .03 .03 .00 .00 .01 .02 .02 .03 .04 .04 .05 .05 .06 .07 .08 00 20,000 01 02 04 06 07 10 11 12 13 14 15 16 00 01 01 02 03 04 05 07 OS os 09 10 01 01 02 03 04 05 06 07 OS 08 09 in .02 .02 .02 .03 .03 .04 .04 .04 .04 .04 .04 .03 30,000 40,000 .... .00 50,000 01 60,000 02 80,000 .02 100,000 02 120,000 .03 140,000 .15 .17 .20 .03 .03 .05 03 160,000 .03 180,000 03 200,000 .02 These results are plotted in Fig. 179, in which the load is plotted against the sag of head for each thick- ness of head tested. The f-inch head, according to these curves, gave a greater sag than £h e --inch head. •^ IG - 1 ^- — ^ag °f *t au Head in Stationary Tests. (Am. Ry. Eng. Assn.) Although this is according to the measurements obtained, it would seem to be in error, due, perhaps, partly to errors of measurement, but probably also 256 STEEL RAILS due to some condition which cannot be accounted for, as, for instance, application of the load. The curves show that a load of 10,000 pounds does not sag the head with the load applied to the edge of the top side, with any thickness down to f inch, and probably neither does a load of 20,000 pounds, although, as the load was on when the measurement was taken, we cannot say how much of the sag was elastic and how much permanent. A load of 30,000 pounds seems to cause a permanent sag with the f-inch head, but not much, if any, with the heads of greater thickness. It is interesting to note in this connection that the web seemed to stand the load of 200,000 pounds successfully. Tests were also made with the reciprocating machine, shown in Fig. 151, in which a piece of rail is moved back and forth under a wheel to which a load can be applied by means of a system of levers. The rail is fastened to a steel bloom which runs on rollers running on another steel bloom that forms the bed of the machine. The rail bed is connected by means of a connecting rod to the bed plate of a planer, which furnished the power to run the rail machine. The weights attached to the weight hanger are multiplied 600 times as applied to the axle of the wheel, and in these tests weights of 50, 100, and 150 pounds were used, so that the wheel loads were 30,000, 60,000, and 90,000 pounds re- spectively. A piece of rail 18 inches long was tilted on an inclined plane of 1 in 10, as in the other tests, and the wheel, loaded with 30,000 pounds, was run back and forth over a length of about 10 inches for 100 double strokes, which made 200 movements of the loaded wheel over the rail. The sag of the head and the width of the bearing taken by the wheel were then measured with no load; the load was then increased to 60,000 pounds and the wheel again run on the rail as before. The measurements were again taken and a final test made with a load of 90,000 pounds. The results of these tests proved to be interesting and fairly definite, and are shown in Table LXVII. TABLE LXVII. — RESULTS OF ROLLING TESTS OF STRENGTH OF RAIL HEAD Thickness of Head. Sag of Head. Inches. Width of Bearing. Inches. 30,000 Pounds. 60,000 Pounds. 90,000 Pounds. 30,000 Pounds. 60,000 Pounds. Si ^ inch .05 .01 .00 .00 .00 .00 .13 .08 .05 .03 .01 .00 .17 .13 .13 .10 .08 .05 .56 .34 .31 .32 .32 .23 1.20 1.00 .76 .70 .58 .60 1.56 1.42 1.40 1.28 1.16 1.00 1 jj^h 1 - mc h 3 jjjgjj | inch STRESSES IN THE RAIL 257 The results showing the relation of thickness of head and sag of head under loads of 30,000, 60,000, and 90,000 pounds are plotted in Fig. 180. It will be noted that 30,000 pounds produces no sag when the head is f inch or over in thick- ness. With 60,000 pounds the head must be 1 inch or over in thickness. All the samples tested sagged under 90,000 pounds, but by extending /the curve it seems probable that a head If inches thick would hold up a rolling load of 90,000 pounds when con- centrated at the edge. < Ul U. £.05 V ROLLING TESTS s ^S^ 90,ooo LBS. S^ ^ -60,000 LBS. 30,ooo LBS. %" l/ 2 " 5/ 8 " %" 7/ e " ,•• THICKNESS of HEAD - Sag of Rail Head in Rolling Tests. (Am. Ry. Eng. Assn.) After the rails were tested they were cut in two and their sections are shown in comparison with the original rail section in Fig. 181. The rolling load of 90,000 pounds applied at the edge of the head pro- duced very little or no bending of the web with the section used, which was a 90-pound A. R. A. type B, with a thickness of about -^ inch at the middle. While there seems little liability of the web failing as a column, the height of the rail in reference to the stability of the outer rail on curves must be considered. * Mr. E. E. Stetson found that in many cases the resultant of the hori- zontal force and wheel pressure on curves falls entirely outside the base of the rail in the 100-pound section. In 1907 the Pennsylvania Railroad Company prepared a piece of track on the West Jersey and Seashore Railroad, on a 1-degree curve, near Franklin- ville, N. J., with special cast-steel ties and measuring apparatus, for the pur- pose of comparing the effects of lateral horizontal forces on the outer rail of the curve generated by different classes of electric locomotives and standard steam locomotives. The force exerted by the locomotive was communicated to steel plates by means of hardened steel spheres of small diameter, and the effect of the force * A Study of Rail Pressures and Stresses in Track Produced by Different Types of Steam Loco- motives when Rounding Various Degree Curves at Different Speeds. E. E. Stetson, Proceedings Am. Ry. Eng'. & M. of W. Assn., 1909, Vol. 10, Part 2, p. 1432. 258 STEEL RAILS was to cause the spheres to make a more or less deep impression in the steel By means of laboratory tests, it was determined what forces in pounds were required to produce various known depths of the impression of the steel balls in the plates, and after this calibration had been made it was possible to transform the depths of the impressions of the balls in the plates into pounds Fig. 181. — Rails after Rolling Test with Load of 90,000 Pounds. (Am. Ry. Eng. Assn.) of pressure. Table LXVIII-A gives the results of some of these tests for steam locomotives, in order that they may be compared with the computations made by Mr. Stetson, which are shown in Table LXVIII-B for the same degree of curve and for one locomotive of the same class as used in the tests on the Atlantic City line. Mr. Stetson's calculations are for speeds of 60 miles per hour, which are from twenty to thirty miles per hour less than the actual tests, but the weights of the locomotives are heavier. The lower speeds should give smaller pressures, while, on the other hand, the heavier locomotives should give higher pressures. STRESSES IN THE RAIL 259 TABLE LXVIII. - HORIZONTAL PRESSURES EXERTED BY STEAM LOCO- MOTIVES AGAINST RAIL ON CURVES (Am. Ry. Eng. Assn.) Run Number. Speed in Miles Speed Corre- Superelevation. Type of Loco- Condition of Rafl. Depth of Im- Maximum Pressure in Pounds. Inch 9 89.4 70 B Dry 0.204 10,500 10 87.7 70 B Dry 0.246 13,000 17 92.3 70 B Dry 0.222 11,500 18 90.5 70 B Dry 0.216 11,200 19 85.03 70 B Dry 0.199 10,300 20 79.50 70 B Dry 0.193 10,100 21 75.5 70 B Wet 0.162 8,500 22 80.7 70 B Wet 0.217 11,200 23 81.29 70 B Wet 0.217 11,200 111 85.30 70 B Dry 0.179 9,500 118 80.3 70 B Wet 0.181 9,500 119 83.9 70 B Wet 0.188 10,000 120 83.9 70 B Wet 0.199 10,300 11 81.3 70 D Dry 0.165 8,700 12 83.5 70 D Dry 0.134 7,000 Class B is an Atlantic type locomotive, total weight = 176,600 pounds, height center of gravity above base = 73 inches. Class D is an American type locomotive, total weight = 138,000 pounds, height center of gravity above base = 65 inches. TABLE B. — RESULTS OF COMPUTATIONS MADE BY E. E. STETSON FOR A 1-DEGREE CURVE Speed in Miles per Hour. Speed Corre- sponding to Superelevation. Type of Loco- Pounds. Remarks. 60 70 60 70 60 70 60 60 60 60 60 60 ClaSS B Class B Class A Class A Class C Class C 11,500 12,950 11,120 12,830 13,180 14,700 Class B is an Atlantic type, total weight = 183,150 pounds, height center of gravity above rail taken as 70.5. Class A is Pacific type, total weight 270,100 pounds, height center of gravity above rail = 76.25. Class C is consolidation type, total weight 238,200 pounds, height center of gravity above rail = 62. 24. Effect of the Joint The preceding discussion is based on the assumption that the joint affords 100 per cent efficiency. If we examine the functions the joint performs in carrying the load from one rail to the other, we see that the splice bars, by fitting tightly to the inclined surfaces of the head and base of the rail, are able by their friction to transmit large horizontal strains from one rail to the next. The proportion of the bending moment of the rail transmitted to the splice bar by this means is important in determining the correct proportions of the joint. 260 STEEL RAILS To determine the friction of the bar the following tests were made at the Watertown Arsenal in 1904.* There was first made a series of track observa- tions on the Boston and Albany Railroad at Faneuil station, near Boston, to determine the resistance of nuts on bolts of splice bars as found in the track against further tightening. Tests were made with a wrench 33 inches long, the resistance against tighten- ing being shown by the force required at the end of the wrench to turn the nuts forward. The average of 60 observations was 52 pounds on a 33-inch wrench. Tests were then made at the Arsenal on the frictional resistance of two 6-hole splice bars on two sections of 6-inch 100-pound rail. Spring nuts were used under the nuts, f-inch bolts, 10 threads per inch, length of wrench used 33 inches. The results of the tests are shown in Table LXIX. TABLE LXIX. — FRICTIONAL RESISTANCE OF SPLICE BARS (Watertown Arsenal) Tightening Force Applied to Wrench (Pounds). Frictional Resistance of Joint. Initial (Pounds). Continuous Movement (Pounds). 50 75 37,500 46,900 72,800 72,800 31,000 33,800 44,700 65,500 65,500 28,600 110 — 1 bolt 50 The maximum pull applied to five of the bolts in the third test, 85 pounds on a 33-inch wrench, was the limit of strength of the bolts. This pull on the wrench caused a permanent elongation of about .06 inch to .10 inch on each of the five bolts. The sixth bolt resisted a pull of 110 pounds on the wrench without material elongation. After making observations on the frictional resistance in these tests, the first test, with bolts tightened to 50 pounds' pull, was repeated. The splice bars were now used on one piece of rail, using four bolts, the nuts of which were tightened with a pull of 50 pounds on a 33-inch wrench. The initial resistance was 50,900 pounds and movement continued under 31,200 pounds. Tests with four bolts in one piece of rail, with 50 pounds' pull on the wrench, were repeated with an initial resistance of 59,200 pounds. The movement continued under 41,600 pounds. * House Documents, Vol. 78, No. 291, 58th Congress, 3rd Session, 1904-05, Tests of Metals. STRESSES IN THE RAIL 261 The tension on the bolts was reduced during test, and after the last observa- tions were made the nuts could be further tightened with a pull of 30 pounds. Each nut could be turned up 90 degrees before again attaining a resistance of 50 pounds on the wrench. One-half joint was again made up with four bolts and 50 pounds' pull on the wrench. The initial resistance was 66,500 pounds. The slipping of the angle bars occurred with a series of throbs, immediately followed in each instance by a reduction in the load on the bars. The succeeding throbs took place under gradually diminishing loads, following to 49,300 pounds at the fourth throb. When removed from the testing machine, the nuts could be turned on with an average pull of 35 pounds on the wrench. * The experiments carried out by Messrs. Resal, Poutzen, and Menard on the longitudinal slipping of rails connected by fishplates were of four descrip- tions, viz.: (1) On new rails with new fishplates and bolt holes; (2) On the same rails lubricated with mineral oil; (3) On old rails with worn bolt holes; and (4) On the same with the addition of a thin layer of sand between the surfaces of contact. It was found that the old rails gave the best results and required a pressure of 18 tons to effect any appreciable movement, whereas the new rails were least satisfactory, particularly after oiling. As to the experiment with sand, it was found that, owing to the reduction of the surfaces of contact caused by the sand, the slipping was about the same as in the case of new rails. Dr. P. H. Dudley found that a well-fitted splice bar for a 5-inch rail re- quired over 4000 pounds per linear inch of one-half of the length of the bar to overcome the friction in the rail ends, and for 90-pound and 100-pound 6-inch rail, 4500 and 4800 pounds respectively We are probably not warranted in taking the frictional resistance of the joint at more than 40,000 pounds; nor can the friction between the rail and the splice bar be well increased by the use of special joints, without at the same time increasing to an undesirable extent the stresses in the rail, caused by sudden changes in temperature. It will be seen that this frictional resistance may cause an initial tensile stress of about 4000 pounds per square inch in the 100-pound rail at times of a sudden fall in temperature. * Revue Generate des Chemins de Fer, Paris, 1908, Vol. 31, pp. 8-14. 262 STEEL RAILS The tension set up in rails of lighter section in falling temperatures, before they render in the splice bars, is considered by Dr. P. H. Dudley to be important and indirectly responsible for a large number of the cracked or broken rails which occur during falling temperatures. Records and dates of broken rails taken by Dr. Dudley for a number of years, when compared with the dates of decided falling temperatures, were found to practically coincide, but as soon as the temperature would rise, relieving the rails from tension or putting them in compression, the breakages would cease, except in cases of a development of a check which commenced in a falling temperature. SHEAR Fig. 182. — Shearing Stress in 100-pound A. S. C. E. Rail and Splice Bar. Total Shear, 24,000 Pounds. If we consider the effect of the fractional resistance between the splice bar and the rail, it is apparent that the bar shown in Fig. 182 will act as an integral part of the rail until the longitudinal shear at the surfaces of contact of the rail and the bar exceeds the resistance caused by friction on these surfaces. This resistance for a 20-inch splice bar may be taken as 4000 pounds per linear inch for the entire joint, or 1400 pounds per square inch for STRESSES IN THE RAIL 263 the upper surface of contact, and 500 pounds per square inch for the lower surface of contact. It is seen from the figure that the surface friction is sufficient to carry a total shear at the section of 24,000 pounds, and by referring to the rail diagrams given in Figs. 171 and 172 it would appear that the maximum bending moment in the rail would be transmitted to the splice bars without slipping. However, between the two rails the splice bars must carry the entire moment, and unless the section of the bar is increased at the middle of the joint there results an excessive deflection at this point. Fig. 183. — 100 per cent Joint. Fig. 184. — Joint showing Uneconomical Distribu- tion of Metal. Fig. 185. — Joint showing Economical Distribution of Metal. To overcome this source of weakness in the joint, the form shown in Fig. 183 has been found to embody most of the essential elements demanded by the extra reinforcement needed at the center of the joint. This section is only used at the middle of the bar and the section shown in Fig. 185 is used for the rest of the bar. It will be seen that the added metal is distributed in such a way as to still keep the vertical axis within the vertical surface that is gripped by the bolts. The sectional area and moment of inertia of the reinforcement shown in Fig. 183 can readily be adjusted to match the stiffness of the rail that is to be spliced, whereas, with the space limitations of Fig. 185, it is not possible to get a higher relative percentage of strength than, say, 40, as compared with the rail. The splice bars, shown in Figs. 184 and 185, show the greater stiffness that can be obtained by means of a proper distribution of the metal. Taking the 264 STEEL RAILS stiffness of the rail as 100 per cent, the relative stiffness of the bars, shown in Figs. 184 and 185, is 29.1 per cent and 37.3 per cent respectively.* As far back as 1876 quite full experiments were made with a modified type of reinforcement shown in Fig. E, Plate XXIV, on the Swedish Government Railroads, and in the German handbooks of somewhat later dates quite a variety of sections are found of this same general shape. The reinforcing vertical flange occupied a plane at some distance from the axis of the rail, which causes the vertical axis of the splice bar to assume a position outside the ver- tical surface that is gripped by the bolts, and in consequence the resisting stresses in the flange itself must cause an outwardly rotating action, tending to strip the threads of the bolts. Plate XXIV shows types of joints used in this country, f Fig. A on this plate illustrates the common type of angle bar. The variations from this section, as applied to 80- and 85-pound rail, are in many directions. A com- paratively frequent one is the thickening of the vertical web to f inch. Another tendency is to put more metal into the upper part of the web near the under side of the rail head. An extreme development of this latter practice is shown in the Pennsylvania's angle bar for use with its new section of rail. Fig. B shows this section. The horizontal extension of the lower flange of the bar is another direction in which the angle-bar section is frequently modified. There are six patented joints which are now in service in sufficient numbers to merit consideration. They may be divided into two classes: those with deep girder flanges, namely, the Hundred per cent, the Duquesne, and the Bonzano, Figs. C, D, and E; and those which are base-supporting, as the Continuous, the Weber, and the Wolhaupter, Figs. F, G, and H. The Rail Committee of the American Railway Engineering Association have recently made a series of interesting tests on rail joints at the Watertown Arsenal, f (1) Three joints of each kind were furnished, of which two were used for testing and the third joint was reserved for future use if needed. (2) All joints were full-bolted. Several of the joints first tested had various sized openings between the rail ends. After the test of the first three joints, all other joints were changed so that the opening between the ends of the rails was as close to three-eighths of an inch as possible. The span between supports in the testing machine was 30 inches. * Railroad Age Gazette, April 9, 1909, p. 804. t Railroad Age Gazette, March 19, 1909. % Bulletin No. 123, May, 1910, Am. Ry. Eng. & M. of W. Assn. STRESSES IN THE RAIL 265 (3) One joint was tested with the load first applied to the base, in incre- ments of 2000 pounds, until the limit of 32,000 pounds was reached, and then the joint was reversed and the load applied on the head until the joint failed or the limit of the machine was reached. (4) The second joint was tested by first applying the load on the head and then reversing it, applying the load on the base, until the limit was reached. (5) With the exception of the joints furnished by the Cambria Steel Com- pany and Mr. A. Morrison, the joints were selected from material which had DEFLECTION. J N INCHFS - Diagram of Watertown Arsenal Tests o (Am. Ry. Eng. Assn.) 100-pound Joints. been furnished by the manufacturers to the railroad companies in the regular routine of business, and therefore fairly represent the material ordinarily fur- nished by the manufacturers. Figs. A to F (Plate XXV) show some of the joints tested; the results of the tests on these joints are presented in Fig. 186. The material in the different splice bars varies so widely that it is difficult to judge of the value of the differ- ent designs. The excellent results obtained with the Dudley joint (Fig. D) is probably due to the high strength of the metal as compared to the other joints tested. 266 STEEL RAILS The rolling mills are reluctant to make splices of higher carbon, Bessemer process, than .10 to .20 per cent. Some railroads have specified as high as .63 per cent, and with good results both as to manufacture and experience. The mill, however, suffers by such a high standard. One mill claims to have broken one-third of the total quantity of bars in the straightening process, and it also broke many of the punches. Splices made from steel of .50 carbon appear to give much better results, as might be expected, than the softer steel bars. It is necessary to hot-punch the higher carbon steel, and when this is done there is no difficulty in properly manufacturing them. The Cambria Steel Company are rolling bars of this grade of steel which are hot finished and oil tempered. * The economic advantage of high-carbon steel, hot finished, is that, with the expenditure of about 10 per cent more than the cost of soft steel, a joint is given a carrying capacity that can be equaled only by the addition of double the quantity of metal of soft steel and at the additional cost of 100 per cent. This latter joint will cost 100 per cent more for freight, while there is no addi- tional cost for freight in the former. The oil treatment of steel is a natural sequence of the use of high carbon, and its advantages are about equal to those of high carbon over soft steel. This, however, varies with the section of the bar and hardness of the steel. In economy, oil-treated steel is as much in advance of high-carbon steel as is the latter over soft steel. Intimately connected with the rail- joint problem is the question of the length of the rail. In a recent bulletin (August, 1909) of the International Railway Congress, the practice in English-speaking countries is very fully dis- cussed and abstracts from this report are given below. In Great Britain and Ireland the railways have been gradually increasing the length of rails, with a view to reducing the number of joints. Some rail- ways still use rails only 30 feet long, and a few use 60-foot rails, but a large number have 45-foot rails, and it appears that this may be taken as a standard for the near future. The principal reasons given for limiting the length, as given by the engineers of different railways, may be summarized as follows: (1) Difficulty of straightening rails at the mills; (2) cost of manufacture; (3) difficulties of transportation; (4) expansion and contraction; (5) unloading and handling on the track. So far the use of long rails does not appear to have called for the adoption of any special arrangements other than proper proportioning * Railway Age Gazette, March 16, 1910, daily edition. STRESSES IN THE RAIL 267 of the bolt holes and the play at the joints, and the strengthening of the maintenance gangs (by consolidating neighboring gangs or otherwise) while handling long rails. The temperature varies from 0° F. in winter to a maximum of 130° F. in the sun in summer. To allow free play for expansion during extreme heat, it is the practice of most engineers to ease the joints by slackening the nuts. In the United States the standard length on a number of railways is 33 feet, and the reasons given for limiting the length are, in general, similar to those noted above. Experiments have been made with rails of greater length, but on the whole these have not been satisfactory, although the opinions expressed by some of the railways give 40 feet, 45 feet, 50 feet, and 60 feet as admissible lengths. The range of temperature is 100° F. in some parts of the country, while in others it is 180° F. In some cases the nuts are slackened in the early part of the summer. In the roads of other countries investigated which include 17 railways in South America, India, South Africa, Australia, and Canada, the limiting length of rails varies from 30 to 40 feet. The range of temperature is from 100° to 155° in India, and 160° in South Africa and Australia. Inquiry was made as to whether any railways contemplated welding the rails at the joints. All the replies were in the negative, and the general opinion was that continuous rails would be unsafe, on account of the temperature changes. It is well known, of course, that welding the joint is common practice in street railway work, but in such cases the rails are protected by the paving, so that only a small portion is exposed. The following very interesting report from the Pennsylvania Lines is quoted in the bulletin : " In 1897 a continuous rail, 1050 feet long, made up of 35 80-pound 30-foot rails joined by angle bars with drilled holes and machine-turned bolts (no pro- vision being made for expansion and contraction), was laid in the eastbound main track, near New Brighton, Pa. The ends were held by bent rails bedded in concrete, so placed as to bear against the ties. Special long and wide angle bars were used at the ends, fastened to the anchor ties with lag screws. The track was a tangent with stone ballast. " The rail crept and kinked out of line badly. An examination made in August, 1900, after three years' service, showed that the entire rail crept in the direction of traffic (eastward). At the west anchorage, the vertical holding rails had cut into the cross-ties forming the anchorage framework, while at the east anchorage there was a space of If inches between the vertical rails and the 268 STEEL RAILS framework. All of the spikes were bent eastward, and both slots and spikes were badly cut. The bolts were all slightly sprung. The alignment at the joints was very bad." * The conclusions presented in the bulletin are given below: In Great Britain and Ireland, the lengthening of rails and the consequent reduction of the number of joints has been steadily proceeding at an increasing rate during the past 60 years. In 1840-50, the normal length of rolled iron rails was from 15 to 18 feet. The length of these iron rails increased at the rate of about 3 feet in each decade until 1870-80, when steel rails from 24 to 30 feet long were brought into general use. Since then the decennial increase has been about 4J feet, and at the present time rails 36 feet and 45 feet long are in general use, while two railways have adopted 60 feet in length. In 1904, when the Engineering Standards Committee issued the British Standard sections, it recommended the adoption of the following as the normal lengths of rails: 30, 36, 45, or 60 feet. In other countries embraced by the report, the length of rails has been steadily and uninterruptedly increasing, but within narrower limits than in Great Britain and Ireland. The conclusions to be drawn from the numerous replies and remarks by engineers throughout the English-speaking countries are that there is a maxi- mum length of rail somewhere between 33 feet and 60 feet, which should not be exceeded ; and continuous or welded joints over a long length of railway are impracticable and dangerous. BIBLIOGRAPHY Blum. — Report ... on the question of rail joints. (All countries except France, Belgium, Italy, Spain, Portugal, Austria-Hungary, Rumania, Bulgaria, Servia, Turkey, Egypt, and countries using the English language.) 48 p. 111. 1910. (In Bulletin of the International Railway Con- gress, Vol. 24, Part 1, p. 1701.) Bouchard, H. — Note sur le joint asymetrique. 4000 w. 111. 1909. (In Revue generate des chemins de fer, Vol. 32, p. 9.) Describes theory, construction, and results with favorable rail joint. Chateau. — ■ Report ... on the question of rail joints (France, Belgium, Italy, Spain, and * The author several years ago had experience with a continuous rail designed by the late Mr. Torrey. The rail was about the length and of the same weight as in the Pennsylvania test. It was laid on a branch line of the Michigan Central Railroad on a tangent and ballasted with a good bed of gravel. Provision was made at intervals of about 500 feet throughout the test track for the expansion of the continuous rail by means of special expansion joints, the rail being anchored midway between these joints. " When first installed the riding qualities of the track were exceptionally good, which may, however, have been accounted for by the unusual care that had been taken in constructing it. After several years the test track appeared to ride about as well and to require the same amount of attention as the other track on the division. STRESSES IN THE RAIL 269 Portugal). 38 p. 111. 1910. (In Bulletin of the International Railway Congress, Vol. 24, Part 1, p. 1427.) Edelstein, Leon. — Prevention of play between rail and fishplate. 2000 w. 111. 1908. (In Bulletin of the International Railway Congress, Vol. .22, Part 1, p. 436.) Shows faults that develop with wear, and gives suggestions for prolonging life of both rails and fishplates. Godfernatjx, R. — Note about rail-joints. 24 p. 111. 1911. (In Bulletin of the Inter- national Railway Congress, Vol. 25, p. 1480.) Reviews development of rail joints and different forms used. Haarmann, A. — Der schienenstoss. 5000 w. 111. 1911. (In Stahl und eisen, Vol. 31, Part 1, p. 49.) Discusses types of rail joints and probable future practice in track construction. Improvements and experiments in rail joints. 2500 w. 1910. (In Engineering News, Vol. 64, p. 281.) Abstracts information from reports to International Railway Congress on practice in the United States, Great Britain, France, Belgium, and Austria-Hungary. International Railway Congress. — [General discussion on rail joints.] 38 p. 1911. (In Bulletin of the International Railway Congress, Vol. 25, p. 405.) Kramer, Friedrich. — Report ... on the question of rail-joints (Austria, Hungary, Rumania, Bulgaria, Servia, Turkey, and Egypt). 82 p. 111. 1910. (In Bulletin of the International Rail- way Congress, Vol. 24, Part 1, p. 1967.) Jones, Cyril Walter Lloyd. — Design of fishplate rail joints. 7000 w. 111. 1910. (In Minutes of Proceedings of the Institution of Civil Engineers, Vol. 182, p. 282.) Pellarin. — Etude des joints des rails. 27 p. 111. 1908. (In Annales des ponts et chaussees, Memoires, series 8, Vol. 33, p. 9S.) Report of commission for investigation of rail joints in Belgium, Italy, Switzerland, and Holland. Ross, Alexander. — Report ... on the question of rail joints. (Countries using the English language.) 44 p. 111. 1909. (In Bulletin of the International Railway Congress, Vol. 23, Part 2, CHAPTER V strength of the rail 25. Influence of Stress and Strain on the Strength of the Rail In determining the safety of any structure, not only the amount of stress induced in the different members by the load must be found, but its character and the effect it may produce on the material of which the structure is composed must be considered. A series of rapidly repeated stresses will, under certain conditions, affect the breaking strength of the metal. The cause of this loss of strength under the influence of repeated stress is a much-mooted question among engineers, and it is of interest to examine the problem in detail.* Fig. 187. — Pure Swedish Iron. (Mellor.) Fig. 188. — Pure Copper. (Arnold.) The junction of the crystalline grains of pure iron, shown in Fig. 187, and of pure copper, shown in Fig. 188, are typical of pure metals; but when impuri- ties are present the crystals of the pure metal, in the act of crystallizing, reject the impurities which collect at the crystal boundaries. The particles of pure metal slowly migrate and coalesce together, so as to form little islands sur- rounded by the impurity; accordingly, in the solidified mass, we find the crystals of pure metal enveloped by a film of the metal associated with the foreign sub- * The author is indebted for the discussion on pp. 270-276 to Mr. J. W. Mellor's work, The Crys- tallization of Iron and Steel, Longmans, Green & Co., London, 1905. 270 STRENGTH OF THE RAIL 271 stance. This investing membrane separates the crystals of pure metal one from the other. Obviously, the mechanical and physical properties of the alloy will depend upon the character of the film. The mass of pure metal, for example, may be quite ductile like gold, while the mass of metal with the impurity may be quite brittle, as Arnold * found to be the case with an alloy of gold with .2 per cent of bismuth; and copper containing .5 per cent bismuth. A representation of the latter alloy is shown in Fig. 189. When such a metal is fractured, the line of fracture follows the junction of the grains. Stead calls this ailment intergranular or intercrystalline weakness (inter, between). We have had examples. Arnold's work on the influence of bismuth Fig. 189. — Copper-bismuth Alloy. (Arnold.) - Iron with 1.8 per cent Carbon. (F. Popplewell.) on copper and on gold. One per cent of sulphur arranged as a mesh of iron sulphide will entirely destroy the ductility of the iron, reducing the ultimate stress from 20 to 2 tons per square inch. The network of cementite which envelops the crystal grains of steel con- taining over 1 per cent of carbon are the principal lines of weakness. The metal when fractured generally breaks through the center of this brittle envelope. The coefficient of contraction of the cementite cell walls is greater than of the cell contents. Pearlite cells, for example, bound together by thick cementite walls (Fig. 190), are liable to rupture, because the coefficient of contraction of the cementite cell walls is greater than the cell contents. The mass is, in con- sequence, very feebly held together, and a sudden blow will easily fracture the metal.t * J. O. Arnold and J. Jefferson, Engineering, 61, 177, 1896. t J. O. Arnold, Metallographist, 5, 267, 1902. 272 STEEL RAILS Intergranular weakness resembles the weakness of a brick building with faulty mortar. There is another type of intergranular weakness which is due to imper- fect union of the crystal grains. This is particularly marked in phosphorous steels. The crystal grains, on cooling, contract unequally and tend either to draw the grains away from each other or to leave the mass in a state of unnatural tension. The fracture then follows the granular junctions. Thick plates and bars are frequently brittle because comparatively little work has been done on them. The crystals are not interlocked one with another, as in steel which has been well worked. Intergranular weakness may, therefore, be of two kinds: (1) Brittle envelope surrounding the crystal grains; (2) Imperfect union of the crystal grains. Stead has pointed out another type of weakness in sheet steels which has to do with the crystals themselves, without reference to the union of one crystal with another. It is a kind of intracrystalline weakness (intra, within). It is characteristic of some crystals to break more readily in some directions more than in others. This property of crystals is called cleavage. The direc- tions in which the crystal splits are called cleavage planes. If a bar of iron could be cut from a single crystal, that bar would have three lines of weakness in the direction of the three cleavage planes; while if the bar were built up of a number of crystals whose cleavage planes were all in the same direction, that bar would be more readily broken in the direction of its cleavage planes, neglect- ing for the moment intergranular weakness. On the other hand, if the cleavage planes of the adjacent crystals are inclined at considerable angles to one another the bar would be less liable to break than one in which the crystals were arranged symmetrically. Figs. 191 and 192 will make this clear. The dotted lines ab, Fig. 191, represent the cleavage planes across a sheet of iron when the crystals are arranged symmetrically, while in Fig. 192 the crystals are arranged in an irregular manner. The cleavage planes of Fig. 191 run along parallel lines, and the sheet would, therefore, be more liable to rupture than the sheet shown in Fig. 192, where the lines of weakness are not in the same direction, and this in spite of the fact that Fig. 191 has a finer grain. Other things being equal, a fine-grained structure is stronger and tougher than a coarse-grained piece. Figs. 191 and 192 show that this order of things may be reversed. Fortunately, the crystals of one steel do not generally grow symmetrically. STRENGTH OF THE RAIL 273 Fig. 191. — Cleavage Planes with Crystals ar- Fig. 192. — Cleavage Planes with Crystals arranged [ Symmetrically. (J. W. Mellor.) in an Irregular Manner. (J. W. Mellor.) Fig. 193. — Iron strained beyond the Elastic Limit. (J. A. Ewing and W. Rosenhain.) Fig. 194. — Lead strained beyond the Elastic Limit. (J. A. Ewing and W. Rosenhain.) Examining now what takes place in the metal under repeated stress, Ewing and Rosenhain * found if a metal is strained past its " yielding point " — elastic limit — the faces of the crystal grains (Fig. 193) show fine black lines, which increase in number as the strain increases. Lines appear on certain crystals nearly transverse to the pull, as the strain increases lines appear upon other * J. A. Ewing and W. Rosenhain, Phil. Trans., 193, 353, 1899; 195, 279, 1900. J. A. Ewing and J. C. W. Humfrey, Ibid., 200, 241, 1902. W. Rosenhain, Journal Iron and Steel Inst., 67, i, 335, 1904. F. Osmond and C. Fremont and G. Cartaud, Revue de Metallurgie, 1, i, 1904. 274 STEEL RAILS grains. Intersecting lines then make their appearance on some of the grains. Such a strained surface is shown in Fig. 194. The lines are apparently not actual cracks in the surface, but rather slips along the cleavage planes of the crystal. They are called slip bands, or slip lines. Let AB (Fig. 195) represent a cross section through a polished surface of metal. Let C be the junction between two contiguous grains, A and B. When the metal is pulled in the direction of the arrows, a number of slips are developed along the cleavage planes, a,b,c,d. . , and the surface now presents Fig. 195. — Cross Section of Unstrained Metal. Fig. 196. — Cross Section of Metal after being (J. W. Mellor.) Stressed. (J. W. Mellor.) the appearance shown in Fig. 196. With still greater strains the slip bands develop into actual cracks, and rupture takes place. Hence it follows that under progressively augmented strain, rupture takes place, not at the crystal boundaries, but through the crystals themselves. Ewing and Humfrey have subjected Swedish, iron, with a breaking stress of 23.6 tons per square inch, to a series of compression and tension stresses, 9 tons in magnitude, repeated 400 times per minute. On examination it was found that fine slip bands appeared in a few crystals after a few, say, 5000 reversals of stress; with a greater number, say, 40,000, the slip bands increase in number, and those which first appeared broaden and develop into small cracks, as shown in Fig. 197. If the specimen be repolished, so as to clear off the slip bands, the cracks alone become visible, as at A (Fig. 198). The crack, or flaw, gradually creeps across the specimen when the number of alternations is still further increased, as shown in Fig. 199. Finally the specimen breaks. Ewing and Humfrey state: " Whatever the selective action of the stress is due to, the experiments demonstrate that in repeated reversals of stress certain crystals are attacked, and yield by slipping, as in other cases of non- elastic strain. Then, as the reversals proceed, the surfaces upon which the slipping has occurred continue to be surfaces of weakness. The parts of the crystal lying on the two sides of each such surface continue to slide back and forth over one another. STRENGTH OF THE RAIL 275 Fig. 197. — Slip Bands. (J. W. Ewing and J. C. W. Humfrey.) I \* r. h. -A Fig. 198. — Polished Surface with Small Cracks. (J. W. Ewing and J. C. W. Humfrey.) 276 STEEL RAILS " The effect of this repeated sliding or grinding is seen at the polished surface of the specimen by the production of a burr or rough and jagged irregu- lar edge, broadening the slip band, and suggesting the accumulation of debris. Within the crystal this repeated grinding tends to destroy the cohesion of the metal across the surface of the slip, and in certain cases this develops into a crack. " Once the crack is formed, it quickly grows in a well-known manner, by tearing at the edges, in consequence of the concentration of stress which Fig. 199. — Polished Surface with Large Cracks. (J. W. Ewing and J. C. W. Humfrey.) results from lack of continuity. The experiments throw light on the known fact that fracture by repeated reversals or alternations of stress resembles fracture resulting from ' creeping flaw ' in its abruptness, and in the absence of local drawing out, or other deformation of shape." * The rupture of steel is not caused by the gradual growth of the crystal- line structure of the metal under the influence of shocks and vibrations. The breaking down is due to fatigue. When fatigued, the metal breaks more readily. Again, when subjected to sudden shock, the metal has no time to " flow." The * P. Kreuzpointer, Journ. Franklin Inst., P. Breuil, Suppl. Journ. I. & S. Inst., 1904. 153, 233, 1902. J. A. Ewing, Nature, 70, 187, 1904. STRENGTH OF THE RAIL 277 slipping of the crystal planes, or the plasticity of the metal, has no time to come into play. The metal, in consequence, appears to be abnormally brittle. * The experiments made by Wohler, from 1859 to 1870, were the first that indicated the laws which govern the rupture of metals under repeated applica- tion of stress. For instance, he found that the rupture of a bar of wrought iron by tension was caused in the following ways : By 800 applications of 52,800 pounds per square inch. By 107,000 applications of 48,400 pounds per square inch. By 450,000 applications of 39,000 pounds per square inch. By 10,140,000 applications of 35,000 pounds per square inch. Here it is seen that the breaking unit stress decreases as the number of applications increases. It was further observed that a bar could be strained from up to a stress near its elastic limit an enormous number of times without rupture, and it was also found that a bar could be ruptured by a stress less than its elastic limit under a large number of repetitions of stress which alternated from tension to compression and back again. f The apparatus used by Wohler and his successor, Spangenberg,! was of four kinds: (1) To produce rupture by repeated load; (2) For repeated bending, in one direction, of prismatic rods; (3) For experiments on loaded rods under constant bending stress; (4) For torsion by repeated stress. The amount of the imposed stress was determined by breaking several rods of like material, ascertaining the breaking load, and taking some fraction of this for the intermittent load. From the results of these experiments of Wohler, extending over eleven years, the following law was deduced: " Wohler's Law: Rupture of material may be caused by repeated vibra- tions, none of which attain the absolute breaking limit. The differences of the limiting strains are sufficient for the rupture of the material." The work of Wohler and Spangenberg has proved what was long before supposed to be the fact: that the permanence and safety of any iron or steel structure depends not simply on the greatest magnitude of the load to be sus- tained, but on the frequency of its application and the range of variation of its amount. * A. Wohler, Engineering, 1871 ; Zeitschrift fur Bouwesen, 1870, p. 83, Berlin, t Iron and Steel, Materials of Engineering, Part 2, Thurston, 1909, p. 618. t Zeitschrift fur Bouwesen, 1874, p. 485, Berlin. 278 STEEL RAILS Prof. L. Spangenberg resumed the line of experiments at the point of its discontinuance by Wohler, and his results tend to confirm the law of the latter. Spangenberg directed his attention to other metals than iron and steel, and also endeavored, by inspection of the surfaces of fracture, and by his hypoth- esis as to the molecular constitution of metals, to explain the phenomena of fracture. Among the several observations noted in his " Fatigue of Metals " is the important fact that when subjected to often-repeated transverse stress fracture of iron took place only on the tension side of the bar and extended only to the neutral axis. From this he inferred that the working strength of wrought iron is less than its elastic resistance. Fowler states, in this connection, that a steel rail tested for transverse strength in a machine will, as a rule, bend many inches, and fail by distortion of the head under the compressive stress. In actual work hundreds of such rails break, but it is the tensile and not the compressive stress which causes the failure, and there is no distortion of the head, as in the testing machine. Reynolds and Smith * extended Wohler's conclusions to steel bars tested under direct tension and compression and at a rapid rate of alternation. The work of Stanton and Bairstow,f published in 1906, while less concordant than that of Reynolds and Smith, confirms their general conclusions; it extends the conclusions of Ewing and Humfrey to notched specimens tested for endurance under direct tension and compression, and it clearly points out the advisability of testing a material for endurance in approximately the form in which it is to be used in practice. French engineers, commenting upon the work of Wohler, Spangenberg, Weyrauch,^ and Launhardt, consider that the result is simply to base upon the ultimate strength a deduced limit of working stress which corresponds closely to the elastic limit, and generally urge the use of a reasonable factor of safety related to the limit of elasticity.! Figs. 200, 201, and 202 present three diagrams on the behavior of steels under repeated alternate stresses, illustrating some of the tests which have been made at the Watertown Arsenal laboratory.) | On Fig. 200 the heavy vertical lines represent the number of loads which were applied to a number of steel bars of .55 per cent carbon, and which * Phil. Trans. Royal Society of London, A- Vol. 199, p. 265, 1902. t Proceedings Inst, of Civil Engrs., Vol. 166, p. 78, 1906. t Various Methods of Determining Dimensions. Dr. J. Weyrauch; translated by G. R. Bodmer. Proc. Inst. C. E., 1882-83, Vol. LXXI. § Resume de la Societe des Ingenieurs Civils, 1882. II Notes on the Endurance of Steels under Repeated Alternate Stress. Howard, Proceedings Am. Society for Testing Materials, 1907, Vol. VII. STRENGTH OF THE RAIL 279 caused rupture of the metal. Beginning with the highest fiber stress, 60,000 pounds per square inch, the progressive gain in endurance of the steel as the loads were successively reduced will be noted, as indicated by the lengths of the different lines. The lowest fiber stress experimented with did not end in REPEATED ALTERNATE STRESSES O .55 CARBON STEEL. TENSILE TEST ELASTIC LIMIT 59,000 LBS PER S0UNCH TENSILE STRENGTH 111,200 ELONGATION 12 PER CENT CONTRACTION 33.5 30,000 35,000 40,000 45,000 50,000 60,000 FIBRE STRESSES. LBS. PER SQUARE INCH. Fig. 200. — Behavior of 0.55 Carbon Steel under Repeated Alternate Stresses. (Am. Soc. for Testing Materials. — . Howard.) REPEATED ALTERNATE STRESSES .82 CARBON STEEL., TENSILE TEST ELASTIC LIMIT 64,0 00 LBS. PER SDJNCH TENSILE STRENGTH 142,800 - •• - •• ELONGATION 7 PER CENT CONTRACTION 11.8." ii 40,000 45,000 50,000 55.000 60.000 FIBRE STRESSES, LBS. PER SQUARE INCH •K: NOT RUPTURED Fig. 201. — Behavior of 0.82 Carbon Steel under Repeated Alternate Stresses. (Am. Soc. for Testing Materials. — Howard.) rupture of the shaft; after 76 million repetitions, in round numbers, under a load of 30,000 pounds per square inch, the fiber stress was increased to 60,000 pounds per square inch, which higher load caused rupture after about 8000 rotations. The enormous gain in endurance of the steel, under 30,000 pounds fiber stress, over its behavior with the higher loads, would be represented by a vertical line about 28 feet in height, according to the scale of this diagram. The results of the tensile tests of this grade of steel are entered on the diagram, 280 STEEL RAILS from which it may be seen that the several fiber stresses were, with one exception, below the tensile elastic limit of the metal. On Fig. 201 similar lines represent the behavior of specimens containing .82 per cent carbon. The behavior of this grade resembles that of the previous diagram, and similar to other steels belonging to this series of experiments. The endurance under corresponding loads is seen to be greater than displayed on the preceding diagram. After making 202 million rotations the test of the shaft loaded with 40,000 pounds was temporarily discontinued, the steel being unruptured. A line drawn to scale to represent the endurance under this load would be about 73 feet in height. On Fig. 202 appear curves representing the relative endurance of each of the six grades of steel used in this series of experiments. Their endurance under the higher fiber stresses only are shown, loads which caused compara- tively early rupture of the steel in most of the tests. It may be remarked that the fiber stresses experimented with were gener- ally below the tensile elastic limits of the steels. The greater endurance of the steels of .73 and .82 per cent carbon in comparison with either the higher or the lower carbons is an interesting feature of the tests. Elastic properties only are displayed by steels, prior to rupture when rup- ture is caused by a large number of alternate stresses of tension and compression ; no appreciable display of ductility, as shown by elongation and contraction of area, need precede rupture, in any grade of steel, following the application of stresses of this kind. If the fiber stresses somewhat exceed the tensile elastic limit, a limited display of elongation, other than elastic, may occur, but rupture caused by loads which are in the vicinity of or below the tensile elastic limit is not attended with an appreciable display of ductility. While tests by repeated alternate stresses are characterized by the absence of ductility, as witnessed in tests by tension, there may be elastic movements of the metal aggregating considerable distances. The aggregate extension of the most strained fiber of the .82 per cent carbon steel which has successfully endured 202 million repetitions amounts to nearly 5 miles per linear inch of specimen, a distance quite incomparable to the permanent extension of the metal in the tensile test. * Little attention seems to have been given to the possibility of finding a relation connecting the stress used in endurance tests with the number of repetitions required for rupture. Spangenberg, Reynolds, and Smith, and * The Exponential Law of Endurance Tests, O. H. Basquin, Proceedings of the American Society for Testing Materials, 1910, Vol. X, p. 625. STRENGTH OF THE RAIL 281 Stanton and Bairstow, have shown stress-repetition curves drawn to ordinary Cartesian coordinates. Logarithmic coordinates present a distinct advantage' in the study of simple exponential curves, because these curves become straight lines for these REPEATED ALTERNATE STRESSES. i ■ 40.000 FS i 1 m l 1 ^' V I 1 en hi o IS o r ol <1 1 coj 1 ^f / /. 60,000 LBS ^Sffr a£^ GRADE .17 C. E.L. 51000 .3.4C. .55 C. .73C. 54,000 59,000 B4.000 .82C. I09C. 64.000 77.000 Fig. 202. — Comparison of the Behavior of Different Grades of Steel under Repeated Alternate Stresses (Am. Soc. for Testing Materials. — Howard.) coordinates and their equations may be written at once. Fig. 203 shows stress-repetition curves for nineteen sets of endurance tests, made by five dif- ferent observers. The names of the experimenters, the kind of test, and the material are given in Table LXX. 282 STEEL RAILS TABLE LXX. — EXPERIMENTS ON REPEATED STRESS (Basquin) Letter. —■ ■ Kind of Test. Material. Coefficient (Thousands) C. Exponent A B Wohler b b b b b b c b b d b b b b Wrought-iron axles, Phoenix Co . . . . Wrought-iron axles, Phoenix Co. . . . 217 109 103 94 130 36 29 1000 920 320 310 90 97 115 250 102 66 110 150 135 -0.12 10' C* -0 09 D* Cast steel, Borsig Homogeneous iron, P. C. & Co Bar copper, Heckmann Cast iron, locomotive cylinder Krupp's spring steel, hardened Krupp's spring steel, unhardened. . . Krupp's axle steel 11 E << -0 12 F n 08 G << —0 09 H << J -0 21 K] << L\ 18 M " 07 N P Benjamin Baker Reynolds & Smith . . Bars from Forth Bridge -0.10 15 QX 13 Annealed mild steel -0.11 T Steel A, grooved Steel B, grooved -0.15 u " * C has round shoulders near grip ; D has square shoulders, t K has round shoulders near grip; L has square shoulders, t Ordinates are " Half Range of Stress," instead of maximun § Carbon, 0.32 per cent ; yield point, 39,000 pounds per squan ich. Most points show the n: Kinds of Tests : (a) Bending in one direction only (+ and 0). (b) Rotating under bending load (+ and — ). (c) Tension only (+ and 0). (d) Bending back and forth (+ and — ). (e) Tension and smaller compression (+ and — ). The curve A is represented by the equation S = 217,000 R-° 12 , which has the form S = CR n , in which S is the maximum stress used in each test and R is the number of repe- titions of this stress required for rupture. The coefficient, 217,000, was found by extending the line A to the left until it intersected the vertical line R = 1 (i.e., 10°), and the stress at this intersection was read off the logarithmic scale as 217,000 pounds per square inch. The coefficient is the stress given by the curve for a single repetition. All the coefficients given in Table LXX in the column marked C were found in the same way. The value of the exponent, —0.12, was found by measuring the angle (130°) which this line makes with the hori- zontal axis and then taking one-tenth of its natural tangent. The factor " one- tenth " comes in because, in Fig. 203, the scale used along the vertical axis STRENGTH OF THE RAIL 283 in plotting the stresses is ten times the scale used along the horizontal axis in plotting the repetitions. In the same way the exponent for each curve of Fig. 203 has been found and is listed in the table under the column marked n. In looking over the curves, Fig. 203, it is evident that in many cases the straight line represents the results of endurance tests very accurately through- out a considerable range of stress. One is also impressed with the approximate Fig. 203. — Number of Repetitions before Rupture in Endurance Tests of Metals. (Am. Soc. for Testing Materials. — Basquin.) parallelism of many of these lines. Curves B, C, D, E, F, G, M, N, and S represent tests made in much the same way, — by rotating a specimen under bending load. The curve for hard steel, tested by Baker * in much the same way, has a steeper slope; the same is also true of the grooved specimens tested by Foppl.f Curves H, J, K, and L are approximately parallel and represent tests in one direction only; i.e., the stresses are not reversed. They have about * Some notes on the Working Stress on Iron and Steel, Trans. Am. Soc. of Mech. Engrs., 1887, Vol. VIII, p. 157. t Mitteilungen aus dem Mech. Engrs., Vol. 130, 1909. 284 STEEL RAILS double the slope of the other curves mentioned. Why curve A, on wrought iron, does not fall into this class is not clear. * Small changes in temperature occur when a bar of metal is stressed within the elastic limit; it becoming cooler under tension and warmer under compression. The measurements of these changes made by Turner, in 1902, have shown that these changes in temperatures continue at a uniform rate up to about three-fifths of the elastic limit, and that then a marked change occurs, the bar under tension then beginning to grow warmer, while the temperature of the bar under compression increases at a more rapid rate. It thus appears for stresses higher than above three-fifths of the elastic limit, at least, energy is converted into heat under repeated applications; prob- ably this occurs also at lower stresses when repeated stresses range from ten- sion into compression in a bar, or when a beam is subjected to alternating flexure. In the case of the rail the bending stress alternates about in the proportion of 4 to 1, and it is very probable that by taking a unit stress less than half the elastic limit, we may safely ignore the effect of fatigue on the metal of the rail produced by this stress. The disturbed metal at the running surface of the head which is frequently conspicuous in old rails is evidence of the elastic limit of the metal being exceeded rather than the effect of repeated stress below this limit. Generally speaking the effect of repeated stress is not to produce distortion of the metal, and prior to rupture elastic properties only are displayed. 26. Effect of Low Temperatures on the Strength of the Rail Very complete investigations were made to determine the effect of changes of temperature in modifying the physical properties of iron and steel by Styffe and Sandberg. f The conclusion of Styffe is that the strength of iron and steel is not diminished by cold. Arguing from these experiments, investi- gators have assumed that the cause of the frequent breakage of rails in cold weather, and of articles made of iron and steel, is unequal expansion and con- traction and the rigidity of supports, where, as in the case with rails, frost may very greatly affect them. J Sandberg, while admitting the care and the accuracy which distinguished this extensive series of experiments, still doubted whether the reasons just * Mechanics of Materials, Merriman, p. 354, New York, 1905; and Trans. Am. Soc. of Civil Engrs., Vol. XXVIII, 1902, p. 27, Thermo Electric Measurements of Stress, Turner. t The Elasticity, Extensibility, and Tensile Strength of Iron and Steel, by Knut Styffe, trans- lated from the Swedish, with an original appendix by Christer P. Sandberg; with a preface by John Percy, M.D., F.R.S., London, 1869. (Sandberg's investigations appear in the appendix.) % Iron and Steel; Materials of Engineering, Thurston, 1909 p. 556. STRENGTH OF THE RAIL 285 given were the sole reasons why metals should more readily break in cold than in hot weather, and, having obtained the consent of the State Railway Adminis- tration, he conducted a series of experiments in the summer and winter of 1867, at Stockholm, to determine whether, with equal rigidity of supports, iron rails would yield with equal readiness to blows at the two extremes of temperature. The rails experimented upon were each cut in halves, and one piece was tested in cold and the other in warm weather, at temperatures of 10 degrees and 84 degrees Fahr. respectively. The supports at the end of the rails were granite blocks placed four feet apart, and resting on the smoothly leveled surface of the granite rock. They were broken by a heavy drop weighing 9 cwt. Sandberg's conclusions from twenty experiments are thus given: " (1) That for such iron as is usually employed for rails in the three principal rail-making countries (Wales, France, and Belgium), the breaking strain, as tested by sudden blows or shocks, is considerably influenced by cold, such iron exhibiting at 10 degrees Fahr. only from one-third to one-fourth of the strength which it possesses at 84 degrees Fahr. " (2) That the ductility and flexibility of such iron is also much affected by cold; rails broken at 10 degrees Fahr. showing, on an average, a perma- nent deflection of less than one inch, whilst the other halves of the same rails, broken at 84 degrees Fahr., showed a set of more than 4 inches before fracture. " (3) That at summer heat the strength of Aberdare rails was 20 per cent greater than that of the Creusot rails, but that in winter the latter were 20 per cent stronger than the former." Sandberg suggests that this considerable lack of toughness at low tem- peratures may be due to the "cold-shortness" produced by the presence of phosphorus. Jouraffsky, of St. Petersburg, has reported* the results of tests of rails made for the Russian government, which supplement the preceding in a very valuable manner. It was found that by placing pieces of rail from 6 feet to 8 feet long in a mixture of ice and salt, the temperature of the rail could be lowered in a very short space of time, during warm weather, 36 degrees Fahr. below freezing point. A special commission, Messrs. Erakoff, Beck, Guerhard, Nicolia, and Feo- dossieff, was appointed to carry out a series of tests on this plan. Pieces of rail 6 feet long were taken in pairs, one of which was tested at the natural temperature, the others being placed in a box filled with a mixture of * Communicated to the London Meeting of the Iron and Steel Institute, 1879. 286 STEEL RAILS two parts of broken ice and one part of salt, and, after being cooled to a temperature of from +3 degrees to -6 degrees Fahr., which occurred in half an hour, they were all submitted to the same tests. Altogether, 86 samples were tested, and these were, for the sake of comparison, divided into two groups, viz.: (1) Rails which broke under the test; and (2) rails which stood the test. The results indicated that the brittleness of the steel increases very much at low temperature if it contains more than a moderate amount of phosphorus, silicon, and carbon. The total of the three elements in the rails which broke under the test averages 0.54 per cent, and in those which stood the same test 0.41 per cent, the first average (0.54 per cent) varying from 0.44 to 0.67 per cent, and the second average (0.41 per cent) varying from 0.37 to 0.55 per cent. The tests on steel at different temperatures made at the Watertown Arsenal in 1888,* showed within the range of 0.37 to 0.71 per cent carbon a slight increase in the elastic limit and tensile strength at degrees Fahr. above that at summer heat, accompanied by very little change in the elongation or contraction of area. Dr. P. H. Dudley recommends the use of basic open-hearth rails of 0.62 to 0.75 carbon with phosphorus under 0.04 to insure a more uniform range of toughness and ductility of metal where exposed to low temperatures than has been obtained in plain Bessemer with 0.50 carbon and 0.10 phosphorus. Tests of Bessemer heats were made in which one-tenth of one per cent of metallic titanium was added to the steel and the carbon increased from 0.50 to a range of 0.60 or 0.70, the metal having higher physical properties and tough- ness at the same time. The manganese and silicon are lowered slightly to prevent shrinkage cavities in the ingots. Tests were made under the drop comparing the ordinary Bessemer rails and this grade of steel cooled to zero temperatures, and some specimens were also cooled to 22 degrees Fahr. below zero. The tests of the Bessemer steel with the one-tenth of one per cent of metallic titanium withstood a drop of 2000 pounds, falling sixteen feet without breaking, while the plain Bessemer would fail at the low temperatures at about one-half that height. Dr. Dudley f considers that basic open-hearth rails (C = 0.68; Mn = 0.86; Si = 0.10; P = 0.012) which show ductility ranging from 15 to 20 per cent under the drop test are proper for use under high-speed trains where the tem- perature in winter falls to 20 degrees Fahr. below zero. * Tests of Metals, 1888, House Doc. No. 45, 50th Congress, 2nd Sess., p. 505. t Dudley on Ductility Tests on Rails. Proceedings American Society for Testing Materials, Vol. X, 1910, p. 229. STRENGTH OF THE RAIL 287 The question of obtaining a proper amount of ductility in rails, used in cold climates, is a very important one. The experience of the railroads in the Northern and Western States, during the very cold weather of the winter of 1911-1912, was more severe than ever before reported. The effects were so great that rails which had heretofore been quite free from breakages were broken in considerable quantities by the wheels of the passing trains. The record of rails of large ductility or tenacity and toughness, on the other hand, showed a much greater freedom from breakages. With the recently adopted standard drop-testing machine (see Article 27) the ductility of the rail can be measured with much more accuracy than was possible in the machines which preceded it. With the older machines the re- bound of a 2,000-pound hammer was as large as 12 to 14 inches, while in the present machine it is confined to 3 or 4 inches. The maximum elongation per inch can be obtained by stamping the base, head, or edge of the base of the butt, as the case may be, before testing with a spacing bar of six inches, directly under the point of impact for either a single blow or for two or more required to exhaust the ductility of the metal. These six inches include about two-thirds of the metal affected by the impact. The elongation in the base of a 6-inch, 100-pound rail, with a moment of inertia of 48.5, under a single blow for an 18-foot fall in the present drop-testing machine, will be from 6 to 7 per cent for a steel of 0.50 carbon, 0.10 phosphorus, and 1.00 manganese. The elongation of the metal under the drop-testing machine compares favorably with that obtained by static loads in the tension machine. The tendency is an increase of possibly one or more per cent, owing to the fact that the base of the rail in stretching does not neck as in the case of a tensile specimen. To raise the mean ductility, it has been found necessary to reduce the average percentage of carbon in heavy sections to 0.50, when the phosphorus content is 0.10, for rails which are to be used where the temperatures fall below zero. The Bessemer rails, owing to the greater content of phosphorus, oxides, and nitrogen, show a greater tendency to irregular low ranges of ductility than the basic open-hearth rails. The use of ferro-titanium in Bessemer steel, to take up a large percentage of the oxides and also a part of the nitrogen, makes it possible to increase the carbon content without any sacrifice to the ductility.* Probably "some of the failures of rails in cold weather can be attributed to the effect, already noted in article 24, of the contraction of the metal, which may set * The subject of ductility in rail steel has been reported upon very fully by Dr. P. H. Dudley in papers presented to the American Society for Testing Materials, see Proceedings, Vol. X, 1910, pp. 223-232, and Vol. XI, 1911, pp. 454-461. 288 STEEL RAILS up tensile stresses of some magnitude in the rails before the ends render in the splice bars. The effect of frost, in heaving the track where the ballast or subgrade con- tains much moisture, is to cause an irregular surface and, on account of some of the ties rising or "heaving" above the others, often produces larger bending moments in the rail than would be expected if the ties were free to adjust them- selves to the elastic curve of the rail. In the case of well-drained track, on stone ballast, where heaving is absent, smaller bending moments will be found in the frozen track than when in its natural condition. 27. Physical Tests of the Strength of the Rail The impact hammer or drop test, introduced by Sandberg and Styffe, in 1868, is most generally used in this country in testing the strength of the rail. From the very prominent place given drop tests in rail specifications,* it might be seen that the behavior of the rail under the drop test is generally regarded as valuable information as to its character. As a matter of fact, however, engineers differ widely as to the advisability of accepting this test as an index to the reliability of the rail, on account of the great variation in the results obtained. The test shows, it is true, whether the piece being tested is brittle or not, and by observation of the permanent set, whether the steel Note. For an account of the state of knowledge relating to impact tests and for a bibliography of literature, reference is made to the following: American Section, International Association for Testing Materials: Bulletin No. 5, October, 1899. Report of Committee on Present State of Knowledge Concerning Impact Tests. W. K. Hatt and Edgar Marburg. Bibliography on Impact Tests and Impact Testing Machines. Proceedings American Society for Testing Materials, Volume II, page 283. W. K. Hatt and Edgar Marburg. The Resistance of Metals under Impact. Mansfield Merriman. Proceedings American Association for the Advancement of Science, Volume 43, 1894. Theory of Impact and its Application to Testing Materials. H. D. Tiemann. Journal of the Franklin Institute, October and November, 1909. International Association for Testing Materials, Vth Congress, Copenhagen, 1909. Impact tests papers, III,, III 2 , Ills, IIL, IIL, His, IIL, Ills. Elongation and Ductility Tests of Rail Sections under the Manufacturers' Standard Drop- Testing Machine. P. H. Dudley, Proceedings American Society for Testing Materials, Vol. X (1910), p. 223. The Same. Iron Trade Review, Vol. 47, p. 410. Nouvelle Methode d'essai des Rails, Ch. Fremont Genie Civil, Vol. 59 (1911), p. 7, 26, 48, 72. The same. Railway Age Gazette, Vol. 51, p. 1176. New Types of Impact Testing Machines for Determining Fragility of Metals. T. Y. Olsen. Proceedings American Society for Testing Materials, Vol. XI (1911), p. 815. * Some Results Showing the Behavior of Rails under the Drop Test, and Proposed New Form of Standard Drop Testing-Machine. S. S. Martin. Proceedings Am. Soc. for Test. Materials, 1908, Vol. VIII. STRENGTH OF THE RAIL 289 is soft or hard. Recent work in Germany and France points to the conclusion that some form of impact test is found necessary to detect faults of structure that are not evidenced by the static test. Average specifications, which a majority of the railroads have in recent years used as a standard, contain the following clause as to drop test: One test shall be made on a piece of rail, not less than 4 feet, nor more than 6 feet, selected from each blow of steel. The test piece shall be taken from the top of the ingot. The rails shall be placed head upwards on the supports, and the various sections shall be subjected to the follow- ing impact tests under free falling weight: 70 to 79 pound rail, 18-foot drop. 80 to 89 pound rail, 20-foot drop. 90 to 100 pound rail, 22-foot drop. If any rail breaks, when subjected to the drop test, two additional tests may be made of other rails from the same blow of steel, also taken from the top of the ingot, and if either of these latter rails fail, all the rails of that blow which they represent will be rejected; but if both these additional test pieces meet the requirements, all the rails of the blow which they represent will be accepted. The drop-testing machine shall have a tup of 2000 pounds weight, the striking face of which shall have a radius of not more than 5 inches, and the test rail shall be placed head upward on solid supports 3 feet apart. The anvil block shall weigh at least 20,000 pounds, and the supports shall be part of or firmly secured to the anvil. The report of the drop test shall state the at- mospheric temperature at the time the test was made. These specifications, while used by the railroads, had to be modified ac- cording to the character of the drop-testing machines at the different mills. Thus, we find machines answering closely the following descriptions : 1. A drop-test machine consisting of some concrete and loose stone, supporting a number of 12 by 12 inch oak ties, 12 feet long, on which is placed an oak block 18 inches by 18 inches by 11 feet. On the oak block are two steel plates 1 by 18 inches by 7 feet, which become the bearings for the rail supports. These supports weigh 1300 pounds. 2. A drop-test machine consisting of a wooden foundation 4 feet deep and 10 by 10 feet, on which were placed two blooms, probably 8 by 10 inches by 10 feet. On the blooms are placed the rail supports. 3. A drop-test machine consisting of a concrete or stone foundation, on which rests a 20,000- pound anvil, to which the rail supports are securely fastened. Up to within the last few years no rail mill has been equipped with a drop- testing machine for rails that was built on thoroughly scientific principles, owing to the lack of proper foundations or proper anvil, as well as many other essential details. Further, no two rail mills had machines built on even comparatively the same lines. Consequently, any exact determination of the loss of energy of the falling weight which is dissipated by the machine would have had no general application, and the results obtained from testing rails in the drop- testing machines of any two mills were not comparable. 290 STEEL RAILS ' The Manufacturers' Committee, recognizing these defects, prepared speci- fications and plans of a proposed standard drop-testing machine that will give satisfactory and comparable results, and the Rail Committee of the American Railway Engineering Association has, with certain small modifications and additions, approved these plans and specifications. Specifications for Drop-Testing Machine (See Fig. 204.) 1. The machine shall be arranged to allow a 2000-pound tup to fall freely at least 25 feet on the center of a rail resting on supports that can be adjusted to spans varying from 3 feet to 4 feet 6 inches. 2. The anvil shall be a solid casting, weighing, with the attachments that move with it, 20,000 pounds. It shall be free to move vertically independently of the lead columns and shall be supported on 20 springs known as the standard " C " spring, without center coil, as employed by the Master Car Builders' Association (their figure 5614). This spring has a free length of 8 1 inches, an outside diameter oi 5ts inches, and is made from a bar having a diameter of 1^ inches. These springs are to be arranged in groups of five at each corner of the anvil and are to be held in place by hubs raised on the top of the base plate and by circular pockets on the under side of the anvil. Anvil to be guided in its vertical movement by removable finished wearing strips, these strips to be suitably attached to the finished edges of the column base. 3. The base plate shall be of cast iron or cast steel, 8 inches thick in the area covered by the anvil. It shall be firmly secured to the substructure by four bolts 2 inches in diameter. 4. The substructure shall consist of a timber grillage resting on a masonry foundation. The grillage shall project 9 inches beyond the ends of the base plate, and clear the columns at the side. It shall consist of one course of 12 inches by 12 inches sound oak or southern yellow pine, pref- erably creosoted, laid close and well bolted together. The masonry, preferably concrete, shall not be less than 5 feet deep below the grillage and be suitably supported on the subsoil. 5. The pedestals for supporting the test rail shall be substantial castings, and the surface of the anvil between these pedestals shall be formed to receive a wooden block to absorb shock under broken pieces. The rail supports shall be removable pieces of steel securely held in the pedestals having an upper cylindrical bearing surface with a radius of 5 inches. The pedestals shall be adjustable to spans, varying from 3 feet minimum to 4 feet 6 inches maximum between centers. They shall be securely held together and so fixed to the anvil as to insure that the center of span shall always coincide with the center between leads. 6. The leads shall be firmly connected to the base plate and well braced. They shall be long enough to provide the prescribed free fall of the tup. They shall be provided with a con- venient ladder and a plainly marked gauge, divided into one-foot intervals. The zero of this gauge shall be 5 $ inches above the top of the rail support, and the specified height of drop shall be measured from this zero, irrespective of the height of the rail being tested. One of the guides shall have a removable section, 6 feet long at the bottom, so that the tup or tripping block can be readily removed. 7. The tup shall weigh, with the accessories that drop with it, 2000 pounds. The striking die shall be steel having a cylindrical striking face with radius of 5 inches and a length of 12 inches. The guide grooves shall have finished surfaces. The tripping head shall allow a grip of the tongs that will release at the exact height for which the tripping device is set and that will be safe from accidental release while the test piece is being shifted. 8. The tongs and tripping device shall be arranged to release the tup automatically only; no manual releasing will be allowed. The tripping device shall be easily adjustable at one-foot intervals. Fia. 204. — Standard Drop Testing Machine, as adopted by Committee of Rail Manufacturers of the United States, April 8, 1908. Recommended by Committee on Rail of the American Railway Engineering Association at Meeting of June 26, 1908. Adopted by the Association, Vol. 10, Pt. 1, 1909, pp. 369-373, 375, 395, 396; Vol. 11, Pt. 1, 1910, pp. 240, 252, 562. Sellew." Steel Rails." STRENGTH OF THE RAIL 291 A diagram showing graphically the relation between results of tests as between the old and new methods, furnished by Mr. Thomas H. Johnson, is given in Fig. 205. These tests were made on rails of the same grade of steel, viz., carbon, about .50, and manganese, .90 to 1.00. All of the tests were made with a Fig. 205. — Diagram of Tests with Drop-Testing Machines of Old and New Design. (Johnson.) 2000-pound tup, with a radius of striking face 5 inches, and span between centers of supports 3 feet. Table LXXI gives the result of these tests. Since 1908 a number of machines of this design have been installed at various mills with satisfactory results. The introduction of a standard drop- testing machine has been of such benefit to the manufacturers and consumers of this country that the International Association for Testing Materials has pub- lished a description and cuts of the American Standard drop-testing machine in French, German, and English.* The seventh London Resolution of the Council was as follows : "That a standard drop-testing machine for rails be adopted in each country, as has already- been done in the United States, in order to make tests comparative." * Proceedings, Vol. 11, No. 4, May 20, 1911, p. 237. 292 STEEL RAILS If we consider what occurs in dealing the blow on the rail with the falling weight, it will be seen that the work utilized by the rail in order to take a cor- responding set is not the potential energy of the weight at the moment when the weight touches the bar. The energy of the falling weight serves to deform the rail, to compress the supports, the body of the drop weight, the anvil, and the ground upon which the anvil is placed. TABLE LXXI.— TESTS ON NEW AND OLD DROP-TESTING MACHINE OF P. R.R. AND P. S. RAIL SECTIONS (Am. Ry. Eng. Assn.) New Standard Machine. Old-Style Machine. Height of P. R.R. P. S. P. R.R. P. S. P. R.R. P. s. P. R.R. P. S. 85-Pound 85-Pound 100-Pound 100-Pound 85-Pound 85 Pound 100-Pound 100-Pound Set. Set. Set. Set. Set. Set. Set. Set. Feet. Inches. Inches. Inches. Inches. Inches. I iches. Inches. Inches. .5 .02 .02 .02 .02 .0 .0 1 .08 .08 08 .06 .031 .031 1.5 .16 .17 14 .15 .093 062 .062 031 2 .25 .22 19 .19 .125 093 .125 093 3 .38 .37 28 .25 .250 171 .218 109 4 .49 .47 40 .38 .343 250 .281 250 5 .60 .53 50 .45 .406 343 .375 312 6 .76 .66 64 .62 .513 468 .437 375 7 .88 .76 74 .70 .700 600 .650 375 8 .99 .90 86 .81 .800 700 .700 600 9 1.12 1.01 98 .90 .900 800 .750 700 10 1.20 1.13 1 06 1.02 1.000 850 .800 800 Breuil* has shown that for the same amount of actual work the bending curve of the impact test is the same as the slow-bending test, and Hattf has observed that there is little difference in the total elongation and unit rupture work whether the bar is ruptured in ten minutes or in from one to two one- hundredths of a second.J * Relation between the Effect of Stresses slowly applied and Stresses suddenly applied in the Case of Iron and Steel. P. Breuil. 1904. t Tensile Impact Tests of Metals. Hatt. Proceedings Am. Soc. for Test. Materials, 1904, Vol. IV. | As further evidence we may quote the following opinions (Report on Impact Tests of Metals. Official report by G. Charpy, Montlucon, International Association for Testing Materials, 5th Con- gress, Copenhagen, 1909. McGraw-Hill Book Company, New York) : Captain Duguet writes: " The effect (of the duration of the stress) is very marked, especially during the period of great deformations; that would in itself suffice to render any too detailed investigation of the phenomena illusory. But we must not exaggerate the importance of this point. The extreme deformations are, in the case of soft steel, submitted to bending, very sen- sibly the same, whether they be produced slowly by hydraulic pressure or by the impact of a tup." In his treatise on material testing, Professor Martens points out that, according to the experiments of Kick, the velocity of fall has only an insignificant influence on the magnitude of the deformation in impact bending tests. As regards tensile strength tests, Professor Martens concludes: " From the impact tension tests so far conducted in the Charlottenburg Laboratory, I have acquired the conviction that the deformations are produced exactly as by slow tension. STRENGTH OF THE RAIL 293 Fig. 206 shows the amount of energy dissipated in 90-pound A. R. A. type " B " Bessemer rails when tested in the drop-testing machine.* The weight of the tup was 2000 pounds and the distance between supports three feet in both the dynamic and static tests. The anvil in the drop test weighed 10 tons, spring supported. Calculating the work done on the rail in the static test from the load deflection diagram, and in the drop test from the height of drop and weight of tup, it would appear from the lower diagram of the figure that about two-thirds of the energy of the falling tup is utilized to deflect this rail. The difficulty of comparing the values of the stresses in impact tests with those which occur in static tests (i.e., where the momentum of the load does not factor) lies in the difficulty of accurately determining the value of the force acting between the hammer and the specimen in the former. Comparisons of the total work required to rupture a specimen, or to produce a given deflection, are comparatively simple. The manner in which impact stresses are related to so-called static stresses requires careful theoretical consideration before it can be clearly comprehended. The author is indebted to the work of Mr. H. D. Tiemann f for the following presentation of the subject. The rail tested by impact is in reality in the nature of a cushion between the two impacting bodies, namely, the tup A and the anvil B, and the anvil B must be of such proportions that its relative velocity v b to that of the com- mon center of gravity of itself and the tup, V, may be disregarded, as other- wise a correction must necessarily be made, which not only complicates the " subject, but on account of the nature of the foundation of the anvil is almost impossible to apply. In tension tests by means of several blows, we find often that the elongation was greater than in the slow-tension tests." M. Lebasteur (Annales des Ponts et Chaussees, 1890) had likewise arrived at the following conclusions : " 1. The elongations observed in the fracture of bars under high-drop impact tests are nearly identical with the elongations of similar bars under slow tension. "2. The appearances of the broken sections are absolutely the same in the two cases. "3. The total intensities of the blows necessary to break bars under high-drop impacts are proportional to the dynamic resistance to rupture (as determined from the area of the curve of slow tensile stress);" and further on M. Lebasteur added that "the dynamic resistance to rupture measures the strengths of metals equally well for dynamic as for static stresses." * Report, M. H. Wickhorst to Rail Committee of Am. Ry. Eng. & M. of W. Assn., Proceedings, Vol. 12, Part 2, p. 389-394. t The Theory of Impact and its Application to Testing Materials, Journal of the Franklin In- stitute, October and November, 1909. STEEL RAILS sannod avoi z z9 - \n en w S. CD zoj^ Qz Po \ \ A UJ O a. V J \ A ■a o2 g- Z .9 Q o o (SI — SNOJ. JLOOJ O W O 10 CM — ~ 133J dOHQ dO 1H9I3H STRENGTH OF THE RAIL 295 If we consider what occurs at impact, it is seen that at the beginning of contact a mutual repellant force F begins to come into play between A and B, which produces a change in the relative velocities (y a - V) and (v b - V), where v a = the velocity of A, v b = " " " B, V = " " " the mutual center of gravity of A and B along a line joining their respective centers of gravity. This force F, starting from at first contact and increasing to a maximum when both relative velocities of A and B are brought to 0, then when rebound begins again decreasing until it becomes at departure, is counterbalanced directly by the local compression of the material of both bodies at the point of contact. This force is made up of two parts, one being the elastic resistance of the body to compression or deformation, /, and the other of the force necessary to produce the local acceleration of the particles compressed, f x . F = f + f, At any instant F is exactly equal to the change in momentum produced by its action divided by the time required to produce this change : p m (v - vi) F= t-t, • t-, mdv d 2 s F --df = m di> = ma - m = mass, s = space, t = time, v = velocity a = acceleration. Consequently, if the time-velocity curve can be determined, the force F can be calculated for any instant. Let us examine first the relations between the various quantities of an impact test graphically, and then proceed to develop formulae of the time-space curve and of the interrelations of the values. Consider, first, a rail lying horizontally on the anvil B and supported freely at its ends, and let it be struck at the center by a falling tup A. For simplicity let us consider the rail as massless as well as weightless. Or more exactly, where 296 STEEL RAILS Take the velocities as relative to the anvil, as explained above, or assume the mass of the anvil so great that its motion may be taken as zero. Let the motion of the center of gravity of the tup A be plotted as in Fig. 207, with space as ordinates and time as abscissae. If the tup start at some point J, and fall freely the distance H before striking the rail, the curve JB will be a parab- ola, or if its velocity be uniform its motion would give the straight line JiB. Impact with the rail begins at B, and, assuming the rail as massless, the only resistance offered to the momentum of the tup will be the bending stress of the rail, which will be the force F. The motion curve then becomes 7 Fig. 207. — Time-deflection Curve, Massless Beam, within the Elastic Limit. (Journal of the Franklin Institute. — Tiemann.) BC. The resisting force, starting with at B, increases in proportion to the deflection of the rail until the maximum value is reached at C. (In this case, let the elastic limit of the rail be not exceeded.) It is this force F which overcomes the momentum of the tup A by producing a negative accelera- tion until the momentum is reduced to at C. Rebound then begins. If the rail is perfectly elastic, the force F continuing to act will restore exactly the same amount of momentum to A, and in the same manner, but in the opposite direction that it had at the beginning of contact. The curve will be CD. At D departure takes place (the rail being considered as massless). The total mutual repellent force F acting on the rail, between the tup A and the anvil B, is at any instant equal to d 2 S , dv A, where S is the space traversed by A and v is its velocity at the instant under STRENGTH OF THE RAIL 297 consideration. If S is in feet, t in seconds, and A = (weight in pounds -4- accel- eration of gravity in feet), then F is given in pounds, by the last formula. If the force of gravity is to be considered, as well as the initial velocity of A at impact, then this formula should be written: F-W a = ^A= d i t A, at 2 at where W a is the weight in pounds of the tup A. This could be avoided by having the tup move horizontally instead of falling vertically. Examining Fig. 207, it will be noted that the acceleration of the tup from J to B is equal to g and is produced by the uniform force W a . From B to D it is produced by the force W a — F and becomes negative as soon as the value of F begins to exceed W a . This is at the point of reverse curvature, since the acceleration cN dt 2 is zero, and evidently occurs at the point b or the deflection which would be produced by the static load W a . In horizontal motion the change would occur at contact, B. It should be remembered that while W a is a constant force, F is a variable, ranging from at B, to a maximum at C, and again to at D. Whenever dh dt 2 becomes a maximum the force F becomes a maximum, and this evidently occurs at the sharpest part of the curve, which in this particular case is at C. The value of F at any instant may, therefore, be determined from the curve F = ^ x A + W a . at 1 If the force F of the impulse becomes sufficient to cause complete failure of the specimen, the conditions are those shown in Fig. 208. The first part of the curve JB is the same as before. The velocity or momentum of the tup is, in this case, not entirely overcome by the resistance F of the rail, so that at failure the tup retains a portion of its velocity as indicated by the tangent line DE X . If the tup works vertically in free fall, instead of horizontally, then the curve DE is again a parabola of free fall. In this case the force F becomes a maximum at some point C, when the curvature is sharpest, and must be determined from the curve by d 2 s dt 2 ' since there is no means of calculating it mathematically. 298 STEEL RAILS The curve can be conveniently obtained by some mechanical device by means of which the falling tup makes a tracing on a uniformly revolving drum. When F is thus determined the maximum strength values may be calculated. To supplement the information furnished by the drop test engineers are turn- ing their attention to other means of testing the physical properties of the rail. Fig. 208. — Time-deflection Curve, Beam Stressed beyond the Elastic Limit (Journal of the Franklin Institute. — Tiemann.) * The Baltimore and Ohio Railroad Company, in connection with its inves- tigations on rail, has been making use of the scleroscope (Fig. 209), an instrument for determining the degree of hardness of metals. f The principle of the scleroscope (Greek sclero = hardness) consists of drop- ping a small plunger hammer from a fixed height onto the surface of the material whose hardness is to be measured. This hammer after striking, by no other force than its own weight, rebounds to variable heights, depending on the hardness or amount of resistance to penetration offered Fig. 209.— Scleroscope. (Am. Ry. Eng. Assn.) -by the metal tested. The rebound of the hammer is used to measure the hardness of the metal, and the scale shown on the glass tube is simply for * General Information Concerning the Scleroscope and its Use on the Baltimore and Ohio Rail- road. A. W. Thompson. Proceedings, Am. Ry. Eng. & M. of W. Assn., 1910, Vol. 11, Part I. t See also The Scleroscope, Albert F. Shore, p. 490, Proceedings American Society for Testing Materials, Vol. X, 1910. STRENGTH OF THE RAIL 299 comparative purposes and has no direct numerical value. This scale has 140 graduations, and a test of very hard steel has resulted in a rebound to the point marked 110, while soft brass results in a rebound to the point marked 12, and lead is about 2 per cent of hard steel. Figs. 210, 211, and 212 present examples of tests. The numbers in these figures indicate the degrees of hardness. Fig. 210 is an A. R. A. section of open-hearth rail, as rolled by the Bethle- hem Steel Company, and is a new section which has not been in the track. It will be noted that the hardness on the top of the head of the rail is practically Fig. 210. — Scleroscope Tests on Open Hearth Rail (New.) (Am. Ry. Eng. Assn.) Fig. 211. — Scleroscope Tests on Bessemer Rail. (Am. Ry. Eng. Assn.) the same as the steel in the section of the rail just below the surface. The center of the head appears to be the hardest, as well as a line through the center of the web and base. The upper corners of the head are comparatively soft, the ends of the base, however, being very much softer than any of the rest of the rail. Fig. 211 is a section of a Bessemer rail rolled at Buffalo in 1908. It is a crop from the top end of a top rail. Although the specimen was from the top of the ingot, there is a difference of but three points in the. readings throughout the head. The section, where polished and etched, showed rather dimly marked segregation. The head and base when planed into and etched showed some dark streaks in the head and light streaks and fissures in the base. The top of the head for finch depth was sound. The experimenter says: " The section as a whole is more uniform than is usually to be found in top, middle, or bottom rail of a Bessemer ' ingot.' " 300 STEEL RAILS ^ 111. Fig. 212 shows the comparative hardness on different lines on experimental titanium rails. This test indicates a skin of soft metal across the top of the head, but as soon as this is penetrated the hardness is reached, which compares favor- ably with any part of the whole section. * Experiments were made at the laboratories of McGill University on the value of the indentation test for steel rails in regard to essential qualities desired in service. The study of this method of testing was suggested by tests made on a large number of rail sections by the Chief Engineer of the Canadian Pacific Railway, a spherical punch .75 inch in diameter Fig. 212.— Scleroscope Tests on New Titanium being used, with a load of 100,000 pounds Ran. (Am. Ry. En g . Assn.) applied by an Emery testing machine for 10 seconds after commencing the load, and the indentation was measured by an instrument reading to yoVo i ncn - The tests, conducted by Mr. Dutcher, were on a set of bars of 2.5 by .75- inch section containing known percentages of carbon, which were verified by tests, and varied between .11 per cent and .96 per cent. The punches used (in addition to the foregoing) were a 60° cone, a 90° cone, and a paraboloid. The term " hardness factor " applied to the results was obtained by divid- ing the projected area of the indentation on the surface of the specimen into the load applied. It was found that the yield point (as determined by tensile tests) varies directly as the hardness factor. The percentage elongation curve is also fairly straight between 200,000 pounds hardness factor (.10 per cent carbon steel) and 450,000 pounds hardness factor (about .70 per cent carbon steel); and the percentage of carbon varies directly with the hardness factor up to about .90 per cent. f There have been several methods proposed to test the hardness of the metal by ball-pressure tests. In the Brinell test J a hard ball of steel is forced * Transactions of the Canadian Society of Civil Engineers, Dutcher, Vol. XXI, pp. 47-88. t Hardness Tests. Official report by Dr. techn. P. Ludwik, of Vienna. International Associa- tion for Testing Materials, 5th Congress, Copenhagen, 1909. McGraw-Hill Book Company, New York, also various technical papers on Hardness Tests. Proceedings, American Society for Testing Materials, Vol. XI, 1911, pp. 707-743. % Compare P. Ludwik, " TJber Hartebestimmung mittelst der Brinnellschen Kugeldruckprobe und verwandter Eindruckverfahren," " Zeitschrift des osterr. Ingenieur und Architekten-Vereines," 1907, Nr. 11 und 12 (Nr. 12, p. 205, extensive literature references). STRENGTH OF THE RAIL 301 by quiet pressure into the material to be examined ; the diameter of the spherical impression is determined, as a rule, with the aid of a special microscope, and the area of the cavity is calculated. The quotient of pressure (in kilograms) by the area (in millimeters 2 ) is Brinell's hardness number H. The cone-pressure test marks a transition from the ball-pressure methods to scratch methods. It is the outcome of efforts to simplify the Brinell test, with the further object of making the hardness number independent of the load and of the dimensions of the impression. In the Amsler-Laffon instrument (Fig. 213) a cylindrical steel center punch, plane above, ground to a right-angled cone below, is vertically mounted in a casing of bronze, in which it is free to turn ; it is balanced by a lateral spring. The displacement of the cone (with regard to the casing) is transferred to a pointer by an elastic threaded bush- ing and a toothed wheel; the pointer allows of easily reading depths up to 5 millimeters within .01 millimeter. The pointer is accurately adjusted by turn- ing it with the aid of the milled edge of the bushing, in case the top of the specimen should not be perfectly plane. The cone can easily be exchanged and be reground. The whole instrument & Fig. 213. — Amsler-Laffon Instrument for Weighs .7 kilogram (1| pounds), and Measuring Hardness. its height, from the upper pressure plate to the surface of the specimen, is about 10 centimeters (4 inches). The question, whether the hardness numbers of a material, obtained by these methods, admit of any general conclusions respecting the strength of the material, and in particular the yield point and the tensile strength, is of high practical interest. A direct constant relation between yield point and tensile strength on the one side, and hardness on the other, can not exist, since that relation would, among other factors, depend upon the shape of the impression and of the stress- strain diagram. This admission does not, however, at all exclude the possibility of deducing from the hardness number, with the aid of a coefficient which will only hold 302 STEEL RAILS good between certain known limits, the yield point and the tensile strength with an approximation which will frequently be sufficient for practical purposes.* f Permanent-way materials have been tested by Ludwik's cone-pressure method with two objects: to inquire into the suitability of the method for practi- cal purposes, and to ascertain the relation between the cone-pressure hardness and the tensile strength. The experiments have been conducted in connection with the acceptance tests of the materials supplied to the J. R. Austrian State Railways during the year 1908, in the Trzynietz Iron Works of the Osterr. Berg- und Hiittenwerks- Gesellschaft with the aid of an Amsler-Laffon cone-pressure hardness tester J on a Mohr and Federhaff testing machine. The material experimented upon comprised rails, railway ties, splices, and steel crossings. The specimens were not prepared in any way apart from being cleaned ; an exception was made in the case of the steel points, in which the outer skin con- taining coarse impurities had to be removed completely. The following are the chief results : The ratio of tensile strength to cone-pressure hardness had a mean value of about .335, the range of deviation being ±6 per cent. The lowest tensile strength of 65 kg./mm. 2 (42 tons per square inch), ad- missible for rails, corresponded to a cone-pressure hardness of about 190. The tensile strengths of ties and of smaller parts for the permanent way varied between 39 and 47 kg./mm. 2 (24.75 and 29.8 tons per square inch) and the corresponding hardness numbers between 117 and 144. The range of variation is hence approximately the same for the tensile strengths as for the hardness numbers. Other methods of testing hardness have been used. The sclerometer of Turner makes use of a diamond point which is drawn across the surface to be measured. The weight required upon this point to make a barely visible scratch determines the degree of hardness. This machine is sometimes used with a series of standard weights and the width of a scratch made by one of these * For instance, the Prussian Railway Department stipulates for rails of a minimum tensile strength of 60 kg. /mm. 2 (38 tons per square inch), with balls of 19 mm. (finch) diameter and 50 tons loads, impres- sion depths of from 3.5 to 5.5 mm. ; for rails of a minimum tensile strength of 70 kg./mm. 2 (44.5 tons per square inch), impression depths ranging from 3 to 5 mm. Breaking tests and ball tests have to be made in equal numbers. (Zentralblatt der Bauver-waltung, 1908, No. 77, p. 520.) t The Cone-pressure Test for Determining the Hardness of Permanent-way Materials, by Dr. techn. August Gefener, Vienna. International Association for Testing Materials, 5th Congress, Copen- hagen, 1909. McGraw-Hill Book Company, New York. t Compare P. Ludwik, " Die Kegelprobe, ein neues Verfahren zur Hartebestimmung von Materi- alien." Berlin, 1908, Julius Springer. STRENGTH OF THE RAIL 303 measured under a microscope. The Keep test employs an instrument which drills into the specimen and gives a measure of the work required to cut out the metal, thus testing not only the surface, but also the interior. The Jaggar instrument is similar, but uses a small diamond drill in connection with a micro- scope. Resistance to penetration was long tested by the United States Ordnance Department by means of a weighted punch, and a somewhat similar result was obtained by means of a series of needles of graded hardness, which were tried in succession until one was found that would scratch the material under test. While many inconsistencies are found in hardness tests, it is generally con- ceded that the test affords an excellent comparison of metals of the same general composition and treatment, and the results thus far seem to justify the expecta- tion that it will in many cases be possible and advantageous to employ this method in the testing of rails in place of the more elaborate and expensive tensile strength tests which some foreign engineers require in addition to the drop test. The magnetic laboratory of the Bureau of Standards is carrying on an investi- gation on the relation between the magnetic and mechanical properties of steels. The reluctance, or the ratio of the magnetizing force to the magnetic induction, of a rail is greatly affected by changes in homogeneity, such as may be caused by segre- gation, blowholes, or strains due to any cause whatever. By means of the mag- netic data taken along the length of a rail it is possible to detect the presence of these defects. Special machines have been devised from time to time for testing different properties of the rail, as the machine for testing rail wear illustrated in Fig. 151. * The Pennsylvania Steel Company has a machine (Fig. 214) for testing rail wear which enables specimens of rails to undergo wear similar to that im- posed upon them by every description of traffic, but in a much shorter time than if tried in the ordinary road. The rails are fixed to a 20-foot diameter circular frame, three specimens being included in the circle. Two standard 33-incl wheels having independent axles fixed at each end of a heavy casting, which is pivoted at the center of the circle, run upon the rails at speeds up to 85 revolu tions per minute, equivalent to a train speed of about 60 miles per hour, ^hert are devices by which, through means of springs, pressure is exerted vertically and also centrifugally on the rail, so that the action of the load can be imitated, as well as that of its lateral pressure on the rail, and the effect produced by continu- ous wear on the rails of different manufacture and composition can be estimated in a comparatively short time. * Railway and Engineering Review, Chicago, 1908, Vol. XI VIII, p. 868. 304 STEEL RAILS Fig. 214. — Machine for Testing Rail Wear at Pennsylvania Steel Company. Extensive tests have been made of the tensile strength of the steel in the rail by Mr. M. H. Wickhorst, Engineer of Tests of the Rail Committee of the American Railway Engineering Association, covering rails rolled at Gary and at the Lackawanna Steel Company. The rails from the Gary works were open-hearth steel and 100-pound, A. R. A., Type B section. The ingots furnished six rails, which were lettered A, B, C, D, E, F, the A rails coming from the top of the ingot, etc. Tensile tests were made of pieces |-inch diameter by 2-inch gauge length, cut from near the top end of each rail, as shown in Fig. 215. Five locations in - Diagram of Round Test Pieces; Tensile Tests on Rail steel. (Wickhorst.) the sections were selected as STRENGTH OF THE RAIL 305 shown, and tests were made in duplicate, the bar being cut sufficiently long to make two test pieces. The yield point was determined by means of a Capp's multiplying divider, which method gives a result somewhat above the elastic limit, but which, however, is probably sufficiently definite to make it desirable to determine it, and is not subject to the irregularities of the yield point as determined by the drop of the beam of the test machine, or even by ordinary dividers. The test pieces were very close to J-inch diameter at the center, but toward the ends of the gauge length most of them were from .002 to .004 inch larger in diameter. This would tend to make the elongation less than if the diameter were perfectly uniform. The results of the tensile tests are shown in Table LXXII. The duplicates agree well with each other except in a few cases where the test pieces broke " short " as follows: One sample from base of the A rail, one sample from the interior of the head of the B rail, and one sample from the corner of the head of the C rail. One sample from the web of the A rail should probably also be classed here. The duplicates from the lower rails of the ingot agree particularly well, indicating a freedom from local irregularities. The ratio of the yield point to the tensile strength averages about 51 per cent, and most specimens differ but little from this figure. A comparison of the tensile strength is interesting. Table LXXIII shows the tensile strength of the sample in each pair that gave the greatest ductility. The b samples from the interior of the head and the c sample from the web represent what was originally the interior of the ingot, and in the A rail these samples show strengths much higher than the samples from the other parts of the section representing what was the outer part of the ingot. This is also true of the B rail, but to a less extent, and also of the C rail to a slight extent. As we continue down the ingot, however, conditions are reversed, and we find in the D rail a little lower strength in the samples from the interior than in the samples representing what was the outer portion of the ingot. This difference is greater in the E rail and greatest in the F rail. The a sample from the corner of the head and the d sample from the flange would be metal of similar chemistry, but the flange has a considerably lower finishing temperature and is also reduced differently. Table LXXIV compares results from these two places. The d sample from the flange of the A rail is abnormal, with a low strength and high ductility, being evidently taken at a point of negative segregation of carbon; but, except for this sample, the d samples from the flange show a little 306 STEEL RAILS TABLE LXXIL — TESTS ON STRENGTH OF RAIL STEEL Tensile Tests on Open Hearth Rail Steel from Gary (Wickhorst) Tensile Strength. a-head, corner . . . 6-head, interior. c-web d-flange e-base a-head, corner. . . 6-head, interior. . a-head, corner. . . 6-head, interior. . c-web d-flange e-base a-head, corner . . . 6-head, interior . . c-web d-flange e-base a-head, corner. . . 6-head, interior. . c-web d-flange . : 2-base j-head, corner. . . 6-head, interior. . c-web d-flange Pounds per Square 63,930 61,640 69,510 70,020 "73,060 ' 56,820 63,420 65,690 66,970 68,220 70,310 70,010 66,970 65,690 64,940 63,930 67,710 65,690 66,970 69,230 66,970 66,230 66,490 67,480 64,170 64,170 67,990 68,720 64,940 65,930 66,930 66,970 70,020 70,460 65,690 69,290 66,740 "63,920 " 64,180 64,940 69,510 65,210 63,420 60,900 66,500 64,680 64,180 70,020 67,710 63,670 68,950 124,800 125,800 134,400 133,900 134,900 141,000 121,700 123,300 109,600 120,200 128,800 128,300 135,900 137,000 137,000 132,900 129,800 129,400 126,800 130,900 132,900 133,400 133,900 133,900 132,900 133,400 128,300 128,800 132,400 130,900 129,300 128,300 130,800 . 131,900 133,900 134,400 130,900 132,400 127,900 125,300 124,800 124,300 128,900 128,900 131,800 132,400 129,800 130,400 128,400 128,300 120,800 123,700 125,300 125,800 132,400 131,900 127,300 128,300 11.5 12.5 12.5 10.5 13 11.5 12.5 STRENGTH OF THE RAIL TABLE LXXIII.— TESTS ON STRENGTH OF RAIL STEEL Comparison of Strength in Different Parts of Open Hearth Rails from Gary (Wickhorst) 307 Rail. a-Head, Corner. 6-Head, Interior. c-Web. d-Flange. e-Base. A B 124,800 128,800 130,900 132,400 127,900 128,300 133,900 135,900 133,400 128,300 124,300 120,800 141,000 137,000 133,900 131,900 128,900 125,300 121,700 129,800 133,400 133,900 131,800 131,900 120,200 129,400 128,800 132,400 129,800 128,300 C D E F Average 128,800 129,400 133,000 130,400 128,200 TABLE LXXIV. — TESTS ON STRENGTH OF RAIL STEEL Comparison of Strength and Ductility of Steel taken from the Corner of the Head and Flange of Open Hearth Rails (Wickhorst) Rail. Tensile Strength pounds per Square Inch. Elongation in 2 Inches. Reduction of Area. « d a d « d A B 124,800 128,800 130,900 132,400 127,900 128,300 121,700 129,800 133,400 133,900 131,800 131,900 Per cent. 10 11.5 11.5 12 11 12 14 12 12.5 13 12 12.5 15 20 22 19 19 20 Per cent. 26 23 C D E F 27 28 26 21 Average B to F . . 129,700 132,200 11.6 12.4 20 25 higher strength and also a little greater ductility. As the difference in the work of rolling is perhaps sufficient to account for this, the conclusion seems to be that the difference in rolling temperature has not resulted in any important difference in the tensile properties. The b sample from the interior of the head and the c sample from the web would be of similar chemistry, as representing the interior of the ingot, but the web is thinner and gets more work in rolling and probably is finished at a lower temperature. A comparison of these two locations is shown in Table LXXV. TABLE LXXV. — TESTS ON STRENGTH ON RAIL STEEL Comparison of Strength and Ductility of Steel taken from the Interior of the Head and Web of Open Hearth Rails (Wickhorst) Rail. Tensile Strength Pounds per Square Inch. Elongation in 2 Inches. Reductio r of Area. b • 5 • 6 « A 133,900 135,900 133,400 128,300 124,300 120,800 141.000 137,Q0O 133,900 131,900 128,900 125,300 Per cent. 9 9 10 11 11 12 Per cent. 9 11 11.5 11.5 12.5 13 Per cent. 16 16 17 21 21 22 Per cent. 10 B 19 c 21 D 23 E 25 F 25 Average B to F . . 128,500 131,400 10.6 11.9 19.4 22.6 308 STEEL RAILS In the A rail it is probable that the carbon is higher in the web sample than in the head sample, but in the other rails there probably are no great differences, and the averages shown above are of the B to F rails inclusive. The tensile strength decreases as we go down the ingot and the ductility increases. The web samples, as compared with the head samples, show a little greater strength, an average of 131,400 pounds, as against 128,500 pounds, and also a little greater ductility, an average elongation of 11.9 per cent, as against 10.6 per cent, and a reduction of area of 22.6 per cent, as against 19.4 per cent. This difference, it would seem, is probably due to the increased work in rolling that the web gets. It is also interest- ing to note that the top rails show as good ductility in the head samples as the lower rails, allow- ing, of course, for the difference in tensile strength, which would make about 3 per cent decrease in elongation for an increase in tensile strength of 10,000 pounds. The tensile tests on the rail steel from the Lackawanna mill were from titanium Bessemer rails, 90-pound, A. R. A., Type B. It was planned to make ten- sile tests of pieces from near the top ends of each rail by cutting Fig. 216. — Test Pieces 16 inches long. Diagram of Flat five flat pieces f by 1 \ by 16 inches Test Pieces. Tensile Tests on Rail Steel. (Wickhorst.) f rom ^^ ra ^ ag s h own i n Fig. 216. The test pieces were cut in this manner from the A and D rails, but it soon appeared that the time required to prepare the pieces in this manner would cause considerable delays, and then, too, the surfaces are apt to be finished in a condition unsatisfactory for test. The plan was then changed so as to obtain pieces \ inch in diameter and 2-inch gauge length, as shown by Fig. 215. The pieces from the B and C rails were prepared in this manner. The results of the tensile tests are shown in Table LXXVI. Care must be taken not to compare the results of the flat test pieces with those from the round test pieces, except, perhaps, as regards the tensile strength, although even here the shape of the test piece would make some difference. STRENGTH OF THE RAIL 309 TABLE LXXVI.— TESTS ON STRENGTH OF RAIL STEEL Tensile Tests on Titanium Bessemer Rail Steel from Lackawanna (Wickhorst) a-head . . 6-head . . c-web . . . rf-fiange. e-base . . a-head. . 6-head . . c-web . . . d-flange e-base . . a-head . . 6-head. . c-web . . . d-flange . e-base. . a-head . . 6-head . . c-web . . d-flange . e-base. . Tens: .■ Strom; I h Per Square Inc 103,400 111,100 109,200 103,300 105,000 111,700 122,900 116,200 110,700 111,600 109,100 112,100 112,300 109,600 112,400 109,800 106,800 104,700 108,600 110,000 14.5 ' 11.7 ' 13.7 ' 19.0 ' 14.0 ' 17.5 ' 19.0 ' 18.0 ' 20.0 ' 16.0 ' 21.0 ' 20.0 ' 19.5 ' 12.5 10.0 ' 13.7 ' 10.0 ' 9.5 ' The following is a re- cord of tensile tests made by Waterhouse* on 100- pound A. S. C. E. rail taken from stock. The steel was made by the acid Bessemer process and the ingots rolled without reheating. From this rail two adjacent pieces 8| inches long were cut with a slow-speed cold saw, and from these pieces tensile- test bars were machined in the positions shown in Fig. 217. The results of the tensile tests are given in the following table, the figures being the average of those obtained from the duplicate pieces: * Examination of 100-pound Rails, p. 478. Fig. 217. — Location and Numbers of Test Pieces used in Waterhouse's Tests. (Railroad Age Gazette.) G. B. Waterhouse. Railroad Age Gazette, July 10, 1908, 310 STEEL RAILS TABLE LXXVIL— TESTS ON STRENGTH OF RAIL STEEL Tensile Tests on Bessemer Rail Steel (Waterhouse) Elastic Limit. Ultimate Stress. Elongation in 2 Inches. Reduction of 1 Pounds. 52,200 52,200 54,460 55,000 53,100 53,820 51,740 53,340 Pounds. 108,400 109,850 110,750 110,150 110,300 110,400 109,850 111,300 Per cent. 16.75 16.25 18.50 18.50 18.25 18.00 18.25 17.00 Per cent. 29.9 28.4 33.2 28.6 29.4 31.0 35.4 36.4 2 . 3 4 5 6 7 8 Table LXXVIII shows the chemical composition of the rails tested in the three tests just mentioned. TABLE LXXVIII.— CHEMICAL COMPOSITION OF RAIL STEEL IN TENSILE TESTS OF WICKHORST AND WATERHOUSE Carbon Silicon Manganese . . Sulphur Phosphorus . . Copper Per cent. 0.72 0.20 0.72 0.036 0.036 Per cent. 0.51 0.147 0.77 0.078 0.089 0.185 28. The Strength of the Rail and Proper Weight for Various Conditions of Loading In determining the proper stress to use for the rail, careful consideration must be given to the exact meaning of the terms by which the strength of the steel is shown. * The elastic limit or yield point may be properly called the limit of pro- portionality of stress to deformation, or more briefly, the limit of proportion- ality. The limit of proportionality is sometimes called the " true " elastic limit, and is frequently regarded as a measure of the load-carrying capacity of a member or structure. The absolute value of this limit cannot, in general, be determined even by the most careful measurements of deformation and load. It has been the experience of experimenters that any additional refinement of measurements in stress-deformation tests results in the detection of the limit of proportionality * Proceedings American Society for Testing Materials, 1910, Vol. X, pp. 243, 244. Moore. STRENGTH OF THE RAIL 311 at a stress lower than that determined by the less refined methods of measure- ment. Perhaps the thermo-electric apparatus used by Turner * and Rasch f for measuring deformation is the most delicate yet employed, and both of these experimenters showed the existence of a limit of proportionality at stresses far lower than those determined by extensometer measurements as ordinarily made. Members and structures become more and more nearly perfectly elastic if subjected to repeated stresses in the same direction, even if these stresses are so far beyond the limit of proportionality that there is a small but well-defined per- manent set upon release of the load. Fig. 218 shows the result of loading a beam several times to a stress well beyond the elastic limit. The first load applied to the beam produced considerable permanent set, and during the application and release of load considerable energy was lost, presumably in heat. This energy is shown by the shaded area to the left of the figure. During the second cycle of loading and release much less energy was lost, as shown by the central shaded area; and during the third cycle the beam behaved as if almost perfectly elastic. It should be noted that the above results would not be obtained if the direction of the load were reversed. The ultimate strength, or maximum capacity for resisting stress, has a ratio to the maximum stress due to the working load, which, although less in metal than in wooden or stone structures, is, nevertheless, made of considerable magnitude in many cases. It is much greater under moving than under steady " dead " loads, and varies with the character of the material used. For machinery it is usually 6 or 8; for structures erected by the civil engineer, from 5 to 6.| In general, parts of structures are so proportioned as to carry their loads without risk of exceeding their elastic limits; and in such cases the factor of safety should probably always be referred to the elastic limit. * Thermo Electric Measurements of Stress, Transactions American Society of Civil Engineers, Vol. XXVIII, January, 1902, p. 27. t Proceedings International Association for Testing Materials, No. 11, August 4, 1909, Article VII. t Iron and Steel, Materials of Engineering, Thurston, 1909, p. 340. One Division = 0.1 in. Deflection Fig. 218. — Effect of Repeated Loads on Beams. (Am. Soc. for Testing Materials — Moore.) 312 STEEL RAILS The elastic limit is made the basis of estimates by nearly all French engineers, while the ultimate strength is taken by German engineers, using a factor of safety of larger magnitude. British and American engineers usually base all calculations on the ultimate strength, although the former system is extending in general practice, and the limit of working load is made to fall well within the limit of elasticity. The general practice at the present time, for railway and highway bridges, is to use a unit strain of about one-half the elastic limit of the material. This factor is considered correct in places where the load assumed is an absolute maximum, as, for instance, where it consists of a definitely determined dead load only. In the rail the maximum stress acts during a very short space of time and its effect is not the same as the same load applied for a longer period. It is possible to apply a much greater stress than the elastic limit of the metal, pro- vided the stress be applied very quickly and then released. The excellent service given by some of the rails of lighter section, exposed to heavy wheel loads, gives evidence that a limited number of excessive stresses in the rail will not cause injury when applied for the small fraction of a second, as is the case of the stress caused by the wheel load. An extreme fiber stress of 20,000 pounds per square inch as applied to the base of the rail probably represents a satisfactory mean between the danger, on the one hand, of not providing a sufficient margin of safety for the unknown quantities of the problem and the liability, on the other hand, of taking too great a factor of safety, and thus designing an uneconomical structure. The following remarks of Professor Unwin are pertinent to this question : " If an engineer builds a structure which breaks, that is a mischief, but one of a limited and isolated kind, and the accident itself forces him to avoid a repetition of the blunder. But an engineer who from deficiency of scientific knowledge builds structures which don't break down, but which stand, and in which the material is clumsily wasted, commits blunders of a most insidious kind." Any consideration of the strength of the rail should take account not only of the stresses in the rail itself and the ability of the material of which it is com- posed to resist them, but a proper proportion must be made of the rail in order that it may distribute the wheel load to the ties in such a manner as not to over- strain any part of the track structure. The fact that a rail will not break should not be the determining factor in its selection, if, on account of lack of stiffness, it will allow too great a proportion of the load to come on a tie. The damaging effects of overloading the track, while much less apparent than the results attending the use of too great loads in other engineering struc- tures, are, nevertheless, of very real importance, and the lack of proper appre- ciation of the fundamental principles underlying its design has brought about STRENGTH OF THE RAIL 313 conditions requiring excessive maintenance charges to keep the track in proper condition. As the real function of the heavier rails is to distribute the wheel load and prevent too great a concentration of pressure on the track substructure, we have two limiting conditions to consider: First, the rail should be stiff enough to enable it to transfer the load in such a manner as not to exceed the maximum bearing power of the track substructure, and second, the safe working stress of the metal in the rail must not be exceeded. Before investigating the proper weight of rail to use with any track struc- ture, the weight and types of the locomotives and cars to be run over it should be considered, and the maximum wheel pressures ascertained for each type. The bearing power of the roadway or subgrade should next be examined. The influence of the character of the roadway is well shown by the follow- ing case reported by Mr. A. G. Wells, General Manager of the Atchison, Topeka and Santa Fe:* " From Seligman to Barstow our track is laid with eighty-five-pound rails; the density of the traffic is practically the same over every foot of it. Between Yucca and Barstow, a distance of 227 miles, the subgrade is sandy, porous, and well drained; between Yucca and Seligman, a distance of 91 miles, the subgrade is largely clay, of a kind that holds water. From November, 1907, to October, 1908, we had eighty-three rail breakages on the territory first named, or a per- centage of .001; on the other stretch we had in the same period seventy-two breakages, the per- centage being .0025, or, in other words, where the subgrade was dense and more or less clay, the s per mile were two and one-half times greater than where the subgrade was sandy." The bearing power of the subgrade is such an important factor in pro- portioning the track that it will prove profitable to examine what takes place when the soil is subjected to pressure.! As in any structure, good judgment must enter into the design; the formulas which will be demonstrated must be used as guides only. These formulas will depend upon the angle of repose of a homogeneous granular mass. For ordinary earths for which the angles of repose are known, the results obtained by the use of the formulas will compare very favorably with those obtained from examples of the best practice. When the angle of repose is not known it should be determined by test.f * Railroad Age Gazette, April 9, 1909. f The following discussion is based upon Retaining Walls for Earth, Howe, New York, 1896. t This can conveniently be done by measuring the force required to cause slipping of two por- tions of the earth past each other when subjected to a known pressure, and = angle of repose. s = force required to cause slipping. p = pressure on earth. 314 STEEL RAILS Earth which has an angle of repose of at least 27 degrees may be considered as firm. From Table LXXIX it is seen that sand, gravel, and damp clay are classed as firm soils; however, these may become so saturated with water that their angles of repose will become considerably less than 27 degrees, hence precaution must be taken against too much water by draining the ground in the immediate vicinity of the roadbed. Particular care must be taken in the case of clay, or sand which will become a kind of quicksand when saturated with water. The water which destroys the bearing power of such soils may come from below by capillary attraction,* and the drainage should be carried to a depth sufficient to prevent this. Semi-fluid soils, such as quicksand, alluvium, etc., should be removed where practicable or the foundation carried to a lower stratum. TABLE LXXIX. — ANGLES AND COEFFICIENTS OF FRICTION (Rankine's Applied Mechanics.) tan*. . sh Earth on earth Earth on earth, dry sand, clay, and Tilxed earth. . . 0.25 to 1.0 0.38 to 0.75 1.0 0.31 0.81 Degrees. 14 to 45 21 to 37 45 17 39 to 48 4 to 1 2.63 to 1.33 1 Earth on earth, wet clay Earth on earth, shingle, and gravel 3.23 1.23 toO. 9 Let Fig. 219 represent a section of the track, and BALLAST WW 7 r 1 S7777777777777777T. SUBGRADE Fig. 219. — Resistance of Sub-grade to = the depth of ballast; WVM//////MI* e of the Track. p = the maximum supporting power per square foot of thesubgrade; p l the pressure exerted on subgrade midway between ties; 7 = the weight of one cubic foot of ballast; (f> = the angle of repose of subgrade; xj equals the vertical intensity of the pressure caused by the weight of the * Movements of Ground Water, by F. H. King and C. S. Slichter, Government Printing Office, Washington, D. C, 1899, p. 65. STRENGTH OF THE RAIL 315 ballast on the subgrade midway between the ties. This pressure is augmented by the pressure transmitted from the tie, and, while this is much less between the ties than immediately underneath a tie, it is, nevertheless, an important factor in strengthening the surface of the roadbed. If we assume this extra pressure on the roadbed midway between the ties to equal in amount yx we will probably be on the safe side and can then write Pi = 2 yx* Now when the ballast is about to sink v 1 + sin 1 — sin 6 - = =-^ — ; — - or q = v \ : — - • q 1 - sin (j) 1 + sm But when the roadbed under the tie is on the point of sinking, the part of the roadbed between the ties must be on the point of rising, or (I _ 1 + sin 4> Vx ~ 1 - sin 4> ' and the supporting power of the subgrade, or P=Pi For convenience the values > in Table LXXXI. \ 1 + sin 4>\ 1 — sin S 1 + sin 4> ) 2 1 — sin S 1 - sin 4>) are given in Table LXXX and for TABLE LXXX l+sin<* >) sin<£ ) Values of (How 1 ( 1 + sin 4, 1 \ * j l + sin*)* \ 1 - sin <)> i 1 1 - gin 4> 1 ' 1.00 23 5.21 5 1.42 24 5.62 6 1.52 25 6.07 7 1.63 26 6.56 8 1.75 27 7.09 9 1.88 28 7.67 10 2.02 29 8.30 11 2.16 30 9.00 12 2.32 31 9.76 13 2.50 32 10.59 14 2.68 33 11.50 15 2.88 34 12.51 16 3.10 35 13.62 17 3.33 36 14.84 18 3.59 37 16.18 19 3.86 38 17.67 20 4.22 39 19.64 21 4.48 40 21.16 22 4.83 * This apparently would be a safe assumption for a depth of gravel ballast under the tie of 18 inches and 12 inches of stone. For a less depth of ballast the pressure would be less and for a greater depth the pressure would increase, the increase being more rapid in the case of the stone than of the gravel ballast. 316 STEEL RAILS TABLE LXXXI. —VALUES OF 7 Name of Ballast. Average Weight, in Pounds per Cubic Foot. 90 to 106 90 to 106 118 to 129 90 to 108 Stone, crushed Considering first the weight of rail which will give a proper distribution of pressure to the track, we may adopt a tentative system of classification for the track structure based upon the kind of tie, tie spacing, depth and kind of ballast, and character of subgrade. As previously noted, a tie spacing of 20 inches with 18 inches of gravel or 12 inches of stone under the tie, resting on a roadbed capable of bearing 1.5 tons per square foot, will sustain safely a load of 700 pounds per linear inch under each rail. This grade of track we will desig- nate as class A. Class B and C will represent weaker structures, which may be brought about by a departure in any or all of the elements from those found in class A track. A track would be graded as class B if it was capable of carrying only 600 pounds per linear inch under each rail. This might occur in several ways. A tie spacing of 22 inches, but with all the other elements of class A track, would diminish the strength of the structure on account of greater concentration of the load on each tie and on the subgrade; similarly, a lesser depth of ballast would affect the load on the subgrade. Evidently, a track with all the other elements of class A, but resting on a soil having a lower bearing power, would offer less resistance to the action of the wheel load. Table LXXXII presents descriptions of different kinds of track in each of these classes. It will be observed that the limiting factors may be considered as being the supporting power of the roadbed and the bearing of the rail on the tie. The bending stress in the tie and the bearing of the tie on the ballast are of secondary importance. Considering first the bearing under the rail. This is evidently a function of the tie spacing and kind of wood of which the tie is made. For class A track, capable of supporting 700 pounds per linear inch under each rail, a tie spacing of 20 inches would give a load on each tie under the rail bearing of 14,000 pounds. This is about the limit of the strength of the woods shown for class A track, and therefore excludes the use of weaker woods or greater tie spacing for this class of track. STRENGTH OF THE RAIL 317 In class B track, having a supporting power of 600 pounds per linear inch under each rail, the tie spacing may be increased to 22 inches for the woods allowed in class A track. It is doubtful whether the group of woods shown in the table under class C track should be used for class B track even with a tie spacing of 20 inches. TABLE LXXXII. — CLASSES OF TRACK Class of Tie. Ballast, Depth under Tie. Subgrade Bearing Power. Bearing Power of Track Track. Size. Class of Woods Represented by- » Stone. Gravel. under Each Rail. At A 2 7X9 7X9 7X8 7X8 7X8 7X8 7X8 7X8 Oak, locust, hard maple, hickory, cherry; not tie plated. Longleaf pine, black walnut, beech, birch, elm, gum, hemlock, Douglas fir; tie plated. Inches. 20 20 22 20 20 22 22 20 12 12 12 9 12 6 12 8 18 18 18 14 18 10 18 12 Tons per Square Foot. 1.0 to 1.5 1.0 to 1.5 1.0 to 1.5 l.Oto 1.5 0.8 to 1.2 1.0 to 1.5 0.5 to 1.0 0.5 to 1.0 Pounds per Linear Inch. 700 700 600 B 2 600 Bi 600 c 2 Loblolly pine, shortleaf pine (at times this wood is nearly equal to longleaf), soft maple, catalpa, chestnut, white pine, Norway pine; tie plated. Do . . . 450 450 c 3 Do 450 The low-supporting power of class C track permits the use of weaker woods. A 22-inch tie spacing for this grade of track gives a load at the rail bearing of about 10,000 pounds. The pressure transmitted to the subgrade is determined by the spacing of ■the ties (or more properly by the distance between adjacent ties) and the depth and kind of ballast used. In the table three characters of subgrade are con- sidered, the firmest having a bearing power of from 1.0 to 1.5 tons per square foot and the least firm a bearing power of from 0.5 to 1.0 tons per square foot. By applying the formula [l + sind>) 2 v = 2 yX we see that the firmer grade corresponds to a soil with an angle of repose of from 23 degrees to 31 degrees for 12 inches of stone ballast or 18 inches of gravel ballast under the tie, and from 28 degrees to 36 degrees with 6 inches of stone or 10 inches of gravel ballast under the tie. Table LXXIX shows that these angles of repose fall within the limits given for dry sand, clay, and mixed earth. 318 STEEL RAILS The subgrade, having a supporting power of 0.5 ton per square foot, cor- responds to a soil having angles of repose varying from 13 degrees to 20 degrees under the conditions stated in the table. This agrees with the angle of repose for wet clay shown in Table LXXIX. Table XL VII (article 19) gives, for a subgrade capable of bearing 1.5 tons per -square foot, an allowable load applied to the tie at the rail bearing of from 10,100 to 11,800 pounds, for the size of tie, depth and kind of ballast used in class A track. Owing to the rapid application of the load it has been assumed in article 19 that these values could be safely increased to 14,000 pounds on account of the inertia of the track and roadbed. For 20-inch tie spacing this gives a supporting power of 700 pounds per linear inch of rail. For the track designated by Bi in Table LXXXII, owing to the increase in distance between adjacent ties this value falls to 600 pounds per linear inch of rail. In class B 2 track we find from equations Nos. 1 and 2, article 18, that the allowable load at the rail bearing, as determined by a supporting power of 1.5 tons per square foot on the roadbed, is 9500 pounds in the case of 9 inches of stone under the tie and 8500 pounds for 14 inches of gravel. Making the same allowance for the inertia of the roadbed, as in the previous case, it is seen that a supporting power of about 600 pounds per linear inch of rail is realized. In class B 3 track, if we take the supporting power of the roadbed as 1.2 tons per square foot, we find values from 7700 to 9000 pounds for the load that can be applied to the tie at the rail bearing, which agree fairly well with those previously determined for class B 2 track. The bearing power under each rail, as determined by the permissible load on the roadbed for class C track, has been calculated in a similar manner. It will be noticed that in each case the upper limits of the bearing power of the roadbed have been worked to in determining the values given in the table. This is a feature of the analysis which requires careful consideration of the kind and volume of traffic over the track. The inertia of the roadbed plays an important part in strengthening the track when the maximum loads imposed upon it do not occur too frequently, as in the case of high-speed passenger trains where the most destructive forces to be provided for are those produced by the drivers of the locomotive. In the case of dense freight traffic where the heavy loads imposed by the engine drivers are followed by the passage of a long train, thus subjecting the track to a contin- uing load lasting over a considerable interval of time, the inertia of the road- bed is, in a great measure, overcome and a correspondingly lower value for the allowable pressure on the roadbed must be used. STRENGTH OF THE RAIL 319 The all steel 70-ton coal cars, which are coming into use on some of the large coal-carrying roads in the East, weigh over 50,000 pounds, and have a capacity of 140,000 pounds. This weight is carried on four axles and a train composed of these cars would prove very destructive to the roadbed unless an ample provision was made for the effect of the repeated application of the heavy wheel loads. Examining now the weights of rail required to distribute the wheel loads so as not to exceed the bearing power of the track. Table LXXXIII shows the moments of inertia of standard rails * ; evidently the rails with the highest moment of inertia will give the most favorable loading of the track structure. TABLE LXXXIII. — MOMENTS OF INERTIA AND SECTION MODULI OF STANDARD RAIL SECTIONS. Moment of In- sertion Modulus of A.S.C.E A.S.C.E A.S.C.E A.R. A. type A A.R. A. type A A.R. A. type B A.R. A. type B P.S., Pennsylvania R. R. System. P.S., Pennsylvania R. R. System. P.R.R., Pennsylvania R. R P.R.R., Pennsylvania R. R Dudley, New York Central Lines Dudley, C. R. R. of N. J Dudley, New York Central Lines 29.1 38.0 27.4 49.0 16.11 12.00 9.62 17.78 12.46 15.74 11.08 15.91 12.02 14.29 11.25 17.00 11.76 11.53 In Plate XXVI are given the dynamic wheel loads with different axle "spacing for rails having moments of inertia of 20, 30, 40, and 50. The curves shown on the diagrams are calculated by the method explained in the first part of article 23 and show the allowable dynamic axle loads, as determined by the safe bearing power of the different classes of track given in Table LXXXII. An examination of these diagrams shows that for each class of track the allowable wheel load increases with the axle spacing up to a certain point when a maximum is reached and, as the spacing of the wheels is still further increased, the allowable wheel load decreases. The most favorable axle spacing, as might be expected, is greater for the heavier rails than for those of lighter section. * If the moment of inertia of the section is not known it may be calculated by one of the following methods : Culmann, C. Centralellipse und kerneines schienenprofils, 5 p. 111., 1875. (In his Die graphische statik, ed. 2, p. 475.) Morely, Arthur. Graphical determination of moments, centroids, and moments of inertia of areas, 6 p. 111., 1908. (In his Strength of Materials, p. 117.) Sankey, C. E. P. Note on the graphical determination of moments of inertia, 1000 w. dr., 1910. (In Engineer, London, v. 110, p. 57.) 320 STEEL RAILS Plate XXVII presents diagrams showing the maximum bending moments in the rails under the conditions given in Plate XXVI. In the table shown on Plate XXVII are given bending moments corresponding to an extreme fiber stress of 20,000 pounds per square inch in the base of the rail. In using this table it should be borne in mind that the relation between the moment of inertia and section modulus of different sections vary. The values given in the table represent average conditions. A comparison of Plates XXVI and XXVII shows that the wheel load is determined by the bearing power of the track in the case of classes B and C track, but with class A track the working stress of the steel may be exceeded without overloading the track. The dotted lines in the diagram for class A ' track on Plate XXVI show the correction necessary to apply to the curves of this diagram in order to keep within the working stress of the metal of the rail. Plate XXVI will now serve as a basis for determining the dynamic wheel load corresponding to any section of rail and axle spacing. For a wheel arrange- ment consisting of a series of wheels having the same spacing and each sup- porting approximately the same load, the values of the load may be read directly from the diagrams. This loading satisfies the condition of the calculations which assumes that the tangents to the elastic curve of the rail under the wheels and midway between them are horizontal. When the wheel spacing is not the same for adjacent wheels, the average of the loads given for each axle spacing should be taken. In the case of the front and back drivers the conditions are more complex. Here we may have a trailing truck and either a two-wheel or four-wheel leading truck carrying loads much less than those on the drivers. The preparation of charts for all of these conditions and for the case where the wheel spacing of adjacent drivers is not uniform would appear to be a refinement which would not be warranted by the data upon which the calculations must necessarily be based. It will be observed that little variation in the wheel load occurs after a distance between adjacent wheels of 180 inches is reached, the curve becoming, in most cases, nearly horizontal at this point. In other words the wheels are so far apart as to have little or no effect upon each other. The following formula is proposed to be used in determining the wheel loads on the front and rear drivers, it is also applicable to the outside wheels of the trucks under the cars. W _W W"-W" L W" 2 t- 2 W"^ 2 STRENGTH OF THE RAIL 321 where W = dynamic load of outside driver. W = dynamic load corresponding to the wheel spacing between the outside and adjacent driver. W" = dynamic load corresponding to the distance between the outside driver and the center of truck. W" = the value given below for different moments of inertia and classes of track. L = dynamic load on truck wheels (one side). Moment of In- ertia of Rail. For Front Drivers. Class of Track. For Back Drivers. Class of Track. A. B. C. A. B. C. 50 40 30 20 36,000 30,000 26,000 28,000 26.000 24,000 22,000 18,000 16,000 14,000 12,000 40,000 34,000 30,000 32,000 30,000 28,000 26,000 20,000 18,000 16,000 14,000 w The term — in the formula represents the part of the driving-wheel load which is supported within the driving-wheel base: W" the load carried by the rail outside of the driving-wheel base if there is no leading truck, this is made smaller than indicated by the diagrams of Plate XXVI in the case of the leading driver on account of the probable extra stress set up in the rail when it is first depressed by the weight of the locomotive. The term W" - W" ™ is introduced to provide for the extra support 2 W" afforded by the truck wheels. In the extreme case where W" = L, the wheels ahead of the driver exert the pressure corresponding to their distance from the driver, and the term — ^— drops out of the equation. When L = or there is no leading truck the term W" - W" ; becomes equal to zero. 2 W" The dynamic wheel loads, having been determined, the corresponding static loading can be readily computed by the methods given in article 10 for steam locomotives, article 11 for electric locomotives, and article 12 for cars. Plate XXVIII presents diagrams showing approximately the static loading that can be placed on the rail with different wheel arrangements. From these diagrams can be obtained the weight of rail and design of track necessary to use in connection with engines where the maximum axle load is fixed, or the diagrams 322 STEEL RAILS may be used in determining whether or not it is safe to run a certain weight of equipment over an existing line. On account of the variation in design of engines a separate examination should be made in most cases, as the diagrams, of necessity, represent general conditions which may be varied from in a considerable degree. Fig. A, Plate XXVIII, gives the track diagrams for passenger engines of the Atlantic and Pacific types. The main driver in the wheel arrangement of the Pacific engine can carry more weight than when it is one of the outside wheels, as in the case of the Atlantic engine, and for this reason the former engine is generally the most favorable on the track. The ten-wheel engine is used extensively for passenger and freight service on branch lines. This engine does not have the trailing truck of the two former types, and the rear driver has, therefore, less carrying power than in the Pacific engine, although about the same as the Atlantic where the effect of the trailing truck is offset by the fact that the rear driver is the main wheel. The diagrams given on Fig. B, Plate XXVIII, show the axle loads of ten-wheel engines for classes B and C track. Fig. C shows diagrams for Mogul and Consolidation freight engines. The wheel arrangement of these engines is quite similar to that of the ten-wheel engine, and it will be found that the curves agree very closely with that of the ten-wheel engine used in freight service. On Figs. D and E are diagrams for cars. It should again be observed that these smaller diameter wheels should not be loaded as heavily as the drivers, and the diagrams for the loads on car axles are not extended beyond axle loads of 45,000 pounds. The diagrams of the figures on Plate XXVIII illustrate very clearly the effect of the different wheels on the track, and emphasize the fact that the entire wheel arrangement must be considered in determining the maximum load on any one wheel. The assumption made by most foreign writers on this subject, that the strains produced by the loads are independent of the position of the wheel is obviously incorrect, as has been shown experimentally by Dr. Dudley's strem- matograph tests. The diagrams of Plate XXVIII are not extended beyond 60,000 pound axle loads for drivers or 45,000 pounds for car wheels. With carbon steel rails the use of very heavy loads should be approached cautiously until further evidence is obtained in regard to the effect of such wheel loads on the intensity of the stress at the contact of the wheel and the rail. While axle STRENGTH OF THE RAIL 323 loads of nearly 70,000 pounds are in service on experimental locomotives, they have not been used in sufficient numbers to demonstrate fully their effect on the rail. The lack of proper experimental data presents many difficulties in accu- rately determining the functions performed by the rail. Within certain limits, however, the duty of the rail can be calculated with a considerable degree of accuracy and more attention should undoubtedly be given to the effect of dif- ferent loadings on the rail in the design of the engines and cars which run over it. It must be constantly borne in mind in dealing with the design of the track that in many cases the strength of the rail is not the first consideration in the selection of the section to be used, and that the question of obtaining a rail of the requisite stiffness is of the greatest importance. The sudden failure of any part of the track is not to be anticipated within the limits of customary practice, but rapid deterioration of the structure may take place which will eventually result in failure. Economy of train service has become so important that it is safe to say that there will be no return to lighter loads the tendency is, and will be constantly, in the opposite direction. The importance therefore of giving to the design of the track the same careful investigation as is considered essential in the design of a bridge cannot be over-estimated. The track is, in fact, a continuous girder con- necting termini over which pass the same loads as over the bridges. The discussion of stresses in the ties, ballast and subgrade which has been made in the preceding pages while sufficient to enable the allowable bearing power of the supports of the rail to be determined within reasonable limits, is far from ex- haustive enough in its character to serve as a basis for the general design of the track and the proper proportioning of all the elements entering into its construc- tion. Such an analysis would be clearly outside the limits of the present work and while the various tables and formulae that have been developed appear sufficient for the purpose intended, any general conclusions based upon their evidence alone should be avoided. CHAPTER VI INFLUENCE OF DETAIL OF MANUFACTURE The evidence of the failure of rails of heavy section rolled within the last few years, equaling and at times exceeding that of lighter rails of earlier manufacture exposed to similar conditions of traffic and roadbed, points un- mistakably to defective material in some of the later rails. These rails apparently do not fail in the majority of cases due to too great a stress of the metal, and it is this irregular failure of individual rails due to defects in manufacture which has given rise to such just feelings of dissatisfaction and alarm. Inferior quality of the metal in the rail may be attributed to two causes: first, the use of imperfect methods of manufacture; second, the influence of the form of the section upon the detail of manufacture. First, let us examine the methods employed in the manufacture of the earlier rails, which gave such satisfactory results, and which have been so constantly presented to rail makers as representing that which they ought to do. * The first steel rails were rolled in mills which had been designed for iron rails. Other rolls were used and the number of passes was increased, making the reduction very gradual. All blooms were allowed to cool before being charged into the reheating furnace. After the drawing of one heat and before the charging of another, the furnace was cooled down, then the heat was brought up very gradually and plenty of time was taken to allow the steel to " soak." In the converting house, all the possible practices of crucible steel teeming were introduced. The ingot molds were carefully brushed out, heated and smoked before being used. When the steel was teemed all doors and windows of the casting house were closed and time was not spared on any of the details. It was expected to produce but 50 per cent as much steel as iron rail, and all employees working by the ton were paid twice as much for steel as iron. The constant demand for cheaper prices (Fig. 220) and increased tonnage rapidly changed these conditions. Many of these practices, it is felt to-day, were entirely without reason, and it is difficult to say as a general proposition that the steel produced was better than is * See paper on Steel Rails, and Specifications for Their Manufacture, R. W. Hunt. Trans. American Institute of Mining Engineers, Vol. XVII (1888-89), p. 226. 324 INFLUENCE OF DETAIL OF MANUFACTURE 325 obtainable at the present time. Mr. Bumngton stated positively to the Indiana Railway Commission, at its hearing, that the quality of the metal is to-day much better than it ever was before, owing to the increased knowledge and better machines and mechanical appliances than formerly existed. Mr. James E. Howard, in his report of the accident on the Great Northern Railway, near Sharon, N. D., on December 30, 1911, states: "It is important to consider whether an improvement in the structural condition of rail steel is attain- able. Such seems to be the case, since experimental rollings have furnished rails $I50,_ , , , , , ,$150 1850 1850 1870 1880 1890 1900 I91C YEAP Fig. 220. — Prices of Iron and Bessemer Steel Rails, 1855 to 1910. which, so far as could be ascertained, were free from streaks . . . It is believed to be metallurgically feasible to produce better steel than has at times been offered and accepted." No doubt the failures which have their origin in defective metal are consider- ably augmented by the character of the stress in the rail. On account of the con- centration of the load on a small area, the stress is not distributed, and consequently a metal of a great degree of uniformity is required. With the large wheel loads now in use the injurious effect of inferior material in the rail is much more apparent than in other structures not subjected to such highly localized stresses. The situation calls for a refinement of manufacture not generally realized in practice, and is further complicated by the desire for high carbon to resist the head stresses, with the need for physical properties in the other parts of the rail which could best be obtained by the use of a much milder steel. STEEL RAILS 29. Chemical Composition It was supposed that the chemical character of the steel in the earlier rails accounted for their excellent wear. Among the makers of these rails, Sir John Brown & Co., of Sheffield, England, sent to this country those which, from their excellent service, were considered by railroad engineers as the type of what rails should be. Accepting the chemical theory, rail makers expected that the analyses of these celebrated rails would present steel of exceptional uniformity and purity. The contrary was proved to be the case. Carbon varied from .24 to .70; silicon, .032 to .306; phosphorus, .077 to .156; sulphur, .050 to .181; manganese, .312 to 1.046. The following is the variation found in thirteen rails made by John Brown & Co., England, all of which had given good service: Per cent. Per cent. Carbon 0.24 to 0.70 Manganese 312 to 1.046 Phosphorus 077 to . 156 Sulphur 050 to .155 Silicon 032 to .306 Below is given the analysis of some of the earliest English rails, imported between 1860 and 1870. These rails, low in carbon and all other hardening constituents, have given from thirty to thirty-five years' service before wearing out, not breaking. Rails Used on Southern Railway. Rails Used on P., C, C. & St. L. Railway. Per cent. 0.158 .77 .114 .067 .490 Per cent. 0.273 .28 .05 .04 .025 0.22 .21 .05 .031 .035 Phosphorus Silicon Fig. 221 shows the performance of two rails of very similar chemical com- position, which, however, possessed quite different wearing qualities. * In 1881, Dr. C. B. Dudley, the chemist of the Pennsylvania Railroad, made an investigation to determine the relative relation between the chemical and physical characteristics of steel rails and their power to resist wear. Dr. Dudley found for the average of 32 slow- wearing rails the following composition: Per cent. Carbon 0.334 Phosphorus 0.077 Silicon 0.060 Manganese . 491 * The Wearing Capacity of Steel Rails in Relation to Their Chemical Composition and Physical Properties, C. B. Dudley, Trans. American Institute of Mining Engineers, Vol. IX (1880-81), p. 321. INFLUENCE OF DETAIL OF MANUFACTURE 327 and proposed a formula for the correct composition of steel rails, as follows: Carbon, between .25 and .35; aim at . 30 Phosphorus, not above 0.10 Silicon, not above . 04 Manganese, between .30 and .40; aim at 0.35 Fig. 221. — Comparative Wear of Rails of Similar Chemical Composition. (Trans. A. S. C. E. 1889.) Chemical Composition Year Rolled Time in Service Tonnage over Rail 0.322 per cent Carbon 0.355 per cent. 0.026 per cent Silicon 0.029 per cent. 0.077 per cent Phosphorus 0.108 per cent. 0.492 per cent Manganese 0.490 per cent. 1871 1876 August, 1871 to July, 1879 August, 1876 to July, 1879 7 years, 11 months. 2 years, 11 months. On high side of 5° Curve On high side of 5° Curve Grade 39.6 ft. per mile. Grade 39.6 ft. per mile. 40,061,230 tons. 21,504,824 tons. Table LXXXIV gives the result of his experiments. TABLE LXXXIV. — WEAR OF RAILS (Dudley.) Level tangents Grade tangents Level curves Grade curves Low side level curves. . . High side level curves. . . Low side grade curves. . . High side grade curves. . Tangents Curves Levels Grades Low side curves High side curves All conditions 2 slower wearing 32 faster wearing .0701 .0706 .1277 .0500 .0911 .0801 .1754 .0542 .0992 .0545 .0989 .0650 .1332 .0767 .0506 114.1 113.3 62.7 160.0 123.1 60.1 104.3 158.1 77.8 328 STEEL RAILS Wellington states that the result of this investigation, which showed, or seemed to show, that very hard rails did not wear so well as softer and tougher rails, was taken to indicate that softness in itself was a desirable quality in a rail ; and the painstaking character of the investigation and high reputation of the road having given these conclusions wide dissemination, manufacturers for many years took them as a guide, and produced rails that were too soft. Table LXXXV shows the gradual increase of the hardening constituents in the steel for rails since Dr. Dudley's investigation. TABLE LXXXV. — COMPARISON OF THE CHEMISTRY OF EARLY AND RECENT RAILS Date. Weight of Rail. Lbs. Chemistry. Name. Carbon. Manganese. Silicon. Sulphur. Phosphorus. Des'd: Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. 1881 1885 1892 1896 1899 1908 1909 Per .30 Per Per Per .30 Per .40 Per Per .04 Per Per Per Per 30 42 15 55 35 38 43 45 45 50 47 55 63 45 48 53 55 55 75 80 85 50- 60 60- 70 70- 80 80- 90 90-100 90 ' ::: :56 :: .05* .07 .04 .85 >0 .70 .75 ^80 .80 1.15 1.10 LOO 1.05 1.10 1.10 1.20 1.05 .10 .10 .05 .20 .20 .20 The Carnegie Steel Company Pennsylvania R.R. (Bessemer) .10 * Metal from which steel is It has often been stated that the reason why the earlier rails seem to last so well was due to the elimination of the poorer quality of rails by the service in the track. This statement is not the complete explanation. The older rails were cold rolled by the light wheel loads until the surface was sufficiently hardened to bear the recent heavier loads without much increased abrasion. New rails of the same section and practically the same physical properties would, when subjected to heavier wheel loads, lose more of the metal by wear, before the surface was rolled as hard as the former sections, and their rate would be much faster.* The light earlier sections could carry from 60 million to 75 million tons before they were rough and unsuitable for passenger traffic, and, when in a location where the tonnage was only 250,000 to 500,000 tons per month, would last in the track many years. The six-inch 100-pound Dudley sections of 0.06 phosphorus and 0.65 car- bon laid in 1895 on the New York Central and Hudson River Railroad, when taken up in 1907 had carried 375 million tons with a loss of about one-eighth of an inch in depth on the head of the rail. * Paper by Dr. P. H. Dudley before the Railroad Commission of Indiana, February 20, 1912. INFLUENCE OF DETAIL OF MANUFACTURE 329 0.05 0.1 0.2 0.4 0.6 0.8 1.0 1.3 25.00 26.0 31.0 36.0 43.0 58.0 60.0 44.0 Garbon is the most important element, except iron, in steel. The me- chanical properties of iron-carbon alloys are closely connected with the relative amounts of the two elements. The relation between the percentage of carbon in an alloy and the tenacity in tons per square inch is indicated* in the following table : Per cent of carbon Tenacity, tons per sq. in. The results are shown graphically in Fig. 222. Silicon in small proportions hardens the steel and stands intermediate between carbon and phosphorus in this respect. It is used to prevent unsound or honey-combed ingots, but when so used 60p tends to render the steel unduly hard. Silicon as high as .2 per cent, in high-carbon steel of .5 and .6 per cent carbon, probably has no injurious effect. Phosphorus hardens steel more rapidly 40 - than either carbon or silicon. It increases its rigidity but impairs its power to resist impact. Small proportions render the metal harder without materially affecting its tenacity, but makes the metal at the same 20 time decidedly cold-short. An excess of phos- Fig. 222.- phorus also renders the steel sensitive to high heat. Mr. Robert W. Hunt, in his experiments in trying to make high phosphorus steel in the Clapp-Grimth converter, found that it was necessary to be very careful not to over-heat the steel. | Owing to the exhaustion of the available low-phosphorus ores, Bessemer rail steel is now of necessity a high-phosphorus and low-carbon alloy, the mean carbon being about 0.50 J per cent, while the impurity of phosphorus is limited to 0.10 per cent. Plain basic open-hearth rail steel is usually a low-phosphorus and medium unsaturated carbon alloy, as most of the phosphorus has been reduced by this * H. M. Howe, Engineering and Mining Journal, p. 241, 1887. See also Steel by Harbord and Hall, London, 1911, pp. 347, 348, and a Study of the Elastic Properties of a Series of Iron-Carbon Alloys, Jones and Waggoner. Proceedings American Society for Testing Materials, Vol. XI, 1911, pp. 492^99. t See Proceedings American Society for Testing Materials, Vol. XI, 1911, Dudley, Ductility in Rail Steel. t The chemical composition refers, in this and the following example, to 100-pound rails. rP 0-4 0-8 1-2% Carbon —Tenacity of Iron-Carbon Alloys. 330 STEEL RAILS process from its content in the ores and iron to 0.04 per cent or under. This permits, in this class of steel rails, carbon of 0.63 to 0.75 per cent. Sulphur has little influence on the tensile strength or ductility. The real effects of sulphur, however, are seen during the rolling, a very small per- centage causing a great red-shortness. Its presence in excess of .06 or a maxi- mum of .08 per cent tends to cause cracks to develop during the rolling, which, while they close up and are almost imperceptible in the finished rail, neverthe- less remain as flaws and may form starting points for rupture when the rail is subjected to any sudden stress. With sulphur, it is necessary to work the metal at a high heat to avoid its cracking during manipulation. The " red-short" term means that as the heat approaches the red color the tendency to crack becomes intensified, while the effect of phosphorus on heated metal is to make it hot short or short under high heat; in other words, it will work at a low tempera- ture, but is sensitive to a high one. Apparently the greater part of the sulphur unites with the manganese forming manganese sulphide, which is occluded by the metal as a foreign sub- stance, preventing its welding and breaking up the continuity of its structure. The impurity of sulphur was limited formerly to 0.075 or 0.08 per cent. The manufacturers now charge for this limitation of sulphur five cents extra per hundred pounds, and it is, therefore, being omitted from some specifications, although in most cases it is required that its content be reported. Manganese has a general tendency to increase the tensile strength and reduce the ductility; this influence varying with the amount of carbon pre- sent in the steel and becoming more marked in the case of high-carbon than low-carbon steels. It is possible to keep the manganese down, by the use of a low manganese spiegle, and with low-sulphur steel its presence in excess of .8 per cent, or its use to bring up the tensile strength in place of carbon, is dangerous on account of its very distinct hardening effect when above .6 per cent. In the commercial run of iron, where the sulphur varies, the practice is to allow the manganese to go as high as 1.1 per cent, and some authorities do not consider it dangerous unless above 1.0 per cent even with low sulphur. Manganese tends to neutralize the effect of sulphur and prevent the metal becoming red-short, and, to a limited degree, the cold-shortness produced by phosphorus. The above elements are those generally considered in rail steel, and speci- fications rarely refer to the other elements which may be contained in the ore, and which either from design or accident are present in the finished product. The most important of these are arsenic and copper. The effect of arsenic upon steel was quite fully investigated several years INFLUENCE OF DETAIL OF MANUFACTURE 331 ago by Harbord and Tucket.* The conclusions given by them may be sum- marized as follows: Arsenic, in percentages not exceeding .17, does not appear to affect the bending properties at ordinary temperatures, but above this percentage cold- shortness begins to appear and rapidly increases. In amounts not exceeding .66 per cent the tensile strength is raised very considerably. It lowers the elastic limit and decreases the elongation and reduction of area in a marked degree. Messrs. Ball and Wingham f have investigated the influence of copper on the tensile strength of iron and steel. An alloy containing : Per cent. Copper 7.550 Carbon 2.720 Manganese . 290 Silicon . 036 Phosphorus . 130 Sulphur 0. 190 was bright, white in color, crystalline, and very hard, but did not offer any great resistance to impact. Varying quantities of the alloy were melted down with Bessemer steel, and test pieces 1 inch by | inch by ^ inch were annealed before being tested. The following table shows the results: Number. Copper. Carbon. Tensile Strength. 1 2 3 4 Per cent. 0.847 2.124 3.630 7.171 Per cent. 0.102 0.217 0.380 0.712 Tons per sq. in. 18.3 36.6 47.6 56.0 From these experiments it is clear that copper increases the tensile strength of iron. % The simultaneous presence of carbon tends to prevent the more intimate association of copper with iron. In test piece No. 1, the fractured surface was somewhat fibrous, while No. 2 and the others were highly crystalline. Even in the absence of carbon, copper makes iron extremely hard. Mr. F. Stubbs states that the presence of \ per cent of copper in steel gives to it the property of preventing the oxidation of the steel on being subjected to a burning heat. Copper in steel rails in small quantity does not materially affect the me- chanical properties, but in steels, in which high ductility is required, especially in those with high carbon, copper is objectionable. Steel with copper, say up to 1 per cent, appears to resist corrosion better than the same steel without * On the Effect of Arsenic on Mild Steel, Journal Iron and Steel Inst., Vol. 1, 1 t Iron and Steel Inst., No. 1, 1889. t Steel and Iron for Advanced Students, Hiorns, London, 1903, p. 322. ;, p. 183. 332 STEEL RAILS copper. * Campbell states that 1 per cent may be present without injuring the steel, provided there be but little sulphur; but that if the sulphur be up to .08 or .10, the metal will be red-short, and that copper also reduces the welding power of the metal, especially if sulphur be present; but he adds: " In all cases the cold properties seem to be entirely unaffected." f Richards states that "copper causes red-shortness, but much less than sulphur. Five-tenths per cent may be allowed in rails and its effect is overcome by manganese." X The influence of copper on steel was formerly greatly exaggerated. Whereas it was considered to be very harmful, it is now known, when present in small quantities, to have no serious influence on the physical properties of steel. Mr. H. J. Force reports a case of an 80-pound rail made by the Lackawanna Steel Company in 1895, which had given very good service. An analysis showed about .40 per cent carbon and about .60 per cent copper. § According to a statement in Professor Howe's " Metallurgy of Steel " || an American firm of steel-rail makers habitually made Bessemer tee rails with .51 to .66 per cent copper and they were so slightly red-short that in spite of the thin flanges and low finishing temperature only from 1.25 to 2.5 per cent of them were so defective as to be classed as second quality. Mr. R. W. Hunt states that in the early days of the steel industry excellent rails were produced from Cornwall irons. A large number of these rails con- tained .5 per cent of copper. The Pennsylvania Steel Company, as well as the Bethlehem and the Troy Works, used Cornwall iron containing low phos- phorus and high copper as their basis for a long time. Clamer H has found that the addition of copper and nickel in combination seems to have the same effect upon the steel as if they were individually added, the copper in its effect really being about the same as so much added nickel. It is possible, therefore, to replace part of the nickel in nickel steel by copper, without materially altering its physical properties. Recently Messrs. Burgess and Aston, working quite independently of Clamer, have confirmed these results. The attention of railroad engineers is being directed toward the develop- ment of alloy steel, or steel containing a percentage of various materials intro- duced to give it special mechanical qualities. In general, however, on account of the higher cost of production, these steels are confined to use in special locali- * Metallurgy of Iron and Steel, A. Humboldt Sexton, Manchester, 1902, p. 247. t Notes on Iron, Robert H. Richards, 1895. J Metallurgy of Steel, Harbord, London, 1911, p. 375. § Proceedings American Society for Testing Materials, Vol. X, 1910, p. 279. II Metallurgy of Steel, New York, 1891, p. 83. 1 Proceedings American Society for Testing Materials, Vol. X, 1910, Clamer on Cupro- INFLUENCE OF DETAIL OF MANUFACTURE 333 ties where the conditions are especially severe, as on sharp curves under heavy traffic or in tunnels where it is a troublesome matter to inspect or renew the rails. The requirements of steel alloy may be summarized as follows: (1) High resistance to shock; (2) High elastic limit; (3) Resistance to abrasion. Some of the alloys best known are manganese, nickel, chromium, and titanium. * The record of the chrome nickel on the Central Railroad of New Jersey, and of the plain nickel on the Pennsylvania Lines, Northwest System, is not very good. In a period of six months there were 112 failures per 10,000 tons laid of 85-pound A. S. C. E. section of nickel steel from the Carnegie Steel Com- pany on Pennsylvania Lines, Northwest System, the chemical composition being: Per cent Carbon 44 Phosphorus 09 Manganese 80 Silicon. . . , 10 Sulphur 03 Nickel 3.42 The 90-pound A. S. C. E. section chrome nickel steel from the Bethlehem Steel Company on the Central Railroad of New Jersey for the same period showed failures of 41 per 10,000 tons laid, nearly all of which were broken rails. The same committee reported for the year, ending October 31, 1910, that the record for 90-pound A. S. C. E. open-hearth rail with chromium and nickel on the Central Railroad of New Jersey has been very bad so far as failures are concerned, there having been 1,129 per 10,000 tons of rail laid, mostly break- ages. This rail is 1909 manufacture. Small lots have also been tested on the Baltimore and Ohio and the Erie with a large number of failures. The amount of nickel is 2 per cent to 2 J per cent, and the chromium 0.5 per cent to 0.9 per cent. In most cases these rails showed a very marked resistance to flange wear as compared with ordinary carbon steel rails. It has been found desirable to lower the carbon when the other hardening elements are added. A rail with carbon 0.40, chrome 0.50, and nickel 1.25 is about equal to a 0.60 carbon ordinary rail. Manganese steel with C 0.77, P 0.06, Mn 9.93, Si 0.25, and S 0.038 showed about one-third as much abrasion of the head as ordinary Carnegie Bessemer in a test, on the Norfolk and Western, lasting nineteen months. * Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 11, Part 1, 1910, p. 315. 334 STEEL RAILS Chrome steel, which usually contains about 2 per cent of chromium and .80 to 2 per cent of carbon, owes its value to combining, when in the " hardened" or suddenly cooled state, intense hardness with a high elastic limit, so that it is neither deformed permanently nor cracked by extremely violent shocks. * The tensile strength rises with increase in the percentage of chromium till with about 5 per cent it is about 74 tons unannealed, or 55 tons annealed, the elongation being 13 per cent in the latter and 8 per cent in the former case. The limit of elasticity was 40 tons in the first and 20 tons in the second case. As the quantity of chromium is increased the metal becomes harder, and with about 9 per cent can hardly be touched with the file. In the absence of carbon its hardening influence is not so marked. Forging makes the metal hard and brittle, but the latter property is removed by annealing, and it is rendered excessively hard by quenching. It has a high resistance to shock, and is there- fore suitable for the manufacture of rails. t On low-carbon steels not annealed, the addition of each 1 per cent of nickel up to 5 per cent causes, approximately, an increase of 5000 pounds per square inch in the elastic limit and 4000 pounds in the ultimate tensile strength. The influence of nickel on the elastic limit and ultimate strength increases with the percentage of carbon present, high-carbon nickel steels showing a greater gain than low-carbon nickel steels.J The addition of nickel to steel raises the proportion of elastic limit to ulti- mate strength and adds to the ductility of the steel. This effect of nickel in increasing the ratio of the elastic limit to tensile strength, without sacrifice to ductility, accounts for the increase in the working efficiency of nickel steel over carbon steel; in other words, its increased resistance to molecular fatigue. The exhaustive series of experiments made by Wedding and Rudeloff show that the resistance to compression of nickel-iron alloys increases steadily with the per cent of nickel present, until 16 per cent of nickel is reached. Had- iield has also made a very complete series of experiments on the resistance of nickel steel to compression. He has found that a steel containing .27 per cent nickel shortened, under a compression of 100 tons (224,000 pounds) per * Metallurgy of Iron and Steel, A. H. Sexton, Manchester, 1902, p. 517. t Nickel Steel: Its Properties and Applications. Colby. Proceedings American Society for Testing Materials, Vol. Ill, 1903. t The subject of nickel steel has received considerable attention, notably by D. H. Browne, Trans. American Institute of Mining Engineers, Vol. 29, 1899, p. 569, and A. L. Colby, "A Comparison of Certain Physical Properties of Nickel and Carbon Steel," Bethlehem Steel Company, 1903. See also Guillet, Journal, Iron and Steel Institute, Vol. 2, 1908, p. 177; Waterhouse, Proceedings Am. Soc. for Testing Materials, Vol. VI, 1906, pp. 249-258; Campbell and Allen, ibid, Vol. XI, 1911, pp. 428- INFLUENCE OF DETAIL OF MANUFACTURE 335 square inch, 49.90 per cent in a length of 1 inch; a steel with 3.82 per cent nickel shortened 41.38 per cent; with 5.81 per cent nickel, 37.76 per cent; and with 11.30 per cent nickel, only 1.05 per cent. He states that an ordinary mild carbon steel without nickel, under similar conditions, would be shortened 60 per cent to 65 per cent. He argues that the toughening action of nickel when added to steel is caused in a very intimate combination of the molecular structure, and that this advantage is further enchanced by the fact that the nickel does not show a disposition to segregate in steel like other elements; in other words, it appears to be more intimately combined. Mr. Campbell, of the Pennsylvania Steel Company, made a series of tests to prove what he states to be the current impression among manufacturers of nickel steel, — that the presence of this element prevents segregation. His conclusion is, that there seems to be good ground for the assumption that nickel prevents the separation of the metalloids, but that it does not prevent it alto- gether, and he states that it is not probable that any other agent will ever be found competent for this task. * Howe states that nickel steel, which usually contains from 3 to 3.50 per cent of nickel and about .2.5 per cent of carbon, combines very great tensile strength and hardness, and a very high limit of elasticity, with great ductility. The combination of ductility, which lessens the tendency to break when overstrained or distorted, with a very high limit of elasticity, gives it great value for shafting, the merit of which is measured by its endurance of the repeated stresses to which its rotation exposes it whenever its alignment is not mathe- matically straight. The alignment of marine shafting, changing with every passing wave, is an extreme example. In a direct comparative test the pres- ence of 3.25 per cent of nickel increased nearly sixfold the number of rotations which a steel shaft would endure before breaking. As has been seen, nickel steel has been used tentatively for railroad rails; but while it has the stiffness and resistance to wear which they require, too many rails have broken in use. We may hope that this treacherousness will be pre- vented. It is quite possible that a change in the percentage of nickel may give an entirely different record. The Mayari ore used by the Maryland Steel Company contains a natural percentage of chromium and nickel, and the results with rail made from this ore seem, so far, to be pretty good. Figs. 223 and 224 give the tensile strength and the ductility of many speci- mens of nickel steel from various sources, chiefly, however, from M. Dumas' * Iron, Steel, and Other Alloys, Howe, 1903, pp. 316-324. Contains report of M. Dumas' work. 336 STEEL RAILS important monograph.* The curves here given are taken from his work (pages 18 and 19). A rough resemblance to the manganese steel curves (Figs. 225 and 226) may be noticed. The great increase of ductility in case of manganese steel in the 13 per cent manganese region is reflected in case of nickel steel by a like and very abrupt rise at about 25 per cent of nickel. 260,000 h H h H H f $ . i '** i " <" K- A 1 '^ 140,000 120,000 100,000 80,000 60,000 40,000 20,000 ° $ » ^ffi H 3 *i n $ h h • I i if * iHr a H V $3 o'h \ H h£ h $ \ H ^ H »! '% 1 H ^T m , H i $ $ 4 i 1 2 1 I 1 6 1 8 2 2 2 2 4 26 28 30 32 34 36 38 40 42 44 O = -The Steel has not n PERCENTAGE OF NICKEL ie Steel hi >» cooled by extremely low 3- r- 78°C-»r78°C T efo). fany!, not given. Fig. 223. — Influence of the Proportion of Nickel and Varying Heat-Treatment upon the Tensile Strength of Nickel Steel. (Dumas.) As actually made, manganese steel contains about 12 per cent of manganese and 1.50 per cent of carbon. Although the presence of 1.50 per cent of manga- nese makes steel brittle, and although a further addition at first increases this brittleness, so that steel containing between 4 and 5.5 per cent can be pulverized under the hammer, yet a still further increase gives very great ductility, accom- panied by great hardness, — a combination of properties which, so far as known, v/as not possessed by any other known substance when this remarkable alloy, known as Hadfield's manganese steel, was discovered. Its ductility, to which it owes much of its value, is profoundly affected by the rate of cooling. Sudden cooling makes the metal extremely ductile, and slow cooling makes it brittle; its behavior in this respect is thus the opposite of * " Recherches sur les Aciers au Nickel a Hautes Teneurs," M. L. Dumas, Paris, 1902. INFLUENCE OF DETAIL OF MANUFACTURE 337 60 56 52 48 44 | 40 § 36 z 32 j§28 3 24 S 20 16 12 8 4 ** I 1 1, « } 1 i i j j N i i s 5 ? :•*■ is 8 ® N *tf , S 5 „ * i. j N< I i 1 i .; r* f \ * ( r ® j *f ? V / *~~ ji- -k! j * j I 1 • t /f / \ ? H i T t \ ^ r' I 8 * ♦ i • 10 12 14 16 18 20 22 24 26 28 30 32 34 Legend!- PERCENTAGE OF NICKEL 2="% Elongation in 2 inches. g=% Elongation in 9 or 10 inches. 4=#> a »4 « x _] 4 ,, , not given, -inches. J" = The Steel has received heat-treatment ( annealing! hardening, etc)". = n n ,j> been subjected to extremely low temperature.. Fig. 224. — Influence of the Proportion of Nickel and Varying Heat-Treatment upon the Ductility of Nickel Steel. (Dumas.) 200,000 ^ 190,000 ~ 180,000 §" 170,000 £ 160,000 °"- 150,000 2 140,000 ~ 130,000 ^E 120,000 i 110,000 g 100,000 w 90,000 ^ 80,000 £ 70,000 £ 60,000 50,000 o~j~2~3~4." 5 6 7 8 9 1011121314151617 1819202122 PERCENTAGE OF MANGANESE Fig. 225. — Influence of the Proportion of Manganese < (Howe.) Legend: • = Slowly Cooled Manganese Steel. + = Water-toughened or Suddenly Cooled Manganese Steel. + ^ / , + /* ' ■' / ' i the Tensile Strength of Manganese Steel. 338 STEEL RAILS that of carbon steel. Its great hardness, however, is not materially affected by the rate of cooling. The fact that when cold it is unalterably hard has, however, limited its use, because of the great difficulty of cutting it to shape, which has in general to be done with emery wheels instead of the usual iron-cutting tools. Another defect is its relatively low elastic limit. Fig. 225 shows the remarkable increase of tensile strength which occurs when the manganese rises from 7 to 13 per cent, and the decline of tensile strength as the manganese increases still further. By the contrast be- tween the position of the crosses and the black dots it shows also the remarkable effect of sudden cooling. Fig. 226 shows the corre- sponding changes in ductility. To show that the maxima for tensile strength and ductility coincide, the tensile-strength curve sketched by eye in Fig. 225 is reproduced in Fig. 226. In Fig. 227 is shown the degree to which manganese steel combines tensile strength with ductility, and in Fig. 228 the degree to which it combines ductility with elasticity. These combinations are often taken as a rough measure of the general degree of excellence of • = Slowly Cooled Manganese Steel. a metal for engineering pur- + = Water-toughened or Suddenly Cooled Manganese Steel. ,-, . , , poses. For comparison the corresponding properties of carbon steel are shown by small black dots, which fall in a pretty well-defined band, much below the manganese-steel crosses. These comparisons may, however, give a false idea of the ductility of man- ganese steel. If two metals elongate in a like manner, the extent of their elon- gation may be a fair comparative measure of their ductility; not necessarily so, however, when their mode of elongating is unlike in kind. A bar of carbon steel -t) \ | i | 1 I 2: \ t ..'; 4 \ of / V / + V 7> ! . / \ 1 ^ \ IS + ■ 4 & 1 / # % 1 v? k I /<. $ \ \ / + '/ / 1 0123456789 10 11 12 13 H15 16 17 18192021 22 PERCENTAGE OF MANGANESE Fig. 226. — Influence of the Proportion of Manganese on the Ductility of Manganese Steel. (Howe.) INFLUENCE OF DETAIL OF MANUFACTURE 339 habitually yields by " necking " when pulled in two, contracting greatly just about the place where rupture occurs, while a bar of manganese steel or of brass elongates far more uniformly over its whole length. The use of manganese frogs in severe service on steam roads and for rails on curves of 75 feet radius or less for permanent street railway work has been found preferable to ordinary carbon open-hearth or Bessemer material. Titanium steel, while not strictly an alloy steel, may be conveniently treated under this head. This metal, like vanadium, alu- minum or silicon, produces a sounder ingot, and under the usual practice the titanium goes into the slag and ordinarily there is no intention of producing ti- tanium alloy steel. A progress report of the Baltimore and Ohio shows that the titanium rail with .70 carbon on Kessler's curve is only wearing one-third as fast as the Bessemer steel with .50 carbon, with which it is compared. The results of six months' service on a New York Central crossover carry- ing a heavy tonnage show that the flange wear of titanium rails was very much reduced as com- + !■+ y. + + TENSILE STRENGTH- POUNDS PER SQUARE INCH Fig. 227. — Tensile Strength and Ductility of Carbon Steel and of Manganese Steel. (Howe.) Legend: • = Carbon Steel. + = Water-toughened or Suddenly Cooled Manganese Steel. pared with that of ordinary Bessemer rails.* t The effect of titanium on steel as understood to-day is to give the metal greater density and strength. Recent tests on titanium rail steel made by * Iron Age, March 25, April 29, and August 5, 1909. t The Use of Titanium Rail on the Baltimore & Ohio Railroad. A. W. Thompson. Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 11, Part 1, 1910, and Railroad Age Gazette, November 12, 1909. 340 STEEL RAILS Dr. Waterhouse show the elastic limit to be raised about 6000 pounds above the same steel to which the titanium alloy had not been added. In the 150 rails examined the titanium steel from different parts of the ingot showed a remarkable degree of uniformity.* The first experiments with titanium alloy in rail manufacture were made by the Maryland Steel Company in November, 1907, and this was followed in 1908 by the Duquesne Works of the Carnegie Steel Com- pany, the Cambria Steel Com- pany, and the Lackawanna Steel Company. During the year 1909 the process passed the experi- mental stage and has since been used in a large number of rails and may be regarded as firmly fixed on a commercial basis. During the month of June, 1908, 19 rails were rolled by the Maryland Steel Company, of the usual composition, to which was added 1.5 per cent titanium alloy. This alloy was claimed to increase the elastic limit, ultimate strength, and remove a large percentage of the slag; also to make the rail less brittle and avoid extreme segrega- tion and blowholes, leaving the metal homogeneous, tough, and The use of the alloy resulted in a rail with a composi- tion high in carbon and phosphorus, which even then successfully passed the physical test. The analysis made by the Maryland Steel Company of this rail shows the following: C. Mn. P. . S. Si. N. O. 0.701 0.92 0.086 0.048 0.079 0.004 Nil * See also C. V. Slocum, Mechanical Engineer, Vol. XXIII, 1909, pp. 336-337. _fc± ELASTIC LIMIT- POUNDS PER SQUARE INCH Fig. 228. — Elasticity and Ductility of Carbon Steel and of Manganese Steel. (Howe.) Legend: • = Carbon Steel. + = Water-toughened or Suddenly Cooled Manganese ■ft ne _g ra m e cl Steel. INFLUENCE OF DETAIL OF MANUFACTURE 341 The addition of ferrotitanium to the ladle has an important influence on tho mechanical structure of the steel by acting as a flux or scavenger, and the cleansing effect results in increased solidity and purity of the metal. Ferrotitanium contains 10 to 15 per cent of titanium, 5 to 10 per cent of car- bon, and of other impurities less than 5 per cent; the balance is pure iron which has been electrically refined. In Bessemer steel rail manufacture it is the practice to add from ^ to 1 per cent crushed ferrotitanium in the ladle as the steel is poured from the converter, and then hold the heat in the ladle about three minutes before pouring the ingot. Sulphur and phosphorus do not appear to be reduced ; but in combining with oxygen and nitrogen, forming oxides and nitrides, titanium has an important action in removing these impurities, forming a stable combination of them, which passes into the slag. The New York Central Lines, prior to 1911, obtained rails from the Lacka- wanna Steel Company with ^ of 1.0 per cent of ferrotitanium alloy added to the ladle. The addition to the cost for plain Bessemer was 25 cents per ton for hold- ing the metal in the ladle three minutes after the ferrotitanium was added and $1.05 per ton for the alloy, or a total of $1.30 per ton. In 1911 T V of 1.0 per cent of metallic titanium was added to the metal and the price subsequently reduced, owing to a reduction in the cost of ferrotitanium. It is claimed that this small proportion of ferrotitanium is sufficient to remove the bulk of blowholes and segrega- tion usually found in Bessemer ingots and produce a clean, solid, good-wearing rail. The following table * gives the production of alloy rails in the years 1909 and 1910. It appears that greater effort has been made to improve the Besse- ' mer rail by the use of alloys than the open-hearth rail. 1909 1910 Tons. 35,945 1,028 12,287 1,245 Tons. 195,940 390 4,210 81 Nickel, chrome, and vanadium rails Total 50,505 37,809 12,696 200,621 174,822 25,799 Table LXXXVI gives the specification of chemical composition adopted as recommended practice by the American Railway Engineering Association March, 1912, for carbon steel rails. Table LXXXVII presents the chemical specification adopted January 1, 1909, by the Association of American Steel * Railway Age Gazette, March 16, 1910 (daily edition), and the Iron Age, February 23, 1911, p. 461. 342 STEEL RAILS Manufacturers for standard Bessemer and open-hearth steel rails for A. S. C. E. sections. TABLE LXXXVI CHEMICAL COMPOSITION OF RAILS — American Railway Engineering Association The chemical composition of the steel shall be within the following limits: BESSEMER PROCESS 70 lbs. and over, but under 85 lbs. 85-100 lbs. inclusive Carbon Manganese Per cent 0.40 to 0.50 0.80 to 1.10 0.20 0.10 Per cent 0.45 to 0.55 0.80 to 1.10 0.20 0.10 Phosphorus, not to exceed (When lower phosphor n be secured, a proper proportionate incre OPEN-HEARTH PROCESS n carbon should b 70 lbs. and over, but under 85 lbs. 85-100 lbs. inclusive Carbon Manganese Per cent 0.53 to 0.66 0.60 to 0.90 0.20 0.04 Per cent 0.63 to 0.76 0.60 to 0.90 0.20 0.04 Phosphorus, not to exceed (When higher phosphor , a proper proportionate reduction ir TABLE LXXXVII. arbon should be made.) 81 to 90 Pounds. 91 to 100 Pounds. Per cent. 0.43 to 0.53 0.10 0.20 0.80 to 1.10 Per cent. 0.45 to 0.55 0.10 0.20 0.84 to 1.14 OPEN-HEARTH STEEL RAILS 81 to 90 Pound, 91 to 100 Pounds. Per cent. 0.59 to 0.72 0.04 0.20 . .0.60 to 0.90 Per cent. 0.62 to 0.75 0.04 0.20 0.60 to 0.90 Silicon, not over Table LXXXVIII gives the Pennsylvania specifications revised January 10, 1912, for 85-pound and 100-pound carbon steel rails. TABLE LXXXVIII CHEMICAL COMPOSITION OF RAILS. — Pennsylvania Railroad System. BESSEMER STEEL RAILS Lower Limit. Desired Com- Upper Limit. Carbon 0.45 0.80 0.05 Per cent. 0.50 1.00 0.12 Per cent. 0.55 1.20 0.20 0.10 Silicon INFLUENCE OF DETAIL OF MANUFACTURE OPEN-HEARTH STEEL RAILS Caseation A. Classification B. Lower Limit. Desired Com- Upper Limit. Lower Limit. Desired Com- Upper Limit. Per cent. 0.70 Per cent. 0.75 Per cent. 0.83 0.80 0.20 0.03 Per cent. 0.62 0.70 Per cent. 75 80 0.05 0.12 0.05 0.12 0.20 04 BIBLIOGRAPHY General Luty, B. E. V. — Mathematical relations between increases in cost and increases in durability in steel rails. 1500 w. 1911. (In Railway Age Gazette, Vol. 51, p. 1223.) Dudley, P. H. — Ductility in rail steel. 1800 w. 1911. (In Railway Age Gazette, Vol. 51, p. 289.) Paper before the American Society for Testing Materials. Considers varying composition of rail steel and its influence on the wear. Sandberg, Christer P. — Chemical composition of steel rails and latest developments. 4000 w. 1908. (In Bulletin of the International Railway Congress, Vol. 22, Part 1, p. 13.) The same. (In Engineering, Vol. 83, p. 827.) Discusses effect of different elements on quality and wear of metal. Manganese Steel Rolled manganese steel rail. 1200 w. 111. 1908. (In Railroad Age Gazette, Vol. 45, p. 1536.) Gives results of tests and shows comparative life of rails. Rolled manganese steel rails. 1600 w. 111. 1909. (In Iron Age, Vol. 83, Part 2, p. 1261.) Discusses wear of Manard rail of the Pennsylvania Steel Company. Steward, H. M. — Life of manganese steel rail on curves from service tests made on the elevated division of the Boston Elevated Railway Company. 1500 w. 1908. (In Proceedings of the American Street and Interurban Railway Engineering Association, Vol. 6, p. 333.) The same. (In Electric Railway Journal, Vol. 32, p. 1196.) Titanium Steel Dudley, P. H. — Use of ferro-titanium in Bessemer rails. 3000 w. 111. 1910. (In Journal of Industrial and Engineering Chemistry, Vol. 2, p. 299.) Gives ductility tests of ferro-titanium rails showing them to average several per cent higher than ordinary Bessemer rails in ductility. Believes that range of ductility can be prescribed by proper study of chemical composition. Maltitz, Ed. von. — Der einfluss des titans auf stahl, besonders auf schienenstahl. 6000 w. 111. 1909. (In Stahl und Eisen, Vol. 29, Part 2, p. 1593.) The same, condensed. 1200 w. (In Iron Age, Vol. 84, Part 2, p. 1790.) Gives results of experiments on effect of additions of titanium to Bessemer rail steel. Slocum, Charles V. — Titanium alloy in rails and car wheels. 6000 w. 111. 1909. (In Proceedings of the Railway Club of Pittsburg, Vol. 8, p. 176.) Emphasizes the increased wear and soundness of titanium rails. Slocum, Charles V. — Use of titanium in steel for rails, car wheels, etc. 2000 w. 111. 1909. (In Electrochemical and Metallurgical Industry, Vol. 7, p. 128.) Shows the increased durability and strength of titanium steel and its products. Springer, J. F. — Titanium steel. 2000 w. 111. 1911. (In Cassier's magazine, Vol. 40, p. 483). Considers especially its properties and importance as rail steel. Thompson, A. W. — Use of titanium rail on the Baltimore and Ohio Railroad. 2500 w. 1909. (In Canadian Engineer, Vol. 17, p. 238.) 344 STEEL RAILS Gives properties and tests. Waterhouse, G. B. — Influence of titanium on segregation in Bessemer rail steel. 3000 w. 111. 1910. (In Proceedings of the American Society for Testing Materials, Vol. X, p. 201.) Results indicate that presence of titanium in rail steel lessens segregation and promotes uniformity. 30. Extraction of the Iron from Its Ore Before the process of reduction or " smelting " is attempted at the blast furnace the ore is usually subjected to some preliminary treatment.* The preparatory processes are: (a) " Grading " the ore; (b) Calcination or roasting; (c) Mixing to make up the desired proportions of ore charge. The grading of the ore is not necessary at the furnace when it has already been properly done at the mine. When the sorting at the mines has not been carefully done, or when a greater number of grades than usual are required, sorting is also practiced at the furnace, and the ore is then distributed to the several bins of the stock house, which building is erected as near the furnace stack as possible. f The purpose of roasting is to remove sulphur, carbonic acid, and water and to increase the porosity of the ore. It is accomplished in two ways, — ■ by roasting the ore in a heap, or in a kiln using wood, coal, or gas for fuel. Fig. 229 shows the ore roasters used at the Norway furnace, Bechtelsville, Pa., in 1883.J Lake Superior ores require no roasting, and for this reason very little roasting of the ore is necessary at the present time. The iron ores in the vicinity of Johnstown, which were formerly used by the Cambria Steel Works, contain high sulphur and phosphorus content. The iron content in the ore was but 30 per cent, necessitating roasting before charging into the furnace. These works now use Lake Superior ores having an iron content of from 50 to 65 per cent, and the process of roasting is not necessary. Making up the furnace charge is an operation which demands both a knowl- edge of the chemistry of the blast furnace and of ores. The proportions of the charge are determined by the character of the ore, the fuel, and the flux, by the size and method of working the furnace, and by the character of product required. * Iron and Steel, Materials of Engineering, Thurston, Part 2, 1909, p. 91. t Notes on Iron, Richards. t Roasting Iron-Ores, by John Birkinbine. Trans. American Institute of Mining Engineers, Vol. XII (1883-4), pp. 361-379. INFLUENCE OF DETAIL OF MANUFACTURE 345 The location of the plant is usually chosen according to the cost of assembling these materials and getting the product to the market. Other things being equal, that furnace will be most economically located which is placed near the mines. Where the ores and fuel are widely separated, location is often deter- mined by the facilities for marketing the iron, and the furnace is so placed that the total of all the costs of transportation and of working shall be a minimum. Fig. 229. — Ore Roasters, Norway Furnace, (Am. Inst, of Mining Engineers.) If the quantities transported are 0', 0", 0'" respectively, and the cost of carriage is c dollars per ton, the distance for each being S', S", S'", the total cost (Thurston), K = cO'S' + cO"S" + cO'"S'", should, other things being equal, be made a minimum. The notable present tendency in the iron industry is the lower average iron content in the ores used. * This tendency will undoubtedly continue in the future as the more easily accessible portions of the richer deposits are worked out. As a corollary to this is the observed tendency toward a decentralization of the * Iron Ores of the United States. Report of the National Conservation Commission, Vol. Ill, p. 483, February, 1909. Government Printing Office, Washington. INFLUENCE OF DETAIL OF MANUFACTURE 347 .a h 1.« M 348 STEEL HAILS INFLUENCE OF DETAIL OF MANUFACTURE 349 iron industry, and with a decrease in the iron content of the ore used, involving a corresponding increase in cost of transportation per unit of iron, there will be an increase in the proportion of fuel which goes to the region producing the ore. Sir I. Lowthian Bell in 1884 stated * that while "Wages (in America) are high . . . the geographical position of the ore and coal and of the markets themselves constitute obstacles of a far more insurmountable description. The distances over which ore is conveyed are sometimes very great; as an example, Fig. 233. — Steamer " Augustus B. Wolvin," 560 ft. in length, capacity about 12,000 tons the produce of the Lake Superior mines is carried to Pittsburg, involving car- riage of 790 miles. The cost of transport on the minerals consumed for each ton of pig iron I have calculated f to average 10s., 9d., at the eight chief seats of the iron trade in Great Britain; whereas, in the United States the mean charge at fourteen of the large centers is 25 s., 8 d." The introduction of improved methods for handling the ore in transport and the deepening of the waterways of the Great Lakes J has in a measure overcome the adverse conditions mentioned above. * Manufacture of Iron and Steel, Bell, London, 1884, p. 473. t Report to Her Majesty's Government on Iron Manufacture of the United States compared with that of Great Britain. t William Chandler, History of St. Mary's Falls Ship Canal, 1877. The Great Lakes and Our Commercial Supremacy, John Foord, North Am. Review, Vol. 167, p. 155. Saint Mary's Falls Canal Semicentennial, History of the Canal, John H. Goff, 1907. 350 STEEL RAILS General View of the Dock. Side View of the Dock with Ore Cars on the Structure. Fig. 234. — Great Northern Railway Ore Dock at Allouez Bay, Superior, Wis. (From Science Conspectus.) INFLUENCE OF DETAIL OF MANUFACTURE of the Lake Superior ore Figs. 230 to 234 illustrate some of the features industry. Figs. 230 and 231 show the method of mining the ore by steam shovels employed in northern Minne- sota. The shovels are large, with about 5-ton dippers. The amount of stripping required at these mines is often heavy, amounting in some cases to as much as 100 feet and costing from $0.25 to $0.40 per cubic yard of material removed from on top of the bed of ore. It is generally considered profitable to strip up to a maximum depth which does not exceed the thick- ness of the layer of ore uncovered. Figs. 232, 233, and 234 show the ore docks and the type of vessels used in transporting the ore. * Down to late in the fifties the ore product of Lake Superior was handled over a mule-tram road to Marquette, and as late as 1870 a 700-ton ship was an enormous craft, the loading of which re- quired two days and the unloading be- ing seldom accomplished in that time. In 1871 the largest ore barge carried 1050 tons, now the cargoes reach 14,000 tons. 165,000 tons of ore has been loaded into sixteen steam- ships in one day at the docks of the Duluth, Missabe and Northern Rail- way. The loading of the steamer " H. E. Corey " of 10,000 tons capacity at the Duluth and Iron Range Steel Ore Dock, at Two Harbors, Minn., was accomplished in 39 minutes, f * The Development of Lake Superior Iron Ores. Bacon. Trans. American Institute of Mining Engineers, Vol. XXVII (1897), p. 341. f Scientific American, December 11, 1909. 352 STEEL RAILS The construction of a special type of ship of large tonnage for ore trade, coupled with the invention of unloading machinery of great capacity at the terminal ports, has brought the cost of transportation down to a very low figure. Thus, a ton of ore is now hauled one hun- dred miles by rail from the most distant mines in the Lake Superior range to a Lake Su- perior port, is loaded into cars or into the stock pile at a Lake Erie port at a cost of less than $1.80 per ton. Fig. 235 presents an in- board profile and cross section of the " Wolvin," a representa- • tive of the type of present ore steamers. This vessel is 560 The largest single cargo of ore carried by the " Wolvin " was 11,536 tons, a feat which she performed in 1904. - Ten-ton Bucket of Unloader in Hold of the " vin." (Scientific American.) feet in length, 56 feet beam and 32 feet deep. Fig. 237. — General View of Ore Unloader with Steamer at the Dock. (Railroad Age Gazette.) The " E. H. Gary " in 1905 carried a single cargo of 12,368 tons. In 1906 the "J. P. Morgan" carried a single cargo of 13,272 tons of ore and in 1907 she carried 13,800 tons. INFLUENCE OF DETAIL OF MANUFACTURE 353 354 STEEL RAILS Fig. 236 shows the bucket of the Hulett ore unloader. Four of these machines located at the docks at Conneaut, Ohio, are credited with having taken out of the "Wolvin" 7257 gross tons of ore in four hours and six minutes.* The Hulett unloaders at Gary are showing an average rate of 300 tons per hour Fig. 239. — ■ Blast Furnace with Stoves and Buildings. (Thurston.) for each machine. On July 10, 1912, the "Morgan" discharged 10,091 tons of ore in three hours and ten minutes at Conneaut. This was apparently the fastest time ever made in unloading, but on July 24, 1912, it was surpassed when the "Wm. P. Palmer" was relieved of 11,044 tons in three hours and seventeen minutes, or at the rate of 56 tons per minute. * Saint 1907, p. 201. Gary's Falls Canal Semicentennial, Commerce of the Great Lakes, Ralph D. Williai INFLUENCE OF DETAIL OF MANUFACTURE 356 STEEL RAILS INFLUENCE OF DETAIL OF MANUFACTURE 357 * The coal and ore docks of the Baltimore and Ohio Railroad at Lorain, Ohio, are among the largest on the Great Lakes. The machinery for unload- ing the steamers is the latest design of Brown hoist unloader, driven by elec- tricity and equipped with three grab buckets having a total capacity of 1000 tons of ore an hour. Figs. 237 and 238 illustrate a steamer being unloaded at the dock. The large grab buckets employed scoop up from seven to ten tons of ore each time they are lowered into the hold of the vessel, after which they are hoisted and carried in over the dock on a movable girder, or ram, carried in a heavily braced portal frame, which is itself movable lengthwise of the dock. The buckets may either be dumped into a 75-ton weighing hopper, from which the ore is discharged directly into cars on any one of the four tracks spanned by the unloader, or dropped into the trough space, which has a capacity of 100,000 tons, and is sepa- rated by a concrete wall from the tracks. Once deposited in the trough, the ore may either remain in tempo- rary storage, or be conveyed to the larger storage space covered by the ore bridge. The combination of fast unload- ing plants on the dock front with buckets moving at high speed over a short travel, with a storage bridge of long span, carrying a larger bucket over the storage space, is found on all modern lake docks. The blast furnace is shown by Figs. 239, 240, and 241. It is a brick structure, usually circular in section and built in two parts; the upper part resting on columns, while the lower portion rests directly on the foundation. The upper portion is sheathed with boiler plates. Fig. 242 shows the top rigging of a modern blast furnace. The charge is automatically elevated and dumped into the hopper. In the United States furnaces are worked up to 100 feet high. The best modern practice is, however, about 90 feet high, with a product of 400 to 500 * Railway Age Gazette, July 28, 1911, p. 178. Fig. 242. — Top Rigging of Blast Furnace. INFLUENCE OF DETAIL OF MANUFACTURE 359 tons per day. The following dimensions of the Gary furnaces are typical of the best practice. The blast furnaces (Fig. 243) are 88 feet in height from the tap hole to the top of the furnace lining, and the capacity of each is 450 tons- per day. Each furnace has four blast stoves. The interior diameter of the blast furnace is 15 feet at the hearth, 21J feet at a height 13 to 21 feet above the hearth, and 16 feet at the top. Fig. 244. — The Whitwell Hot-blast Stove. (Thurston.) The earlier blast furnaces were blown with cold air, but later a hot blast was used with an aim to saving fuel, and the air from the blowing engines passed through stoves which were heated by the waste gases from the furnace. Fig. 244 shows the Whitwell stove and Fig. 245 a more modern stove. The first stoves in use were of cast-iron. The gases were burned around and circulated among U-shaped cast-iron pipes enclosed in a fire-brick struc- ture. This process was continuous — a recuperative process. However, it was 360 STEEL RAILS subject to a number of defects, among which was the burning out of the tubes, making it impossible to obtain more than 900° F. in the blast. This type of stove was followed by the fire-brick stove operated on the regenerative princi- ple, and by its use a hot-blast tem- perature of approximately 1500° F. can be obtained. The atmosphere is the most vari- able element involved in the blast- furnace process, which consumes air in large quantities. In furnaces using ore from the Lake Superior district the raw material, amounting to about 7200 pounds per ton of iron, varies in composition within 10 per cent, but the atmosphere, of which 11,700 pounds are consumed per ton of iron, varies in its content of moisture from' 20 to 100 per cent from day to day and often in the same day. Many experiments have been made to determine the most feasible method for extracting the moisture from the air. Various schemes for its direct absorption were worked out and in turn abandoned, and finally Mr. Gayley* designed and put in successful operation the dry-blast process which bears his name. This consists in freezing the moisture out of the air. The Gayley process not only reduces the cost of producing the pig iron, but, which is very much more important, gives a more effective control of the operation and product of the furnace. The product was first put in operation on the Isabella furnaces of the * The Application of Dry-air Blast to the Manufacture of Iron. James Gayley. Trans. American Institute of Mining Engineers, Vol. XXXV (1905), p. 746. The Application of Dry-air Blast to the Manufacture of Iron — Supplementary Data. James Gayley. Ibid, Vol. XXXVI (1906), p. 315. Gayley's Invention of the Dry Blast. R. W. Raymond. Ibid, Vol. XXXIX (1908), p. 695. Fig. 245. — Julian Kennedy Stove. (Harbison- Walker Refractories Co.) INFLUENCE OF DETAIL OF MANUFACTURE 361 J" Carnegie Steel Company, situated at Etna, Pa., a suburb of Pittsburg, on August 11, 1904. The lines and dimensions of this furnace, shown in Fig. 246, repre- sent the usual construction of furnaces in the Pittsburg district. Fig. 247 shows graphically the operation of each day, averaged with all the preceding days from August 1 to September 9, 1904, nclusive; the increase in output and reduction in coke consumption corresponding to the increase in burden; the varying conditions of humidity from day to day, which represent the average humidity for each twelve-hour period ; and the change in humidity after treatment in the dry-blast apparatus. The materials for smelting are iron ores, limestone (flux), and fuel. Charcoal was first used and the iron from this fuel was of excellent quality on account of the low ash and sulphur of the charcoal and its great porosity. It has so little strength, however, that its use in the modern high furnaces is prohibited. Coke is now generally used. Anthracite as a blast- furnace fuel is inclined to decrepitate and give trouble from its fineness. Bituminous coal is not used, as it cakes and absorbs heat for distillation of volatile consti- tuents. * At Gary, Plate XXIX, between the stock pile and the furnace is a line of elevated storage bins arranged in two parallel rows. One row is for coke and the other for ore and limestone. Above the bins are four tracks on which travel two 60-ton electric transfer cars. The ore is loaded into the transfer cars by the buckets of the overhead ore bridges. The coke and limestone are brought up over the bins by rail and deliver their load directly by gravity. At the bottom of the bins are spouts controlled by electrically operated gates, and below these are tracks which run the full length of the bins. Traveling on these tracks are electrically operated lorries into which the ore, coke, and limestone are delivered froii the bin spouts. The lorries carry the materials to what are known as the " furnace skips," of which there is a pair to each furnace. The skips run upon an inclined railway which runs direct from a pit * Scientific American, December 11, 1909. JB£f£_ Fig. 246. — Isabella Fur- nace, Carnegie Steel Company. (Am. Inst, of Mining Engrs') 362 STEEL RAILS 0. j 4- -1 JL JL Ol eo P t 4 14 CO p 4 ^4 4 r- S> 4 4 S I v 4 5 s 4 4 -^ x 4 4^ s s 4 v X I t 8 s 4 7 -tl t S s 4 r ^rt t a s 4 E i'jt i a s t _J ^5 5 -t s S t -y vtt t 8 2 I 1 ^ f 4 2 2 s r r t p r £ 2 i -l 4 H I 2 12 s - j 2 II 4 * 2 4 4 5 V 2 « Ct— fv 1 \k X 2 / v 2 ^ 1 14 IT i o » it 1 4 \ ^ i i> "• =3 < §£ £ 4 14 So * >1 g T 11 1 * It TT &4 5 'S S -5 a S £3 || f !_ '' i u 372 STEEL RAILS INFLUENCE OF DETAIL OF MANUFACTURE 373 Fig. 258. — Bessemer Converter in Full Blast. (Am. Tech. Soc.) 374 STEEL RAILS The molten pig iron contains a large proportion of carbon which is almost burned out during the blow. The combustion of this carbon increases the heat of the metal and the flame, shown in Fig. 258, is at first red, but rapidly be- comes brighter until it can hardly be looked upon by the naked eye. The sudden dropping of the flame after nine or ten minutes gives evidence that the carbon is almost burned out, and the operator turns the converter down and shuts off the blast. Spiegeleisen or ferromanganese is then added to recarbonize the metal. Mr. Wickhorst* gives the following description of the process of making Bessemer steel at the Maryland Steel Company: The metal from the blast furnace was poured into an 85-ton receiver, from which it was weighed and poured into an 18-ton converter. In addition to the hot metal from the blast furnace, cupola metal was used, which ordinarily is the same metal that has been run into pigs and then remelted in a cupola, this being necessary when the Bessemer plant cannot take care of all the metal from the blast furnaces. In the case of this heat, two-thirds of the cupola metal was Lebanon iron. The converter charge was as follows: Pounds. Metal from No. 2 receiver 22,500 Cupola metal 18,000 Scrap steel 1,000 After blowing, 4300 pounds of spiegel was added to the converter and 260 pounds ferromanganese and 30 pounds ferrosilicon added to the ladle during the pour- ing. The analyses of the metal in the converter before starting to blow, and before the addition of scrap and of spiegel, were as follows, special samples being taken for these analyses: Carbon Phosphorus Sulphur Manganese Silicon Copper Nickel or chromium .064 trace 3.96 The basic open-hearth is rapidly supplanting the Bessemer process. This is probably due to the supply of low phosphorus ores being exhausted and the re- duced price of scrap, as on account of the great capacity of the Bessemer process the open-hearth would otherwise have little chance. * Report to Rail Committee, Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 12, Part 2, 1911. INFLUENCE OF DETAIL OF MANUFACTURE 375 The first experiments which eventually led to the development and per- fection of the open-hearth process were carried on by Josiah Heath about 1845. Siemens began his experiments about 1861, while at the same time Martin was independently working on the same problem in France. The first open-hearth furnace introduced into the United States for the production of steel was built by Frederick J. Slade for Cooper, Hewitt and Company, then proprietors of the New Jersey Steel and Iron Company, at Trenton, N. J. This method is sometimes regarded as one of decarburization of cast iron by the addition of uncarborized metal ; it must not be forgotten, however, that the carbon and silicon of the molten pig metal are not entirely taken out or neutralized by the addition of the uncarborized metal, but that the oxidizing flame from the gas which is burned in the furnace plays an important part. One of the principal objects in adding a large amount of scrap is to save time and cost of fuel in the de- carborizing and desiliconizing process as well as to also save the lining of the furnace. * The furnace (Fig. 259) consists of a rectangular bath, hearth, or basin, open at each end for the admission of gas and air at the ports. This hearth is arched by a roof from 9 inches to 12 inches in thickness. At each end of the furnace are two checker chambers, one for the preheating or regeneration of the air, the other of the gas. Before starting the furnace a wood fire is built in one set of chambers (or in the furnace) and after these have attained a dull- red heat the gas and air are passed through them, entering at one end of the furnace, are deflected downward by the direction of the ports, unite in com- bustion over the hearth, and the gases, the products of combustion, leave the furnace through the ports at the opposite end, passing downward through the checkers or regenerative chambers, there giving up their heat to the checkers, thence through the flues to the stacks. At frequent intervals, say from 15 to 20 minutes, dependent on the quality and amount of fuel, charge, working of furnace, etc., the currents of gas and air are reversed, now entering the furnace at the opposite ends and having passed through the checker chambers, heated up during the previous period, take this stored-up heat to create a more intense flame over the bath. These waste gases in turn pass out through the chambers, giving up their heat. This reversal is maintained with regularity until the charge is ready to tap. Fig. 260 illustrates the general arrangement of an open hearth plant. The Talbot continuous open-hearth process employs a tilting furnace which may be operated at a capacity of from 20 tons upward; 100 to 150 or even 200 tons are entirely practicable. The charge is run in from the cupola, * A Study of the Open Hearth, Harbison-Walker Refractories Company, Pittsburg, 1909. 376 STEEL RAILS blast furnace, or mixer, desiliconized wholly and decarbonized largely by a blanket of slag rich in oxides, and reduced ultimately in the usual way. The GAS TRANSVERSE SECTION OF LONGITUDINAL SECTION AT TRANSVERSE SECTION AT REGENERATIVE CHAMBERS CENTER LINE OF FURNACE CENTER LINE OF FURNACE Fig. 259. — Modern Open-hearth Furnace. (Harbison- Walker Refractories Co.) charge is run off and its place supplied by a new charge, the bottom being at no time allowed to become exposed. INFLUENCE OF DETAIL OF MANUFACTURE 377 Figs. 261 and 262 show tilting open-hearth furnaces. Fig. 261 shows a Wellman tilting open-hearth furnace and Fig. 262 was taken at the Jones and Laughlin Steel Company's plant, where the Talbot open-hearth process is employed. More Talbot tilting open-hearth furnaces have been installed, both in this country and in England, than the Wellman furnace. 378 STEEL RAILS The tilting furnaces do away with a great portion of the tap-hole troubles, the taphole being above the metal and slag lines with the furnace in the normal position, and it is consequently only necessary to fill the tap hole with a very light tamping. They also enable the melter to thoroughly drain the furnace bottom of any slag or metal, it being in the stationary furnace often a difficult matter to rabble or splash out all depressions, and any portion of the heat left ""™'«Lani™— . — — -■■ "i '■' , : ■'''"S^"-*. <*£& f S/jf Wm 7 ~-"-~~'. Fig. 261. — Wellman Tilting Open-hearth Furnace. (Am. Tech. Soc.) in such a hole very soon tends to permeate and disintegrate the surrounding bottom The process of open-hearth steel production* at the Gary works is illus- trated by the following description of an open-hearth heat. This consisted of charging limestone and ore into a basic open-hearth furnace heated with pro- ducer gas and piling on scrap. The charging was started at 7.29 a.m. After 2| hours liquid mixer metal was added, and the whole was melted down until * Report of Tests of Open-hearth Rails c M. of. W. Assn., Vol. 12, Part 2, 1911. - Gary Works. Wickhorst. Proceedings Am. Ry. Eng. INFLUENCE OF DETAIL OF MANUFACTURE 379 the tapping test showed carbon .26 per cent by fracture. During the melting small quantities of fluor spar were added at intervals to make the slag more fluid and assist in the melting. The additions of fluor spar started at 2.50 p.m. and amounted to about 1300 pounds total. At 3.00 p.m. a furnace sample was p v .'"■/. >j^ tiit- /^$ ■■ Sir 4: Fig. 262. — Pouring Steel into Ladle of Open-hearth Furnace. (Copyright, Keystone View Co.) taken and the phosphorus found to be .012 per cent. At 4.25 P.M. 150 pounds of ore was added. Mixer metal to recarbonize was added to the furnace at 5.02 p.m. The furnace was tapped at 5.12 p.m. and ferromanganese (80 per cent) and ferro-silicon (50 per cent) were added to the ladle, shortly after tapping. 380 STEEL RAILS The amounts of the various materials used were as follows: Pounds. Limestone 25,000 Ore (Chapin) 15,000 Scrap steel 60,400 Mixer metal, first charge 110,900 Mixer metal to recarbonize 24,000 Ferromanganese 1,000 Ferrosilicon 500 A sample of the mixer metal used to charge the furnace gave the following analysis : Per cent. Carbon 3.85 Silicon 1 . 73 Manganese 1.50 Phosphorus 215 Sulphur 030 (The silicon in the mixer metal ordinarily averaged about 1.25 per cent instead of 1.73, as shown above.) The ferromanganese and ferrosilicon had compositions about as follows: ili Carbon. . . . Phosphorus Sulphur * The hot metal is tapped from the blast furnaces into 40-ton ladles, in which it is hauled to two 300-ton mixers. The metal is poured from the mixers into 60-ton charging ladles, in which it is conveyed to the open-hearth furnaces on electric transfer cars. From these cars the ladles are picked up by a 75-ton traveling crane and the metal is poured into the open-hearth fur- naces through a runner (Fig. 263) . The fact that the Bessemer process has already passed the zenith of its growth is one which has now become well recognized by metallurgists generally. Mr. Talbot has given a very clear presentation of this subject and the author is indebted to him for the abstract of his paper which follows.f The three main causes bringing about the supersession of the Bessemer process are: 1. The ever-growing scarcity of iron ores suitable either for the acid or basic Bessemer process; 2. The superiority of the product obtained * Scientific American, December 11, 1909. f Benjamin Talbot, in the London Times Engineering Supplement, February 13, 1907. INFLUENCE OF DETAIL OF MANUFACTURE 381 by the open-hearth processes of manufacture; 3. The cheapening of the pro- duction of the steel ingot by modern open-hearth methods of manufacture.* The increasing scarcity of iron ores suitable for use in the acid Bessemer process is, perhaps, the most cogent of the three causes named. In the United Fig. 263. — Charging Platform of the Open-hearth Furnaces at Gary. (Scientific American.) States, apart from the Southern States and the northern portion of New York State, there are practically no ores at present available for the manufacture of pig iron suitable for the basic Bessemer process. The rivalry is, therefore, between the acid Bessemer and the basic open-hearth. The former had a long lead, but the growth of the open-hearth rail manufacture has been rapid and in the immediate future the development of the open hearth will be out of all proportion to the further development of the acid Bessemer process. f The total annual capacity for the production of open-hearth rails in the * The cheapening of the cost of scrap, while not mentioned by Mr. Talbot, has been an impor- tant factor. It should also be observed that open-hearth rails are subject to the same mechanical de- fects as Bessemer rails, and it has not yet been proved that their superiority over Bessemer rails is very marked; in fact, some extremely poor open-hearth rails have been made. t Railway Age Gazette, March 16, 1910, daily edition. 382 STEEL RAILS United States is now about 1,500,000 tons, the principal mill being that at Gary, which is turning out 500,000 tons; then Ensley, with 400,000 tons; Bethle- hem, 200,000 tons; Colorado, 200,000 tons; Lackawanna and others of smaller capacity, 200,000 tons. The total capacity of all mills making open-hearth rails up to 1907 was less than 200,000 tons, and in that year production reached 253,629 tons. In 1908 it reached 571,841 tons, and in 1909, 1,256,674 tons. The production * of open-hearth steel rails in 1910 was 1,715,899 tons, against 1,256,674 tons in 1909. The increase in 1910 over 1909 was 459,225 tons or more than 36.5 per cent, while the increase in 1909 over 1908 was 684,833 tons or over 119 per cent. The production of Bessemer steel rails in 1910 amounted to 1,917,900 tons, against 1,767,171 tons in 1909, an increase of 150,729 tons or over 8.5 per cent. Included in the total for 1910 is 68,497 tons of re-rolled rails. In 1911 the produc- tion of open-hearth steel rails was less than in the previous year, but on account of the smaller tonnage of Bessemer steel rails rolled than in 1910 more rails were made from open-hearth steel than Bessemer, f Table LXXXIX gives the production from 1907 to 1911. TABLE LXXXIX. -PRODUCTION OF STEEL RAILS IN THE UNITED STATES FROM 1907 TO 1911. 1907. 1908. 1909. 1910. 1911. Tons. 3,380,025 253,629 3,633,654 Tons. 1,349,153 571,841 1,920,994 Tons. 1,767,171 1,256,674 3,023,845 Tons. 1,917,900 1,715,899 3,633,799 Tons. 1,138,633 1,676,923 2,815,556 Total t In any consideration as to the future of the acid Bessemer process in the United States a thorough understanding of the ore situation is essential. As is well known, the Lake Superior, particularly the Mesaba, ores are the mainstay of pig-iron production in the north. Each year this ore becomes leaner, and there is a difficulty in keeping the phosphorus content of the pig iron manufactured from it below the .1 per cent of phosphorus which is the standard for Bessemer steel in the United States. Steel made from such pig is dangerously near the limit of safety for some purposes, when it is manu- factured by the acid Bessemer process, but when treated in any form of the basic open-hearth process such pig produces a metal of most excellent quality, with phosphorus, when desired, down to .02 per cent, or even less. The carbon content of the steel can also, in the latter class of process, be varied within very * The Iron Age, February 23, 1911, p. 461. t Railway Age Gazette, July 19, 1912, p. 125. t Benjamin Talbot, London Times Engineering Supplement, February 13, 1907, daily edition. INFLUENCE OF DETAIL OF MANUFACTURE 383 wide limits, while it is not so easy to produce .6 to .7 per cent carbon steel in the acid Bessemer process, and even if made, steel with such high carbon and with .1 per cent phosphorus, or thereabouts, is certainly not a material that should be looked upon with favor for rail purposes. All the facts point in one direction. The Bessemer process, while the actual cost of conversion, apart from the question of waste, is perhaps the cheapest, is yet one which requires, either for acid or basic working, a special quality of pig iron, — a quality which is ever tending to become dearer. The waste of metal in the Bessemer must of necessity be higher than in any form of the open-hearth process, and this fact accentuates the importance of the ques- tion of the cost of the pig iron; the higher the price, the greater the cost due to waste. Roughly speaking the loss in a Bessemer is from 8 to 10 per cent and in the open-hearth from 3 to 6 per cent. The margin for economies in the Bessemer process is less than any which can be made in the basic open-hearth process. Unless a radical change is effected in the operation of the Bessemer furnace, only small further savings appear possible. It is true that in some Bessemer the blowing power is still raised by steam obtained from coal burnt under boilers, but even in cases in which the blowing power is obtained from surplus blast-furnace gas, products are absorbed which could otherwise be economically and usefully employed in creating power for other purposes, if the open-hearth process were employed. * The electric furnace is rapidly coming into use as an important factor in steel manufacture, and where water power is abundant and fuel is scarce ' it is extending the boundaries which have for a long time confined the iron and steel districts. Experience with the electric furnace in foreign countries has shown that it will purify the metal to a larger extent than the gas furnace or the Bessemer converter, and it is proposed to use it as an adjunct to the ordinary processes of steel manufacture for the purpose of reducing the amount of phosphorus and sulphur and to deoxidize the bath. After a careful investigation by its metallurgists, the United States Steel Corporation has decided to use a 15-ton Heroult electric furnace at the South Chicago works. Three-phase alternating current will be used, and it is pro- posed to refine the blown metal from the Bessemer converter in the Heroult furnace, reducing the percentage of phosphorus and sulphur, and to use the product for high-grade steel rails. The capacity of one furnace is sufficient for the production of 500 tons of steel in 24 hours. * Railroad Age Gazette, March 12, 1909, and Composition and Heat Treatment of Steel, E F. Lake, 1910, pp. 42-63. 384 STEEL RAILS The Heroult steel-refining furnace is of the crucible type with a tilting rack. The heating is initially effected by means of the electric arc which forms between the surface of the slagging materials which float on the metal bath and the two massive carbon electrodes which are suspended above it. The impurities of the steel are removed by renewing the slag. The refining operation thus be- comes a " washing out " one. INFLUENCE OF DETAIL OF MANUFACTURE 385 The lining is the same as the basic open-hearth and the phosphorus is first reduced and then the sulphur. Recarbonizing is done in the bath by adding crushed electrodes which are 98 per cent pure carbon. Fig. 264 shows a transverse section through the pouring spout of the Heroult furnace at La Praz, and also longitudinal sec- tions of the furnace through the roof. The electrodes, of which there are two passing through the roof, are shown at E on the figure. An alternating current at 110 volts is used. In the Stassano arc furnace the neces- sary heat is obtained by direct radiation from the arc. It is shown in Fig. 265. Various experiments have been made in this furnace to produce steel direct from the ore, but, owing to the difficulty of controlling the composition of the slags with average ores, the production of steel of any required grade is far from easy.* t More than 5000 tons of rails have been made from steel from the electric furnace at the Roechling Iron and Steel Company, Voelklingen, Germany. The furnace is of a special combination electrode and induction type, known as the Roechling Rodenhauser, and takes three-phase current at 25 periods. The pig iron is blown in a basic lined Bes- semer converter, then transferred to the electric furnace for refining at an expenditure of power of 125 kilowatt hours per ton. Re- cently some tests have been published, made Fig. 265. — Stassano Electric Furnace. The furnace is inclined to the vertical and rotated by the mechanism shown below. November 27, 1908. The analysis of the three pieces then tested was as follows: Per cent. Carbon . 75 Silicon 0. 10 Manganese . 67 Sulphur 0.044 Phosphorus . 023 The rails were of flange section, 82.65 pounds to the yard. * Steel, Harbord and Hall, London, 1911, pp. 261-283. f Railroad Age Gazette, July 2, 1909. STEEL RAILS Physical tests were made on these rails; the pieces have a length between punch marks of 7.94 inches and a diameter of almost 1.0 inch, being .975, .966, .984 respectively. These results are given below: Number. Ultimate Stress. Elongation. Reduction of 1 123,341 126,172 122,765 Per cent. 12.25 12.25 13.80 Per cent. 21.00 12.60 20.40 2 3 They show excellent ductility, in conjunction with tenacity. Fig. 266. — • Roechling-Rodenhauser Furnace. (Lake.) The latest development * in connection with the furnace is its operation by a three-phase current, with a frequency of 50 periods for a 15-ton furnace. Fig. 266 shows this furnace in sectional elevation and plan. It is claimed that a special feature of the furnace is the rotation of the charge due to the presence of a rotatory field, as in an induction motor, which insures an automatic circu- lation in the bath. The furnace is essentially a transformer with a primary winding A round both iron cores H of the transformer. The secondaries are two in number; one is the molten bath in the form of an 8, the channel D * Steel by Harbord and Hall, London, 1911, pp. 261-283, and The Report of the Canadian Com- mission appointed to investigate the Different Electro-Thermic Processes for the Smelting of Iron Ores and the Manufacture of Steel in Operation in Europe. INFLUENCE OF DETAIL OF MANUFACTURE 387 between the two cores being very broad. The other secondary is the copper winding B, which is connected with the metal plate E. The electric furnaces, just described, show the three distinct types which are claiming the serious attention of metallurgists. In the present state of Fig. 266. — Roechling-Rodenhauser Furnace. (Lake). (Continued). development of the electric furnace it cannot compete as regards cost of pro- duction with a modern large open-hearth furnace for the manufacture of rails, and it is only when a superior quality is required that it can be employed. The steel from different parts of the ingot shows a very regular compo- sition and is remarkably free from segregation of impurities. The mechanical properties are extremely good. 388 STEEL RAILS Some recent experiments in the United States show that steel made in the electric furnace has a greater density, and within the range of .08 to .75 carbon, shows 10 per cent greater strength than open-hearth steel of the same chemical composition. * The duplex process is a combination of the Bessemer and the open- hearth, and is particularly applicable to pig iron containing too high silicon for advantageous working in either basic Bessemer or basic open-hearth. In the acid Bessemer converter the preliminary blast removes the silicon, together with a considerable portion of the manganese and a certain amount of the carbon. The desiliconized metal is then transferred to the basic open- hearth, where the phosphorus and the remainder of the carbon is eliminated in accordance with the usual practice. f The Jones and Laughlin Steel Company has been experimenting for some time with the duplex process in its present Pittsburg plant, with the idea of using a portion of its Bessemer capacity for preparing metal for its open-hearth furnaces, thus decreasing its output of Bessemer steel and correspondingly increasing the open-hearth output. The Maryland Steel Company has com- pleted five open-hearth furnaces and is using a considerable portion of its Bessemer capacity to duplex with the new open-hearth furnaces. These moves in the direction of duplexing represent a distinct desire to find a new use for Bessemer capacity because there is not sufficient employment for it in its old function. The casting ladle, or the ladle which receives the finished steel for casting into molds, is shown in Fig. 267. If slag is allowed to pass into the ingot molds with the steel the latter is liable to be spoiled, and in consequence the steel can- not be poured from a lip into the molds, but has to be tapped or teemed from a hole in the bottom of the ladle. The time allowed after the conversion of the steel and when it is held in the converter or casting ladle exercises considerable influence upon the finished product. The thorough mixing of the recarbonizer, and the oppor- tunity for the impurities to separate from the metal and the gas to escape from the molten steel are of importance. Dr. P. H. Dudley requires a definite in- terval of time between the additions of the spiegel and the teeming of the steel. He says:{ " Restricting the ingots to three-rail lengths and holding the steel three minutes after recarbonizing, in connection with the dry blast at South * A Study of the Open-hearth, by Harbison- Walker Refractories Company. t Railway Age Gazette, March 18, 1910, daily edition. t Proceedings American Society for Testing Materials, Vol. VIII, 1908, p. 112. INFLUENCE OF DETAIL OF MANUFACTURE 389 Chicago, shows a marked reduction in seams and cracks in the bases of rails. In a lot of 2500 tons of these rails hardly a trace of seam has been found." The dry blast referred to is the Gayley process of furnishing air, practically free from aqueous vapor, to the converters while blowing the charge. This & Fig. 267. — Details of Casting Ladle. (Harbord and Hall.) A, Goose-neck; B, stopper rod; L, sliding bar carrying goose-neck; M, M 1 , M 2 , bolts for attaching lever, P; P, lever bar; Q 1 , Q 2 , brackets on ladle to guide sliding bar, L; K, screw bolt for holding sliding bar rigidly in position previous to teeming; F, fire-clay sleeves threaded on steel stopper rod, B; Z, teeming nozzle; E, fire-clay stopper head; G, nozzle box; H, trunnion; C 1 , C 2 , C 3 , C 4 , cotter pins; S, forged head on sliding bar through which end of goose-neck is passed, and is fixed by cotter pin, C 4 . decreases the amount of iron oxide in the bath which von Maltitz claims to be a principal agent in producing blowholes. That time should be given for the necessary chemical reaction after the addition of the recarbonizer and before casting the metal into ingots, has been known for at least thirty years. It was known that such time was also impor- tant for the escape of the occluded gases, and the value of this latter knowledge was manifested by the several devices for accelerating their escape which, years ago, were either proposed or actually used. These ranged from the thrusting into the ladle full of molten steel a wooden pole, or placing in the ladle before it received the steel from the converter pieces of wood saturated with kerosene, to more elaborate devices, for agitating the steel while in the casting ladle by 390 STEEL RAILS power-driven, refractorily protected screws. It was the practice at some of the Bessemer works to again put on the blast after the introduction of the recarbonizer, and then to partially turn the vessel up, thus agitating the charge. Mr. Robert Forsyth sought to accomplish the desired results through his transferring ladle arrangement, by which the ladle after receiving the steel from the converter was transferred by a hydraulic ram from the receiving crane to the ladle or casting crane. This he did when remodeling the Union Steel Plant, Chicago, about 1886. Later he put the same arrangement in the South Works of the Illinois Steel Company. Later Mr. William R. Walker carried this further by pouring the steel over the top of the receiving ladle into the casting ladle through a nozzle in the bottom of which it was cast in the usual way. Prof. Henry Fay * has observed the moon-shaped fractures in the base and the thermal cracks in the head of the rail which he believes to be generally found along a streak of manganese sulphide, extending in the direction of the rolling. The cause of the manganese sulphide being in the steel he infers is probably the lack of time given for the steel to purify itself after the addition of the recarbonizer. When the spiegel or ferromanganese is added to the bath, the manganese combines with the sulphur, and, given time enough, man- ganese sulphide, having a specific gravity less than that of steel, will rise to the surface. Manganese sulphide melts at 1162° C. Its specific gravity is 3.96, or about half that of steel. It is a glassy, hard, and extremely brittle material. The steel from which the rail is made solidifies at about 1450° C, and the manganese sulphide will not solidify until it reaches 1162° C. Therefore, the manganese sulphide is in a fluid state some time after the steel solidifies. If the rolling of the rail starts, we will say, at a temperature above 1162° C., this material will be rolled out in thin strips in the direction of rolling. It is plastic below the melting point and it is capable of being rolled out while in the plastic condition into long, thin strips. He states: f " That manganese sulphide when existing in certain forms is a harmful constituent of steels can no longer be doubted. The remedy seems to be a very simple one. Specifications should be so drawn as to limit the amount of sulphur in the steel. At the present time most of the specifications do not even mention sulphur. Having done this, the next step is to allow the metal to stand a longer time after the addition of the ferromanganese. With the * Journal Association of Engineering Societies, July, 1908, p. 28. t A Microscopic Investigation of Broken Steel Rails; Manganese Sulphide as a Source of Danger. Fay. Vol. VIII (1908), Proceedings American Society for Testing Materials. Further Investigations of Broken Steel Rails, Fay and Wint, ibid., Vol. IX. INFLUENCE OF DETAIL OF MANUFACTURE 391 specific gravity of manganese sulphide 3.966 and steel 6.82, it should rise to the surface and be skimmed off with the slag if given sufficient time. Usually this time interval between charging of the ferromanganese and the pouring of the ingot is very short. The desire of the manufacturer to increase his output has led him to cut down this interval to the shortest possible limit, with the natural consequence of a large number of defective rails. A longer time interval will allow the metal to purify itself." Mr. E. von Maltitz* found that where recarbonizing is done in the ladle and insufficient time allowed for the complete reduction of the iron oxide in the bath, an excessive number of gas holes may be formed. The presence of gas seams tends to cause unsound metal. Mr. Robert Job has pointed out that in nearly every case of failure due to crushed heads the section shows marked unsoundness, and the vertical flaws of the gas seams weaken the head greatly. The fact should be emphasized that it is not alone sulphide of manganese which is a source of danger, but other forms of slag are also to be looked upon with suspicion. f These may be summed up as follows: 1. Excessive slag (manganese sulphide, silicate, etc.). 2. Segregation of slag concentric with the section. 3. Remnants of slag in the large split portion of the head. 4. Slag in those areas where flow of metal has occurred, or where micro- scopic cracks have developed. The rails illustrated in Figs. 268 and 269 show the effect of unsound metal in the head of the rail. Referring to Fig. 268, view 1 shows a section of the rail which has been polished and etched with acid. It shows some segregation and flow of metal, as expected from the rolling. The rail was slivered, breaking off the right of the head as indicated. This view shows also the portions into which this section was cut and the marks by which they are identified; these were in part polished and examined microscopically for defects as shown in the other views of this figure. View 2 shows the grain size at the center of the head and view 3 shows the finer grain near the surface and the distortion of the grains by wheel action. The photograph is taken at the end of a crack, and shows, besides this, some * Blowholes in Steel Ingots. E. von Maltitz. Trans. American Institute of Mining Engi- neers, Vol. XXXVIII (1907), p. 412-447. t Iron and Steel Magazine, August, 1905 (Job) ; and Journal of the Iron and Steel Institute, p. 301, 1905 (Captain Howorth). 392 STEEL RAILS small cavities, which were more noticeable before etching, and which might have been minute oxide pits or pockets. View 4 shows the metal, which is the white ground mass, to be badly con- taminated by slag, which is extended longitudinally by the process of rolling. These slag lines were found to some extent over the whole surface of this piece, but were worst in the neighborhood of the point indicated by the dot By, view 1. This is shown on the picture, which was taken at the edge of the localized portion. leSSIM' Cross Section at point C 2 , 1 68,000 grains per sq. in. - Crushed Head. Fig. 269 illustrates another example of a crushed head due to unsound metal. View 1 shows a section of the head taken at the point of greatest dis- tortion. The cavity in the top of this view is a drilled hole. On one side of the head a cavity which did not show on the surface, but indicated marked breaking down of the metal, was revealed. The metal, however, is more uni- form throughout this rail than was the case in the rail of the preceding figure. View 2 shows the grain at the center of the head; view 3, like view 3 of Fig. 268, is taken at the end of the crack. It shows the finer grain and distor- tion of the same, and shows as well the further distortion of the metal at the INFLUENCE OF DETAIL OF MANUFACTURE 393 end of the crack as a sort of tearing action. The end of the crack is at the corner of the picture; the further direction of progress of the failure is shown by the black defects extending across the photograph. A longitudinal section of this rail made on portion G showed slag lines, as in the rail of Fig. 268, somewhat most abundant at the point q, though the num- ber was not so great as in the rail of the preceding figure. 1 1 J »'« ♦ ill . ih! << i •1 i' IV • I i«i v r .' ■r Ir" View 3. Cross Section of point Hu,, Mag. 100. View 4. Longitudinal Section on Top of Portion B, Mag. 50, Unetched. Fig. 268. — Crushed Head. (Continued.) * The deleterious influence of slag inclosures in steel has perhaps escaped attention to some extent owing to the fact that in ordinary tensile tests, taken in a direction parallel to that of rolling, these inclosures only occupy a very small proportion of cross-sectional area and possess a tapered shape which allows of gradual distribution of the stresses imposed on the material. If, however, we consider the case of transverse stresses, or of shock or vibration, it will be seen that these inclosures will be fractured as soon as the metal undergoes any material deformation, and then each such inclosure practically represents an internal * " Slag Inclosures " in Steel, by Walter Rosenhain. International Association for Testing Materials, 5th Congress, Copenhagen, 1909. McGraw-Hill Book Company, New York. 394 STEEL RAILS INFLUENCE OF DETAIL OF MANUFACTURE 395 fissure which is ready to extend — and actually does extend — in any direction compatible with the applied stresses. Fig. 270. — Teeming Ingots at Bessemer Converter. (Copyright, Keystone View Co.) 32. The Ingot The principal points in connection with this part of the process are as follows: 1. Care must be exercised in casting the ingot. 2. The ingot must be in a perpendicular position until the interior has had time to solidify. 3. The steel must not be overheated in the heating furnace or soaking pits. 4. Defective material from the top of the ingot must be excluded from the finished product. STEEL RAILS From the casting ladles the steel is run into cast-iron ingot molds located on cars, as illustrated in Figs. 270 and 271. Table XC presents data showing the time required to pour the steel at different mills. After solidifying, the Fig. 271. — Teeming Ingots at Open-hearth Furnace. (Copyright, Keystone View Co.) ingot mold cars are run under the stripper, shown in Fig. 272, from which hooks are lowered and engage the lugs on either side of the mold and lift it off the ingot. The ingot is then taken up by a traveling crane and conveyed to the re- heating furnaces or soaking pits, shown by Figs. 273 and 274, to allow the tem- perature in all parts of the ingot to become equalized before rolling. Fig. 273. — Soaking Pits — Gary. (Scientific American.) 398 STEEL RAILS O .3 INFLUENCE OF DETAIL OF MANUFACTURE 399 TABLE XC. — TEEMING PRACTICE AT AMERICAN RAIL MILLS (Compiled by Committee on Rail, Am. Ry. Eng. Assn., 1909, and revised by the author 1912) fAlgoma Steel Co *Bethlehem Steel Co *Cambria Steel Co Carnegie Steel Co ♦Illinois Steel Co jlndiana Steel Co ♦Lackawanna Steel Co ♦Maryland Steel Co Tenn. Coal, Iron & R.R. Co.. Canadian Soo, Can. \ Bethlehem, Pa Johnstown, Pa Braddock, Pa South Chicago, 111. . Gary, Ind Buffalo, N.Y Sparrows Point, Md. Birmingham, Ala — J mm. Omin. 8 min. 2.15 2.07 2.1 to 1.18 Note. — Information froi t Compiled by author. t. W. Hunt & Co., except that marked (*), which was obtained direct from manufacturers by the The unsoundness of the ingot results from several causes: 1. A funnel-shaped cavity or pipe at the top of the ingot. 2. Dispersed cavities or blowholes throughout the ingot. 3. Segregation of the impurities of the steel, as silicon, phosphorus, man- ganese, etc., from the mass of the metal and their concentration in different parts of the ingot. The pipe is due to the contraction of the interior of the mass after the out- side has set. After molten steel has been cast into an iron mold, the metal in contact with the bottom and the sides begins first to solidify. After a relatively short while the top of the ingot, which is exposed to the cooling action of the air, also becomes solid and the ingot now consists of a rigid metallic shell holding a mass of molten steel, as shown in Fig. 275. As the cooling proceeds this solid shell increases in thickness; but since steel, like most substances, undergoes a considerable contraction in passing from the liquid to the solid state, the mass of metal which when liquid was sufficient to fill the space within the solid shell will, after it has in turn solidified, be unable to fill it and a cavity must necessarily be formed in the upper part of the ingot. The piping of ingots has been known for a number of years.* Robert Forsyth at the Union Steel Works in 1888 demonstrated the relation of the length of the pipe to the position of the ingot while its interior metal was solidi- * The Manufacture of Bessemer Steels by R. W. Hunt, Lecture delivered at The Franklin In- stitute, January 21, 1889. See Journal of the Franklin Inst., May, 1889. STEEL RAILS fying, by breaking a number of ingots which had been differently handled — some placed in a horizontal position as soon as possible after being cast, and ,. . Fig. 276. — Section of Ingot, 17 ins. Square at Top, 19 ins. Square at Base, and 50.5 ins. long, Containing Cavity of 128 cubic inches. (Am. Inst, of Mining Fig. 277. — Bloom from an Ingot of same Heat and of same Size as Fig. 276, show- ing Reduction of Cavity. (Am. Inst, of Mining Engrs.) others so placed at varying intervals up to having been kept vertically until all of the steel was thoroughly set. The best modern practice is to charge the hot ingots into the reheating furnaces to equalize their heat for blooming as soon as possible after they are teemed, stripped, and weighed. An interesting experiment was tried by Dr. P. H. Dudley to determine INFLUENCE OF DETAIL OF MANUFACTURE 401 the relation between the pipe in an ingot which had been allowed to get cold and one which had been promptly charged into the reheating furnace.* Fig. 276 is a photograph of a three-rail ingot, for 100-pound rails, teemed in a mold 19 inches square on the base, 17 inches square on the top, and 66 inches long. The ingot, poured 50.5 inches long, was well deoxidized, and therefore had a large cavity. The ingot had a volume of 7.4 cubic feet, inclosing a shrink- age cavity of about 128 cubic inches, practically 1 per cent of its volume. This is a larger percentage than would be found in rail steel not so well deoxidized, or which contained numerous blowholes. Fig. 277 is a photograph of the bloom of an ingot of the same heat and length, cut for a 9 per cent mill discard. The ingot, after stripping and a subse- quent ride of 500 feet, was charged directly into the reheating furnace without allowing the temperature to fall below the recalescence point, while the bulk of the steel was several hundred degrees above, and in about 2 hours the ingot was drawn and bloomed. The cavity was small and less than one-tenth of that of the cold ingot of the same heat. Blowholes generally form in the upper half of the ingot, which is permeated by honeycombs or dispersed cavities, due to the liberation of imprisoned gases, principally hydrogen, as well as nitrogen and carbon monoxide. These gases are absorbed, dissolved, or occluded in the molten steel, but are wholly or partially evolved and collect into bubbles when the metal begins to solidify. These bubbles are generally more numerous towards the side of the ingot. The evolution of the gases in the mold seems probably to be due to two causes: First, by the reduction of the temperature, the solvent power of the steel for the gases is lowered and, consequently, certain proportions of the gas are liberated; and, second, an evolution of carbon monoxide (CO) or carbon dioxide (C0 2 ), due to chemical action. t According to Howe, blowholes may be lessened or even wholly prevented by adding to the molten metal shortly before it solidifies either silicon or aluminium, or both. An addition of manganese has a like effect. J These ad- ditions seem to act in part by deoxidizing the minute quantity of iron oxide and carbonic oxide present, in part by increasing the solvent power of the metal for gas, so that even after freezing it can retain in solution the gas which it had dissolved when molten. But, since preventing blowholes increases the volume of the pipe, it is often better to allow them to form, but to control their posi- * Discussion of Henry M. Howe's paper on Piping and Segregation in Steel Ingots, Trans. Ameri- can Institute of Mining Engineers, Vol. XL (1909), pp. 821-830. t Iron, Steel, and Other Alloys, Howe, 1903, pp. 369-372. Contains record of Brinell's experiments. t Titanium deoxidizes the steel in a very marked manner, as shown in Fig. 285. STEEL RAILS tion, so that they shall be deep-seated. In case of steel which is to be forged or rolled, this is done chiefly by casting the steel at a relatively low tempera- ture, and by limiting the quantity of manganese and silicon which it contains. Brinell finds that, for the conditions which are normal at his works at Fagertsa, Sweden, if the sum of the percentage of manganese plus 5.2 times that of the silicon is as great as 2.05, the steel will be so completely free from blowholes as to have an undesirably large pipe. If this sum is 1.66, there will be just that small quantity of minute, hardly visible blowholes which, while sufficient to prevent any serious pipe, is yet harmless. If this sum is less than 1.66, blowholes will occur and will be injuriously near the surface unless this sum is reduced to .28. He thus finds that this sum should be either about 1.66, so that the quantity of blowholes shall be harmlessly small, or as low as .28, so that they shall be harmlessly deep-seated. These numbers must be varied with the variations in other conditions. In general, either a higher casting temperature, or a smaller cross section of the ingots, or the use of hot or that of thin-walled molds, calls for a smaller quantity of silicon and manganese. Brinell also finds that an addition of .0184 per cent of aluminum is ap- proximately equivalent to the presence of manganese and silicon in the pro- portions Mn + 5.21 Si = 1.66 per cent; i.e., it unaided gives rise to structure B (Table XCI). Naturally, little or none of this aluminum remains in the steel. It oxidizes to alumina, which rises to the surface of the molten metal, or is found lining the walls of the pipe. Table XCI and Figs. 278 to 284 give some of Mr. Brinell's results. TABLE XCI. — INFLUENCE OF MANGANESE AND SILICON UPON BLOWHOLES AND PIPES (Brinell, loc. eit., p. 370.) Mn + 5.2 X Si. 2.05 1.66 1.16 Cast too hot Cast too colcN No blowholes, but a small pipe. No visible blowholes, no pipe. External blowholes, no pipe. Fewer blowholes and somewhat deeper seated. The blowholes are very deep-seated. Many external blowholes and a pipe, Many blowholes, both external and internal. Injured by the pipe. Just compact enough; excellent. Injured by the external blowholes. Blowholes still harmfully near the surface. Excellent. Injured by the external blowholes. ^Injured by the external blowholes. The structures and H are those induced by too high and too low a casting temperature respectively. The steel which here has structure would, if cast at a normal temperature, have had structure A. It was thought that the reason INFLUENCE OF DETAIL OF MANUFACTURE 403 Fig. 278. — Structure A. — Brinell's Tests. Fig. 279. — Structure B. — Brinell's (^L- 1 * J?2 ^\\ % '\J\® Fig. 280. — Structure C. — Brinell's Tests. Fig. 281. — Structure D. — Brinell's Tests. Fig. 282. — Structure E. — Brinell's Tests. Fig. 283. — Structure 0. — Brinell's Tests. Fig. 284. — Structure H. — Brinell's Tests. 404 STEEL RAILS why the excessively high temperature caused these external blowholes was that it caused the carbon of the molten steel to react on the iron oxide on the surface of the mold, with the formation of carbonic oxide gas, which itself forms these blowholes. Von Maltitz* gives the following as the means for the prevention of blow- holes in steel ingots: 1. Medium temperature of the heat during the last period of the process in the converter or open -hearth. 2. Careful avoidance of overblowing or overoreing of the heat; careful boiling out of the last portion of ore added to the bath. 3. A finishing slag not too rich in oxygen and having the proper degree of fluidity. 4. The destruction, by stirring the heat before tapping, of the ferrous oxide formed. 5. Addition of sufficient deoxidizing material to the heat, and the allowance of sufficient time for the complete separation of the manganese protoxide, silicate of manganese or alumina thus formed, into the slag. f Howe maintains that the gas contained in the blowholes is partially absorbed and the blowhole walls to some extent weldable during the process of rolling. This action probably is less favorable in direct rolling of rails (i.e., rolling direct from ingot to rail at a single heat) than in reheating practice, in which the bloom into which the ingot is rolled is held in a special bloom-heating furnace before rolling into a rail. Segregation is one of the important questions before the steel maker. It is, therefore, natural that for many years it should have engaged the attention of iron and steel metallurgists in different countries, and have given rise to an important literature. Steel contains different impurities, as silicides, phosphides, carbides, sul- phides, etc., whose freezing or solidifying points vary, and all have a lower melting point than the metallic iron, consequently those having the lowest melting point will tend to gradually segregate from the iron and concentrate in the hottest part of the ingot. The top and center of the ingot always con- tains the larger proportions of impurities. All steels do not necessarily exhibit excessive concentration of impurities. * Blowholes in Steel Ingots, E. von Maltitz, Trans. American Institute of Mining Engineers, Vol. XXXVIII (1907), p. 445. t The Welding of Blowholes in Steel, Henry M. Howe, Proceedings American Society for Test- ing Materials, Vol. X, 1910, p. 168. INFLUENCE OF DETAIL OF MANUFACTURE 405 The highly segregated portions of an ingot are often very small isolated areas in the interior of the mass. It is highly probable that a large part of the segregates in steel ingots is directly traceable to the formation of blowholes. The pressure of the cooling gas on the mixture of pure solids and impure liquid in which it forms must squeeze out some of the impure liquid, which passes outward, ascends to the top of the ingot, or finds its way into previously formed blowholes. Below are presented the results recently obtained by Waterhouse* on segregation in acid Bessemer rail steel. They point in the same direction as those published in 1905 by Talbot, which showed the important influence of aluminium in greatly retarding segregation in certain cases. In the present instance, titanium, when rightly applied in the proper amount, was also found to retard segregation of sulphur, phosphorus, and carbon, in what is normally quiet, quick-setting steel. The ingots used were from an ordinary rail-steel heat, and from a heat to which had been added 64 pounds of ferrotitanium, which amounted to only .25 per cent of the weight of the heat. The ordinary steel was made in the usual way. After the heat was turned down, the proper amount of molten spiegel was poured into the vessel. The heat was held there a short time, poured into the ladle, and then through a lj-inch nozzle into the ingot molds. There were six molds. After three ingots had been poured a ladle test was taken. The third ingot of the six was allowed to cool while still standing on its stool, and was then cut through longitudinally. The heat in which ferrotitanium was used was made in exactly the same way. As the steel was poured into the ladle, the alloy was shoveled in; the heat was then held in the ladle for three minutes before pouring the ingots. In this case also the third ingot of the heat was cooled in an upright position and cut through longitudinally. An analysis of the ferrotitanium gave: Per cent. Carbon 10.50 Titanium 11.60 Iron 74. 12 Silicon 1 .60 Manganese 0.30 Calcium trace Photographs of the ordinary and titanium ingots are shown in Fig. 285. The noticeable feature is the increased soundness of the titanium steel, due to the concentration of the blowholes in the pipe cavity. * The Influence of Titanium on Segregation in Bessemer Rail Steel, G. B. Waterhouse, Proceed- ings American Society for Testing Materials, Vol. X, 1910, p. 201. 406 STEEL RAILS The analyses of the ladle tests from the two heats were as follows: Carbon. Sulphur. Phosphorus. Silicon. Manganese. Ordinary steel Titanium steel Per cent. 0.44 0.47 Per cent. 0.098 0.068 Per cent. 0.088 0.093 Per cent. 0.117 0.118 Per cent. 0.91 0.95 W^ 3 v : N! m « teel. Titanium Steel. Fig. 285. — Ordinary Steel Ingot and Titanium Steel Ingot. (Am. Soc. for Testing Materials.) No trace of titanium could be found in the latter steel, so that it is not, strictly speaking, a titanium steel, but will be called so for the purpose of dis- tinction. In the accompanying diagrams, Figs. 286 to 291 inclusive, are shown the results obtained from determinations for sulphur, phosphorus, and carbon. A if-inch drill was used, and drillings were taken to a depth of f inch. The INFLUENCE OF DETAIL OF MANUFACTURE 407 diagrams are drawn to scale, so that the location of the drillings can be readily seen. The methods used were the same for all the samples and all the deter- minations were made by one man. The results are briefly considered in order. Sulphur segregates the most. In the ordinary steel it has risen from .098 per cent in the ladle test to a maximum of .223, and there is a considerable '?£"■ • if % 3 % s . ■'¥ '? . '%* V s ■% J if y i s •'? ■«" ■"i 'if J i° 'i 3 % s -/7^ : -w %-S ■076 .09/ ,C*5 JOSS .07/ .OSS .07S .OSS h)|^ .067 .OG3 O*/ i, *• — uc 1,^. Fig. 286. — Normal Ingot, Half Section. Fig. 287. — Titanium Ingot, Half Section. Sulphur in Ordinary Steel. Sulphur in Titanium Steel. (Am. Soc. for Testing Materials — Waterhouse.) area with more than .147, which is 50 per cent more than the ladle test. In the case of the titanium ingot, the contrast is very remarkable. The greatest result is .101, which is not quite 50 per cent more than the ladle test, .068, and the segregated area is very much smaller than in the case of the ordinary ingot. It is true that there are two factors which may partly account for this difference in results: the titanium ingot is somewhat smaller, and there is less sulphur in the steel as a whole. The fact remains, however, that there is much less segregation of sulphur in the titanium than in the ordinary steel. 408 STEEL RAILS In the ordinary steel the phosphorus has risen from .088 per cent in the ladle test to a maximum of .167, and here also the segregated area is seen to be considerable. In the titanium steel the maximum is .124, starting with a ladle test of .093, and the segregated area is more restricted than in the case of the ordinary steel. The ordinary steel is in a better condition to start with . 1 ./o, .,/+ o** • "• * °Z 7 ' C9 i 5? i „ .OJ6 • • • • • • • L /8i ". * rf' Fig. 288. — Normal Ingot, Half Section. Fig. 289. — Titanium Ingot, Half Section. Phosphorus in Ordinary Steel. Phosphorus in Titanium Steel. (Am. Soc. for Testing Materials — Waterhouse.) than the titanium steel, as it has slightly less in amount (.088 as compared with .093), so that the behavior of the phosphorus is a good test of the pre- ventive power of the titanium. The results given in the diagrams Figs. 288 and 289 show it to have been effective. The titanium steel shows less segregation of carbon than the ordinary steel, and it must be remembered that it starts with .47 as compared with .44 per cent. The highest results found are .67 in the one case and .69 in the other, INFLUENCE OF DETAIL OF MANUFACTURE 409 and the diagrams show that the ordinary steel again has the larger segregated area. The results of the silicon and manganese determinations are not given; they are somewhat erratic in each case, but do not exhibit segregation. Mr. Henry M. Howe presented a very complete discussion on Piping and /rj-" St ,66 .SO r r •*' v ,ss .so .sz .SO STa .SO .SS .S2 .S6 .S2 .67 .S6 .S3 .SS .S6 .60 S6 .S9 .S7 .60 .S0 .S7 .S/ .4-9 .S7 >, * * ' * ' T J =» Fig. 290. — Normal Ingot, Half Section. Fig. 291. — Titanium Ingot, Half Section. Carbon in Ordinary Steel. Carbon in Titanium Steel. (Am. Soc. for Testing Materials — Waterhouse.) Segregation in Steel Ingots, at the London meeting (July, 1906) of the American Institute of Mining Engineers,* of which the following is an abstract. The first part of this paper treats of the causes and the restraining of piping in steel ingots, the second considers the causes and the restraining of segregation, and the third proposes certain precautions in engineering specifications concerning these two defects. An article coming from such a source is necessarily of value * Piping and Segregation in Steel Ingots. Howe, Trans. American Institute cf Mining En- gineers, Vol. XXXVIII (1907), p. 3-108. 410 STEEL RAILS in any consideration of these subjects, and it will be pertinent to briefly review it. Professor Howe infers that the pipe is chiefly due to what may be called the virtual expansion of the outer walls of the ingot in the early part of the freezing, and finds that the upper and smooth-faced part of the pipe probably forms while the interior is still molten, but that the lower, steep, and crystal- faced part probably forms in metal which is already firm. Of the causes which may cooperate to limit the depth of the pipe, it is suggested that three, namely, blow holes, sagging, and the progress of freezing from below upwards are usually effective. The pipe may be lessened by casting (1) in wide ingots; (2) in sand molds; (3) at the top instead of at the bottom;* (4) slowly; (5) and with the large end up; (6) by the use of a sinking-head or other means of retarding the cooling of the top; (7) by permitting blowholes to form; (8) and by liquid compression. It is believed that although the reasons why (1) casting in wide ingots and (2) in sand or clay-lined molds shortens the pipe do not apply to show that they should raise the segregate, yet the position of the segregate should be raised by the six other means by which the pipe is shortened (see 3, 4, 5, 6, 7, and 8 in preceding paragraph). The means proposed for lessening the degree of segregation, as distinguished from raising the position of the segregate, are next considered. These are: 9. Quieting the steel by adding aluminium. 10. Casting in small instead of in large ingots, and hastening the solidifica- tion, not only by casting in small ingots but also 11. By casting at a low temperature. 12. By casting in thick-walled iron molds (i.e., those of high thermal con- ductivity) ; and 13. By casting slowly. It is pointed out that quieting the steel has materially lessened segregation in certain cases, and that segregation is probably much less in small than in large ingots. The effectiveness of the different methods of fluid compression (see Figs. 294-297) is considered, and it is concluded that the beneficial lifting effect on the segregate should be the greatest in Williams' system, which compresses the * Ingots are now practically all cast from the top, absolutely so in regard to rail steel. About twenty years ago there was a great deal of bottom casting practiced, in casting the ingots at the Penn- sylvania Steel Company's Works, which were rolled into rails at the Cambria Company's Works, Mr. A. L. Holley first used bottom casting. INFLUENCE OF DETAIL OF MANUFACTURE 411 ingot chiefly in the middle of its length; it should be the least in Whitworth's system, which compresses the ingot more at its top than elsewhere; and it should be intermediate in the systems of Illingworth and Harmet, which compress the ingot equally in all parts of its length. Finally, stress is laid on inspection at the rolls and shears, and especially on axial drilling of the billets or other products. Figs. 292 and 293 * present experimental verification of the following pre- dictions made in this paper: A. That the pipe is shortened and the segregate raised: 1. By slow casting. 2. By casting with the large end up instead of down. 3. By retarding the cooling of the top, e.g., by means of a sinking head. B. That the pipe is shortened by slow cooling. C. That the pipe and segregate lie in the last freezing part. The procedure was to cast ingots of wax containing a little bright-green copper oleate (usually 1.5 per cent) under varying conditions; to saw each ingot open along a longitudinal plane passing through its axis; and to examine the longitudinal section thus laid bare. The segregated or enriched parts are shown by the darker areas in the photographs, indicating the green of the segregated copper oleate. Taking up the evidence in detail, the influence of the rate of casting is shown in ingots Nos. 1, 2, and 3, Figs. 1, 2, and 3. The casting of No. 1 was finished in 30 seconds and that of No. 2 was so slow that, though it was continuous except for momentary interruptions for heating the wax, it lasted 1 hour and 13 minutes. The pipe in the fast-poured No. 1 stretches down 90 per cent of the ingot's length, and, except for some very thin bridges, is practically continuous for 49 per cent; whereas in the slowly cast ingot the pipe stretches down only 14 per cent of the length of the ingot. In this particular ingot (No. 2) there is a second rudimentary pipe near the bottom, caused by the accidental pouring at first faster than was intended. In ingot No. 3, which was poured slowly from the start, this second pipe is absent. The segregate in the fast-poured ingot No. 1 can be traced at A near the bottom of the ingot. The slow-cast ingot No. 2 has a succession of local axial * The Influence of the Conditions of Casting on Piping and Segregation, as shown by Means of Wax Ingots. Howe and Stoughton, Trans. American Institute of Mining Engineers, Vol. XXXVIII (1907), p. 109. 412 STEEL RAILS horizontal segregates, and in the still more slowly cast ingot No. 3 these local segregates are so small as almost to escape notice The effect of casting with the large end up instead of down is shown in Figs. 4 and 5, which represent two ingots cast in immediate succession and under otherwise like conditions. The pipe stretches down only 30 per cent of the in- got's length when the large end is up, but 82 per cent when the large end is down. The segregate lies well above the center in the ingot with the large end up, but very near the bottom in that with the large end down. INFLUENCE OF DETAIL OF MANUFACTURE 413 The effect of retarding and of hastening the cooling of the top of the ingot is shown in Figs. 6 and 7 and in Figs. 8 and 9. The depth to which the pipe reaches as a nearly continuous cavity is only 26 per cent of the ingot's length in the hot topped ingot No. 6, but 85 per cent in the cold-topped No. 7. The pair of ingots Nos. 8 and 9 which were slow cooling do not show so well the influence of the distribution of temperature on the position of the pipe. The effect of the rate of cooling is shown in Figs. 8, 9, and 10. Figs. 11 and STEEL RAILS 13 illustrate what Professor Howe calls "surface tension bridges." In the middle and lower part of No. 11 there are five bridges from F to J and at K and L, as well as at M of Fig. 13, there are the remains of bridges. These are in each case greener than between the bridges and appear to have been formed on account of Fig. 294. — Illingworth's Press for Compressing Steel Ingots Horizontally while Solidifying, Sectional Plans. In I, the mold is shown ready for receiving the molten steel. Two distance-bars, DD, are set between the halves of the split mold B and C. After the steel has been poured into the mold, these distance-bars are pulled out lengthwise, and the two halves of the mold are then forced towards each other by means of the ram F , shown in II. The convex edges of the distance-bars are for the purpose of making an initial depression in the side of the ingot lest part of its side should be forced out as a fin or welt into the crevice between the two halves of the mold. (Trans. Am. Inst, of Mining Engrs., Vol. XXXVIII.) the local enrichment of the oleate, making the wax so fusible and plastic that it stretches instead of cracking open when the pipe is being formed. The same phe- nomena was noticed at E, F, G, of Fig. 12. The ingot of this figure had its cooling Fig. 295. — Williams' Abdominal Liquid Compression of Solidifying Steel Ingots. The ingot is cast in its mold as shown at I. After its outer crust has solidified the mold is opened, as shown at II, and a liner B is slipped between mold and ingot. A strong cap A is then fastened down, and by means of pressure applied through the ram C the abdominal protuberance on the ingot is forced in, so as to close the pipe and lift the segregate into it, as shown at III. (Trans. Am. Inst, of Mining Engrs., Vol. XXXVIII.) hastened on the right-hand side and retarded on the left-hand side, which resulted in shifting the pipe distinctly to the left of the axis. Several methods have been used to produce sound ingots, as stirring the steel in the casting ladle to allow the gases to escape; casting on a turntable that is made to revolve and the metal run into a mold at its center; bottom casting, with a closed top instead of the ordinary open-topped molds; and casting under pressure. INFLUENCE OF DETAIL OF MANUFACTURE 415 There are different methods of exerting the pressure on the fluid metal in the mold. At the Krupp mills, fluid compression was tried by applying the pressure exerted by carbonic anhydride , . in its fluid state, the ingot mold being capped after the ingot was cast and con- nected to a reservoir containing the car- bonic anhydride. At the Edgar Thompson works the same principle was applied, using steam under a pressure of about 200 pounds per square inch. Under this steam pressure the ingot of 5 or 6 inches diameter shortened in length from 1| to 2 inches. Illingworth's process (Fig. 294) consists of casting in vertical molds, split lengthwise. The two halves are separated during the casting, but when the crust is formed they are brought together by a ram. Williams' system (Fig. 295) employs the split mold, and the two sides are pressed to- gether with a liner between. The Whitworth process (Fig. 296) con- sists of using a steel mold which is placed in a hydraulic press and the fluid steel sub- jected to a pressure of about 6 or 7 tons per square inch of horizontal section. Un- der this pressure the ingot shortens about 1| inches per foot of its length. This pro- cess produces an ingot of uniform quality throughout and in a great measure over- Fig. 296. — Whitworth's Hydraulic Press for the Compression of Steel Ingots while Solidifying. A, main compression-cylinder. B, its plunger. C, the carriage on which the mold or flask sits. G, boss against which the steel in the mold is forced. KK, steel jackets for the mold. LL, the mold proper. MM, perforated cast-iron lag- ging. NN, inner sand lining. comes the difficulty experienced from the ( Trans - Am - Inst - of Minin s En & s -> VoL * *■■ * w u i 'J • • XXXVIII.) formation of blowholes and piping. The Harmet process (Fig. 297) consists in using a tapering mold and com- pressing the fluid by means of a hydraulic ram acting on the open end of the mold. The effect of the tapering mold is to exert a lateral pressure which tends to close up any axial pipes. The French Government require 28 per cent crop in uncompressed ingots and only 5 per cent in compressed ingots made at the St. Etienne works by the Harmet process. 416 STEEL RAILS The test pieces cut from the compressed ingots show, without forging or rolling, as good results under tensile and impact tests as test pieces cut from ingots of the same composition which had been forged with a reduction of two times in the cross-sectional area. There is a very marked diminution of segre- gation, the chemical analyses at the top and bottom of the ingot being sub- stantially the same. The compressed ingot has a grain of a visibly finer structure and the large cleavages often found in sections cut from uncompressed ingots are not found. The metal is sound and thoroughly homogeneous. Fluid compression of the steel in the ingot, when in proper hands, according to our present evidence, prevents pipes, blowholes, and cracks almost com- pletely, and, to a limited extent, segregation. While its introduction would certainly lead to complication at the mills, the benefits to be derived warrant a trial of this method. As has been seen the greatest defects are found Fig. 297.-Harmet : s Liquid com- in the upper part of the ingot, and to obtain a pression by Wire Drawing. sound ingot it was generally specified that a certain The ingot, a A .is cast in a strong discard or crop snou i d be made from the top of conical mold, 27, reinforced with hoops, 28. strong pres- the ingot, which it was supposed would contain all, sure at the base of the ingot, 26, or near i y a u f the imperfect metal. forces it lengthwise of the mold, thus compressing it radially. To get definite knowledge on this point Dr. P. (Trans. Am. Inst, of Mining H. Dudley experimented by lettering the rails formed from different parts of the ingot. The rails were let- tered "A" for the top rail, " B" for the second rail, and " C " for the third, or rail from the bottom part of the ingot. These letters could be found in the tracks, and, as was to be expected, the "A" rails have a larger percentage of impurities than the " B " or " C " rails. They wear faster, developing more surface defects, and at several points upon the road (the New York Central), under heavy traffic, after 10 or 12 years' service, have become practically worn out for main-line traffic, while the "B" or "C" rails are still good. The Committee on Standard Rails of the American Railway Association reported at the meeting of the Association, April 22, 1908, on this subject, as follows: All rails are to be branded with the name of the maker, the weight of the rail, and the month and year; and the number of the heat, and a letter indicating the portion of the ingot from which the rail was made, shall be plainly stamped on the web of each rail, where it will not be covered INFLUENCE OF DETAIL OF MANUFACTURE 417 by the splice bars. Rails to be lettered consecutively " A," " B," " C," etc., the rail from the top of the ingot being " A." In case of a top discard of 20 or more per cent, letter " A " will be omitted. All rails marked " A " shall be .kept separate and be shipped in separate cars. While railway engineers formerly specified a definite percentage of discard from the ingot, they now unanimously agree that the specifications should not state definitely how much should be sheared from the bloom, but that sufficient material should be discarded from the top of the ingots to insure sound rails. Records of rail failures which have been kept for a number of years disclose the incontrovertible fact that, where a 15 per cent discard might do for one ingot, 50 per cent would not be adequate for another.* In its report the Committee of the American Railway Association says: With regard to the discard question, the Committee has always held that it would be preferable to test the finished product rather than specify as to the details of mill manufacture, and the Committee arranged for a trial lot of rails to be rolled from the ingot without any discard whatever, except such as was necessary to enable the bloom to enter the rolls, and after these rails had been cut into small pieces they were broken under the hammer and the fracture ex- amined. This test proved to the satisfaction of the Committee that if "pipes" or other physical defects were present they could be detected by this means. The test also proved quite conclusively that it is possible so to conduct the process of manufacture that the "pipes" or other physical defects will be re- duced to a minimum, and that these defects may not occur at all, even in rails rolled from the top portion of the ingot. In order to avoid an unnecessary waste of good material, the Committee set about to devise means by which the rejection of defective material could be insured without requiring an arbitrary and definite percentage of discard in every case, and a committee of the Pennsylvania Railroad, pursuing the same line of investigation, adopted a tentative specification which provided for a physical test of this nature, and which further provided that when physical defects were discovered all top rails of the heat should be rejected. A trial lot of rails, of a section corresponding to " type B" (Plate VIII),was rolled un- der this specification as to discard, and the results convinced the committee that a development of this idea would prove the best solution of the discard problem. Some of the advocates of a fixed and arbitrary discard have argued that the mere provision of a discard to insure the elimination of " piped " rails, or rails containing physical defects, was not sufficient, and urged the rejection of * See Paper by W. C. Cushing before the Indiana Railroad Conmission, February 20, 1912. 418 STEEL RAILS a fixed percentage from the top of the ingot, because of the well-known fact that segregation occurs in the upper portion. This question of segregation was given careful consideration by the Committee, and while it is a fact that, due to the rearrangement of the constituent parts of the metal during the process of cooling and solidification in the ingot mold, any analysis of the metal in the finished rail will often show a wide departure from the analysis required by the speci- fications, it is also true that an analysis of the metal taken from the different parts of the finished rail will frequently show similar wide variation. This discrepancy is due to the fact that the test ingot referred to in the specifications, and upon which the chemistry specification is based, is taken from the ladle before the metal is poured into the ingot mold, and, consequently, before the segrega- tion takes place. It has been assumed that, because of this variation from the standard composition of the metal in the finished rail, the rejection of all segregated metal would be warranted. But, on this assumption, it would be necessary to discard more than a third of the upper part of the ingot to be on the safe side, as the segregation frequently extends that far; and, while our knowledge of the subject is not so complete as we could wish it to be, we have a great deal of evidence that rails of good physical condition can be made from the upper portion of the ingot. Furthermore, the analyses of a large number of rails, taken after years of service, indicate that these wide variations in chemical composition may occur without apparently affecting the safety or wearing quality of the rail; and, since it is impossible to check the analyses of the finished rail with that of the test ingot, the question arises as to what limits should be placed on the variation which will be permissible. None of the experts con- sulted are ready to say what this limit should be, and all admit that no facts are available as the results of actual experience which would warrant the adoption of any fixed limit to govern the rejection of material. The provision in the new specifications for stamping the rails to show their position in the ingot will enable us to obtain more definite information on this point in the future. BIBLIOGRAPHY Beikirch, F. O. — Verfahren zur verhiitung der lunkerbildung in schweren rohstahlblocken, 1800 w. 111. 1905. (In Stahl und Eisen, Vol. 25, Part 2, p. 865.) Describes use of sinking-head, afterwards cut off. Piped portion is thus removed. Daelen, R. M. — Die verfahren zur verhiitung der lunkerbildung in stahlblocken. 1800 w. 111. 1905. (In Stahl und Eisen, Vol. 25, Part. 2, p. 923.) The same. (In Zeitschrift des Vereines Deutscher Ingenieure, Vol. 49, Part 2, p. 1398.) Describes fluid compression methods, methods of heating moulds and continuous process, proposed by writer. Dormus, A. V. — Die blasen- und lungerbildung des flusseisens. 1000 w. 111. 1902. (In Zeit- schrift des Osterreichischen Ingenieure- und Architekten- Vereines, Vol. 54, Part 1, p. 279.) INFLUENCE OF DETAIL OF MANUFACTURE 419 The same, translated. (In Sibley Journal of Engineering, Vol. 17, p. 128.) Describes formation of blow-holes and pipes in steel and gives mechanical and chemical means for prevention. Dudley, P. H. — Dark carbon streaks in segregated metal in split heads of rails. 2000 w. 111. 1909. (In Proceedings of the American Society for Testing Materials, Vol. 9, p. 98.) The same. (In Railway and Engineering Review, \ ol. 49, p. 626.) Heroult, P. L. T. — Presence and influences of gases in steel. 800 w. 1910. (In Transactions of the American Electrochemical Society, Vo . 17, p. 135.) Concludes that blow holes are the result of disengagement of carbon monoxide in steel. Howe, Henry M. — Does the removal of sulphur and phosphorus lessen the segregation of carbon? 2500 w. 1907. (In Proceedings of the American Society for Testing Materials, Vol. 7, p. 75.) Results from examination of many cases indicate that removal of sulphur and phosphorus does not lessen segregation of carbon. Howe, Henry M. — • Further study of segregation in ingots. 5000 w. 111. 1907. (In Engineer- ing and Mining Journal, Vol. 84, p. 1011.) Suggests that quiet, resulting from increased ingot-size and slow cooling, may explain why these conditions do not always favor segregation. Howe, Henry M. — Influence of ingot-size on the degree of segregation in steel ingots. 800 w. 111. 1909. (In Transactions of the American Institute of Mining Engineers, Vol. 40, p. 644.) Howe, Henry M. — Influence of top-lag on the depth of the pipe in steel ingots. L000 w. 1909. (In Transactions of the American Institute of Mining Engineers, Vol. 40, p. 804.) Howe, Henry M. — Piping and segregation in steel ingots. 106 p. 111. 1906. (In Transactions of the American Institute of Mining Engineers. Vol. 38, p. 3.) Discussion, Vol. 39, p. 818. 33 p. Considers causes and prevention of piping and of segregation and precautions to be taken regarding these in specifications. Howe, Henry M. — Segregation in steel ingots. 1000 w. 1908. (In School of Mines Quarterly, Vol. 29, p. 238.) Summarizes results of author's investigations. Howe, Henry M., and Stotjghton, Bradley. — Influence of the conditions of casting on piping and segregation, as shown by means of wax ingots. 3000 w. III. 1907. (In Transactions of the American Institute of Mining Engineers, Vol. 38, p. 109.) Verifies by experiments views expressed by Howe in earlier paper. Huston, Charles L. — Experiments on the segregation of steel ingots in its relation to plate specifications. 3000 w. 111. 1906. (In Proceedings of American Society for Testing Materials, Vol. 6, p. 182.) Illustrates and explains cases of segregation. Job, Robert. — Investigation of defective open-hearth steel rails. 1500 w. 111. 1909. (In Pro- ceedings of the American Society for Testing Materials, Vol. 9, p. 90.) Discussion, p. 106 The same. (In Railway Age Gazette, Vol. 48, p. 523.) Shows failures to be due to unsoundness of metal. Knight, S. S. — Observations on segregation phenomena as applied to cast steels. 3000 w. 111. 1910. (In Iron Trade Review, Vol. 46, p. 475.) Paper before Philadelphia Foundrymen's Association. Illustrates examples of segregation and emphasizes need of further investigations. Lilienberg, N — Piping in steel ingots. 2000 w 111. 1906. (In Transactions of the American Institute of Mining Engineers, Vol. 37, p. 238.) Considers methods for prevention of piping, with special attention to Illingworth's side-compression method. Mathesius, W. — Herstellung von poren- und lunkerfreiem grauguss, stahlguss und schmiede- stucken durch anwendung von thermit 2500 w. 111. 1903. (In Stahl und Eisen, Vol. 23, Part 2, p. 925.) Riemer, Julius. — Ein neues verfahren zum verdichten von stahlblocken in flussigem zustande. 2000 w. 111. 1903. (In Stahl und Eisen, Vol. 23, Part 2, p. 1196.) The same, translated. (In Iron and Coal Trades Review, Vol. 67, p. 1776.) New method consists in pressing of ingot from below, allowing gases to escape at the top. Sauveur, Albert, and Whiting, Jaspar. — Casting of pipeless ingots by the Sauveur overflow method. 1500 w. 111. 1903. (In Proceedings of the American Society for Testing Materials, Vol. 3, p. 129.) Segregation in soft steel ingots; its effect on rolled material as shown in tensile and shock tests. 2500 w. 111. 1910. (In Iron Age, Vol. 86, p. 730.) Gives results and conclusions reached by Wiist and Felser in paper in " Metallurgies Shows segregation to have greatest influence in shock tests, as segregated material is very brittle. Springer, J. F. — Piping in steel ingots; methods for its reduction and elimination. 4000 w. 111. 1909. (In Cassier's Magazine, Vol. 35, p. 426.) Springer, J. F. — Thermal treatment of steel ingots. 1200 w. 111. 1910. (In Scientific American, Vol. 116, pp. 262, 269.) Describes piping and segregation phenomena and briefly reviews methods for prevention. Stead, J. E. — Crystallization and segregation of steel ingots. 53 p. 111. 1906. (In Proceedings of the Cleveland Institution of Engineers, 1905-06, p. 163.) Review of work done on the subject, with conclusions. 420 STEEL RAILS Talbot, Benjamin. — Segregation in steel ingots. 44 p. 111. 1905. (In Journal of the Iron and Steel Institute, Vol. 68, p. 204.) Includes extensive tabulated data on the effect of additions of small amounts of aluminum to the ingot. Wahlberg, Axel. — Influence of chemical composition on soundness of steel ingots. 38 p. Ill 1902. (In Journal of the Iron and Steel Institute, Vol. 61, p. 333.) Wedding, H. — Untersuchung iiber den ursprung eines blasenraumes in einen flusseisenblocke 2000 w. 111. 1905. (In Stahl und Eisen, Vol. 25, Part 2, p. 832.) Considers probable origin of a blow-hole in a 2-ton ingot. Faulty shape of mould considered to be explanation. Weitere entwicklung des Riemerschen verfahrens zur herstellung dichter stahlblocke. 1000 w. 111. 1904. (In Stahl und Eisen, Vol. 24, Part 1, p. 392.) Illustrates great reduction in piping from use of new method of Riemer. Wickhorst, M. H. — Low-carbon streaks in open-hearth rails. 1200 w. 111. 1910. (In Proceed- ings of the American Society for Testing Materials, Vol. 10, p. 212 ) Studies rails that developed a peculiar kind of failure, shown to be due to streaks of metal low in carbon. Wickhorst, M. H. — Segregation and other rail properties as influenced by size of ingot 97 p. 111. 1911. (In Proceedings of the American Railway Engineering Association, Vol. 13, p. 655.) 33. Influence of Mechanical Work The principal points in connection with the rolling are given below: 1. Resistance to wear is a function of fineness of grain. 2. Fineness of grain is principally a result of mechanical treatment at proper temperature.* 3. Work done on steel above 950°-1050° C. (1742° F.-1922 F.) has less effect on changing the size of grain from the normal crystallization of the ingot than when the rolling is done at a lower temperature. Fig. 298 shows the steel entering the rolls. Figs. 299, 300, 301, and 302 illustrate views taken by Mr. Howard and show the gradual reduction of the bloom to the finished rail as it passes through the successive rolls. In 1909 a further investigation was made of the steel at different stages of the rolling by James E. Howard at the Watertown Arsenal. f In these tests, beginning with the ingot, the structural state of the metal was examined by taking cross sections and longitudinal sections. This method was carried through the various successive derivative shapes, and the results obtained are shown in the large number of illustrations which form the body of the report. The greater part of the work was devoted to Bessemer rail steel, five acid Bessemer heats being made for this series of tests, each heat furnishing six ingots about 19| by 20| inches at the bottom and about 5 feet high. One of the most important results of the tests was to throw light on the question of the amount of work or reduction necessary in rolling to develop the full physical qualities of the steel. Mr. Wickhorst draws the following * This should not be interpreted as meaning that resistance to wear is not a function of the chem- ical composition. t Tests of Metals, etc., 1909, Vol. 1 and Vol. 2, Government Printing Office, Washington. INFLUENCE OF DETAIL OF MANUFACTURE 421 STEEL RAILS conclusion from the tensile tests made of specimens taken at various stages from the ingot to the finished rail. s Section of 8 by 8 in. Rail Bloom Rolled from an Ingot 20 ins. Square. (Am. Ry. Eng. Assn. — Howard.) The results indicate that the metal in the walls of the ingot takes com- paratively little work or reduction to impart to it what may be called its full Fig. 300. — Rail from an Early Pass in Roughing Rolls, Rolled from Bloom Shown in Fig. 299. (Am. Ry. Eng. Assn. — Howard.) physical properties of tensile strength and . ductility. These are reached in the bloom, except at the top end. The axial metal at the bottom of the ingot also INFLUENCE OF DETAIL OF MANUFACTURE 423 Fig. 301. — Same Rail as Shown in Fig. 300 after Further Reduction. (Am. Ry. Eng. Assn. — ■ Howard.) soon reaches its full physical properties, but in the upper half of the ingot it must be carried well toward the finished rail before these properties are fully developed. Fig. 302. — Finished Rail from Same Ingot as Bloom and Pieces from Roughing Rolls. (Am. Ry. Eng. Assn. — Howard.) 424 STEEL RAILS Where the metal is of fairly even composition and free from sponginess, it reaches its full physical qualities of tensile strength and ductility at about ten reductions or a reduction to one-tenth of the original cross section of the ingot, but the interior portion of the upper part of the ingot requires twenty-five or more reductions to have its full physical qualities developed, that is, the cross- sectional area must be reduced below one twenty-fifth of its original amount. Table XCII gives the result of tests by Sauveur on the relation between the size of the grain and the physical properties of the same piece of steel.* TABLE XCII. — RELATION BETWEEN SIZE OF GRAIN AND PHYSICAL PROPERTIES OF STEEL Size of Grain. Tensile Strength. Elongation Per cent of Length. Reduction of Area, Percent. In 0.0001 Millimeter. Number per Approximately. Kilograms per Square Millimeter. Pounds per Square Inch. 148 118 62 44,000 54,000 104,000 69.6 70.3 77.7 99,000 100,000 110,000 15.0 19.0 22.5 20 22 35 Mr. Robert Job, chemist of the Philadelphia & Reading Railroad, states that " in a lot of over 75,000 tons of rail observed during a period of five years, we have 15 times as many fractures in service from rails of coarse grain, or 19,600 cells per square inch, as from rails of medium fine structure, 48,400 cells per square inch, and there is also a marked difference in capacity for wear in favor of the finer structure rail. Out of several thousand tons of rail now (1905) in our tracks, made with a clause in the specifications requiring more than 40,000 cells per square inch, only one rail has fractured in service, and that owing to pipes in the steel in process of manufacture." Dr. P. H. Dudley states that rails of 100-pound section with 48,000 to 70,000 cells per square inch after having sustained 250,000,000 tons in the track were still in good condition. The rolling tends to break down the grain and give a finer structure, but im- mediately after the work stops the grain commences to grow again, consequently the lower the finishing temperature the smaller the grain size. If the steel is worked below the critical point, strains are developed which injure the metal and may rupture it. Work at too low a temperature distorts the grain or flattens and elongates the crystals in the direction of the rolling. * N. Ljamin, Chem. Zeit, 1899, Baumaterialien, 1899, finds the tenacity in different steels varies directly as the size of the pearlite grains, at the same finishing temperature. INFLUENCE OF DETAIL OF MANUFACTURE 425 To thoroughly understand the effect of the rolling, it is necessary to study the structural changes that take place in the cooling metal.* Let us first consider the cooling curve of a copper bar, shown in Fig. 303. We find here no evidence of any sudden change in the nature of the cooling copper. V- V Freezing 20 40 60 Time Fig. 303. — Cooling Curve of Solid Copper. (J. W. Mellor.) '"0 20 40 60 Time Fig. 304. — Cooling Curve of Water. (J. W. Mellor.) If, however, a curve is drawn for water cooling down from 20° to -20° C, we get a terrace in the cooling curve, as shown in Fig. 304. This tells us that some change has taken place in the nature of the substance at 0°. We see at ■■ Fig. 305. — Recalescence. (J. W. Mellor.) once that this change corresponds with the passage of water from the liquid to the solid state. When a steel bar is cooling, an evolution of heat occurs at about 690° C. The amount of heat evolved is so great that the metal visibly brightens in color. The phenomenon is called " recalescence." The cooling curve is shown in Fig. 305. * See The Crystallization of Iron and Steel, J. W. Mellor, 1905. 426 STEEL RAILS The cooling curve of iron from the molten condition is shown in Fig. 306. The iron was practically pure, containing only .01 per cent of carbon. Osmond maintains that the existence of the transition points, Ar 3 and Ar 2 , in the cooling curve of the solidified metal points to the existence of three allotropic modifications of solid iron. Each critical point is found to be associ- ated with a change in the mechanical properties, the microscopic appearance, and the specific gravity of the metal. 1800°(— { 1 1 1 1 900°rr Freezing 860 vAr 3 750° %■ \ Ac, -^730° 69 \& vQ? 20 4-0 60 Time Fig. 306. — Cooling Curve of Iron. (J. W Mellor.) 20 40 60 Time Fig. 307. — Cooling and Heating Curves of Steel. (J. W. Mellor.) The changes which occur during the cooling of a substance are reversed when the substance is heated. The cooling curve of steel, with 1.2 per cent of carbon, shown in Fig. 307, is reversed on heating, as shown by the heating curve in the same diagram. The critical points on the heating curve of mild steel are generally a few degrees higher than the corresponding points on the cooling curve. Let us now consider what takes place when steel containing 0.6 per cent carbon cools from 900° C. The cooling curve shows nothing very remarkable until a temperature of about 720° C. is attained. Here the critical points Ar s and Ar 2 of pure iron coalesce into one. At this point pure iron, or ferrite, separates from the solid solution. The separation of ferrite goes on along the curve AP (Fig. 308) until the temperature reaches about 690° C, when another recalescence point occurs (An). No other essential change, as far as we are concerned, occurs as the system cools down to the normal tem- perature of the atmosphere. Fig. 308 is derived from Roozeboom's diagram,* the carbon-iron diagram, * H. W. B. Roozeboom, Zeit. Phys. Chem., 34.437, 1900; improved in Zeit. Elektrochem., 10.489, 1904; Metallographist, 3.293, 1900; H. le Chatelier, ibid., 3.290, 1900; 4.161, 1901; F. Osmond, 4.150, 1901; H. Jiiptner von Jonstorff, ibid., 5.210, 1902. INFLUENCE OF DETAIL OF MANUFACTURE 427 B A Ar>4 Pearlit^ Line Fig. 308. - - Cooling of "Solid Steel." (J. W. Mellor.) given by Howe,* based upon later researches, shows the temperatures some- what higher than those of the figure. When the temperature is above the line APB the iron is in a form known as "austenite." Whatever carbon is present is dissolved in this austenite, which is what is called a "solid solution" as distinguished from a mechanical mixture or conglomerate, just as salt and water, when brought in contact, merge in each other and pass from the condition 1200V of a mixture or conglomerate to that of a single substance. As the iron with 0.6 per cent carbon cools and the line AP is reached the austenite begins expelling from itself part of its iron in the form of ferrite. As the ferrite thus expelled is nearly or quite free from carbon, the remaining austenite be- comes relatively richer in carbon, until, when the temperature reaches An, it contains 0.9 per cent carbon which is the carbon content of pearlite. On cooling past this point all the austenite changes into pearlite, with no change in the ferrite which it has generated in the passage along the line AP, so that the steel now consists of a conglomerate of ferrite and pearlite. This conversion of the austenite into pearlite is accompanied by a considerable evolution of heat, and is shown by the recalescence curve of Fig. 305. Steels containing just 0.90 per cent carbon, and hence consisting of pearlite alone, are called "eutectoid" steels. Those containing less than this are called "hypo-eutectoid," and those more than this, " hyper-eutectoid " steels. As previously stated, work below the Ar x point distorts the grain or flattens and elongates the crystals in the direction of the rolling. The result of work above the Ar x point is to retard the growth of the grains. Howe f explains the relation between the temperature of the hot work and the size of the grain as follows: The mechanical distortion in rolling elongates these grains in the direction of rolling and shortens them in the plane of the pressure; this appears to throw the metal crystallographically into unstable equilibrium, with the result that *'Life History of Network and Ferrite Grains in Carbon Steel, H. M. Howe. Proceedings, American Society for Testing Materials, Vol. XI, 1911, p. 266. t H. M. Howe, Iron, Steel, and Other Alloys, 1903, p. 262. 428 STEEL RAILS the old grains thus distorted break up, and that the metal rearranges itself into new and equiaxed grains. But these new grains assume a size normal, not to the temperature at which the old ones had formed, but rather to the temperature now existing; during the rolling the temperature is constantly falling; each pass through the rolls tends more or less fully to break up the preexisting grain, and to substitute for it a new grain of a size more nearly normal to the now lower temperature. To speak more accu- rately, the new grain size approaches that normal for the existing temperature; but the result is much the same. For if each of a succession of passes through the rolls breaks up the existing grain, and substitutes for it a new one, then each new grain will be smaller than the preceding, because the normal towards which it tends is smaller than the normal towards which its predecessor tended at the higher temperature then existing. Fig. 309 attempts to express this condi- tion of affairs graphically. Here ordinates represent temperature and abscissae coarseness of grain. The line Ac±A may be taken as representing roughly the normal size of grain, D", which steel of given composition tends to assume with varying temperature, or the line of normal coarseness of grain. If the grain is smaller than the normal for existing tempera- ( Howe -) ture, it always tends to grow and to approach that normal. If it is coarser than that normal, it does not tend to shrink back towards the normal, except when the temperature is rising past Ac s . Let us suppose that we cease rolling a piece of steel while its temperature is at B, the mechanical work of the rolls having broken the grain down. During subsequent cooling the grain will grow, somewhat as sketched in the line BCE. If, however, we resume rolling when the grain has reached C, we will break down the grain, and drive it back, say to D. And so, keeping on, between passes the grain grows and the temperature simultaneously falls, while at each pass the squeeze which we give the metal breaks up the grain, and the curve of grain and temperature follows the zigzag line BCDG. I I P E Fig. 309. — The Influence of the Finish- ing Temperature on the Size of Grain. INFLUENCE OF DETAIL OF MANUFACTURE 429 If we cease rolling when the temperature has fallen to G, then the grain will grow as the metal cools, till the line of the actual size of grain intersects that of the normal size, the line Ac x A; with further cooling no further growth ensues, and the final size of grain is OP. If we had quenched the metal while at G, the final size of grain would have been OH. If we had ceased rolling when the temperature was at B, the final size of grain in the cooled steel would have been OE. Generally speaking, the grain size will be the coarser the higher the finish- ing temperature. Fig. 310 illustrates this principle. This shows the micro- structure of two like bars of the same steel, of which each had first been heated Cooled to 963° C. Cooled to 837° C. Fig. 310. — Influence of Finishing Temperature on the Size of the Grain of Steel of 0.50 per cent Carbon (Howe.) to 1394° C, then cooled slowly to the temperature indicated in the figure, then rolled, and then cooled slowly, so that these temperatures are the " finishing temperatures." Note how much coarser the meshes are in A, finished at 963° C, than in B, finished at 837°. Professor Sauveur's micrographs of rail structure show that in the section of a given rail, the network, or size of the walled cells, is the coarser the higher the temperature at which the rolling is finished.* According to Howe, when a piece like a rail, which is highly heated, is rolled with such heavy reduction as to distort the austenite grains greatly, the distorted and hence unstable grains immediately shatter, and their remains im- mediately begin growing again by coalescence. This is repeated as often as the piece is greatly reduced by the rolling. Each of the grains of austenite, formed by coalescence after the last of these reductions, in cooling down to the Ar t point, gives birth to a walled cell by ejecting to its outside the ferrite which it generates. Hence it is the size which these austenite grains reach after this last * Trans. American Institute of Mining Engineers, Vol. XXII, 1893, pp. 546-557, and especially Plates TV and V. 430 STEEL RAILS effective reduction that determines the network size of the cold steel, and as regards the opportunity for network growth, the finishing temperature is the equivalent of the highest temperature reached by objects not rolled. This well-marked network common to rail steels is probably due to their large manganese content, as otherwise, on account of their slow cooling, the ferrite would coalesce and break up the network.* -^ SIZE OF GRAIN Fig. 311. — Diagram of Results of Experiments on Rolling at Different Temperatures. This principle of governing the grain size by means of the finishing tempera- ture is of very great importance. In general, we should be inclined by considera- tions of economy of power to roll steel as hot as we dare, because the hotter it is the softer it is, and the less power is consumed in rolling. But this would natu- rally lead to a high finishing temperature, and thus to coarseness of grain and brittleness. Hence a high temperature is desirable as regards power consump- tion, but undesirable as regards the quality of the steel. f Fig. 311 shows graphically the results of experiments made at the Spar- * For illustration of this cellular structure in rails see Job, The Metallographist, Vol. 5, 1902, pp. 177-191; P. H. Dudley, ibid., Vol. 6, 1903, p. 111. t The Manufacture and Properties of Iron and Steel, H. H. Campbell, 1904, p. 410. INFLUENCE OF DETAIL OF MANUFACTURE 431 rows Point plant of the Maryland Steel Company. As in Fig. 309 ordinates represent temperature and abscissae coarseness of grain, the grain growing coarser from left to right. An ingot was rolled into blooms and two adjacent blooms, "A" and " B," were rolled into rails without further heating, the first, "A," being held before rolling in order to allow it to cool so that all work should be done at as low a temperature as possible, without, of course, reaching the lower critical point, while the second, " B," was rolled as quickly as possi- ble through all the passes, except the last, but was then held at the finishing pass If minutes; the result being that both pieces went through the finishing pass at the same temperature, which was about 750° C. (1382° F.). Fig. 312. — Rail "B" Near Surface, 46 Dia. — Campbell. Fig. 313. — Rail "A" Near Surface, 46 Dia. — Campbell. Fig. 312 shows " B " rail near the surface. Fig. 313 shows " A " rail near the surface. Fig. 315. — Rail 46 Dia. ■ Center of Head, Campbell. Fig. 314 is from the center of the head of " B " rail. Fig. 315 is from the center of the head of " A " rail. While Figs. 312 and 313 appear similar, Figs. 314 and 315 show the real difference between the two rollings. The last pass does very little work; there- 432 STEEL RAILS fore, holding the rail before the last pass does little good, except on the outer surface of the rail, and a low shrinkage or finishing temperature does not neces- sarily mean that the rail will have a good grain throughout. Fig. 318. — Side View at Top of Head, 70-lb. Rail, 50 Dia. (Am. Ry. Eng. Assn.) Fig. 319. — Side View at Center of Head, 70-lb. Rail, 50 Dia. (Am. Ry. Eng. Assn.) Figs. 316 to 321 presented by Wickhorst* illustrate the different grain found in the top and center of a new 70-pound Bessemer rail. A section about \ inch * Flow of Rail Head under Wheel Loads, M. W. Wickhorst, Am. Ry. Eng. & M. of W. Assn., Vol. 12, Part 2, 1911, p. 535. INFLUENCE OF DETAIL OF MANUFACTURE thick was taken from the rail and two pieces cut from it for microscopic test, as shown in Fig. 322. These pieces were polished on three sides, etched with Fig. 320.— Transverse View at Top of Head, 70-lb. Rail, 50 Dia. (Am. Ry. Eng. Assn.) Fig. 321. — Transverse View at Center of Head, 70-lb. Rail, 50 Dia. (Am. Ry. Eng. Assn.) 10 per cent solution of nitric acid in alcohol, and microphotographs made, mag- nified 50 diameters. Thus, horizontal, vertical transverse, and vertical longi- tudinal sections were obtained at the top and at the center of the head. There will always be some difference between the structure of the center of the head and the por- tion near the surface, but when the rail is rolled at a proper temperature during the passes, when considerable work is put upon the piece, this difference will not be serious. The effect of finishing temper- ature is not fully agreed upon, and many rolling-mill men feel that the properties of the steel depend quite as much on the amount of reduction in the rolls as upon the finishing temperature. Fig. 322. — Pieces for Microscopic Views shown in Figs. 316 to 321. 434 STEEL RAILS * To try to arrive at some conclusion in this matter, a number of tempera- ture readings were taken with both the Fery and Wanner pyrometers and checked against a thermo-couple at one or two large plants. For steel rails the finishing temperatures as indicated by the optical pyrometers averaged 1050 to 1100° C.;f for structural steel, 950 to 1000° C. And yet such material is not coarse-grained. (Reheating to such a temperature would give rail steel a very coarse grain.) A difference of over 100° C. in finishing temperature could not be detected in the size of grain, but a difference in section could very soon be noticed. Similar results can be reached experimentally by rolling out small sections at different temperatures. A section heated to 1300° C. and rolled out with 30 per cent reduction showed about the same sized grain as one heated to 1300° C, cooled to 900°, and rolled out, the finishing temperature being about 700° C. The question of rolling at a low temperature is one that has occupied the minds of engineers for a long time, and the fact that at present no solution has been made which is satisfactory to both the manufacturer and the consumer is evidence that it is not easily put aside. In rolling early rails it was recognized that mechanical defects would be de- veloped to a greater or less extent by the rolling process, and therefore the bloom, about 7 inches square, was conveyed from the blooming rolls to a steam hammer by which all visible cracks or defects were chipped out, care being taken to cut to the bottom of the imperfection, and not leave any pronounced shoulders at the edges of the resulting depressions; and until the adoption of automatically operated tables attached to the rail rolls, if the partially formed rails still showed defects, the operation of rolling was halted, while such places were chipped out by hand. These were usual practices, and were not abandoned because of their results being unsatisfactory, but on account of the time consumed and the expense incurred. In the formation of the grooves in the rolls much damage can be and often is done to the steel. With the object of increasing the product of a given mill, the ingot is rolled off at one heat, with heavy reductions in each pass so as to reduce the number of passes and consequently the time taken in rolling. It is interesting to turn to the following review of the English practice by Mr. Talbot: f " Our practice "s to take large ingots and have a furnace between * Some Practical Applications of Metallography, Campbell. Proceedings American Society for Testing Materials, Vol. VIII, 1908, p. 353. t These temperatures are from 100 to 200 degrees higher than the usual practice. t On Rail Steel as Manufactured by the Continuous Open-hearth Process, Talbot. Proceedings American Society for Testing Materials, Vol. VII, 1907. INFLUENCE OF DETAIL OF MANUFACTURE 435 the cogging and finishing mills,* which has the effect of acting as an equalizer so that the blooms are delivered to the finishing mill at an even temperature, making the bar more easily shaped, and the flange of the rail is sent out of the finishing groove at a temperature nearer to that of the head than has hitherto been possible. This, no doubt lessens the strains set up in cooling on the hot banks. Our practice is to increase the number of passes, decrease the amount of reduction per pass, and get the product by increased speed of the rolls and not by digging into and tearing the metal, as is done in the case where too few passes and heavy drafts are adopted. " With regard to rolling temperature, we may say we roll a 100-pound rail in lengths which give, after crops are cut off, three lengths of 10 meters. The first length is cut within 15 to 20 seconds after leaving the finishing groove of the mill, and on this we allow 7f inches shrinkage. The next length is cut within 35 to 50 seconds from leaving groove, and here 1\ inches is allowed. The third is within 60 to 80 seconds, and 7 inches is allowed for shrinkage. Of course these allowances only apply to 100-pound rails; less allowance is made in lighter rails." | At one of the large rail mills they formerly had a table on which the rails were held before they went through the finishing pass. The scheme of holding the rail before the finishing pass, where only a small amount of work is put upon the metal, as illustrated in Figs. 312, 313, 314, and 315, while giving a low finishing temperature, does not necessarily decrease the size of the grain. Starting with such a scheme as a basis and designing the rolling mill to hold the pieces to allow them to cool before the passes where the most work is done, and also arranging for the sorting out of the blooms to equalize the finishing temperature, would give a better arrangement and would have merit if applied to mills where the rails are finished too hot as a direct result of pro- ducing large tonnage. However, even with the most careful manufacture, a certain amount of heat on the bloom is necessary in order to take the A. S. C. E. sections through with the flanges properly filled out, and it will not be possible to reduce this temperature without the danger of the breakage of rolls, improper filling out of the flange, and additional strains in the steel, which are necessarily detrimental, unless the design is changed to make all parts of the section more nearly in balance as to the temperature of finish. An interesting experiment may be tried on a tee rail, which has been finished and straightened. Take 6 or 8 feet of rail and place it on a planing machine and cut the head off the web at the point where the web joins the head, and both * This is customary at a number of rolling mills in America. t Kennedy-Morrison Process. The Iron Age, December 20, 1900, pp. 16-18. 436 STEEL RAILS the head and bottom portion will spring out of a straight line, sometimes to a very marked extent, thus showing that great internal strains are there. This is a condition that cannot be avoided by the manufacturer without some help from the rail designer. The better distribution of metal in the new American Railway Association sections gives a rail that can not only be rolled at a lower temperature, but which is much less liable to injury in the straightening press. The rolling of these rails has developed some surprises. It was expected that the rails could be rolled at a lower temperature than the old sections, and that the shrinkage allowance could be reduced ; but it was found that under the same conditions the new section would require a greater shrinkage allowance than the old. The rails were unquestionably rolled colder than the old section, with the exception of the thin flange, but it was this thin flange that determined the shrinkage of the old rails. In going through the cambering wheels the head was stretched, giving the hot head a greater length for shrinkage than the base. In the new section the temperature is nearly uniform and much colder than the head of the old rail was, but no part of the new rail is as cold as the thin base of the old rail ; consequently a greater shrinkage allowance is required. At Gary* the ingots are bloomed to 8 by 8 inches in 9 passes and finished in 9 passes, making a total of 18 passes from ingot to rail. The reduction of the rail is from 400 square inches at the bottom of the ingot to 10.1 square inches, or a reduction of 39 times. The areas of the various passes, as furnished by the Steel Company at Gary, of their section 10030, which is the A. R. A. type " B " 100-pound rail, are as follows: Pass Number. Area. Pass Number. Area. Square Inches. Square Inches. Ingot 400 10 43.2 1 376.6 11 32.9 2 282.4 12 25.2 3 214.9 13 21.5 4 164.8 14 17.8 5 130.3 15 16.4 6 107.9 16 13.2 7 88.9 17 10.7 8 70.8 18 10.1 9 58.9 At the Maryland Steel Company f the blooms remain in the soaking pit about 1 hour and 25 minutes, and are rolled to 7| by 7f -inch blooms in 13 passes, the top end of the ingot forward, and turned after each two passes. The blooms k Report to Rail Committee, Proceedings Am. Ry. Eng. & M. of W. Assn., Vol. 12, Part 2, 1911, p. t Report to Rail Committee, Proceedings Am. Ry. Eng. Assn., Vol. 12, Part 2, 1911, p. 3 INFLUENCE OF DETAIL OF MANUFACTURE 437 are rolled directly into rails without reheating, in 11 passes, making a total of 24 passes from ingot to rail. The area of cross section in square inches in the various passes for the A. R. A. type " B " 90-pound rail, Maryland Steel Company, section No. 162, is about as follows: TABLE XCIIL- - REDUCTION OF AREA IN 90-LB. A. R. A. TYPE "B" RAILS ROLLED AT MARYLAND STEEL COMPANY (A. R. E. Assn.) Operation. Number of Pass. Area. *— ■ Number of Pass. Area. Operation. Number of Pass. w In ot Sq. In. 416 374 336 300 260 234 205 172 150 Blooming. Blooming. Blooming. Blooming. . Blooming. Roughing. Roughing. Roughing. Roughing. 9 10 11 12 13 1 2 3 4 Sq. In. 132 117 96 74 58 46.2 34.4 31.3 23.1 Roughing Roughing Intermediate... Intermediate... Intermediate.. . Intermediate... Finishing 5 6 7 8 9 10 11 Sq. In. 21.5 Blooming. . . Blooming... Blooming. . . Blooming. . . Blooming. . . Blooming. . . Blooming. . . Blooming. . . 1 2 3 4 5 6 7 8 17.8 16.0 15.2 12.3 9.7 9.0 Table XCIV presents data on American rolling-mill practice. Fig. 323 shows the arrangement of the rail mill of the Algoma Steel Company's plant. This consists of one 32-inch rev. bloom mill, three Seimens heating furnaces for reheating the blooms, and one 23-inch three-high rail mill. Plate XXX illustrates a reversing cogging mill and Plate XXXI and Fig. 324 three-high mills. The left hand illustration of Fig. 325 shows a set of rolls for use in a three-high mill, according to common English practice, in which the bottom and middle rolls are grooved to receive the rail, while the "closers" are on the middle and top rolls, and the guards to peel the bars out of the grooves rest by gravity on the bottom and middle rolls. In the American three-high mill, shown on the same figure, the top and bottom rolls are grooved and the middle roll serves as the "closer" for each of the others, itself carrying no grooves at all; to enable the bars to be got out of the top groove, the upper guard must be placed on the upper side of the bar as it issues from the roll, and as it will not lie there by gravity, the guard has to be kept up to the roll by a counterweight or spring, and is known as a balanced guard.* Fig. 326 shows the three-high rolls in the rail mill at Gary, f This mill is equipped with 12 sets or stands of roll trains, all operated at varying speeds by General Electric alternating-current motors, some of which are of the largest * Steel, by Harbord and Hall, London, 1911, p. 625. t Railroad Age Gazette, November 13, 1908, and The Iron Age, April 1, 1909. 438 STEEL RAILS TABLE XCIV. — DATA ON AMERICAN ROLLING-MILL PRACTICE (Compiled by Committee on Rail, Am. Ry. Eng. Assn., 1909, and revised by the author 1912) Number of 1 S ms3| Blooming Mill. Passes in fS . | |g£J Rail Train. g£ (2 c ./ Rail Mill. Location. !" .S ™ o s -J | 1 E Is If 1° - r - i ' llll Remarks. m. s. Sq. In m. s. Algoma Steel Co. Canadian Soo, Canada. m"xw t2 30 t8"X8" 19 8 3 30 Blooms reheated. tBethlehem Steel Bethlehem, 19"X23" 1 20 8"X8" 15 10 6 Ingots are reheated after Co. Pa. being taken from molds and are rolled direct with- out further reheating. "Cambria Steel Co. Johnstown, Pa. 20"X23" 8J"X10" 15 2 25.00 22 00 27 6 45 Ingots are reheated, rolled into blooms, again re- heated and rolled into rails. No rest is given prior to finishing pass. Carnegie Steel Co. Braddock, Pa. 18"X20" 9*"X9F 7 fl2 38.53 f20 4 41 Ingots are reheated, rolled into blooms, again re- heated and rolled into rails. Rails are given a rest immediately prior to finishing pass of from Carnegie Steel Co . Braddock, Pa. 16rX18i" 7 Old mill. Light rails 360 ' Rails not held between tCarnegie Steel Co. Youngstown, Ohio. Pueblo, Colo. 19"X21" 50 8'X8° 9 10 1 35 50 20 4 50 passes. Colorado Fuel & 20"X18" 17 7 5 29 Iron Co. tDominion Iron & Sydney, 18"X21" 17 10 28 Steel Co. Canada. ♦Illinois Steel Co. S.Chicago, 111. tl8"X19£' t50 8"X8" 9 4 5 32.89 18 Rails held 30 to 60 seconds before finishing pass. First rails shipped Feb. 26, Indiana Steel Co. Gary, Ind. 20"X24" 9 8 1 18 1909. •Lackawanna Steel Co. 'Maryland Steel Buffalo, N. Y. 19"X19" 2 45 8"X8" 6 4 5 49 5 15 6 5 No rest prior to finishing Sparrows Pt., 20"X21" 2 10 7|''X7r' 13 6 5 27 7 24 5 50 Ingots are reheated after Co. Md. being taken from molds and are rolled direct with- out further heating. No rest is given except that which occurs when bloom is being sheared. •Pennsylvania Steelton, Pa. 18| "X18^" 1 23 9 6 5 20 3 Steel Co. bria Steel Co.f tTennessee Coal, Birmingham, 19"X23" 1 15 8"X8" 13 5™ to 6"° Iron & R.R. Co. Ala. t Compiled by author. sizes ever constructed for industria service. These are housed in a separate bay, or lean-to, running parallel with the rolls. The rotors are 20 feet in diameter and have a speed of 83 revolutions per minute. All of the motors are connected directly to the roll trains by regular mill couplings. Although the motors are provided with flywheels and run in one direction, provision is made for reversing in case of necessity. The control system has been worked out with the greatest nicety, all operations being under the instant control of the operator by means of a master controller. The first group of rolls consists of four stands of continuous 40-inch mills, INFLUENCE OF DETAIL OF MANUFACTURE 439 440 STEEL RAILS •® "4 m Fig. 324. — Housing far 28-inch Three-high Mill. (Harbord and Hall.) English Three-high Rail Mill. American Three-high Rail Mill. Fig. 325. — Rolls used in Three-high Rail Mills. (Harbord and Hall.) INFLUENCE OF DETAIL OF MANUFACTURE 441 each two of which are driven by a 2000-h.p. motor. They are arranged in tandem, requiring no manipulation from stand to stand. Here, as elsewhere through the plant, sufficient distance is left between successive sets of rolls to enable a quarter turn of the ingot or bloom to be made, so that it is worked equally on all sides. The first two mills are equipped with 42-inch rolls, enabling 20-inch by 24-inch ingots to be used. After passing these four mills the ingot is sent to a 40-inch three-high blooming mill equipped with lifting sILiH Fig. 326. — Three-high Rolls in the Rail Mill at Gary. (Scientific American.) tables and arranged with a combined hydraulic and pneumatic balancing device. This mill, which is driven by a 6000-h.p. motor, gives the ingot five passes. After being bloomed the ingot is sheared in a 10-inch by 10-inch horizontal blooming shear, and the crop ends or butts are taken outside of the mill by a butt conveyor of unusual construction, which was designed and built by the engineers of the Indiana Steel Company. Each bloom then goes through a 28-inch roughing mill, which is three-high and equipped with tilting tables. This mill has three stands or rolls. The roughing stand, however, is the only one that is three-high, the other two stands being two-high. The mill is driven STEEL RAILS by a 6000-h.p. motor and gives the bloom three passes. After leaving the rough- ing mill the bloom goes through a two-high 28-inch forming mill driven by a 2000-h.p. motor, receiving but one pass. Then it is sent to finishing mills, which consist of five stands of 28-inch mills driven by two 6000-h.p. motors. After the dummy pass, the bloom is transferred to the first edging, which is in this same mill but the second stand, and turns back on an elevated table to the second edging, which is in line with the 28-inch roughing mill. It then travels by chain transfer to the lower tables and on the leading pass goes through FINISHING PASS £8"x69/*" k DUMMY ZB"x40" ?x ■ ■ BLOOMING PASS 40" x 90" 2N. D ROUGHING PASS 28" x 56" ROUGHING PASS 28"x60" Fig. 327. — Pass Diagram, Rail Mill, Illinois Steel Company, South Works. a stand, which is also in line with the roughing mill and driven by the same motor, and continues on to the third stand of the 28-inch finishing mill, this being the eighteenth and last pass. After the finishing pass the rail travels through to the saws, of which there are five provided, thus cutting four rails to length. These four rail lengths consist of half the ingot. As the capacity of this mill is 4000 gross tons per 24 hours, it will be seen that there must be a four-rail length sawed about every half-minute. The saws have 42-inch blades, arranged to be raised and lowered in unison by one controller from the hot-saw operator. The pass diagram of the rail mill at the South Works plant of the Illinois Steel Company is illustrated in Fig. 327. The Bessemer ingot is 18 inches by INFLUENCE OF DETAIL OF MANUFACTURE 443 -lH3^-<^^&-|^ r °£* o<> 3= LD £ $ 444 STEEL RAILS 19| inches, the heating capacity is 192 ingots (24 single-hole pits). The ingot is worked direct to rail without reheating. The blooming mill is 40-inch pitch diameter three-high, and the ingot is given 9 passes and reduced to an 8-inch by 8-inch or 8-inch by 8^-inch bloom. The number of rail lengths rolled are three and four. The finishing mill consists of one stand 28-inch P. D. three-high first rough- ing rolls, one stand 28-inch P. D. two-high second roughing rolls, one stand 28- inch P. D. two-high dummy rolls,one stand 28-inch P.D. three-high finishing rolls. The number of passes from ingot to rail is as follows: Passes. Blooming 9 First roughing 3 Second roughing 1 Finishing 4 Total 18 Fig. 328 presents the general arrangement of the rail mill. Table XCV shows the shrinkage allowed by American rail mills and Fig. 329 the lengths of saw runs. TABLE XCV. — SHRINKAGE ALLOWED BY AMERICAN RAIL MILLS (Compiled by Committee on Rail, Am. Ry. Eng. Assn., 1909, and revised by the author 1912) No. of Rail Mill. Location. Time of Saw Shr nkage Allowed by Mills on 33-foot Rails. 70 75 80 85 90 95 100 1 Algoma Steel Co. . . . *Bethlehem Steel Co. *Cambria Steel Co. . . Carnegie Steel Co. . . Carnegie Steel Co. . . Carnegie Steel Co. . . Colo. Fuel & Iron Co. Dominion Iron & . Steel Co ♦Illinois Steel Co Indiana Steel Co. . . . *Lackawanna Steel Co ♦Maryland Steel Co... ♦Pennsylvania Steel Co Tenn. Coal, Iron & R.R. Co Canadian Soo, Canada. Bethlehem, Pa Johnstown, Pa 35 20 17-19 12-14 12-17 32 17 10-20 16 26 5 27 6| 6i 6& 6i 6& ' 61 ' 2 3 4 6 5f 6iV 6i 61 6A 61 51 6| 5 Braddock, Pa Youngstown, Ohio. . . . Pueblo, Colo 7! 6 6^ ' 6 " 6£ 6f 6& 6 6| 6| 6! 6} 6J 6A 6| 5J 6| 6H 6A 6f 61 6| 6f 61 7 8 Sydney, Canada South Chicago, 111. . Gary, Ind Buffalo, N. Y Sparrows Point, Md. Steslton, Pa Birmingham, Ala 6* 6A 9 10 6& 6A 61 6 6| 61 11" 12 13 14 6* 6 6| Note. — Information from R. W. Hunt & Co., except that marked (*), wh seconds consumed from the time rail leaves finishing rolls till ss s obtained direct from manufacturers by the After leaving the saw the rails pass through the cambering machine and are given a head sweep (Fig. 330) of from 3 to 8 inches, the A. S. C. E. section INFLUENCE OF DETAIL OF MANUFACTURE SAW RUNS 2 I 2 RAIL STOP +-H ^_^_ 143- 9" SAW NO. 1 1 -b^f" - 193'- 3%- SAW NO. I | ,1 RAIL STOP — 105- O" SAW NO, H- I RAIL STOP — 107-0" — SAW NO. I 197"-0"- SAW NO. I SANA/ NO.I I 21 .31 il Is I 3ll is I 3IRAILSTOP —212-0" SAW NO. I 24K-0" 3Q'AND 6Q'R *H— *!- I 69 -O" — >• SAW NO.I I 2 I 5 I < | I6 '_ B " __^| I |- Fig. 329. — Saw Runs of American Rail Mills. (See Table XCV for number of mills.) requiring a greater ordinate than the A. R. A. rails. The rails then pass to the hot beds and after being allowed to cool are transferred to the gagging or cold- straightening presses (Fig. 331). Fig. 330. — Head Sweep. In the heavier A. S. C. E. sections the gagging or straightening of the rail after it leaves the rolls and is cooled in the hot beds tends to develop injurious strains in the base and web. In some of the most modern English plants the 446 STEEL RAILS rails are run while still hot through straightening rolls, thus much reducing the labor of final straightening.* Fig. 331. — Cold Straightening Press, Maryland Steel Company. After straightening, the rails are inspected, drilled, reinspected, and loaded on cars for shipment. Many rails were formerly damaged in loading, but at several mills the use of a magnetic crane is now employed for loading the rails. The brand on rails gives the name of the manufacturer, a number or abbrevia- tion by which the rail section is designated, the month and year of manufacture, * S. von Schukowski schienen im katten und vocates straightening rails while still hot. Das richten von eisenbahn- zustande. Stahl und Eisen, Vol. 27 (1907), Pt. 1, p. 797. INFLUENCE OF DETAIL OF MANUFACTURE 447 and, if the metal is open-hearth steel, the letters " 0. H." are also added. Some- times the letters "F. T." are added to signify ferro-titanium steel. Square block letters and figures about one inch high are commonly used, and, as these are cut into one of the rolls of the last pass, the brand will always appear slightly raised at regular intervals on the web of the rail. The month is generally shown by Roman numerals, as VII for July, and sometimes by a series of I's, as IIIII for May. 1 ' 3 \ IO E ?>eo Q) 40 ^ 20 O 1 1 l" ■1 \ \ X •s \^-A V 20 23 HS ^ 21 " 1 00 IC 60 10 20 II 00 10 60 IC 20 9 30 1 OO 1060 I020 980 TEMPERATURE IN < Fig. 332. — Value of V/E for Tables XCVI, XCVII and XCVIII. The number representing the heat, blow or melt of steel, and the letter to indicate the position of the rail in the ingot is stamped on the web of the rail with dies while it is still red hot, but after it has been completely rolled and sawed to length. As the brand always appears in raised letters, and the heat number and letter is stamped on no confusion of the two should exist.* A series of experiments were made in Germany by Dr. Puppef to determine the power required to roll different sections. As this investigation presents many features connected with the design of the section and rolls and the effect of the temperature on rolling, it will be of interest to briefly review Dr. Puppe's work as it relates to the heavier weights of rails examined. The reversing mill on which these tests were made consisted of one cogging mill housing and three finishing mill housings. A flywheel converter set of the Ilgner system served to equalize the fluctuations of the power taken. The mill was driven by three motors rigidly coupled together, and connected in i * R. W. Hunt and Company, 1121, The Rookery, Chicago, 111., have published in convenient form full information in regard to the practice of branding and stamping at the different mills. t Experimental Investigations on the Power Required to Drive Rolling Mills, J. Puppe, London, 1910. See also for a full treatise of this subject Steel, Harbord and Hall, London, 1911, pp. 666-741. 448 STEEL RAILS series electrically; they had an aggregate output of 3600 H.P. normal and 10,350 H.P. maximum at a speed of 110 r.p.m. Tables XCVI, XCVII and XCVIII contain the results" of the tests with the heavier rails. The second line of the tables gives the time taken by the pass (in seconds) determined from the rise and fall of the current and power curves. Line 3 gives the time intervals (in seconds) between successive passes which were determined in the same way as the times of the passes. The time interval between the first and second passes is given in the column headed " pass 1," that between second and third passes in the column headed " pass 2," and so on. The last column contains the sum of all the figures in the preceding columns. 2 I k- 4 5 US r 1 ' i ~ X ~~ f 300 j < 260 * ( — 270—9 *-186—> Fig. 333. — Diagram of Cogging Rolls, Tables XCVI, XCVII and XCVIII, Dimensions in Millimeters. The energy given up, or stored by, the flywheel and other rotating masses was calculated from the speed curves and the moments of inertia. To arrive at the light-load loss, the average speed was determined, and the light-load loss was obtained by multiplying the power taken to drive the mill light at this speed by the time. The total work done in rolling the bar up to any pass is the sum of the work done in each individual pass up to that point, taking due account of the motor efficiency and leaving out the work expended in accelerating the moving parts or in light-load losses, copper losses, etc. Frequently, the section of the ingot during the first few passes could be determined only roughly, and then the length of the bar after the second or third pass was taken as unity, and the summation of the work done in rolling commenced correspondingly later. The areas of the cross sections of the bar or ingot were obtained wherever possible by cutting trial pieces off the bar, and measuring the area directly by a planimeter. It was not always possible to cut samples from the bars during the roughing passes, as the bar was too large for the bloom shears or hot saws, and in such cases the cross-sectional area was obtained from the scale showing the position of the rolls, while sections were cut from the bar in the last two passes, and the area measured as a check. It is often found that billets are STEEL RAILS I s "! K ;r iw'°l :2^S-g--^ .2 JVSjSg .._- s . --- = o 3 .^.Sol- -■■■:.■■ ■g > £ l- " - ! r - ; v ■ ■■■' SS 4 ^ | | % I g ., . : Q.5 tf : jl-a-lililiglil I _ „ li .a|S - *'| S8 8 a d-s If 1 lis fli I s s INFLUENCE OF DETAIL OF MANUFACTURE 455 §ISSI11 S =11 § ll3 S : • o >■ ° fc £ J §.— ' 2 Z* (v c e IjiIi|||IllillKlll|||l 456 STEEL RAILS rolled to different cross sections in the same grooves in the cogging mill, but this is because the position of the screwing-down gear is altered. The cross sections of the ingot in each pass with the reversing cogging mills were determined from the position of the top roll. A special pointer was fixed to the top roll, which indicated the position of this roll on a vertical scale pro- vided for the purpose. The length of ingot or bar was calculated from its cross section and weight. The crop ends were frequently cut off by bloom shears after the roughing passes, in which case a corresponding allowance was made in the calculations for the finishing passes. Fig. 335. — Sections in which only "Direct Pressure" occurs in the Process of Rolling. (Puppe.) The elongation was calculated from the cross sections and the lengths, such calculations often being based on the cross section after the second or third pass, in order to obtain greater accuracy, as already mentioned. The " volume dis- placed " is obtained by multiplying the reduction in cross section by the length of the billet before the pass in question, i.e., (Q x - Q 2 ) X L qi , where Qi = the cross section of the ingot or billet before the pass, Q 2 = the cross section after the pass, and L Qi = length of billet before the pass. In rolling there are two means by which the pressure is applied to the bar, viz., " direct " and " indirect " pressure. By direct pressure " is meant pressure which exists between the surfaces of two rolls, as, for example, with rolls grooved as shown in Fig 335. The term ' indirect pressure " will be used to denote the pressure usually existing between the groove sides of one and the same roll, which produces principally a reduction in a horizontal direction (width) and not in a vertical direction (height), as is the case with the sections shown Fig. 336. — illustration of "indirect in Fig. 335. The following example will make Pressure." (Puppe.) this dear: If the flange of a rail (Fig. 336) be pressed in such a manner that its thick- ness a-b and a'-b' is reduced, then this must be due to indirect pressure along the whole line from c to d and c' to d'. It will be noticed that indirect pressure INFLUENCE OF DETAIL OF MANUFACTURE 457 takes place here both between the sides of the groove of the same roll as also between the two rolls. Where the particles move solely in an axial direction along the bar, the energy required to accomplish this displacement is directly proportional to the product (Qi — Q 2 ) X L qi , in which Qi and Q 2 represent the cross sections of two consecutive passes, and L S1 the length of bar corresponding to the cross section Qx. For shortness, we will denote this product, which represents the volume displaced, by V. The fraction - - Qg) X Lq, (in cu. mm.) depends on the work done in rolling (in m. kg.) plasticity of the material, and, therefore, to a large extent on the temperature. By plotting a curve with the above fraction calculated for each pass as ordi- nates, and the corresponding temperatures as abscissae, we can obtain from this the number of cubic millimeters of material which will be displaced per m. kg. at various temperatures. Let us now investigate the case in which the particles of the metal do not move mainly in an axial direction along the bar, but also at right angles thereto. A simple example is that of a bar which is flattened out by rolls having no grooves to restrict the movement sideways. The angle of incision into the bar should be such as not to cause excessive spreading. Incisions at acute angles naturally cause greater spreading than incisions at obtuse angles, but very often the proper form at the first passes can only be obtained by incision of the bar at an angle from about 40° to 60°,* in which case a considerable amount of lateral spreading cannot be avoided. It is then advisable to facilitate lateral spreading and not to hinder the movement too much by the sides of the grooves. When designing rolls, successive profiles should be arranged in such a way as to obtain a smooth curve for V/E free from such sudden jumps as occur, for instance, in the curves in Fig. 332. It need hardly be said that the rolling of simple sections, such as flats, squares, rounds, etc., requires less power than the more compli- cated rail sections in which the flow of the metal is brought about by indirect pressure, and where the loss due to friction against the sides of the grooves is great. This loss should, of course, be kept as low as possible, and equally dis- Fig. 337. — Effect of Inclination of Inner Surface of the Rail Flange on Energy re- quired in Rolling. (Puppe.) ' Bartholme, Stahl und Eisen, 1907, p. 58. 458 STEEL RAILS tributed amongst the various passes. It can be reduced to a minimum by making the angle oo (Fig. 337) as small as possible, so as to obtain a large com- ponent a. From the point of view of economy in energy consumption when rolling rails, it is very desirable that the inner surfaces of their flanges be inclined as much as possible. If, however, the inclination of the inner surfaces, or the thickness of the finished flange, has been fixed, the amount of indirect pressure required for the formation of the flange can be reduced to a minimum by working it as thin as possible at the first forming pass. To sum up, the power required for complicated sections is greater than for simpler sections of the same final cross-sectional area, but this extra power depends to a very large extent on the skill with which the rolls are designed. If the rolls have the most favorable shape, the values for V/E for the various passes will be consistent with one another. Plate XXXII contains curves which are calculated from the tests. The shaded areas represent the energy supplied by the motors to the mill, and cover, therefore, not only the work required for actual rolling, but also the power required for running the mill light and for accelerating. The power taken by the cogging mill generally increases towards the end of the pass, owing to the acceleration of the rotating masses and the increase in the no-lead losses. The same holds good for a few of the roughing and finishing passes. At the last passes, however, the power taken decreases when the maximum speed has been attained, and the rotating masses are no longer accelerated. The peaks at the beginning of the curves for the last passes are due to this cause. The relatively high peak in the lower curve for pass No. 23 may be explained by the fact that maximum speed was reached in a very short time, as indicated by the sharp rise in the speed curve. The speed curve (Plate XXXII) usually drops rapidly when the ingot enters the rolls, and sometimes it even falls to zero, and then rises again. Frequently the speed increases suddenly at the end of the pass, especially in cogging mills. These irregularities in speed are due to careless manipulation of the driver's lever. In reversing mills the kinetic energy of the rotating masses is seldom used to assist the motor, but it does happen occasionally. From the acceleration curve (Fig. 338), it will be seen that a very large amount of energy is required to accelerate the rotating masses of a reversing mill; for instance, about 5300 h.p.-minutes are required to bring the rotating masses of this reversing mill up to a speed of 120 r.p.m. Assuming that the average speed is only 80 r.p.m., and that there are 20 passes, this means that INFLUENCE OF DETAIL OF MANUFACTURE 459 48,000 h.p.-minutes are expended in accelerating the rotating masses per ingot. This is a large percentage of the total energy required for rolling. It must be noted, however, that in the case of electrically driven reversing mills the energy expended in accelerating the rotating masses is largely returned again in the form of electric energy when the speed decreases, so that the net amount of energy required for acceleration purposes is not considerable. Where reversing 1 11 11 1 1 II 1 HI 11 II 1 1 H 1 1 1 1 ~1 t j / 7 _r 1 r I z _J ~l_ « I J. J f * 7 1 _f / / ^ r ~ /- <— X y jf~ , <^ ^ n x 5 ^ /7— -=— "'^ is per Minute. - Work done in Accelerating the Rotating Masses in Reversing Mil) (Puppe.) steam engines are employed, however, the work done in accelerating the rotating masses is lost, and this should be borne in mind when deciding whether for a given mill a reversible engine or a flywheel engine is best. Rails after becoming so worn in the track as to be unfit for further service may be rerolled into new sections. A considerable tonnage of such rails has been re- rolled by the McKenna process at a cost of about $7.00 per ton. The advantages claimed for this process are: First. That the worn rail is selected material, as the imperfect rails have been eliminated to a large extent during the time the rails have been in service. 460 STEEL RAILS Second. The rerolling puts additional mechanical work upon the material, which should improve its quality. The practical difficulties in connection with the process may be summarized as follows: First. The rail must not be worn beyond a certain degree, as there must re- main in the head of the rail a sufficient amount of metal to form the new head. The metal from the base and flange cannot be made to flow into the head to make up for its worn condition. In general it is not desirable to remove rails from the main track, which show only the amount of wear best adapted to rerolling; how- ever, when it is necessary to remove rails from some cause other than reduction of section on account of wear it may prove economical to reroll them into sections of lesser weight. Second. It is desirable that the rerolled rails may conform to standards already in use. This seems to be in a practical way difficult to accomplish, owing to the varying shape of the head of the rerolled rail, as the rail is much or little worn. The following figures are taken from a record of a mile of 80-pound rail rerolled by the American McKenna Process Company. 10,560 ft. of rail taken out of track Tons. Weight when new 125 .71 Loss in track after 10 years' use 5 . 33 Weight sent to mill 120 .38 10,151 ft. of rail received from mill 103 .20 Scrap received from mill 17 . 18 The sections given in Fig. 339 and Plates VII and VIII of the rails used Pennsylvania, 100-lb. Pennsylvania, 85-lb. Fig. 339. — Recent Rail Sections. (Railroad Age Gazette.) INFLUENCE OF DETAIL OF MANUFACTURE 461 I* 2 J2 *| Canadian Pacific, 85-lb. Baltimore & Ohio, 90-Ib. K- -2k M Santa Fe, 85-lb. Burlington, 90-Ib. Section. Area of Head, Web, Base. Total, pCTcen . 42.2 36.8 37.0 36.2 per cent. 18.6 17.8 22.2 22.8 24.0 P 40 Ce 4 ' 40.0 ' 41.0 40.2 39.8 ioo 6 100 100 Santa Fe, 85-lb 100 Burlington, 90-lb 100.0 Fig. 339 (continued). — Recent Rail Sections. (Railroad Age Gazette.) 462 STEEL RAILS at the present time show clearly the willingness on the part of the railroads to meet the criticism of the manufacturers in regard to the faults in the design of the heavier A. S. C. E. sections. These new thick-base sections, adopted after the studies of 1907, cool with less curvature than the former thin-base types and require less cold-straighten- ing. There appears to have been a material reduction in the number of base failures in the new sections as compared with the A. S. C. E. design. A number of students of this subject think that there is room for still further improvements along this line to eliminate to an even greater extent the failures in the base of the rail. This is evidenced by the new Chicago and North-Western section for 100-pound rail in which the base is ff inch thick at the outer edge. Dr. P. H. Dudley has designed a new section giving to the fillet between the base and the web a radius of 1 inch. The Illinois Steel Company at its South Works plant is also experimenting with a new section of 110 pounds in weight which is similar to that used on the foreign railways in that the upper surface of the base is broken at two angles. CHAPTER VII RAIL SPECIFICATIONS 34. Comparison of American Specifications The rail committee of the American Railway Engineering and Maintenance of Way Association revised their specifications in the latter part of the year 1909; these were subsequently withdrawn and in March, 1912, the committee presented to the American Railway Engineering Association, which was now the name of the association, specifications for carbon steel rails. Some paragraphs, such as those relating to carbon under remarks in Table XCIX and Nos. 14 and 15, relating to physical requirements, were not considered as final, it being thought that the committee did not have sufficient information in its possession to make these sections in the specifications mandatory. The re- quirements in section 14 for ductility were somewhat lower than some of the members thought desirable. Paragraph No. 15, referring to deflections as a method of classifying rails, is also tentative, and it is the intention, when suffi- cient data is at hand, to prescribe maximum and minimum limits for deflections under the drop test. The committee will continue its investigations and the specifications in these respects will be subject to change. On January 10, 1912, the Pennsylvania revised its specifications for Bessemer and open-hearth rails. On January 1, 1909, the Association of American Steel Manufacturers issued standard specifications for Bessemer and open-hearth rails. These rail specifications, adopted by the steel manufacturers of the United States and Canada, which are practically the same for the different companies, indicate the views of the rail makers as to the proper tests and chemical composition for securing good rails. The A. S. C. E. sections are still officially regarded as standard practice. Standard specifications for Bessemer and open-hearth steel rails were adopted by letter ballot on August 16 1909, by the American Society for Testing Materials. In October, 1909, the Harriman Lines adopted standard specifications for Bessemer and open-hearth steel rails; the open-hearth specifications were subse- quently revised in February, 1910. 464 STEEL RAILS The above specifications show the development during recent years of rail specifications in this country and an examination of their requirements will prove of interest. The American Railway Engineering Association specifications of 1912 reflect the latest thought and are noticeable for the increase in the number of physical tests over those required in earlier specifications. A great many defects, such as piping of the ingot, can be adequately guarded against by proper physical tests, and in general it would appear desirable to leave the producer free in such cases to adopt his own methods of manufacture. Within certain limits, however, the specifications may well be drawn to exclude practice which is known to result in defective material. The desirability of doing this is emphasized by the great difference in quality found in rollings from different mills and in some cases for rails from the same mill, but rolled in different years. The specifications given in Article 35 are a good example of specifications drawn with a view to eliminating defective practice at the mill. The trend of recent specifications is to increase the amount of inspection which is being given the rail at the mills. The plan of the R. W. Hunt and Company of placing inspectors throughout the mill to watch the entire process of manufacture is evidence of this. Inspection Am. Ry. Eng. Assn. : 1. Inspectors representing the purchaser have free entry to the works of the manufacturer at all times while the contract is being executed, and shall have all reasonable facilities afforded them by the manufacturer to satisfy them that the rails have been made in accordance with the terms of the specifications. 2. All tests and inspections shall be made at the place of manufacture, prior to shipment, and shall be so conducted as not to interfere unnecessarily with the oper- ation of the mill. All of the specifications are substantially the same as the above. Material Am. Ry. Eng. Assn. : 3. The material shall be steel made by the Bessemer or open-hearth process provided by the contract. The clause in reference to material in the Pennsylvania Specification is the same, but in the other specifications it is omitted and a separate specification written for each class of material, i.e., Bessemer or open-hearth steel. RAIL SPECIFICATIONS 4G5 Chemical Requirements Am. Ry. Eng. Assn.: 4. The chemical composition of the steel from which the rails are rolled, de- termined as prescribed in Section 7, shall be within the following limits: (See Table XCIX.) Table XCIX presents a comparison of the chemical requirements of the different specifications. The Committee on Standard Rail and Wheel Sections of the American Railway Association, in its report of March 23, 1908, to the association, stated : " In the matter of chemistry specifications for Bessemer steel rail, statistics were obtained from the officers of the Ore Producers' Association which con- vinced the committee that it would be impossible for the mills to furnish more than a small percentage of the total rail requirements of the railways with a phosphorus specification less than .10. " The optional specification for .085 phosphorus prepared by the joint committee of manufacturers and railway men is now in the hands of all members, and is, therefore, available for use by those who are able to obtain low-phos- phorus Bessemer rails. It is not considered proper, however, to require less than .10 phosphorus in a specification intended for general use. Members desiring to obtain' a low-phosphorus rail will have the further option of using open- hearth steel. The committee conferred with a number of disinterested experts on the phosphorus question, and among the principal authorities consulted were William Metcalf, of Pittsburg, Robert Forsyth, of Chicago, and Henry M. Howe, of Columbia University. These gentlemen all agreed that it would be unreasonable to require less than .10 phosphorus in a specification for Bessemer rails intended to cover purchases for all American railways." The Pennsylvania specification for open-hearth rails makes the upper limits for classification A, phosphorus .03 and carbon .83; for classification B, .04 phosphorus and .75 carbon. The desired carbon for the two grades is .75 for the lower phosphorus, and .70 for the higher. The reason for making two classifications for open-hearth rails relates principally to the cost of manufacture. It was thought desirable to specify phosphorus as low as .03 so that high carbon could be used and the wearing quality of the rails, particularly on curves, would be materially improved. But the extra time required in the open-hearth furnace to reduce phosphorus from .04 to .03 results in some increase in the cost of manufacture, and a slight addition to the normal price per ton is added for the class A rails. STEEL RAILS 1 1 ion of Carbon for Low Phos- — When the material used mill is such that the average orus content of the ingot metal the Bessemer process is run- elow 0.08 and in the Open- process is running below 0.03, t seems mutually desirable, bon may be increased at the 0.035 for each 0.01 that the orus content of the ingot metal rerages below 0.08 for Besse- eel, or 0.03 for Open-hearth i! a Si j-stjl Ills! lllll |,|.a ill IK _ s H •XB M 1 •u !M 8 ■xb k S g s S !§ s s s c •m M -°_ ° _-, ,~°_ sss •XB M g •p.saa 6 •ai W do do' ood — — , — ~ ■~~~ § g •xb W cc •ni M 6 A 1 •xb W 2 s s 1 f^a. ■m M « 1 | •xb M d d d 3 •ai W B •xb W s o sss s H ° sss s s c •"!W ~°_ o ooo -°_ ■XBW ss s sax s gss § ■p.saa g d °« m §S§ § sss ui W ^2-, ^o_ooo 000 £ o 00008 s ss§ J S § S2 P | I b 1 1 fa* u 111 1 .9 a Jg|<±6§ 1 RAIL SPECIFICATIONS 471 I 1 Three test pieces shall be selected from each irelt at approximately equal intervals from the melt as poured. Two of these test pieces shall be tested, and if both meet the requirements, all the rails from the melt which they represent shall be accepted, provided they conform to the other re- ifications. Should both of these test pieces fail, all rails from the melt will be rejected. Should pieces fail, the'liini'sh-.ll be tested, and if this third test meets the require- ments, all the rails from 1 he melt shall be accepted the other requiieii enls of these specifications. Should the third lest fail, all the rails from the melt shall be rejected. One piece shall be tested from each heat of Besse- mer steel. If any rail breaks when subjected to the drop test, twoadditional tests will be made of other rails from the same blow of steel , and if either of these latter tests fails, all the rails of the blow which they rep- resent will be rejected; but if both of these additional test pieees meet the re- quirements, all the rails of the blow which they rep- resent will be accepted. & O «3 H al1 One piece shall be tested from each heat of Bessemer steel. (a) If the test piece does not break, all of the rails of the heat shall be accepted as No. 1 or No. 2 classification, according as the deflection is less or more, respectively, than the prescribed limit, provided that the test piece when nicked and broken does not show interior defect. (The words " interior defect " shall be interpreted to mean: seams, laminations, cavities or interposed foreign matter, made visible by the destruction test, the saws, or the drills.) (6) If the test piece breaks, or if the test piece does not break but when nicked and broken shows interior defect, all of the top rails from that heat shall be rejected. (c) A second test shall then be made of a test piece selected by the inspector from the top end of any second rail of the same heat, preferably of the same ingot. If the test piece does not break, all of the remainder of the rails of the heat shall be accepted as No. 1 or No. 2 classification, according as the deflection is lessoi more, respectively, than the prescribed limit, provided thai I he test piece when nicked and broken does not show any interior (d) If the test piece breaks, or if the test piece does not break but when nicked and bioken shows interior defect, all of the second rails from that heat shall be rejected. (e) A third test shall then be made of a test piece selected bv the inspector from the top end of any third rail of thesan e heal, preferably of ii. .-..,, ,,;>'"■ If the test piece does not break, all of the remainder of the rails of the heat shall be accepted as No. 1 or No. 2 classification, according as the deflection is less or more, respectively, than the prescribed limit, provided that the test i i ' 11 n i loes not show interior defect. (/) If the test, piece breaks, or if the test piece does not break but when nicked and broken shows interior defect, all of the remainder of the rails from that heat shall be rejected. Test pieces shall be selected from the second, middle and last full ingot of each open-hearth heat. (a) If two of these test pieces do not break, all of the rails of the heat shall be accepted as No. 1 or No. 2 classification, accoid- iti» as I he deflectioi is less or more, respectively, than the pre- scrihed limit, provided that these test pieces when nicked and broken do not show interior defect. (b) If two of the test pieces break, or if anv of the test pieces that have bee:: • ■-■--'. ,ui!n i he drop when nicked and broken si, on interior defect, all of the top rails from that heat shall be rejected. (c) A second test shall then be made from three test pieees selected by the inspector from the top ends of any second rails of the same heat, preferably the same ingots. If two of these test pieces do not break, all of the remainder of the rails of the heat shall be accepted as No. 1 or No. 2 classification, according as (he deflection is lessor more, respectively, than the prescribed limit , provided that the test pieces that have been tested under the drop when nicked and broken do not show interior defect. (d) If two of these test nieces break, or if any of the pieces that have been tested under the drop when nicked and broken show •'nterior defei 1 i id rulsof the heat shall be rejected. 0) A third test shall then he made from three test pieces selected bv the inspector from the top ends of anv third rails of the s.,i„e heat, preferably the same ingots. If two of these test pieces do not break, all of the remainder of the rails of (he heal shall be accepted as No. 1 or No. 2 classification, according as the deflection is less or more, respectively, than the prescribed limit, provided that the test pieces when nicked and broken do ||j fj"3 lis §ii 111 S?'Jj=; lirssfnirr Process Drop Tests: 17. One piece shall be tested from each heat of Bessemer steel. (a) If the test piece does not break at the first blow and shows the required elon- gation (Section 14), all of the rails of the heat shall be accepted, provided that the test piece when nicked and broken does not show interior defect. (6) If the piece breaks at the first blow, or does not show the required elongation (Section 14), or if the test piece shows the required elongation, but when nicked and broken shows interior defect, all of the top rails from that heat shall be rejected. (c) A second test shall then be made of a test piece selected by the inspector from the top end of any second rail of the same heat, preferably of the same ingot. If the test piece does not break at the first blow, and shows the required elongation (Section 14), all of the remainder of the rails of the heat shall be accepted, pro- vided that the test piece when nicked and broken does not show interior defect. (d) If the piece breaks at the first blow, or does not show the required elonga- tion (Section 14), or if the piece shows the required elongation but when nicked and broken shows interior defect, all of the second rails from that heat shall be rejected. (e) A third test shall then be made of a test piece selected by the inspector from the top end of any third rail of the same heat, preferably of the same ingot. If the test piece does not break at the first blow and shows the required elongai ion (Sec- tion 14), all of the remainder of the rails of the heat shall be accepted, provided that the test piece when nicked and broken does not show interior defect. (/) If the piece breaks at the first blow, or does not show the required elonga- tion (Section 14), or if the piece shows the required elongation but when nicked and broken shows interior defect, all of the remainder of the rails from that heat shall be rejected. 18. Test pieces shall be selected from the second, middle, and last full ingot of each open-hearth heat. (a) If two of these test pieces do not break at the first blow and show the re- quire 1 elongation (Section 14), all of the rails of the heat shall be accepted, pro- vided that these test pieces when nicked and broken do not show interior defect. (6) If two of the test pieces break at the first blow, or do not show the required elongation, or if am oi t he pieces t hat have been tested under the drop when nicked and broken show iniei ior deleci , all ol 1 he top rails from 1 hat heat shall be rejected. (c) Second tests shall then be made from three test pieces selected by the in- spector from the top end of any second rails of the same heat, preferably of the same ingots. If two of these test pieces do not break at the first blow and show the required elongation Section 11. all of i he remainder of the rails of the heat shall be accepted, pmvidod I hat. t he pieces t hat have been tested under the drop when nicked and broken do nol show interior defect. (d) If two of these test pieces break a I the first blow or do not show the required elongation (Section 1 1), or it anv of i he pieces thai have been tested under the drop when nicked and broken show interior defect, all of the second rails of the heat shall be rejected. (e) Third tests shall then be made from three test pieces selected bv the in- spector from the top end of an v third rails ol the same heal, preferably of the same ingots. If two of these test pieces do not break at i he first blow, and show the re- quired elongation (Section 14), all of the remainder of the rails of the heal shall lie uccepted, provided that the pieces that have been tested under the drop when nicked and broken do not show interior defect. (/) If two of these test nieces break ai the first blow or do not show the required elongation i sect ion 1 1 1, or il any ol t fie pieces ;lc, have been tested under the drop when nicked and broken show interior defect, all of the remainder of the rails from that heat shall be rejected. 472 STEEL RAILS being made in the United States is melted in furnaces of a minimum capacity of 40 tons, and the majority of it is made in 50-ton or 80-ton furnaces. The feeling is growing among railway engineers that present specifications do not go far enough in specifying tests of a certain number of ingots from each heat, but that specimens should be tested from each individual ingot. On account of the uncertainty attending the formation of the pipe in the ingot an increase in the number of tests per heat would appear desirable. The Pennsylvania is the only specification that provides for a limiting deflec- tion, although the American Railway Engineering Association give limits that it is desired not to exceed and state that it is proposed to prescribe the requirements in regard to deflection as soon as proper limits have been decided on. In the absence of a tension test it would seem desirable to make provisions for fixing maximum and minimum limits for the deflection. The American Railway Engineering Association specifications are the only specifications which call for a ductility test. This test has been used for some time by Dr. P. H. Dudley, as shown in the New York Central Lines specifications given in Article 35. No. 1 and No. 2 Rails Am. Ry. Eng. Assn. : 19. No. 1 classification rails shall be free from injurious defects and flaws of all kinds. 20. (a) Rails which, by reason of surface imperfections, or for causes men- tioned in Section 30 hereof, are not classed as No. 1 rails will be accepted as No. 2 rails, but No. 2 rails which contain imperfections in such number or of such char- acter as will, in the judgment of the inspector, render them unfit for recognized No. 2 uses will not be accepted for shipment. (6) No. 2 rails to the extent of 5 per cent of the whole order will be received. All rails accepted as No. 2 rails shall have the ends painted white and shall have two prick punch marks on the side of the web near the heat number near the end of the rail, so placed as not to be covered by the splice bars. All of the specifications state that "No. 1 rails shall be free from injurious defects and flaws of all kinds." The Pennsylvania specifications for No. 2 rails are the same as the above with the clause added that rails which exceed the prescribed limits of deflection in the drop test may be accepted as No. 2 rails. The manufacturers' specifications are somewhat different and are given below. Rails which, by reason of surface imperfections, are not classed as No. 1 rails RAIL SPECIFICATIONS 473 shall be considered No. 2 rails, but No. 2 rails shall not be accepted for shipment which have flaws in the head of more than \ inch, or in the flange of more than | inch in depth, and these shall not, in the judgment of the inspector, be, in any in- dividual rail, so numerous or of such a character as to render it unfit for recognized No. 2 rail uses. Both ends of No. 2 rails shall be painted white. The Harriman Lines specifications are the same as the manufacturers' with the additional clauses that No. 2 rails will be accepted up to 5 per cent of the whole order, and in common with the American Society for Testing Materials they will not accept rails as No. 2 from heats which failed under the drop test. Quality of Manufacture Am. Ry. Eng. Assn. : 21. The entire process of manufacture shall be in accordance with the best current state of the art. This section is common to all specifications except the manufacturers'. Bled Ingots Am. Ry. Eng. Assn. : 22. Bled ingots shall not be used. This is specified by all except the manufacturers', with an additional clause providing that the ingots be kept in a vertical position until ready to be rolled, or until the metal in the interior has had time to solidify. Discard Am. Ry. Eng. Assn.: 23. There shall be sheared from end of the bloom formed from the top of the ingot, sufficient metal to secure sound rails. The Pennsylvania requirements are the same as the American Railway Engineering Association, while the Manufacturers' specifications do not refer to this part of the process. The American Society for Testing Materials and the Harriman Lines speci- fications call for a definite discard as follows: A.S.forT. M.: There shall be sheared from the end of the blooms formed from the top of the ingots not less than x per cent,* and if, from any cause, the steel does not then appear to be solid, the shearing shall continue until it does. * The percentage of minimum discard in any case to be subject to agreement, and it should be recognized that the higher this percentage the greater will be the cost. 474 STEEL RAILS Harriman Lines: 1. (d) There shall be sheared from the end of the bloom and rail formed from the top of the ingot a total discard of not less than nine (9) per cent of the weight of the ingot, and if, from any cause, the steel does not then appear to be solid, the shearing shall continue until it does. If, by the use of any improve- ments in the process of making ingots, the defects known as " piping " shall be prevented, the above shearing requirements may be modified. On this system, by excluding the top, or A, rails from main-line use, the effect of an additional 30 per cent discard is obtained, and at the same time the discard is saved for use on sidings and other locations where second-hand rails usually are used; the road thus doing its own discarding beyond the manufacturers' allowance, and saving the product without risk to the quality of the main-track rails. In view of the uncertainties, as to the length of the pipe it appears that the position taken by the American Railway Engineering Association and the Pennsylvania System in their specifications is the most reasonable one, viz., to leave the discard to the manufacturers, and to safeguard the product by proper tests, especially by choosing the test piece from such a location, and making the rejections such, that it will be to the interest of the manufacturer to volun- tarily discard the metal which will not stand test. Am. Ry. Eng. Assn.: 24. The standard length of rails shall be 33 feet, at a temperature of 60 de- grees Fahrenheit. Ten per cent of the entire order will be accepted in shorter lengths varying by 1 foot from 32 feet to 25 feet. A variation of J inch from the specified lengths will be allowed. No. 1 rails less than 33 feet long shall be painted green on both ends. TABLE CI.— LENGTH OF RAILS IN STANDARD AMERICAN SPECIFICATIONS Specifications. Standard Lengths. Shorter Lengths that will be Accepted. Feet. 33* 30 or 33 30 or 33 33 33* Feet. 32, 31, 30, 29 28, 27, 26, 25 1 Varying by even > feet to twenty- ) four (24) feet. 30, 27|, 25 Manufacturers' A. S. for T. M * At a tempers ture of 60° F. All of the specifications agree in allowing ten per cent of the entire order to be shorter lengths than the standard and permit of a variation of I inch in length from that specified. All call for the short-length rails to be painted green on both RAIL SPECIFICATIONS 475 ends. The standard length and short lengths that will be accepted, however, vary, and the requirements given in the various specifications are shown in Table CI. Shrinkage or Control of Finishing Temperature Am. Ry. Eng. Assn.: 25. The number of passes and speed of train shall be so regulated that, on leaving the rolls at the final pass, the temperature of the rail will not exceed that which requires a shrinkage allowance at the hot saws, for a rail 33 feet in length and of 100 pounds' section, of 6f inches, and | inch less for each 10 pounds' decrease in section. .6* 6± MANU FACTUR A.S. FO ERS \ RT.MJ A.R.E.&. A.R.A.\ M.W.A, J 3^2 ^^ *^^ £+ ^ — A.S.C.E. TO 80 90 IOO WEIGHT OF RAIL. LBS. PER- YD. Fig. 340. — Shrinkage Allowed in American Specifications in 1909. 26. The bars shall not be held for the purpose of reducing their tempera- ture, nor shall any artificial means of cooling them be used after they leave the finishing pass. Rails, while on the cooling beds, shall be protected from snow and water. The other specifications are the same, except that in the Manufacturers' American Society for Testing Materials and Harriman Lines, the statement that rails, while on the cooling beds, shall be protected from snow and water, is omitted. A greater shrinkage is allowed in present specifications than was formerly the case. Fig. 340 shows the allowance of different specifications in 1909; it will be 476 STEEL RAILS noted that the shrinkage has been increased to agree with the higher figure given by the manufacturers. In the Pennsylvania requirements of that date, it was pro- vided that the shrinkage allowance be decreased at the rate of t }q inch for each second of time elapsed between the rail leaving the finishing rolls and being sawed. The A. S. C. E. specifications called for -gV inch in place of i| ¥ inch- The control of the finishing temperature by the amount of contraction which the rail undergoes in cooling from the finishing to the atmospheric temperature appears to be the only method practical to use. Other efforts have been made to determine the finishing temperature by the use of pyrometers and by the ex- amination of the microstructure of the rails. The use of pyrometers naturally suggested itself at first as the most promising means of accomplishing that pur- pose, but it was soon found that no pyrometric device existed which could be applied in a practical way to the detection of the temperature of quickly moving rails. The micro-test, although attractive and useful, can only be applied to a very small percentage of the rails manufactured, and this is its greatest weakness. Section Am. Ry. Eng. Assn.: 27. The section of rails shall conform as accurately as possible to the tem- plet furnished by the railroad company. A variation in height of ^ inch less or 3V inch greater than the specified height and T \ inch in width of flange will be permitted; but no variation shall be allowed in the dimensions affecting the fit of the splice bars. The other specifications are substantially the same as those given above. The Manufacturers' specify A. S. C. E. sections; the Harriman Lines, A. R. A. section "A" 90-pound, Railroad Company's "Common Standard" 75-pound, A. S. C. E. section, 65-pound; and the American Society for Testing Materials say, unless otherwise specified, A. S. C. E. sections. Weight Am. Ry. Eng. Assn.: 28. The weight of the rails specified in the order shall be maintained as nearly as possible, after complying with the preceding section. A variation of one-half of one per cent from the calculated weight of section, as applied to an entire order, will be allowed. 29. Rails accepted will be paid for according to actual weights. The other specifications are substantially the same as the above. RAIL SPECIFICATIONS 477 Straightening Am. Ry. Eng. Assn.: 30. The hot straightening shall be carefully done, so that gagging under the cold presses will be reduced to a minimum. Any rail coming to the straight- ening presses showing sharp kinks or greater camber than that indicated by a middle ordinate of 4 inches in 33 feet, for A. R. A. type of sections, or 5 inches for A. S. C. E. type of sections, will be at once classed as a No. 2 rail. The distance between the supports of rails in the straightening presses shall not be less than 42 inches. The supports shall have flat surfaces and be out of wind. All of the specifications are substantially the same. Drilling Am. Ry. Eng. Assn.: 31. Circular holes for joint bolts shall be drilled to conform accurately in every respect to the drawing and dimensions furnished by the Railroad Company. Substantially the same for all specifications. 32. (a) All rails shall be smooth on the heads, straight in line and surface, and without any twists, waves or kinks. They shall be sawed square at the ends, a variation of not more than one-thirty-second inch being allowed; and burrs shall be carefully removed. (&) Rails improperly drilled or straightened, or from which the burrs have not been removed, shall be rejected, but may be accepted after being properly finished. Substantially the same for all specifications. Branding Am. Ry. Eng. Assn.: 33. The name of the manufacturer, the weight and type of rail, and the month and year of manufacture shall be rolled in raised letters and figures on the side of the web. The number of the heat and a letter indicating the portion of the ingot from which the rail was made shall be plainly stamped on the web of each rail, where it will not be covered by the splice bars. The top rails shall be lettered "A," and the succeeding ones "B," "C," "D," etc., consecutively; but in case of a top discard of twenty or more per cent, the letter "A" will be omitted. Open-hearth rails shall be branded or stamped "0. H.* w All mark- ings of rails shall be done so effectively that the marks may be read as long as the rails are in service. The Pennsylvania specifications are the same as the above. 478 STEEL RAILS All of the other specifications omit the clause in the American Railway Engi- neering Association specifications in reference to omitting the letter "A" in case of a top discard of twenty per cent or more, but are substantially the same in other respects. The Harriman Lines specify that all "A" rails shall have the top of the flange at each end painted yellow, and the American Society for Testing Materials only require rails weighing 70 pounds per yard or over to be stamped with a letter to indicate the portion of the ingot from which the rail was rolled. Separate C Am. Ry. Eng. Assn. : 34. All classes of rails shall be kept separate from each other. Loading Am. Ry. Eng. Assn. : 35. All rails shall be loaded in the presence of the inspector. The Pennsylvania specifications are the same for both of the above clauses. The Harriman Lines specifications contain the following clause: The following classes of rail shall be loaded separately as far as practicable, excepting at the finishing of an order or the end of a rolling. In this case the differ- ent classes shall be kept separate by placing strips of wood between each class, and each shipping notice shall contain full information as to the contents of each car: No. 1 rails, B, C, D, etc., full lengths. No. 1 rails, B, C, D, etc., short lengths. No. 1 "A" rails; that is, rails from the top of the ingot, full length. No. 1 "A" rails, short length. No. 2 rails, all lengths. 35. Specifications (New York Central Lines) for Basic Open-hearth Rails i st — Chemical Composition: 80 Lb. 90 Lb. 100 Lb. .55 to .68 .70 to 1.00 .10 to .20 .04 .60 to .73 .70 to 1.00 .10 to .20 .04 .62 to .75 .70 to 1.00 .10 to .20 .04 To adjust the chemical composition to the special conditions of manu- facture at each mill, the engineer representing the railroad company, from the inspection of the ingots, their heating, blooming, and rolling into rails, shall have the right to select the lower or average limit of either the silicon or man- RAIL SPECIFICATIONS 479 ganese, or both, with the average carbon content as the working basis for mak- ing the steel, as he may find requisite for good setting ingots with freedom from pipes and rolling into tough steel by the plant of the manufacturer. 2nd — Process of Manufacture : The entire process of manufacture and testing shall be in accordance with the best current state of the art, and special care shall be taken to conform to the following instructions: (a) Excessive use of material thrown into the teeming ladle to set the stopper must be avoided. (6) The steel must be well deoxidized and the waste products eliminated before the ingots are teemed. (c) The steel must be made to set quiet by the chemical composition in the molds without the addition of aluminum, either in the ladle or molds. (d) Spattering the interior sides of the molds in pricking the melts and teeming the ingots to be avoided as much as possible. (e) Time must be allowed for the tops of the ingots to set without spray- ing with water. (/) The ingots should be stripped as soon as the metal caps over on top, then sent to the scales to be weighed, then sent to the reheating furnaces to be charged promptly, to avoid the cooling of the interior metal and thus check the large shrinkage which occurs in it from unnecessary loss of temperature due to delays. It has been found, in good practice, possible in this way to confine the interior shrinkage to 0.05 to 0.1 of one per cent per cubic foot of the metal of rail ingots. The total shrinkage of an ingot depends upon its volume, chemical composition and loss of temperature at the time it is charged, yet in fair practice it may be confined to such small limits that it is removed in the usual discard of the bloom. Piped rails come from cold ingots or those which have been unduly delayed before charging into the reheating furnace. (g) Cast Iron Cut Out of the Ingot Stools: Care to be taken in teeming the ingots to prevent cutting out of the cast iron of the stools or ingot molds by the falling stream of hot metal from the ladle, avoiding a frequent cause of carbon streaks found in the segregated steel of " split heads." The most disturbing factor of the small amount of ordinary segregation in rail steel is the diffused cast iron in some ingots cut out from the stools. (h) Ingots shall be kept in a vertical position on the ingot cars and in the reheating furnaces until their heat is equalized ready to be rolled. 480 STEEL RAILS (i) Bled ingots shall not be used. ("Bled ingot" — one from the center of which the liquid steel has been permitted to escape.) (j) There shall be sheared from the end of the bloom formed from the top of the ingot sufficient discard to secure sound rails. (All metal from the top of the ingot, whether cut from the bloom or the rail, is the "top discard.") (k) One-hundred-pound (100 lb.) rails not to be rolled from blooms exceed- ing three (3) thirty- three-foot (33') lengths in a continuous bar; eighty -pound (80 lb.), or lighter, rails in not over four (4) lengths of thirty -three feet (33 ') in a continuous bar, when inserted in the contract. 3rd — Shrinkage : The number of passes and speed of train shall be so reg- ulated that, on leaving the rolls on the final pass, the temperature of the rails will not exceed that which requires a shrinkage allowance at the hot saws for a 33-foot rail of 100 pounds section of 6f inches, and T V inch less for each five pounds decrease of section. No artificial means of cooling the steel shall be used between the leading and finishing passes, nor after the rails leave the finishing rolls; neither shall rails be held before sawing for the purpose of reducing their temperature. 4th — Drop and Ductility Tests : A drop test to be made of a crop from the top bar of the second, the middle and the last full ingot of the melt. The crop 4 to 6 feet long to be stamped with a spacing bar of six one-inch spaces on the base, head or side as desired. Each butt must show under a single blow of the drop, of 18-foot, for the 80-pound or 90-pound section, and 20-foot for the 100-pound section, at least six per cent elongation for one inch or five per cent each for two consecutive inches before fracture for acceptance of the melt. The crop or butt is liable to be chilled accidentally in entering the rolls several times, or it may be caused by other delays, and should it break under a single blow without showing the percentage of elongation specified, it shall "be considered as indicating deficient ductility or chilled metal, and the results must be rejected. The Inspecting Engineer representing the Railroad Company must then take a duplicate test from the same ingot at the top end of the "A " or " B " rail, according to the nine or greater percentage of discard, and the results taken in lieu of those from the first crop or test to determine whether or not the piece had the requisite ductility in accordance with the specifications. The distinction between a chilled test crop and those of inadequate ductility RAIL SPECIFICATIONS 481 must be ascertained according to above prescribed tests before rejections are made or rails accepted. Should any test piece under the first blow of the drop not break, but fail to show the percentage of elongation specified, the test piece shall be subjected in the same position to a second blow and the results so obtained govern in passing the test. The ductility of at least one specimen of each melt to be exhausted by one or more blows of the drop, and a record made of the respective elongations of each test. The drop-testing machine shall have a tup of 2000 pounds weight, the striking face of which shall have a radius of not more than five inches (5"), and solid supports, centers three feet (3') apart, for the test butts. The anvil block shall weigh at least 20,000 pounds and the supports shall be part of or firmly secured to the anvil. The report of drop test shall state the atmospheric temperature at the time the test was made. The testing shall proceed con- currently with the operation of the mill. The temperature of the test butts to be between 40 degrees and 100 degrees Fahr. 5th — Section : The section of rail shall conform to the dimensions fur- nished by the purchaser as accurately as possible consistent with the paragraph relative to specified weight. A variation in height of rails of 3V of an inch over or e 1 ? of an inch under, also yq of an inch in width of flange will be permitted, but no variation will be allowed in dimensions affecting the fit of the splice bars. 6th — Weight: The weight of the rail shall be maintained as nearly as possible, after complying with the preceding paragraph, to that specified in the contract. A variation of one-half of one per cent, from the calculated weight of sec- tion, on the entire order, will be allowed. Rails will be accepted and paid for according to actual weight. 7th — Length: The standard length of rails shall be thirty-three feet (33'). Ten per cent of the entire order will be accepted in shorter lengths varying as follows: Thirty feet (30'), twenty-eight feet (28'), twenty-six feet (26') and twenty -four feet (24'). A variation of f of an inch from the specified length will be allowed. Three rails in every 100 tons to be thirty-two feet and six inches (32' 6") long, the ends painted red, when inserted in the New York Central Contract. All other No. 1 rails less than thirty-three feet (33') long shall be painted green on both ends. 482 STEEL RAILS 8th — Branding : The name of the maker, the weight of the rail and the month and year of manufacture, together with "0-H," shall be rolled in raised letters on the side of the web, and the number of the melt and letter to desig- nate the position of the rail in the ingot shall be so stamped on each rail as not to be covered by the splice bars. When the rails are to be rolled with twenty per cent (20%) discard the first rail in the ingot shall commence with the letter "B," the second "C, " the third "D" and the fourth "E." When the "A" rails are to be taken they are to be loaded separately upon cars for shipment and the flanges at the ends painted yellow, when inserted in the contract. 9th — Drilling : Circular holes for splice bars shall be drilled in accordance with specifications of purchaser. They shall in every respect accurately con- form to drawing and dimensions furnished and shall be free from burrs. ioth — Straightening: Care must be taken in cambering the rails and with the hot-bed work, which must result in the rails being left in such con- dition that they shall not vary throughout their entire length more than four inches (4") for the "A. R. A." thick bases and not more than five inches (5") for the "DUDLEY" section or "A. S. C. E." sections from a straight line in any direction when delivered to the cold-straightening presses. Those which vary beyond that amount, or have short kinks, shall be classed as second qual- ity rails and be so marked. Rails while on the "hot-beds" shall be protected from coming in contact with water or snow. The distance between supports of rails in the gagging press shall not be less than forty-two inches (42"); supports to have flat surfaces. Rails shall be straight in line and surface and smooth on head when fin- ished — final straightening being done while cold. They shall be sawed square at ends, variations to be not more than ^ of an inch, and prior to shipment shall have the burr caused by the saw cutting removed and the ends made clean. nth — Inspection: The inspector representing the purchaser shall have free entry to the works of the manufacturer at all times while his contract is being executed, and shall have all reasonable facilities afforded him by the manufacturer to satisfy him that the rails are being made in accordance with the terms of the contract. All tests and inspection shall be made at the place of manufacture prior to shipment, and shall be so conducted as not to unneces- sarily interfere with the operation of the mill. The manufacturer shall furnish the inspector with a chemical analysis of RAIL SPECIFICATIONS 483 each melt of steel covering the elements specified in the section No. 1 hereof, and also report sulphur and copper. Analysis shall be made on drillings taken from small test ingots, the drill- ing being taken at a distance of not less than | of an inch beneath the surface of said test ingots. On request of the inspector the manufacturer shall furnish drillings for check analysis. 12th — No. 2 Rails : Rails which by reason of surface imperfections are not classed as No. 1 rails shall be considered No. 2 rails, but No. 2 rails shall not be accepted for shipment which have flaws in the head of more than | of an inch; or in the flange of more than \ of an inch in depth; and these shall not, in the judgment of the inspector, be, in any individual rail, so numerous or of such a character as to render it unfit for recognized No. 2 rail uses. 13th — Designation of No. 2 Rails and Short Lengths of No. 1 Rails : Both ends of all No. 2 rails shall be painted white. Both ends of all short lengths No. 1 rails shall be painted green, except the 32-foot and 6-inch rails, which are to be painted red. (Sgd.) P. H. DUDLEY, New York Central Lines. (Specifications of Oct. 1st, 1909. Revised Jan. 11th, 1911, to con- form to Manufacturers' sale per 100 pounds.) Note 1. "Process of Manufacture" (b): The elimination of the deoxidation products and impurities from the bath of metal is more important than has yet been appreciated. This prevents minute portions of the deoxidation prod- ucts from becoming entrained in the setting metal and therefore will avoid their being rolled in the steel, where in the rail head or base they would be subjected to alternate unit fiber strains under moving trains and contribute the needed factor to develop the interior transverse checks recently observed in a few rail heads. Time is required for the deoxidation products and impurities to rise after the steel is tapped into the ladle. These heterogeneous portions of the deoxidation products or impurities in the steel, as well as small flaws and interior cavities, are theoretically and practically known to be zones of weakness, and interrupt the normal unit strains and increase them in the surrounding metal, which often result in detailed fractures. Note 2. "Process of Manufacture" (/): The percentage of interior shrink- 484 STEEL RAILS Chemical Composition. Chemical Analysis. age per cubic foot of the metal of the ingots there mentioned was reduced the past year by good mill practice and well organized train service. The latter was to transport promptly the ingots after they were teemed and stripped so that they could be charged with the least possible delay into the reheating pits and then as soon as the heat of the metal was properly equalized, they were bloomed, which restricted the reduced cavity to the discard. Note 1 and 2 added for information. P.H.D. 1/3/12 36. British Standard Specifications of Bull Head Railway Rails (Report No. 9, Revised July, 1909.) Issued by The Engineering Standards Committee Supported by: The Institution of Civil Engineers; The Institution of Mechanical Engineers; The Institution of Naval Architects; The Iron and Steel Institute; The Institution of Electrical Engineers. (Reprinted by permission of the Committee) . 1 . The steel for the Rails shall be of the best quality made by the Bessemer, Siemens-Martin, or other process, as may be approved by the Engineer (or by the Purchaser). The Rails shall show on analysis that in chemical composition they conform to the following limits: Carbon from 0.35 to 0.5 per cent. Manganese " .7 to 1.0 " " Silicon not to exceed 0.1 " " Phosphorus " 0.075 Sulphur " " 0.08 " " 2. The Manufacturer shall make and furnish to the representative of the Engineer (or of the Purchaser) carbon determinations of each cast. A complete chemical analysis, representing the average of the other elements contained in the steel, shall be similarly given for each rolling. Such complete analysis shall be made from drillings taken from the rail or tensile test piece or pieces. When the rolling exceeds 200 tons, an additional complete analysis shal be made for each 200 tons or part thereof. Should the Engineer (or the Purchaser) desire to make independent chemical determinations, the necessary specimens and samples shall be furnished by the Manufacturer. For this purpose not more than two rails in every hundred tons manufactured shall be selected by representative of the Engineer (or of the Purchaser) and drillings taken with a drill of 2 inches diameter from the top of the head of the rail, unless otherwise specified by him, and if, upon being subjected to the specified tests, either fail to comply therewith, then all the Rails in the cast of which the test pieces form a part may be rejected. The representative of the Engineer (or of the Purchaser) may then take similar samples from a further two rails out of the same 100 tons, and should either fail to comply with the specified analysis the whole 100 tons may be rejected. In case of difference between the Engineer (or between the Purchaser) and the Manufacturer as to the accuracy of any analysis, either party shall have the right to have samples of the steel analyzed by an independent metallurgist, to be mutually agreed upon. The expenses attendant upon such independent analysis shall be borne by the party adjudged to be in the wrong. 3. Each Rail shall be made from an ingot not less than 12 inches square at the smaller and 14 inches square at the larger end, and must be cogged down into blooms, and sufficient crop then sheared from each end to ensure soundness. RAIL SPECIFICATIONS 485 All straightening shall be done by pressure and not by hammering. 4. A rolling margin of i per cent under to | per cent above the calculated permitted, but the calculated weight only will be paid for. Permissible will be Variation in Weight. TABLE OF GENERAL DIMENSIONS AND WEIGHTS OF (See Plate XIV) B. S." RAILS Number of "B.S." Sl.tI inn mill Nominal Weight per Yard in lbs. Height of Rail. Width of Head. of Rail. Pounds. Inches. Inches. Pounds per Yard. 60 4| 2A 59.79 65 4J 2f 64.58 70 5 2rV 70.13 75 51 2h 74.56 80 5| 2r 9 « 79.49 85 5M m 84.88 90 5fi 2f 89.77 95 5ft 2f 94.59 100 5ft 2| 99.84 General Dimensions of Rails. 6. Before the general manufacture of the Rails is commenced the Manufacturer shall, if required by the Engineer (or by the Purchaser), supply two sets of templates, internal and external, of approved material, for each " B. S." Section of Rail. Each template shall be suitably engraved with the Purchaser's name, the number of the " B. S." section (being the nominal weight of the Rail in pounds per lineal yard), the Manufac- turers' name and address, and the date of the Contract. These templates shall be submitted to the Engineer (or to the Purchaser) for his approval, and at the commencement of rolling the Engineer will have a competent person present to approve of the section. 7. Each Section of Rail under this Contract shall be accurately rolled to its respective template. 8. The whole of the Rails shall be of uniform section throughout, true to templates, per- fectly sound and straight, and free from splits, cracks, burrs and defects of every kind. 9. A quantity of short lengths will be taken in such lengths and quantities as may be ordered by the Engineer (or by the Purchaser), provided that these short lengths are cut down from longer lengths found to be defective at the ends only, and that the total quantity taken does not exceed 7 J per cent of the contract. N. B. — The Committee recommend the adoption of the following, as the normal lengths of Rails, viz. : — 30 feet, 36 feet, 45 feet, or 60 feet. 10. The Rails shall be the specified length at the temperature of 60° Fahr. No Rail will be accepted which is more than three-sixteenths of an inch (& inch) above or below the length specified, whether for curved or straight line. 11. When required by the Engineer (or by the Purchaser) rails are to be supplied from 1 to 6 inches shorter or longer than the normal specified lengths, and these special lengths are to have about one foot at each end painted with such colors as may be ordered. 12. Rails shall be supplied for switches and crossings when so ordered, and such Rails shall be of the required lengths and shall be cut from sound long Rails. 13. The Brand shall be rolled on the web of each Rail to show that the Rail is of British Standard Section and made under the conditions of this Specification; the number of the " B. S." Section (being the nominal weight of the Rail in pounds per yard), the process by which the Rails have been manufactured, the Manufacturer's name, initials, or other recognized mark, and the month and year of manufacture shall be rolled, in letters three-quarters of an inch (f inch) in size, on one Templates. Rails to Conform to Template. Rails to be Free from Defects. Length of Rails for Straight Line. Permissible Variation in Length. Rails of Special Length for Matching in Curved Line. Rails for Switches and Crossings. Branding. 486 STEEL RAILS side of the web of each Rail, e.g., \y B.S. 95, B.A.* 4.04; and the number of the cast or blow from which it has been rolled shall be stamped on the end of each Rail in half -inch (§ inch) block figures. 14. From each cast one rail shall be selected by the representative of the Engineer (or of the Purchaser). From this a piece 5 feet long shall be cut which shall be placed in a horizontal position with the bullhead uppermost upon two iron or steel supports resting on a solid founda- tion and placed so that their centers are 3 feet 6 inches apart, the upper surfaces of the supports being curved to a radius of 3 inches. The test shall comprise two blows delivered midway between the bearings from a falling iron weight of 2240 pounds, the striking face of which shall be rounded to a radius of not more than 5 inches. The heights of the drop for the various sections of Rails shall be as tabulated below. The blows must be sustained without fracture, and the Rail must show a deflection between the limits given below. FALLING WEIGHT TEST First Blow Second Blow Number of "B. S." Section and Nom- Drop. Deflection. Drop. Deflection. i'kiI Uemln nf Kails per Yard in lbs. From. To. From. To. Pounds. Feet. Inches. Feet. Inches. 60 5 1 1ft 10 3 3f 65 5 1 U 12 3 3f 70 6 1 1ft 12 3 3i 75 6 1 1ft 12 3 3J 80 6 1 1ft 15 3 4 85 6 1 1ft 15 3 4 90 7 1 11 20 3 4} 95 7 1 1ft 20 3 4J 100 7 1 1ft 20 3 41 Should the length cut from the selected Rail fail to comply with the test specified for its weight, two other Rails from the same cast will be selected and similar lengths cut and tested, and the acceptance or rejection of the cast will be decided by the result of the three tests, so that if two of the Rails selected fail to comply with the test, the entire cast will be rejected. 15. From each 100 tons of Rails the Manufacturer shall (if required by the representative of the Engineer or of the Purchaser) cut a test piece from any Rail selected as a sample Rail ; such test piece to be stamped to correspond with the sample Rail. It shall then be placed in a testing machine of approved pattern, and shall have an ultimate tensile strength equivalent to not less than 40 tons per square inch, nor more than 48 tons per square inch, with an elongation of not less than 15 per cent upon the Standard Test Pieces C or D (see Fig. 341). Should the test piece fail to fulfil these conditions, the representative of the Engineer (or of the Purchaser) may require the Manufacturer to test two other Rails from the same cast in the same manner, and the ac- ceptance or rejection of the cast shall be decided by the results of the three tests so that if two of the three Rails selected fail to comply with the test the entire cast will be rejected. The representative of the Engineer (or of the Purchaser) may then take similar test pieces from a further two rails out of the same 100 tons, and should either fail to comply with the test the whole 100 tons may be rejected. Should the Engineer (or the Purchaser) desire to have independent tests made, the Manu- facturer shall provide the necessary test pieces, viz., two for every 200 tons, properly shaped and prepared as described in Fig. 341. * The following abbreviations are recommended : S.A. Siemens-Martin Acid. S.B. Siemens-Martin Basic. B.A. Bessemer Acid. B.B. Bessemer Basic. RAIL SPECIFICATIONS 487 16. The holes for fishbolts must be drilled through the web from the solid at each end of Holes in RaiLs. the Rails, of the sizes and in the position shown in the British Standard specification for Fish plates for Bull Head Rails (Report No. 47) or on a drawing to be supplied by the Engineer (or the Purchaser). These holes must be clean and square with the web, without burrs on either side, and will be checked with the gauges to be furnished to the Manufacturer by the Engineer (or by the Purchaser). Should any of the holes vary from the correct size or position more than one thirty-second of an inch (^2 inch) the Rails in question will be liable to rejection. i u , DIA.= .564 IN. |i )§ ! AREA= V* SQ.IN. ! '« 2" GAUGE LENGTH ►» u PARALLEL FOR A LENGTH «, OF NOT LESS THAN 2 >/4" TEST PIECE C. 1 W \ 0IA.-.798 / W ! 1 AREA=HSQ 1 i J 1 L PARALLEL FOR A LENGTH OF NOT LESS THAN 3V«" _J TEST PIECE D. - Test Pieces C and D, British Standard S cifications of Rails. The gauge length and the parallel portion are to be as shown, the form of the ends to be as required in order to suit the various methods employed for gripping the test piece. 17. The Manufacturer shall give to the Engineer (or to the Purchaser), or his representative, Notice of at least seven clear days' previous notice, in writing, before the rolling of the first lot of Rails, Rolling to be and at least three clear days' previous notice, in writing, before the rolling of any subsequent lot Given - of Rails, is commenced, in order that arrangements may be made for the presence of the repre- sentative of the Engineer (or of the Purchaser) at the rolling. 18. The Engineer (or the Purchaser) or his representative shall have access to the works T nS p ect ion of the Manufacturer at all reasonable times. He shall be at liberty to examine the Rails during and Testing. any stage of their manufacture, and to reject any material or finished Rail which does not conform to the terms of this specification. Before the Rails are put before the representative of the Engineer (or of the Purchaser) for inspection the Manufacturer shall have them examined, and all Rail which he admits to be defective are to be sorted out and placed in a separate stack; the representative of the Engineer (or of the Purchaser) being empowered to refuse to inspect any lot of Rails not put in uniform lengths and sorted. 19. The Manufacturer shall supply the material required for testing free of charge and shall, at his own cost, furnish and prepare the necessary test pieces, and supply labor and appliances for such testing as .may be carried out at his premises in accordance with this specification. Fail- ing facilities at his own works for making the prescribed tests the Manufacturer shall bear the cost of carrying out the tests elsewhere. 20. All Rails accepted by the representative of the Engineer (or of the Purchaser) shall be Ac^^ Rails stamped in his presence. STEEL RAILS 37. British Standard Specifications of Flat Bottom Railway Rails (Report No. 11, Revised July, 1909) Issued by The Engineering Standards Committee _ Supported by: The Institution of Civil Engineers; The Institution of Mechanical Engineers; The Institution of Naval Architects; The Iron and Steel Institute; The Institution of Electrical Engineers. (Reprinted by permission of the Committee.) 1. The steel for the Rails shall be of the best quality made by the Bessemer, Siemens- Martin, or other process, as may be approved by the Engineer (or by the Purchaser). The Rails, shall show on analysis that in chemical composition they conform to the following limits: Carbon from 0.35 to 0.50 per cent. Manganese " 0.70 to 1.00 " " Silicon not to exceed 0.10 " " Phosphorus " " " 0.07 " " Sulphur " " " 0.07 " " 2. The Manufacturer shall make and furnish to the representative of the Engineer (or of the Purchaser) carbon and phosphorus determinations of each cast. A complete chemical analysis, representing the average of the other elements contained in the steel, shall be similarly given for each rolling. Such complete analysis shall be made from drillings taken from the Rail or from the tensile test piece or pieces. When the rolling exceeds 200 tons, an additional complete analysis shall be made for each 200 tons or part thereof. Should the Engineer (or the Purchaser) desire to make independent chemical determinations, the necessary specimens and samples shall be furnished by the Manufacturer. For this purpose not more than two Rails in every 100 tons manufactured shall be selected by the representative of the Engineer (or of the Purchaser) and drillings taken with a drill of 2 inches diameter from the top of the head of the Rail unless otherwise specified by him, and if, upon being subjected to the specified tests, either fail to comply therewith, then all the Rails in the cast of which the test pieces form a part may be rejected. The representative of the Engineer (or of the Purchaser) may then take similar samples from a further two rails out of the same 100 tons, and should either fail to comply with the specified analysis the whole 100 tons may be rejected. In case of difference between the Engineer (or between the Purchaser) and the Manufac- turer, as to the accuracy of an analysis, either party shall have the right to have samples of the steel analyzed by an independent metallurgist, to be mutually agreed upon The expenses at- tendant upon such independent analysis shall be borne by the party adjudged to be in the wrong. 3. Each Rail shall be made from an ingot not less than 12 inches square at the smaller end and 14 inches square at the larger end, which must be cogged down into blooms, and have sufficient crop then sheared from each end to ensure soundness. All straightening shall be done by pressure and not by hammering. 4. A rolling margin of | per cent under to \ per cent above the calculated weight will be permitted, but the calculated weight only will be paid for. 6. Before the general manufacture of the Rails is commenced the Manufacturer shall, if required by the Engineer (or by the Purchaser), supply two sets of templates, internal and external, of approved material, for each " B. S." Section of Rail. Each template shall be suitably engraved with the Purchaser's name, the number of the " B. S." section (being the nominal weight of the Rail in pounds per yard), the Manufacturer's name and address, and the date of the Contract. These templates shall be submitted to the Engineer (or to the Purchaser) for his approval, and at the commencement of rolling the Engineer will have a competent person present to approve of the section. RAIL SPECIFICATIONS 5. TABLE OF GENERAL DIMENSIONS AND WEIGHTS OF "B. S.' ; (See Plate XV) Number of "B. S." Sen hin and Nomi- nal Weight per Height of Rail. Width of Head. Calculated Weight of Rail. Yard in Pounds. Inches. Inches. Pounds per Yard. 20 2i 19.96 25 21 1* 24.95 30 3 If 29.98 35 3| 35.03 40 3| 1J 39.98 45 3i lfs 45.10 50 3fg- 2tV 49.94 55 4i 2A 54.78 60 4A 2i 60.11 65 ^ 2t% 64.86 70 4f 2| 69.77 75 4H 2^ 74.79 80 5 2| 79.94 85 5^r 2& 84.87 90 5| 2f 89.92 95 5t% 2H 94.76 100 5f 2| 99.95 General Dimensions and Weights of Rails. 7. Each Section of Rail shall be accurately rolled to its respective template. 8. The whole of the Rails shall be of uniform section throughout, true to templates, per- fectly sound and straight, and free from splits, cracks, burrs, and defects of every kind. 9. A quantity of short lengths will be taken in such lengths and quantities as may be ordered by the Engineer (or by the Purchaser), provided that these short lengths are cut down from longer lengths found to be defective at the ends only, and that the total quantity taken does not exceed 7J per cent of the Contract. 10. The Rails shall be the specified length at a temperature of 60° Fahr. No Rail will be accepted which is more than three-sixteenths of an inch (t s s inch) above or below the length specified, whether for straight or curved lines. 11. When required by the Engineer (or by the Purchaser) Rails are to be supplied from 1 to 6 inches shorter or longer than the normal specified lengths, and these special lengths are to have about one foot at each end painted with such colors as may be ordered. 12. Rails shall be supplied for switches and crossings when so ordered, and such Rails shall be of the required lengths and shall be cut from sound Rails. 13. The Brand (see sketch) shall be rolled on the web of each Rail to show that the Rail is of British Standard Section and made under the conditions of this Specification; the number of the " B. S." Section (being the nominal weight of the Rail in pounds per yard), the process* by which the Rails have been manufactured, the Manufacturer's name, initials, or other recognized mark, and the month and year of manufacture shall also be rolled, in letters three-quarters of an inch (| inch) in size, on one side of the web of each Rail, e.g., W B.S. 95-B.A.* 4.04; and the number of the cast from which it has been rolled shall be stamped on the end of each Rail in half-inch (J inch) block figures. 14. From each cast a piece of Rail (which may be a crop end) shall be selected by the repre- sentative of the Engineer (or of the Purchaser) and stamped with his mark and the number of the cast. From this a piece 5 feet long shall be cut which shall be placed in a horizontal position, with the head uppermost, upon two iron or steel supports resting on a solid foundation, the upper Rails to Conform to Templates. Rails to be Free from Defects. Length of Rails for Straight Line. Permissible Variation in Length. Rails of Special Length for Matching in Curved Line. Rails for Switches and Crossings. Branding. V Impact Test. c The following abbreviations are recommended : ■ S.A. Siemens-Martin Acid. S.B. Siemens-Martin Basic. B.A. B.B. Bessemer Acid. 490 STEEL RAILS surfaces of the supports being curved to a radius of 3 inches. The test shall comprise one blow, delivered midway between the bearings, from a falling iron weight or tup, the striking face of which shall be rounded to a radius of not more than 5 inches. The weight of the tup, the span of the test piece between the centers of the bearings, and the height of the drop for the various sections of Rails shall be as tabulated below. The blow must be sustained without fracture. In addition to the above test the representative of the Engineer (or of the Purchaser) shall select one finished Rail from every 200 offered, and a piece 5 feet in length cut from this Rail shall be similarly tested as specified above. Number of "B. S." Falling Weight Test. Section and Nominal Weight of Rails per Yard in Pounds. Weight of Tup. Centers of Bearings. Drop. Cwts. Feet. .Feet. 20 5 3 8 25 5 3 9 30 10 3 10 35 10 3 12| 40 10 3 15 45 15 3 15 50 15 3 15 55 15 3 m 60 20 3 20 65 20 3 20 70 20 3£ 20 75 20 3| 20 80 20 31 22 85 20 31 24 90 20 3J 26 95 20 3| 28 100 20 3£ 30 Should the length cut from the selected Rail fail to comply with the test specified for its weight, two other Rails from the same cast will be selected and similar lengths cut and tested, and the acceptance or rejection of the cast will be decided by the result of the three tests, so that if two of the Rails selected fail to comply with the test the entire cast will be rejected. 15. From each 100 tons of Rails the Manufacturer shall (if required by the representative of the Engineer or of the Purchaser) cut a test piece from any Rail selected as a sample Rail; such test piece to be stamped to correspond with the sample Rail. It shall then be placed in a testing machine of approved pattern, and shall have an ultimate tensile strength of not less than 40 tons per square inch, nor more than 48 tons per square inch, with an elongation of not less than 15 per cent upon the Standard Test Pieces C or D (see Fig. 341). Should the test piece fail to fulfil these conditions, the representative of the Engineer (or of the Purchaser) may require the Manufacturer to test two other Rails from the same cast in the same manner, and the acceptance or rejection of the cast shall be decided by the result of the three tests, so that if two of the three Rails selected fail to comply with the test the entire cast will be rejected. The representative of the Engineer (or of the Purchaser) may then take similar test pieces from a further two Rails out of the same 100 tons, and should either fail to comply with the test the whole 100 tons may be rejected. Should the Engineer (or the Purchaser) desire to have independent tests made, the Manu- facturer shall provide the necessary test pieces, viz., two for every 200 tons, properly shaped and prepared as described in Fig. 341. 16. The holes for fishbolts shall be drilled through the web from the solid at each end of the Rails, of the sizes and in the position shown in the British Standard Specification for Fish Plates for Flat Bottom Rails (Report No. 47), or on a drawing to be supplied by the Engineer (or by the Purchaser). These holes must be clean and square with the web, without burrs on RAIL SPECIFICATIONS 491 either side, and will be checked with the gauges to be furnished to the Manufacturer by the Engineer (or by the Purchaser). Should any of the holes vary from the correct size or position more than one thirty-second of an inch (s\ inch) the Rails in question will be liable to rejection. 17. The Manufacturer shall give to the Engineer (or to the Purchaser), or his representative, Notice of at least seven clear days' previous notice, in writing, before the rolling of the first lot of Rails, R? llin S to Be and at least three clear days' previous notice, in writing, before the rolling of any subsequent lot of Rails, is commenced, in order that arrangements may be made for the presence of the repre- sentative of the Engineer (or of the Purchaser) at the rolling. 18. The Engineer (or the Purchaser), or his representative, shall have free access to the Inspection and works of the Manufacturer at all reasonable times: he shall be at liberty to examine the Rails Testm £- during any stage of their manufacture, and to reject any material or finished Rail which does not conform to the terms of this Specification. Before the Rails are put before the representative of the Engineer (or of the Purchaser) for inspection, the Manufacturer shall have them examined, and all Rails which he admits to be defective shall be sorted out and placed in a separate stack; the representative of the Engineer (or of the Purchaser) being empowered to refuse to inspect any lot of Rails not put in uniform lengths and sorted. 19. The Manufacturer shall supply the material required for testing free of charge and shall, Testing at his own cost, furnish and prepare the necessary test pieces, and supply labor and appliances Facilities, for such testing as may be carried out on his premises in accordance with this Specification. Failing facilities at his own works for making the prescribed tests, the Manufacturer shall bear the cost of carrying out the tests elsewhere. 20. All Rails accepted by the representative of the Engineer (or of the Purchaser) shall be Marking of stamped in his presence. Accepted Rails 38. Specifications for Street Railway Rails American Society for Testing Materials, Affiliated with the International Association for Testing Materials. — Standard Specifications for Open-hearth Steel Girder and High Tee Rails. Adopted June 1, 1912. I. Manufacture 1. The steel shall be made by the open-hearth process. The entire process of manufac- Process, ture and testing shall accord with the best current practice. 2. Bled ingots, and ingots or blooms which show the effects of injurious treatment, shall Bled Ingots, not be used. 3. A sufficient discard from the top of each ingot shall be made at any stage of the manu- Discard, facture to obtain sound rails. When finished rails show piping, they may be cut to shorter lengths until all evidence of this is removed. II. Chemical Properties and Tests 4. The steel shall conform to either of the following requirements as to chemical composi- Chemical tion, as specified in the order : Composition. Class A. Class B. Carbon, per cent 0.60-0.75 0.70-0.85 Manganese, per cent 0.60-0.90 0.60-0.90 Silicon, per cent not over . 20 not over . 20 Phosphorus, per cent not over 0.04 not over 0.04 5. To determine whether the material conforms to the requirements specified in Section 4, ^ a ^ e an analysis shall be made by the manufacturer from a test ingot taken during the pouring of each melt. Drillings for analysis shall be taken not less than § inch beneath the surface of the test ingot. A copy of this analysis shall be given to the purchaser or his representative. 6. A Check analysis may be made from time to time by the purchaser from a test ingot or Check drillings therefrom furnished by the manufacturer. Analyses. STEEL RAILS Drop Tests. Test Specimens. Number of Tests. Retests. III. Physical Properties and Tests 7. (a) The test specimen shall be tested on a drop-test machine of the type recommended by the American Railway Engineering Association. The specimen shall be placed head upwards on the supports of the machine, and shall not break when tested with one blow in accordance with the following conditions : Weight and Height of Rail. Rails weighing over 100 lb. per yd. and over 7 in. in depth Rails weighing 100 lb. or less per yd., or 7 in. or less in depth. . . . Temperatur ul' Specimen; deg. Fahr. 60-120 60-120 2000 2000 Height of Drop. (b) The atmospheric temperature at the time of testing shall be recorded in the test report. (c) The testing shall proceed concurrently with the operation of the works. 8. (a) Three rails, each from the top of one of three ingots from each melt, shall be selected by the inspector, and a test specimen shall be taken from each of two of these. (b) Drop test specimens shall not be less than 4, nor more than 6 feet in length. 9. Two drop tests shall be made from each melt. 10. If the result of the drop test on only one of the two specimens representing the rails in a melt does not conform to the requirements specified in Section 7, a retest on a specimen from the third rail selected shall be made and this shall govern the acceptance or rejection of the rails from that melt. IV. Standard Sections, Lengths, and Weights 11. (a) The cold templet of the manufacturer shall conform to the specified section as shown in detail on the drawing of the purchaser, and shall at all times be maintained perfect. (6) The section of the rail shall conform as accurately as possible to the templet, and within the following tolerances: (1) The height shall not vary more than ^ inch under nor more than -fa inch over that specified. (2) The over-all width of head and tram shall not vary more than £ inch from that specified. Any variation which would affect the gage line more than jV inch will not be allowed. (3) The width of base shall not vary more than £ inch under that specified for widths less than 6| inches; t\ inch under for a width of 6| inches; and i inch under for a width of 7 inches. (4) Any variation which would affect the fit of the splice bars will not be allowed. (5) The base of the rail shall be at right angles to the web ; and the convexity shall not exceed ¥ z inch. (c) When necessary on account of the type of track construction, and notice to that effect has been given to the manufacturer, special care shall be taken to maintain the proper position of the gage line with respect to the outer edge of the base. 12. (a) Unless otherwise specified, the lengths of rails at a temperature of 60° F. shall be 60 and 62 feet for those sections in which the weight per yard will permit. (b) The lengths shall not vary more than £ inch from those specified. (c) Shorter lengths, varying by even feet down to 40 feet, will be accepted to the extent of 10 per cent by weight of the entire order. RAIL SPECIFICATIONS 493 13. (a) The weight of the rails per yard as specified in the order shall be maintained as Weight. nearly as possible after conforming to the requirements specified in Section 11. (6) The total weight of an order shall not vary more than 0.5 per cent from that specified, (c) Payments shall be based on actual weights. V. Workmanship and Finish 14. (a) Rails on the hot beds shall be protected from water or snow, and shall be carefully Straightening. manipulated to minimize cold straightening. (b) The distance between the rail supports in the cold-straightening presses shall not be less than 42 inches, except as may be necessary near the ends of the rails. The gag shall have rounded corners to avoid injury to the rails. 15. (a) Circular holes for joint bolts, bonds, and tie rods shall be drilled to conform to the Drilling and drawings and dimensions furnished by the purchaser. Punching. (b) In Class A rails the tie-rod holes may be punched. 16. The ends shall be milled square laterally and vertically, but the base may be undercut Milling. sV inch. 17. (a) Rails shall be smooth on the head, straight in line and surface without any twists, Finish. waves, or kinks, particular attention being given to having the ends without kinks or drop. (b) All burrs or flow caused by drilling or sawing shall be carefully removed. (c) Rails shall be free from gag marks and other injurious defects of cold-straightening. VI. Classification of Rails 18. Rails which are free from injurious defects and flaws of all kinds shall be classed as No. 1 No. i Rails. Rails. 19. (a) Rails which are rough on the head or which by reason of surface or other imper- No. 2 Rails. fections are not classed as No. 1 rails, shall be classed as No. 2 rails; providing they do not, in the judgment of the inspector, contain imperfections in such num- ber and of such character as to render them unfit for No. 2 rail uses, and pro- viding they conform to the requirements specified in Section 11. (6) Rails which have flaws in the head exceeding \ inch in depth, or in the base exceed- ing § inch in depth, shall not be classed as No. 2 rails. (c) No. 2 rails will be accepted to the extent of 10 per cent by weight of the entire order. VII. Marking and Loading 20. (a) The name or brand of the manufacturer, the year and month of manufacture, the Marking. letters "O. H.," the weight of the rail, and the section number shall be legibly rolled in raised letters and figures on the web. The melt number shall be legibly stamped on each rail where it will not be covered subsequently by the joint plates. (b) Both ends of all short-length No. 1 rails shall be painted green. Both ends of all No. 2 rails shall be painted white and shall have two heavy center- punch marks on the web at each end at such a distance from the end that they will not be covered subsequently by the joint plates. 21. (a) Rails shall be loaded in the presence of the inspector, and shall be handled in such Loading. a manner as not to bruise the flanges or cause other injuries. (6) Rails of each class shall be placed together in loading. (c) Rails shall be paired as to length before shipment. VIII. Inspection 22. The inspector representing the purchaser shall have free entry, at all times while work Inspection, on the contract of the purchaser is being performed, to all parts of the manufacturer's works 494 STEEL RAILS which concern the manufacture of the material ordered. The manufacturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in accordance with these specifications. All tests and inspection shall be made at the place of manufacture prior to shipment, and shall be so conducted as not to interfere unnecessarily with the operation of the works. 39. Bibliography of Rail Specifications Search furnished by the Secretary of the American Society of Civil Engineers, and made in its Library, January 24, 1910, and January 19, 1912, supplemented by the Technology department of the Carnegie Library of Pittsburgh. 1877 " Permanent-way Rolling Stock and Technical Working of Railways," Vol. 1, p. 512, by Ch. Couche, tr. by James N. Shoolbred. Paris, 1877. Dunod, 49 Quai des Augustins. (Contains specifications for chemical composition of steel rails.) 1879 " The Chemical Composition and Physical Properties of Steel Rails," by C. B. Dudley. Trans. Am. Inst. Min. Engrs., Vol. 7, p. 172 (1879). (Recommends a formula for the chemical composition of rails for the use of the Pennsylvania Railroad.) " Does the Wearing Power of Steel Rails Increase with the Hardness of Steel? " by Charles B. Dudley. Trans. Am. Inst. Min. Engrs , Vol. 7, p. 202 (1879) (four pages). " Discussion of Dr. Charles B. Dudley's Papers on Steel Rails." Trans. Am. Inst. Min. Engrs., Vol. 7, p. 357 (1879) 1880 " The Wearing Capacity of Steel Rails in Relation to their Chemical Composition and Physical Properties," by Charles B. Dudley. Trans. Am. Inst. Min. Engrs., Vol. 8, p. 321 (1880). (Contains references to specifications for chemical composition.) " Specifications for Steel Rails and Track Fastenings." Eng. News, Vol. 20, p. 172 (Sept. 1, 1888). (Specifications drawn up and used by Frank Ward & Bro., of Pittsburg, Pa.) Same. R. R. Gaz., Vol. 20, p. 587 (Sept. 7, 1888). " Steel Rails and Specifications for their Manufacture," by Robert W. Hunt. Trans. Am. Inst. Min. Engrs., Vol. 17, p. 226 (1888). (Contains specifications for Bessemer steel rails.) Abstracts of same. R. R. Gaz., Vol. 20, p. 697 (Oct. 26, 1888); Eng. and Min. Jour., Vol. 46, p. 370 (Nov. 3, 1888). 1893 " Steel Rails: their Manufacture and Service." Eng. News, Vol. 30, p. 172 (Aug. 31, 1893). (Proposed specifications for steel rails.) 1895 " Specifications for Steel Rails of Heavy Sections Manufactured West of the Alleghenies," by Robert W. Hunt. Trans. Am. Inst. Min. Engrs., Vol. 25, p. 653 (1895). (The author states that " the only important features in which the present specifications differ from those of 1888 is in providing for a chemical composition and for drop tests.") 1897 " Brief Note on Rail Specifications," by Robert W. Hunt. Trans. Am. Inst. Min. Engrs., Vol. 27, p. 139 (1897). (One page; report of progress.) RAIL SPECIFICATIONS 495 1899 " Specifications on Structural Steel and Rails," by W. R. Webster. Journal of the Franklin Institute, Vol. 147, p. 1 (Jan., 1899). (General discussion of the subject.) 1900 Proceedings American Railway Engineering and Maintenance of Way Association, Vol. 1, p. 116 (1900). (Refers to specifications for steel rails.) " Recent Practice in Rails: an Informal Discussion." Trans. Am. Socy. of Civ. Engrs., Vol. 44, p. 489 (Paper 887, Dec, 1900). (Gives the standard rail specifications of the Louisville & Nashville R. R. Co., Robert W. Hunt's specifications, and specifications of the Western rail mills, and a review of foreign rail specifications.) " American Standard Specifications and Methods of Testing Iron and Steel," by Albert Ladd Colby. Journal of the Iron and Steel Institute, Vol. 158, p. 215 (1900). (Gives specifi- cations for steel rails.) 1901 " Proposed Standard Specifications for Steel Rails." In Proc. Am. Ry. Eng. and M. of W. Assn., Vol. 2, p. 192 (1901). (Specifications recommended by Committee No. 1 of the Ameri- can Section of the International Association for Testing Materials.) " Nature of Metal for Rails, Report (United States)," by P. H. Dudley. International Railway Congress. Proceedings, Sixth Session, 1900, Vol. 1, Question 1, pp. 205, 248. Brussels, 1901. P. Weissenbruch, 49 Rue du Poincon. (Gives specifications for steel rails.) " Examen des Specifications Normales Americaines Proposees Eprouvettes et Methodes d'Essai du Fer et de l'Acier," by Albert Ladd Colby. In " Communications Presentees devant le Congres International des Methodes d'Essai des Materiaux de Construction tenu a Paris du 9 au 16 Juillet, 1900," Vol. 2, Pt. 1, pp. 147, 162. Paris, 1901. Vve. Ch. Dunod, 49 Quai des Grands-Augustins. (Contains a review of foreign specifications for steel rails and proposed American standard specifications.) " Specifications for Steel Rails," by P. H. Dudley. R. R. Gaz., Vol. 33, p. 158 (March 8, 1901) (one page). " Some Suggestions as to Specifications for Steel Rails," by E. F. Kenney. Eng. News, Vol. 46, p. 226 (Oct. 3, 1901). 1902 American Society for Testing Materials, Proceedings, Vol. 1, pp. 101, 264 (1899-1902). (Proposed standard specifications for steel rails recommended by American Branch of Committee No. 1, American Section of the International Association for Testing Materials. " Review and Text of the American Standard Specifications for Steel, adopted in August, 1901," p. 41, by Albert Ladd Colby. Ed. 2. Easton, Pa., 1902. The Chemical Publishing Co. (Contains specifications for steel rails.) " Proposed Modifications of the Standard Specifications for Steel Rails, Topical Discussion." Proc. Am. Socy. for Testing Materials, Vol. 2, p. 9, 23 (1902). Proceedings of the Am. Ry. Eng. and M. of W. Assn., Vol. 3, p. 201 (1902). (Specifications recommended in 1901 with some amendments.) " Specifications for Steel Rails/' by W. R. Webster, Trans. Am. Inst. Min. Engrs., Vol. 31, pp. 449, 967 (1902). (Contains proposed standard specifications recommended May, 1900, by the American Branch of Committee No. 1 of the International Association for Testing Materials.) " Steel Rails: Specifications," by Robert Job. Am. Eng. and R. R. Jour., Vol. 76, p. 310 (Oct., 1902). (Gives specifications of the Philadelphia & Reading Railway Company for steel rails.) 1903 " The Present Situation as to Specifications for Steel Rails," by William R. Webster. Trans. Am. Inst. Min. Engrs., Vol. 33, p. 164 (1903) (five pages). 496 STEEL RAILS "Proposed Modifications in the Specifications for Steel Rails adopted by the American Railway Engineering and Maintenance of Way Association in March, 1903." Proc. Am. Socy. for Testing Materials, Vol. 3, p. 74 (1903). 1904 " British Standard Specification and Sections of Bullheaded Railway Rails." Engineering Standards Committee. Report No. 9. Lond., 1904. (10s. 6d. net.) " Specifications for Steel Rails of the American Railway Engineering and Maintenance of Way Association, as Amended and Adopted in March, 1904," with Introduction by William R. Webster. Proc. Am. Socy. for Testing Materials, Vol. 4, p. 195 (1904). (Showing main difference in specifications adopted by the two societies.) " Standard Specifications for Bessemer Steel Rails." In Proc. Am. Ry. Eng. and M. of W. Assn., Vol. 5, p. 465 (1904). " Specifications for Bessemer Steel Rails." Eng. News, Vol. 50, p. 275 (March 24, 1904). (Gives specifications adopted by the American Railway Engineering and Maintenance of Way Association.) 1905 " Railroad Construction," p. 243; by Walter Loring Webb, M. Am. Socy. C. E. Ed. 3. N. Y., 1905, John Wiley & Sons, 43 E. 19th St. (Contains proposed standard specifications for steel rails of the American Railway Engineering and Maintenance of Way Association, March, 1902.) British Standard Specification and Sections of Flat-bottomed Railway Rails. Engineering Standards Committee. Report No. 11. Lond., 1905. Leslie S. Robertson, Secy., 28 Victoria Street, Westminster, S. W. (10s. 6d. net.) " Steel Rails," by William R. Webster. R. R. Gaz., Vol. 38, p. 440 (May 5, 1905). (Gives specifications of the American Railway Engineering and Maintenance of Way Association.) 1906 " On Specifications for Steel Rails." Proc. Am. Socy. for Testing Materials, Vol. 6, p. 35 (1906). (Gives proposed standard specifications for steel rails.) Proc. Am. Ry. Eng. and M. of W. Assn. Vol. 7, p. 553 (1906). (Gives comparison of specifications of American Railway Engineering and Maintenance of Way Association and the American Society of Civil Engineers.) " Rails for Lines with Fast Trains." Reports; by P. H. Dudley and Van Bogaert. Inter- national Railway Congress, Seventh Session, 1905, Vol. 1, Question 2, pp. 141, 194. Brussels, 1906. P. Weissenbruch. (Contains very brief data on rails specifications.) " Specifications for Steel Rails." R. R. Gaz., Vol. 40, p. 280 (March 16, 1906). (Specifi- cations recommended by the American Railway Engineering and Maintenance of Way Association, American Society for Testing Materials, and American Society of Civil Engineers.) 1907 " Report of the Special Committee on Rail Sections to the American Society of Civil En- gineers." Proc. Am. Socy. of Civ. Engrs., Vol. 32, p. 52; Vol. 33, p. 290 (1906, 1907). (Contains recommended specifications for Bessemer steel rails.) " Manual of Recommended Practice for Railway Engineering and Maintenance of Way," p. 55. Am. Ry. Eng. and M. of W. Assn. Edition of 1907. (Contains specifications for rails.) " Proposed Standard Specifications for Steel Rails." Proc. Am. Socy. for Testing Materials, Vol. 7, p. 40 (1907). (Specifications adopted Sept. 1, 1907.) " The Steel-rail Discussion, American Society for Testing Materials." Ry. and Eng. Review, Vol. 47, p. 570 (June 29, 1907). " Proceedings of the Session of the American Railway Association, October 30, 1907," p. 175, N. Y., 1907. (Report of the Committee on Rail Sections giving specifications for Bessemer steel rails with explanatory notes.) RAIL SPECIFICATIONS 497 " Standard Specifications for Steel Rails." Proc. Am. Soc. for Testing Materials, Vol. 7, p. 44 (1907). Same. Eng. Record, Vol. 55, p. 774 (June 29, 1907). Comparison of American and Foreign Rail Specifications, with a Proposed Standard Speci- fication to Cover American Rails for Export," by Albert Ladd Colby. Trans. Am. Inst. Min. Engrs., Vol. 37, p. 576 (1907). (Contains bibliography.) Same. Iron and Coal Trades Review, Vol. 73, p. 357 (July 27, 1906). " Rail Sections and Specifications." R. R. Gaz., Vol. 43, p. 250 (Sept. 6, 1907). (Com- pares rail specifications of the American Society of Civil Engineers, American Railway Engineering and Maintenance of Way Association, American Society for Testing Materials.) " Some Progress Toward Getting Better Rails." (Editorial.) R. R. Gaz., Vol. 43, p. 577 (Nov. 15, 1907). (Brief discussion of rail specifications.) " Proposed Standard Rail Sections of the American Railway Association." R. R. Gaz., Vol. 43, p. 627 (Nov. 22, 1907) (illustrated). " Rail Specifications." R. R. Gaz., Vol. 43, p. 735 (Dec. 20, 1907). (Contains specifica- tions of the American Railway Association.) 1908 " Railway Track and Track Work," p. 78; by E. E. Russell Tratman, Assoc. M. Am. Socy. C. E. Ed. 3. N. Y., 1908. Engineering News Publishing Co., 220 Broadway. $3.50 net. (Contains a comparative table of specifications for chemical composition of rails.) Proceedings of the American Railway Association, Special Session, February 7, 1908; Regular Session, April 22, 1908, p. 359, N. Y., 1908. (Specifications for Bessemer and open- hearth steel rails, accompanying the Report of the Committee on Standard Rail and Wheel Sec- tions, dated March 23, 1908.) " Standard Specifications for Steel Rails." Proc. Am. Soc. for Testing Materials, Vol. 8, p. 44 (1908). (Specifications adopted Aug. 15, 1908.) " The Present Status of Rail Specifications." R. R. Age, Vol. 45, p. 76 (Jan. 17, 1908). (A review of the action taken by the American Railway Association.) American Society of Civil Engineers, Report of Special Committee on Rail Sections. Eng. News, Vol. 59, p. 105 (Jan. 23, 1908). (Recommended specifications for Bessemer steel rails.) " New Steel-rail Specifications of the Pennsylvania Railroad." Eng. News, Vol. 59, p. 426 (April 16, 1908). (Gives specifications for chemical composition, process of manufacture, mechani- cal requirements, tests, and inspection.) " The Pennsylvania New Rail Sections and Specifications." R. R. Gaz., Vol. 44, p. 539 (April 17, 1908). " New Rail Sections and Rail Specifications of the American Railway Association." Eng. News, Vol. 59, p. 530 (May 14, 1908). (Specifications for Bessemer and open-hearth steel rails.) "American Railway Association's Rail Committee." (Editorial.) Eng. News, Vol. 59, p. 533 (May 14, 1908). (Comments on the rail specifications; one and a half columns.) " Steel-rail Breakages; Questions of Design and Specifications," by Harold V. Coes. En- gineering Magazine, Vol. 35, p. 417 (June, 1908). (Gives specifications for the Union and Southern Pacific railways and British standard chemical specifications for steel rails.) " Some Features of the Present Steel Rail Question," by Charles B. Dudley, Proc. Am. Soc. for Testing Materials, Vol. 8, p. 19 (1908). (Discusses changed demands on steel rails and pro- posed specifications.) Same. Engineering News, Vol. 60, p. 9. 1909 " Proceedings of the Session of the American Railway Association held in Chicago, Novem- ber 17, 1909," p. 995. N. Y., 1909. W. F. Allen, Secy., 24 Park Place. (American Railway Association specifications for Bessemer and for open-hearth steel rails, adopted as recommended practice April 22, 1908.) 498 STEEL RAILS Proceedings Am. Ry. Eng. and M. of W. Assn., Vol. 10, Pt. 1, pp. 369, 374 (1909). (Recom- mended changes in specifications as previously adopted by the Association.) " New Rail Section and Specifications, Canadian Pacific Ry." Ry. and Eng. Review, Vol. 49, p. 27 (Jan. 9, 1909). (Gives specifications for open-hearth and Bessemer rails.) " New Rails for the Canadian Pacific Ry." (Editorial.) Ry. and Eng. Review, Vol. 49, p. 34 (Jan. 9, 1909). (Discusses specifications and rail sections.) " New Rail Specifications of the Pennsylvania R. R. System." Eng News, Vol. 61, p. 50 (Jan. 14, 1909). (Revision of specifications of Feb. 4, 1908.) " Pennsylvania Rail Specifications." R. R. Age Gaz., Vol. 46, p. 101 (Jan. 15, 1909). (Specifications of the Pennsylvania Railroad evised under date of Dec. 10 1908.) " The New 85-pound Rail Section of the Canadian Pacific Ry." Eng. News, Vol. 61, p. 272 (March 11, 1909) (illustrated). " Recent Developments in Rail Design and a Comparison of Rail Sections." (Editorial.) Eng. News, Vol. 61, p. 276 (March 11, 1909). (Compares rail specifications.) " Recent Rail Sections." R. R. A e Gaz., Vol. 46, p. 537 (March 19, 1909) (one page, illustrated). " New Rail Orders and Specifications." (Editorial.) R. R. Age Gaz., Vol. 46, p. 535 (March 19, 1909). (Discusses rail specifications of various railroads.) " Rail Specifications." (Editorial.) R. R. Age Gaz., Vol. 46, p. 925 (April 30, 1909). (Very brief.) " Rail Specifications " (letter), by R. Trimble. R. R. Age Gaz., Vol. 46, p. 1018 (May 14, 1909). (Brief letter correcting error in the above editorial.) " Comparative Rail Specifications." R. R. Age Gaz., Vol. 46, p. 1066 (May 21, 1909). (Compares specifications of the American Railway Association, Steel Manufacturers of America, American Society of Civil Engineers, American Railway Engineering and Maintenance of Way Association, and American Society for Testing Materials, with comments.) " Rail Sections and Specifications." (Editorial.) R. R. Age Gaz., Vol. 46, p. 1060 (May 21, 1909). " Specifications for 90-pound Bessemer and Open-hearth Steel Rails for the Harriman Lines." R. R. Age Gaz., Vol. 47, p. 185 (July 30, 1909). (Specifications to which the Harriman Lines are ordering their 1909 rails. " On the Question of Strengthening the Track and the Bridges with a View to Increasing the Speed of Trains Subject II, for Discussion at the Eighth Session of the Railway Congress," by M. L. Byers. Bulletin of the International Railway Congress Association, Vol. 23, p. 908 (Sept., 1909). (Gives rail specifications proposed by he American Railway Association and by the Pennsylvania Railroad Committee.) " Report of Committee on Rail, American Railway Engineering and Maintenance of Way Association. Bulletin 118 (Dec, 1909). (Specifications for steel rails and review of previous reports.) Abstract of same. " Specifications for Steel Rails." Railway and Engineering Review, Vol. 50, p. 118 (Feb. 5, 1910). " Standard Specifications for Bessemer Steel Rails." Proceedings American Society for Testing Materials, Vol. 9, p. 62 (1909). (Adopted Aug. 16, 1909.) " Standard Specifications for Open-hearth Steel Rails." Proceedings American Society for Testing Materials, Vol. 9, p. 66 (1909). (Adopted Aug. 16, 1909.) " La Voie Courante des Chemins de Fer de l'Etat Beige," by Pierre Decamps. Revue Gen- eral des Chemins de Fer et des Tramways, Vol. 32, Pt. 2, p. 267 (Oct., 1909). (Appendix gives rail specifications of the state railroad of Belgium.) " Revised Rail Specifications, Pennsylvania Railroad System." Engineering, Vol. 87, p. 218. British Standard Sections, No. 47. Engineering Standards Committee (1909). (British standard specifications for bull headed and flat bottom railway rails.) RAIL SPECIFICATIONS 499 " Specifications for Standard Open Hearth Steel Rails for A. S. C. E. Sections," Carnegie Steel Co., Jan. 1, 1909. (Two leaflets.) " Specifications for Standard Bessemer Steel Rails for A. S. C. E. Sections," Carnegie Steel Co., Jan. 1, 1909. (Two leaflets.) " Specifications for Steel Rails." Baltimore and Ohio R. R. Co., No. 163C, Jan. 25, 1909. (Two leaflets.) " Specifications for Open Hearth Steel Rails." Proceedings American Street and Inter- urban Railway Engineering Association, Vol. 7, p. 59 (1909). (Includes specifications adopted by the Transit Supply Co., Lorain Steel Co., Pennsylvania Steel Co., and the Manganese Steel Rail Co.) 1910 " Permanent Way." R. R. Engr., Vol. 31, p. 18 (Jan., 1910). (Gives Pennsylvania Railroad System specifications for steel rails.) " Final Report of Special Committee on Rail Sections." Transactions American Society of Civil Engineers, Vol. 70, p. 456 (Paper 1177, Dec, 1910). (Contains reprint of rail specifica- tions of the American Railway Engineering Association.) " The American Railway Association, The American Railway Engineering and Maintenance of Way Association, Specifications for Steel Rails." Proceedings American Railway Engineering and Maintenance of Way Association, Vol. 11, Pt. 1, p. 254 (1910). Abstracts of same. "Specifications for Steel Rails." Railway and Engineering Review, Vol. 50, p. 118 (Feb. 5, 1910). "Rail Specifications and Sections," Engineering News, Vol. 63, p. 384 (Mar. 31, 1910). " Track Standards and General Rules." Department of Maint. of Way, Metropolitan Street Railway Co. Elec. Ry. Journal, Vol. 35, p. 863. " Recent Work of the German Street and Interurban Railway Association." Elec. Ry. Journal, Vol. 35, p. 38. (Considers specifications and standards agreed upon.) Hunt (Robert W.) & Co., Engineers. Bureau of Inspection, Tests and Consultation. (Includes "Specifications for Standard Open-hearth Steel Girder and High Tee-Rails," 1910, American Street and Interurban Railway Engineering Association, p. 5; and "Specifications for Standard Open-hearth Steel Girder and High Tee-Rails," Lorain Steel Co., Jan. 1, 1910, p. 14.) 1911 " Standard Specifications for Bessemer and Open-hearth Steel Rails." March 21, 1910, United States Steel Products Export Co. (Year-book, American Society for Testing Materials, 1911, p. 202.) " Rail Sections and Specifications." Elec. Ry. Journal, Vol. 37, p. 8. (Editorial, dis- cussing progress toward uniform specifications in 1910.) " Interborough Rails for Tangents and Curves." Elec. Ry. Journal, Vol. 37, p. 82. (Gives recent modifications of specifications of open-hearth steel rails.) Same, abstract, Journal of the Iron and Steel Inst., Vol. 84, p. 619. " Manufacturers' Standard Specifications for Bessemer Steel Rails," Association of American Steel Manufacturers. Year-book, American Society of Testing Materials, 1911, p. 199. " Specifications for Basic Open-hearth Rails," New York Central Lines. (Specifications of Oct. 1, 1909, revised Jan. 11, 1911, to conform to manufacturers' sale per 100 pounds.) " Specifications." Report of Committee on Rail. Proceedings American Railway En- gineering and Maintenance of Way Association, Vol. 12 (1911), Pt. 2, p. 12. (Gives short report of progress.) Report of Committee A-l. Proceedings American Society for Testing Materials (1911), Vol. XI, p. 48. (Contains reference to international specifications for rails.) 500 STEEL RAILS 1912 " Specifications for Carbon Steel Rails." Proceedings American Railway Engineering As- sociation (1912), Vol. 13, p. 565. " New Specifications for Steel Rails." Iron Age, Vol. 89, p. 816. (Gives report of rail com- mittee at 1912 meeting of the American Railway Engineering Association and specifications adopted.) " Specifications for 85-pound and 100-pound Carbon Steel Rails," 1912, Pennsylvania Rail- road Company. (Two leaflets.) " Specifications for Standard Bessemer Steel Tee Rails," 1912 Catalogue, Maryland Steel Company, p. 10. " Specifications for Standard Open-hearth Steel Tee Rails," 1912 Catalogue, Maryland Steel Company, p. 12. " Specifications for Standard Open-hearth Steel Girders and High Tee Rails," 1912 Cata- logue, Pennsylvania Steel Company, p. 14. APPENDIX REPORTS AND RECORDS The forms recommended by the Rail Committee of the American Railway Engineering Association, and contained in the 1911 Manual of the Association, are typical of the best practice, and are shown on Figs. 342 to 359 inclusive and Plate XXXIII. The explanation of the forms as given by the committee is as follows: Group I. Reports of Rail Inspection and Shipment at the Mill This set of forms, Figs. 342-344 and Plate XXXIII, is for the use of the railroad company's Inspector at the mills where the rail is rolled, and gives all the information necessary to inform the purchaser that his order has been manufactured in accordance with the specifications and shipped. A. B. & C. R. R. Report of Chemical and Examination Co. Physica ' 1 Sheet No. lof Shells' For _ Order No. of No. _ Shrinkage A lowance at Saws inches on 33-ft. rails Weight of Tup, 2000 lbs. Height of Dr Average Number of Rails per Heat Heat No. P ™ g ln g ot CrOP t I 1 | J §■11 _. Egote Top e'ciZ ! 2 3 4 5 6 7 8 9 10 For lling in vith ty ewriter column si d b, ? m cd in te ths < ., ,|,..|, ? nres 11 7 4 5 5 5 S 5 5 5 5 5 ■5 II 12 sheet i qmred SxlOj i chcs. 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Note — Requirements of Standard Specifications are to be sta Instructions One copy of this report to be forwarded to Correct the Chief Engineer M of W Approved ■ ted on line 1 Inspector \^TZ t , Fig. 342. M. W. 401. — Report of Chemical and Physical Examination: This blank is filled out from the mill records under the supervision of the Inspector, and gives the chemical contents taken from the ladle analysis and the result of the drop test. (503) A. B. & C. R. R. Co. No._ Certificate: of- inspection of Process Rails lbs. per yd Section. Manufactured by Steel Co. at Works For Mr Chief Engineer M. of W. Date_. The following Steel Rails have been inspected and accepted accordir s are certified to be within the limits of the Specifications of the ._19-. and approved as per details given below. All Rails have been inspected and approved for Chemical Analysis, Physical Tests, Section, Weight, Straightening. Drilling, Sawing, Length, Stamping, Finish, Quality. All Rails are marked on the web with maker's name, date of manufacture. Heat Number, and position occupied in the ingot. Date of Rolling No. of Rails Rolled No. of Rails Accepted No. of Rails temporarily rejected and cause , -x&-4 *i*t*M K £ji ra EvaI M e if known. (See "Description of Failur Approved: . . Foreman and Description of Failur M. W. 404. Fig. 345. (Face of Form.) - Report of Rail Failures in Main Tracks: This is the basic report of all rail failures and is sent by the Track Foreman to his Supervisor and by him transmitted to the Division Engineer. It contains a classification of rail failures which is used in the tabulations employed in the following blanks. INSTRUCTIONS The Foreman will send this Report discovered, and in the case of a out of the track. The Supervisor will forward this Report direct to the Division Engineer. The Division Engineer will have copies of this Report made immediately upon receipt and send a copy to the Chief Engineer M. of W. The answer to 3 is in raised characters on the web of the rail. The answer to 4 is "Bessemer" (B) ; "Open-Hearth" (O.H.) ; "Nickel" (N.) ; "Ferro-titanium (F.T.) ; "Chrome Nickel" (CN.) ; or other method of manu- facture or alloy. The answers to 5 and 6 are stamped into the metal on side of web — figures for 5 and a letter for 6. f South G. Mile Post No. fro IE ■nd of Div DESCRIPTION OF RAIL FAILURES When describing Failures of Rails, the following terms should be used. Flow or Metal. This term means a "Rolling Out" of the metal o: of the head towards its sides without there being any indication of a I ing down of the head structure, that is, the under side of the head i distorted. Crushed Head. This mpanied by a crushin e >■ 2 ± Fig. 345 (continued). (Back of Form.) 'ON 3"!1 H « „ - W . - 0= 0. o H 2 a s 2 2 S a 2 :. 1 I § aoil<3S P in a 3Di[ds ai s \ usj[oja a qsM IHflS g pe»H WS s P E3 H p 3 qsiu 3 a [EjaW JO *0[j a ira^jg g P33EUIEQ a II 1 s I ! i 1 a 1 ! J. = 1 a s " ll'ojli piracy i|»no K JO Xeq a I! jco A s 1 s a . OS 05 1 as |°l » Jo 3Ajno 3 2 l 1 a 1 a 1 a sqiSuaq s U P. ■wiiaT . l - ll - ill • * | 1 „ S * |°J » P-">A JSd jqSiaAi - 1| - B B: ; | M. W. 405. — Superintendent's Monthly Report of Rail Failures in Main Tracks : On this blank the Division Engineer informs his Superintendent of the total number of rail failures for the month, tabulated from the Track Foreman's (508) INSTRUCTIONS A. The Division Engineer will make out two copies of this report at the end of the month from the Section Foremen's Reports, and send one copy to the Chief Engineer M. of W. and one to the General Superintendent. DESCRIPTION OF RAIL FAILURES When describing Failures of Rails, the following terms should be used: iROKEN Rail. This term is to be break will come under this head. C 2. Flow of Metal. This t< of the head toward, its, ing down of the head s distorted. eans a "Rolling Out" of the metal on top .vithout there being any indication of a break- re, that is, the under side of the head is not Split Head. This term includes rails split through or near the of the head, or rails with pieces split off the side of the head, term is used it should be further defined by stating whether it accompanied by a seam or hollow head. 2 A EZf Fig. 346 (continued). (Back of Form.) report, and other officers who are interested, such as the Chief Engineer, Chief Engineer of Maintenance of Way, or General Superintendent, are furnished with copies. In cases where a copy of the Track Foreman's report is sent to the Chief Engineer or Chief Engineer of Maintenance of Way, the monthly report serves as a check on the receipt of all individual rail reports. (509) A. B. & C. R. R. Co. Division. Main Track. December 31, 19 _ . Location . j «. * 1 | Length of Feet in Tra:k From To Laid Previous to 19 New Steel Laid 19 Steel Laid 19 Remarks. M.P. + ft. M.P + ft. I 3 4 4 5 4 5 3 12 4 5 8 7 7 16 heet required 8 inches No. ft. 601 " " 70 " " 85 " " 100 Column 3 to be used for any special rail, s and Re-drilled. To be made out and forwarded by the Eng Engineer M. of W., as soon after the close of t b.Rail No. Tons ich as Re-rolled or Sawed Correct: neer M.of W. to the Chief le year as possible. Engineer M.ol W. Fig. 347. M. W. 406. — Annual Statement of Steel Rails Existing in Main Tracks: This is an annual report sent by the Division Engineer to the Chief Engineer or Chief Engineer of Maintenance of Way, for the permanent record of the com- pany, to show the different kinds of steel in the main tracks at the end of the year. This may be used in conjunction with the rail chart, or take its place altogether, because the rail chart may not be in convenient form for a per- manent record, which may be referred to, after many years, for information concerning the kind of rail in use at a stated period. (510) * .2 2D 1 2 C 1 i 1 3 ■g.2 1j (511) Group III. Laboratory Examination of Special Rails This group is, at present, represented by the single form shown in Fig. 348. It is used for making check analyses against the mill analyses and for reporting the result of chemical analysis and physical test of special rail or other test pieces which may be sent to the laboratory, from time to time, for examination. Fig. 349 shows standard locations of borings for chemical analyses and also the standard tensile test pieces of the association. FOR CHEMICAL ANALYSES. To be of maximum IF RAIL IS FLANGE WORN, THE BORINGS AND TEST PIECE FROM THE UPPER PART OF HEAD SHALL BE TAKEN FROM THE OPPOSITE CORNER. FlHfl— ''i — W- - Standard Locations of Borings for Chemical Analyses and Standard Tensile Test Pieces. Group IV. Compilation of Results for Study This group, Figs. 350-354, exhibits the different ways for compiling quan- titative statistics of rail failures. M. W. 408 (Fig. 350) is intended for compiling the information relative to rail failures for a period of one year. The columns for "specified chemical analysis " are intended for recording the analysis of the particular lot of rail as given in the specification, and is inserted in this blank in order to give an idea as to whether the rail is high or low in carbon, or high or low in phosphorus, etc. M. W. 409 (Fig. 351) has been provided on which the results from M. W. 408 will be recorded at the end of the year, thus making a continuous record. (512) s, g i '> i |asi Jfgj lis"? Ill ...n - « n » „ ■ - CO ■ 2 ; 2 2 » 2 2 £ 2 2 g - 31 s| 1 J ' j r 1 I r { = I | 1 1 | = f ! J - i 1 ! «. i « i ^ z u 1 « 1 ct 1 ..'- 1 « i K ° aqj dn'jooj ■ 'uoipss '}q2i3A\ aqj saiS pire 'pjpq rim lasqs aq; ss jiei |0 spupj A"tmu St ]33qs qoea uo Jajir^ ■ •aNvia sihx ni ONrnid hoj SNOixoauia 33UH - » - . * • - CO a 2 a a 2 -3 2 2 a a.a P'H ^ | O H ^ 1 s 1 3 | * 5 I T> I £ * o I ! j 1 - £ ,£ " 3 * a « 5 s 3 ^ 3 § « 1 I - 5 1 : | , 5 3 - £ 3) 1 "6 * 1 j , \ >i ° s , E s E " J j , 1 (0 1 . i 1 j , 7 ! 7 z z ? ? ? ? z 7 7 ? ' 7 I 7 ? ? J ? f ? z 7 7 ? ? 7 z ? ? 7p*** * b - ; 1 I L 'l '- i ! 2 I - ; - * 1 '1 *| *| 65 | *| *| «| - . s i , i * 1 1 , 3 , t' ' 1 -0 1 1 •2 I , s t | 3 , ° 1 9 1 ~ „ E i , a : - -, J Hi ^ 8-5 , 1 ssan - c, ™ * '° ° '- GO o, 2 2 2 2 2 a a^l a 1 c j l||I *> Sheet No of Different Section or Patte npanies. 6h - B * £ - jjj 1 1 1 B B 1 1 . 1 s 1 * 1 - ! I \ - 1 ■i - 1 ■ * j (5 o | L. I 3 * 1 : - 1 J I * £ s L (0 a E § r , , , . - $ Z « £ - UJ3MEJ JO - ■sqi 'pjEX J3d , s Fig. 352. M. W. 410. — Comparative Number of Failures of Steel Rails of Different Section or Pattern, Rolled by Different Steel Companies: In order to compare the product of different mills, and also to compare different weights per yard and different sections together, this blank has been provided. It contains the totals taken from M. W. 408 or M. W. 409 as desired. (515) r a ^ £ t -, •o <" "H 1 °"E £2-3 ill "3 -3 & 1 §s§ sag 1 11 g 8 s - %-°L 2 2 i! \ 3 . 2 JU h v H » Q > o u , PQ > § , < u > S A I 1 i ■n if fa .> fa § 1 I s * I 1 Q * 1 o v - a* a* • c (2 I** fa : 73 < 1 , i a * 1 ■3 w, = "" fc v "H fa >. b K cH .2 «- Q 5 O g fa - < 1 f „ -' 1 A 1 ! | Q. s| ' - PK "" H - ; * Q - " * pq : " < v o S 2 £ , s •s i s S - £ , | = ! b \ I 1 ■ : i = is : H Fig. 353. M. W. 411. — Position in Ingot of Steel Rails which Failed: This is intended to furnish data on the number and character of rail failures according to the original position in the ingot held by the rail in question. (516) (Cover Page for Forms M. W. 408, 409, 410. 411.) A. B. & C. R. R. Co. Numerical Record and Position in the Ingot of Steel Rails which have Failed in Service. M.W.412: The information in this group should be bound together in one book; this cover has been provided for convenience and neatness. Group V. Progressive Wear of Special Rail under Observation In order to keep track of special rail, from time to time, and determine the value of the results being given, it is necessary to have a systematic plan of procedure for examinations and records. This group, Figs. 355-359, is fur- nished for that purpose, and is provided with a cover, as in the case of the previous group. (517) 1 Division Rails R. F red in 19 id Location D of Laid in 19 Remo Between a Office of Chief Engineer M. of Scale 1 in.=l mile Date >< i t 6 | I < « < » < « < « < » < « < 1 I Total sq. in. abraded Ave. sq. in. abraded Percentage of Area abraded to total Area of Head M. W. 413. — Location Diagram: This blank is on a scale one inch equals one mile, and is intended for dia- grams showing the location in different places of the same kind of rail under trial. (518) ! ; 5 ft! ft! U 3, Total sq. in. abraded Ave. sq. in. abradec Percentage of Area abraded to total Area of Head Fig. 356. M. W. 414. — Location Diagram: This is similar to M. W. 413 except that it is on a scale of two inches equal one mile, and is intended to show the location of a particular portion of the rail given in M. W. 413. It is made on a larger scale, so as to locate the points of measurement. A place is provided on each blank for the summary of the wear or area abraded in percentage of total area of head. (519) Fig. 357. M. W. 415. — Diagram Showing Lines of Wear: The measurement of rail section at a specified point is shown on this blank and its position on M. W. 414 is given by the number in the circle of the blank at the top. All statistical information of interest and importance is given on the blank. (520) A. B. & C. R. R. Co. Division Record of Comparative Wear of Special Rail Date of Report 19 i B c < en < | = ^ 1 1 I ■g I I 1 o 2 11 - 8 = ^ #1 "» uoday jo ajsp je aoiAjag jo qjguaq ; 10 P3A01U3-JJ 3JEQ ; piCT 3JEQ * Chemical Composition of Rail of Section with which Special Rail was Compared s «. 9 > » * c^ J! - , 1 1 m 0. : - u T <• ; l ! i i s- - ^ * - ■a ■ : - B5 * ; 1 " ~ : " u - JSJMDEjnUBIM £ s uonosg jo sdit of 1 pair ■TIUlWii -311b. ' 1 l | f lie joint chairs are 91 ins. wide, and mil* 54 @ te chairs are 71 ins. wide, and weigh 46 60 lbs. per yd. \. S." Section No. 60. 80 lbs. per yd. "B. S." Section No. 80. Plate XIV. —British Standard Bull Head Railway Rails. Pi^te XV. — British Standard Flat Bottom Railway Rails. Tram Girder Rails, Pennsylvania Steel Company. 85 lbs. per yd. 100 lbs. per yd. lbs. per yd. Standard High Tee Rails of the American Electric Railway Engineering Association. Plate X\I. — Rail Sections for Street Railways, Tram Girder Rails and High Tee Rails. 7-in. Groove Rail, 106 lbs. per yd. 9-in. Groove Rail, 120 lbs. per yd. 7-in. Guard Rail, 122 lbs. per yd. 9-in. Guard Rail, 141 lbs. per yd. View showing amount that may be worn from head of Groove Rail before standard wheel flange will come in contact with lip of rail. Plate XVII. — Rail Sections for Street Railways: Standard Girder Sec- tions of the American Electric Railway Engineering Association. For use in paved streets with heavy vehicular traffic. 24-25J Plate XVIII. — British Standard Tramway Rails. Crossing Frogs in Poor DATUM LINE DATUM LINE Applir.ilioii of Brakes, Straight, Level Track. DATUM I JNE = — DATUM LINE 24 30 [Plate XIX. — Deflection of Drh 15 18 21 TIME IN SECONDS Note. — Static Load Deflection 0.5 in. below Datum Line 'heel Spring, Consolidation Engine No. 1064, Boston and Maine Railroad. (Coes and Howard.) 2TT- Atlantic Type Passenger Locomotive. hooded Weights. On leading truck 42,500 pounds On driving wheels 105,000 pounds < )n liiiilni!- I ruck 42,500 pounds Tot ;il engine 190,000 pounds Tender 130,000 pounds Prairie Type Locomotive Loaded Weights. On leading truck On driving wheels 1 10 pounds K) pounds Pacific Type Passenger Locomotive. Loaded Weights. On leading truck 36,900 pounds On driving wheels 147,800 pounds On trailing truck 40,300 pounds Tola! engine 225,000 pounds Tender 162,800 pounds Plate XX. — Pass can Locomotive Co.) Loaded Weights. On driving wheels 445,000 pounds Mogul Type Freight Locomotive. Loaded Weights. On driving wheels 1511.000 pounds On leading truck 28,000 pounds Total engine 187,000 pounds Tender 140,000 pounds Plate XXI. — Freight Locomotive Diagrams. (From dii "V" f DIP """V b^ p LJ p ,, r - T: n n n n __, , _is^, 07 Di n n p 3 fl] = MoKee Single-flange Plate. Plate XXII. — Examples of American Tie Plates. Pittsburgh and Lake Erie Railroad Tie Plate. V :_ __ Plate XXIII. — Rail Diagram of Love. 0.46 original size. Note.— In the curve of bending moments, the maximum bending moments under the wheels arc determined by rombmin:: ihc nonnil moment i.lia^nmis, -luiw-n in dotted hnes, with the moments a the adjacent ties. Plate XXIV.— Examples of American Rail Joi /OO /25 /SO Axle Spacing' Inches 175 ZOO 50 1^50 ^^ v Plate XXVI.-Dynamic Wheel Loads for Various Rails and Axle Spacing. — £^to ^-^ ^-- --- — ^JS^ I I I I I I . n ? S c /0 ° , , ^ 5 50 75 r 100 /25 ftxle Spacing Inches /jx/e Spacing Inches Class B Track. Class C Track. 500.000 J =50 T=4-o 1=30 A /^' I=ZO__ f /^30 ^^ ^ I*ZO BENDING MOMENTS IN DIFFERENT RAILS WHICH WILL CAUSE AN EXTREME FIBER .STRESS OF 20,000 LBS. PEE SQ. IN. IN THE BASE OF THE 75 100 125 /50 Axle 5pacmg Inches /75 ZOO 50 it Weights of Rail Corresj 75 100 Its Axle Spacing Inches ■ "SZZSSS? *s$£ixsr- 40 35 8 1S.0 13.5 27C 24C 000 000 000 000 000 I' 50 /-- 40 I* 30 /= Zo 50 a 7 , 5 c w0 , '25 Mxie j pacing inches v<» eg 80 ft. 4 n E 30,000 40,000 50,000 Static Axle load lbs. <3L la 1 h % A i 1 // i A 1 /I t /( 30,000 40,000 50,000 6QOO0 Static Axle load Ib5. ^3 01 -ffi. ..JOS:^ mi SL i, I OonsolulMion Lncomotive-". ^P^P^T i V i p f rf / i i / / 1 i // ' // 1 1 // 20,000 30,000 40,000 50,000 •Static Axle load lbs. Era. B.— Ten Wheel Loci CD QCDojn ^ ^ ^70 7 4 V 1 / // k\ // 1 i '/ i 1 / / £Q0O0 JQGO0 4Q000 Static Axle load Ib5. Era. D. — Freight Cars and Six Wheel Passenger Cars F CD CO ^q P CD CD CO i Steam Roads. h/00 Class A Track. - Class 13 Track. - Class C Track. - — rf— Zi >£ ^Q000 JQOOO 40,000 Static Axle load lbs. 9 o on Electric Roads. Plate XXLX. — Plan of Gary Steel Plant. (Harbord and Hall.) Plate XXX. — Reversing Cogging Mill. (Harbord and Hi Platk XXXI. —American Three-high Mill, with 36-inch Rous. (Harbord and Hi m XXXII. (Puppe.) — Power required to Roll Rails about 35.S kg. per meter. For further data see Table XCVI. Output of Motors. Speed curve. r- RESULTS OF A. B. & a R. R. Co. DROP TESTS, JUn~D SUREACE mSPECTIOH OF RAILS POL i»i forme Jnalysis of Heals fe/ecfej LED DXJRmq %fcSrt^ffi%£U/&!Z li z„ 1 I Name ofCompany Pail it ■'■>.■:. 54 No. of 'Tons Received of each Classification. /ejected. I I i 1 1 No. of Pails Accepted No. of Pails 1 Ts 8\. No. of Pa I :,';,. ■ ■ III? Hi in lift Average Analysis j Average Analysis of Heats Accepted j of Heats Rejected 'o:L'!%td ll 1, ta&ESS f s No.l Specials No. 2 is! 1 '.: No.l Specials No. 2 11 J $1 1! £* P. 1 i\ Tons A B. c. * I it Pails A P r p 1 J J 1 1 '' * M it |M 1 \ I 1 J_ 1 * $ 1 | No. \.i. No No. No. sk^^ Ma.ng. PhOS Sit Sulpha m> Phos Si! Solplti / ° " " * ,. ' J " " " " " " " " " " " " " - •• "1 » ^r 2 | I H— 2 3 — t- 4 J r -j— — f— e 1 J „ 8 — 9 ■ — — • r~ 12 13 ■ « - r is i ■ m Grand Total . These two columns ire for office use 'everal rollings and shipments, and are 'o be removed on line 1'frem the finished <* NQTE - DROP TESTS TESTS AND INSPECTION. If Specials are not accepted, columns 8,9.10,11 and Drop Tests shall be made on pieces of rail rolled from the top of (a) Two pieces shall be tested from each heat of steel. If of Hie same heat. If two out of three of these second test pieces Z3.Z4-.Z5.26 should be omitted. the ingot, not less than four (4)ft. and not more than sixfelft. bng.from either of these test pieces breaks.a third piece shall be 'tested, break, the remainder of the rails of theheat will also be rejected each heat of steel. These test pieces shall be cut from the rail bar If two of the test pieces break without shorting physical defect Iftm out of three of these second test pieces do not break the next to either end of the top rail, as selected by the inspector all rails of the heat mil be rejected absolute//. If two of the test remainder of the rails of the heat mil be accepted provided they pieces do not break, all rails of the heat will be accepted as No 1 conform to the other requirements of these specifications as No 1 The test pieces shall be placed head upward on solid supports, five or No 2 classification, according as the deflection is less or or No. 2 classification, according as the deflection is less or more (5) in top radius, three (3.) ft between centers, and subjected to more, respectively, than the prescribed limit. respectively, than the prescribed limit. • impact tests, the tup failing free from the following heights: 70 lb. rail. left. &) If, however, any test piece broken under testy.shom (d) If any test piece, teste;does not break' but when nicked and 60,85 and 90 lb rail. 18ft. physical defect, the top rail from each ingot of that heat tested to destruction shows interior defect the fop rails from lOOlb.rail. 20ft. shall be rejected. each ingot of that heat shall be rejected. ' The test pieces which do not break under the first drop shall be nicked and tested to destruction. Cc) Additional tests shall then be made of test pieces selected by the Inspector from the top end of any second rails INDEX An, Ar 2 , Ar 3 points 426 Aberdare rails, effect of cold on 285 Adriatic Railway tie 102, 104 Affleck tie 104 Algoma Steel Company: rail mill 437, 438, 444 shrinkage allowed at , 444 teeming practice 399 Alloy steel (see Special steels). Alsace-Lorraine Railways, data on track. . . . 218 Aluminum : effect of, in casting steel 401, 405 in iron ore 364 America (see also American) : earl}' steel rails used in 2 length of rails used in 267 production of rails in 382 steel manufacturers of (see Association of American Steel Manufacturers). use of English rails in 2, 4 American (see also America and United States) : engines, examples of 32, 33, 34, 72 joints, examples of 264 rail mills, practice at 399, 438, 444 specifications for rails 463 speed of railway trains 21, 23, 27, 28 Steel Manufacturers, Association of (see Association of American Steel Manu- facturers), steel rails: examples of girder rails 19 T-rails, early 6 T-rails, present 10, 460 prices of 325 tie plates, examples of 122 type engine (see Eight-wheel type engine) . American cypress, resistance to pulling of spike 140 American Electric Railway Engineering Association, rail sections 19 American Forest Congress, ties 106 American Institute of Mining Engineers: blowholes 404 effect of recarbonizing 391 Gayley dry blast 360 American Institute of Mining Engineers: Lake Superior ores 351 piping in ingots 401, 409 relation between chemical composition and strength of rails, Dudley on 326 roasting iron ores 344 Sauveur on rail structure 429 American Locomotive Company: examples of modern locomotives . 32, 33, 34, 72 excess pressure of driving wheels 35 American McKenna Process Company, rerolling rails 459 American Railway Association: committee on standard rail and wheel sec- tions, report of 14 discard, investigation of 417 lettering rails from different parts of the ingot 416 rail sections, principles governing design of 16 proposed by 14 series A, description of 15 failures of 10 B, description of 15 test to determine piping 417 American Railway Engineering and Main- tenance of Way Association (see American Railway Engineering As- sociation). American Railway Engineering Association: classification of defective rails 10 comparison of rail failures of different sections 10 distribution of pressure to subgrade 185 drop testing machine, proposed by 290 tests 293 flow of rail head under wheel loads 205 grain size in head of rail 432 impact tests 64 report on flat spots on car wheels 56, 61 manufacture of rails, 363, 374, 378, 436 metal and composite ties 90 scleroscope 298 reports and records proposed by 10, 501 screw spikes 142 American Railway Engineering Association: size and spacing of ties 121 special steels 333, 339 specifications for rails 463 standard locations of borings for chemical analysis and tensile test pieces 512 statistics of defective rails 10 strength of head and web of rail 252 rail steel 304 stresses in the rail 210, 218 tests on flat spots in car wheels 61 joints 264 strength of rail steel 304 strength of wood 169 tie plates 133, 170 tree plantations for ties Ill unit stresses of different woods 168 American Railway Master Mechanics' Association: excess pressure of driving wheels 35 tire wear 197 American Society for Testing Materials : bibliography of impact tests 288 cupro-nickel steel 332 drop tests 288 ductility in rail steel 286, 287 experiments on repeated stress 278, 280 finishing temperature 434 hardness tests 298 Howe, on welding blowholes 404 ferrite grains 427 impact tests 288 influence of titanium on segregation 405 manganese sulphide in steel 390 manufacture of car wheels 57 specifications for girder rails 491 T-rails 463,491 stremmatograph experiments 236 Talbot, rolling practice in England 434 tests on nickel steel 332, 334 American Society of Civil Engineers: committee on rail sections 6 finishing temperature in rails 7 rail section 6 difficulty in rolling heavier rails. . . 7, 14, 435 failures of 10 necessity for rolling at high tem- peratures 435 strains produced in, by straightening. . . 445 report on early steel rails 4 specifications for rails, bibliography of . . . . 494 American Society of Mechanical Engineers: Bessemer process 366 electric locomotives 74 pressure of locomotive drivers 32, 62 wire tests of Professor Goss 62 American Wood Preservers' Association, report on timber supply 113 Amsler-Laffon machine for testing hardness.. 301 Analysis : converter metal 374 copper alloys used by Ball and Wingham. 331 early English rails 326 ferromanganese 374, 380 ferrosilicon 380 ferrotitanium 405 iron ores 363, 364 location of standard borings for (American Railway Engineerirg Association) . . . 512 mixer metal 380 specification for (see Specifications). steel, Bessemer 11, 253, 310 electric 385 manganese 333 nickel 333 open hearth 310 titanium 340, 406 Angle bars (see Joints). Angle: fishing (see Joints). of friction of soils 314 of incision in rolling 457 of repose of various soils 314 Ann Arbor Railroad, concrete ties on 105 Annealed rails 208 Annealing, effect of, on special steels . . . 336, 337 Anthracite coal in blast furnace 361 Archduke Albrecht Steel Works at Carl- shtitte 3 Arnold, J. O.: causes of rupture in steel 271 influence of bismuth on copper 271 Arsenic, effect of, in steel 330 Articulated compound engine (see Articu- lated engine). Articulated engine: classification of 29 dimensions of 34, 72 typical dynamic wheel loads 73 weights of 34,72 Ash, physical properties of 164 Association of American Steel Manufacturers : chemical specifications for rails 342 drop testing machine 290 specifications for rails 342, 463 Association of Engineering Societies, Howard, on rail failures 203 Aston, on cupro-nickel steel 332 Atchison, Topeka and Santa Fe Railway: effect of subgrade on track 313 rail section 461 screw spikes on 141 527 Atchison, Topeka and Santa Fe Railway: speed of trains 25, 26, 27, 28 Atlanta, Birmingham and Atlantic Railroad, size and spacing of ties 121 Atlantic City Railway, speed of trains, 23, 25, 26, 28 Atlantic Coast Line Railroad: size and spacing of ties 121 speed of trains 24 Atlantic type engine: allowable axle loads 322 classification of 29 description of 21 dimensions of 32, 72 effect of excess balance and angularity of main rod 40, 70 pressure rounding curve 259 rail stresses caused by 212 speeds of 21, 24, 25, 26, 70 strength of track required for 322 typical dynamic wheel loads 72 weight of rail required for 322 weights of 32, 72 Atlas, Barrow and Dowlais, steel rails made by 2 Austenite 427 Australia, length of rails used in 267 Austria, early steel rails 3 Austrian State Railways, hardness tests on 302 Axle loads : cars 85, 89 dynamic (see Dynamic). effect of size of wheel on . 202 given in modern bridge specifications 211 increase in 15, 30 locomotives, electric 74, 79, 80 steam 31, 32, 33, 34, 72 maximum allowable, on rail 319 used on Paris, Lyons and Mediterranean Railway 19 Axle spacing: effect of, on load 247 s of rail for different. ..'.... 319 Back driver (see Driving wheels). Baggage car 84 Bairstow and Stanton, experiments on re- peated stress 281 Baker, Benjamin, experiments on repeated stress 282 Bald cypress, physical properties of . . . . 164, 168 Baldwin Locomotive Works, progress in loco- motive building 30 Ball, influence of copper on steel 331 Ball pressure tests 300 Ballast: bearing power of 179 effect of dynamic load on 189 Cuenot's experiments on 172 depression of tie in, U. S. Government experiments 219, 222, 233 depression of track in 172, 176, 189 depth required for different classes of track 317 distribution of load to subgrade 180, 185 experiments on, in Germany 180 frozen, effect of, on bending moment of rail 229,288 frozen, tests on, by U. S. Government 225 influence of kind of, on stresses in rail .... 229 Pennsylvania Railroad tests 184 weights of 316 Baltic fir (see also Fir), force required to pull spike from 140 Baltimore and Ohio Railroad: articulated compound engine 34 chrome-nickel rails on 333 electric locomotives 79 impact tests on bridges 64 ore docks 357 rail section 461 size and spacing of ties 121 speed of trains 24, 28 titanium rails on 339 use of scleroscope on 298 Bangor and Aroostook Railroad, size and spacing of ties 121 Barnes, rail pressures of locomotive driving wheels 32 Base rail: broken (see Broken base). indirect pressure used in rolling. . . . 457 principles governing design of 16 strength of steel from 306 wheel: of cars 85, 89 of electric locomotives 79, 80 of steam locomotives 32, 33, 34, 72 Basquin, O. H., endurance tests 280 Bavarian State Railways: arrangement of joints on 144 data on track 218 spikes used on 144, 145 tie plate 128, 132 weight of rail on 144 Bearing power (see Supporting power). Beck, effect of cold on rails 285 Beech: force required to pull spike from 140, 152 ties, amount purchased in the United States 156 Beech ties, cost of 156 on French Eastern Railway .... 117 Belgian State Railways, rail and tie plate, 125, 126 Bell, Sir I. Lowthian: cost of transporting ore 349 depression of rails at different speeds 190 early iron rails 1 Bending moment: maximum for different loadings of rail. . . . 320 rail, calculation of 239 determined by Love 241 effect of joint on 262 unequal tie pressure on . . 239, 288 proposed solutions of 210 stremmatograph tests of 236 U. S. government experiments 218 tie 171, 177, 179 tie plate 122, 170 Bending strength of wood: effect of moisture on 169 steaming on 158 treatment on 158 in natural state 158, 164, 166, 168 Bending tests on worn rails 205 Benjamin, Professor C. H., flat spots on car wheels 60 Berlin-Zossen line, speed of electric loco- motives 27 Bessemer, Sir Henry, origin of the Bessemer Bessemer: comparison of, with open hearth process. . 380 description of plant 369 early rails, in America 3 invention of process 366 process, description of 370, 374 economies possible in 383 steel, analysis of 11, 253, 310 segregation in 405 strength of 309, 310 rails, amount in tracks of American railroads 11 branding 447 ductility of 287 failures of 10 hardness determined by sclero- scope 299 prices of 325 production of 382 rolling tests on, at Watertown Arsenal 420 specifications for (see Specifi- cations) . Steel Works at Troy, early steel rails 4 Bessemer and Lake Erie Railroad, steel ties on 90 Bethlehem Steel Company: chrome nickel steel rails 333 rail mill 438, 444 shrinkage allowed at 444 teeming practice 399 use of iron with high copper 332 Bibliography : of chemical composition 343 of impact tests 288 of joints 268 of literature on steel manufacture (see Preface). of piping and segregation 418 of rail specifications 494 Birch ties: amount purchased in the United States. . . 156 cost of 156 Birkinbine, John, roasting iron ores 344 Bitternut hickory, physical properties of . . . . 164 Bituminous coal in blast furnace 361 Black locust, planting, for tie timber 109 Bland, J. C, stresses in the rail 211 Blast furnace: description of 357 dry blast 360 fuel used in 361 location of plant , 345 operation of, at Gary 364 Maryland Steel Company 363 performance of, with dry blast 361 stoves 359 typical examples of 357 Bled ingots, specifications for 473 Blessing, concrete tie 104 Bloom: elimination of defects in, early mill practice 434 entering rolls 421 size of 438 Blooming: passes, reduction in 437, 438 practice at American mills 438 Blowholes : Brinell's experiments on 402 caused by iron oxide 389 description of 401 effect of fluid compression on 416 in titanium steel 406 means for preventing 401 Blum: report on speed of trains as affecting track . 28 stresses in the rail 217 Bolt, track (see also Joints) : holes, arrangement of (see Joints), specifications for (. drilling). 529 Bolt, track, pull required to tighten 260 strength of 260 used on English bull head rail 19 Bonzano joint 264 Borings, location of standard, for chemical analysis, American Railway Engineer- ing Association 512 Boston and Albany Railroad: angle bar tests 260 early steel rails on 2 track experiments on, by U. S. Govern- ment 218, 225 Boston and Lowell Railroad, granite ties on 90 Boston and Maine Railroad: rail section 10 failures 10 size and spacing of ties 121 tests on locomotive springs 52 Boston and Providence Railway, early steel rails on 2 Box car 81 Brakes, effect of application of, on locomo- tive springs 52 Branding : practice at different mills 447 specifications for (see also Specification in question) 477 Breuil, P., impact tests 292 Bridge: effect of velocity of load on 69 impact on, caused by moving train 64 specifications, impact allowed in 210 limiting weights on axles. . . 211 Brinell: ball pressure tests 300 experiments on blowholes 402 hardness test 300 British Standards Committee: bull head rails 19 flat bottom rails 19 rail sections 19 specifications for bull head railway rails . . 484 flat bottom railway rails . 488 tramway rails 19 Broken base: classification of, American Railway Engi- neering Association 10 due to defects in casting 390 photographs of typical failures 11 rail failures, six months ending April 30, 1909 10 Broken rails: caused by defective equipment 57 classification of, by American Railway Engineering Association 10 Broken rails: failures, six months ending April 30, 1909 10 photographs of typical failures 11 Broken stone: ballast (see Ballast). weight of 316 Brown hoist machine for unloading ore 357 Brown, John, and Company: chemical composition of rails rolled by.. . . 326 early steel rails 4 rails rolled for Ashbel Welsh 5 Brown, J. P., on use of catalpa for ties 109 Brunson concrete tie 104 "B. S." rail sections (see British Standards Committee). Buffalo, Rochester and Pittsburgh Railway, size and spacing of ties 121 Buhrer: composition tie 96 concrete tie 97, 105 steel tie 96 Bull head rail (see also British Standards Committee) : specifications for 484 types of 19 Burbank tie 104 Burden of blast furnace 363, 364 Bureau of Forestry (see U. S. Forest Service). Bureau of Standards, magnetic testing of rails 303 Burgess, on cupro-nickel steel 332 Burlington (see Chicago, Burlington and Quincy Railroad). Calcination of iron ore 344 Caledonian, Lancashire and Yorkshire Rail- way, early steel rails on 3 Caledonian Railway: rail fastenings on 147 speed of trains 28 Camber, amount of, in rails 444, 477, 482 Cambering machine 444 Cambering, specifications for (see Specifi- cations). Cambria Steel Company: early steel rails 3 handling ore at 363 mixer used at 365 oil tempered joints 266 ores formerly used at 344 rail mill 438,444 shrinkage allowed at 444 teeming practice 399 tests to detect pipes 469 titanium steel rails 340 530 Camden and Amboy Railroad, first use of T-rail 6 Camden and Atlantic Railroad, speed of trains 25 Campbell, H. H.: experiments on nickel steel 335 rolling 430 Campbell tie 105 Canada, length of rails used in 267 Canadian Pacific Railway: indentation test 300 rail section 461 speed of trains 24 ten-wheel type engine 33 Canadian Society of Civil Engineers: Dutcher on indentation test 300 long ties used on Muskeg swamp 188 Capillary attraction, movement of water by, in subgrade 314 Carbon : content in rails: increase in following Dudley's experi- ments 328 of Bessemer steel 11, 253, 310 of open hearth steel 310 of special steel (see Special steels) . specifications for (see also Specifications), 328, 342, 466 effect of, in steel 329 on ductility of rail steel 287 iron diagram 427 modification of, for low phosphorus 466 segregation of 409 Carbon dioxide, evolution of, in cooling steel 401 Carbon-iron diagram 427 Carbon monoxide, evolution of, in cool- ing steel 401 Carbonic anhydride, compression of the ingot by means of 415 Carnegie Library of Pittsburgh, bibliography of rail specifications 494 Carnegie Steel Company: blast furnaces 361 chemical composition of rails 328 dry blast at 361 nickel steel rails 333 rail mill 438, 444 shrinkage allowed at 444 steel ties in tracks at Duquesne Plant 94 teeming practice 399 titanium steel rails 340 Carnegie steel tie 90 Cars: allowable wheel loads of 322 dynamic augment of wheel pressure. ... 85, 89 Cars: strength of track required for 322 weight of rail required for 322 weights of 85, 89 Cartesian coordinates, stress-repetition curves drawn to 281 Cast iron: manufacture of 357 wheel, effect of, on rail 195 Casting: effect on steel 390, 395 fluid compression during 410, 415 the ingot 395 Casting ladle: effect of agitation of steel in 390 example of 389 Catalpa : force required to pull spike from 139 planting for tie timber 109 Cedar: physical properties of 164, 168 ties, amount purchased in the United States 154, 156 cost of 154, 156 Cedar elm, physical properties of 164 Cell (see Grain). Cementite 427 Census, United States: distribution of lumber products in the United States 108 ties purchased in the United States 156 Center of gravity in locomotives 74, 259 Central of Georgia Railway, size and spacing of ties 121 Central Railroad of New Jersey: size and spacing of ties 121 special steel rails on 333 speed of trains 24, 28 Centrifugal force: of counterbalance 38 of locomotive when rounding curve 259 of wheel on irregular track 45 Chair used with bull head rail 19 Chanute, Octave: investigation of proper design of rail 6 report on steel rails 5 Chapin ore 364 Charcoal in blast furnace 361 Charge of blast furnace 363, 364 Charpy, G., impact tests 292 Chemical composition: bibliography of recent literature on 343 comparison of early and recent, in rails. . . 328 Dudley's formula 327 effect on physical properties of steel (see Element in question) . Chemical composition : effect on rail breakages in coll weather . . . 286 form for reporting, American Railway En- gineering Association 503 increase in hardening constituents in rails . 328 location of standard borings for analysis, American Railway Engineering Association 512 of Bessemer steel 11, 253, 310 of different steels (see Analysis). of early rails 326 of joints 234, 266 of open hearth steel 310 of special steels (see Special steels), specifications for, in rails (see also Specifi- cation in question) 328, 342, 465 Chemins de Fer d'Orleans (see Orleans Rail- way) . Chemins de Fer de l'Est (see French Eastern Railway). Chemins de Fer de l'Etat (see State Railways of France). Chemins de Fer de l'Ouest (see Western Rail- way of France). Chemins de Fer de Paris a Lyon et a la Medi- terranee (see Paris, Lyons and Medi- terranean Railway). Chemins de Fer du Midi (see Southern Rail- way of France) . Chemins de Fer du Nord (see Northern Rail- way of France). Chenoweth concrete tie 104 Chesapeake and Ohio Railway articulated compound engine 34 Chestnut : force required to pull spike from 139 ties, amount purchased in the United States 154, 156 cost of 154, 156 Chicago and Alton Railroad: concrete ties on 99, 105 early steel rails on 2 Chicago and Eastern Illinois Railroad, size and spacing of ties 121 Chicago and North Western Railway: concrete ties on 105 early steel rails on 2, 4 new rail section 462 size and spacing of ties 121 speed of trains 24, 26, 28 ten-wheel type engine 33 Chicago, Burlington and Quincy Railroad : concrete ties on 104 plantations for tie timber Ill prairie type engine 33 rail section 10, 461 Chicago, Burlington and Quincy Railroad : rail section failures 10 size and spacing of ties 121 speed of trains 24, 25, 26, 27 track experiments 219 Chicago Great Western Railroad, size and spacing of ties 121 Chicago, Indiana and Southern Railroad : consolidation type engine 34 size and spacing of ties 121 Chicago, Indianapolis and Louisville Rail- way, size and spacing of ties 121 Chicago Junction Railway, concrete ties on. . 104 Chicago, Milwaukee and Puget Sound Rail- way, size and spacing of ties 121 Chicago, Milwaukee and St. Paul Railway: excess pressure of driving wheels 36 fiat spot in engine wheel 56 Pacific type engine 32 size and spacing of ties 121 speed of trains 25 Chicago, Rock Island and Pacific Railway: Atlantic type engine 32 early steel rails on 2 size and spacing of ties 121 Chicago, St. Paul, Minneapolis and Omaha Railway, size and spacing of ties. . . . 121 Chrome-nickel steel rails: production of 341 use of 333 Chromium: effect of, in steel 334 in combination with nickel 335 steel rails, production of 341 Cincinnati, Hamilton and Dayton Railway, size and spacing of ties 121 Cinder ballast (see Ballast). City cars 88 Clamer, copper and nickel in steel 332 Clary tie plate 122 Classification: of locomotives 29 of track 317 Whyte's system 29 Clausen, L. R., example of flat wheels 56 Clay: angle of friction of 314 bearing power of 187 Cleveland, Cincinnati, Chicago and St. Louis Railway: plantations of tie timber 112 size and spacing of ties 121 Cleveland, Painesville, Ashtabula Railway, car used on 88 532 Coal: cars (see also Cars), effect of heavy, on track 82, used in blast furnace Coefficient : of ballast of friction of soils of slip in driving wheels 198, of yielding in ballast on German railways. Coes and Howard, experiments on rocking of engine Cogging mill 437, Cogging rolls used in Puppe's tests 448, Coke car Coke used in blast furnace 361, 363, Colby, A. L., experiments on nickel steel. . . . Cold: defective tires due to effect of, on strength of rail rolling of head of rail caused by wheel rolling of rails i shortness in steel I straightening press < straightening rails 4 work, effect of, on structure of steel . 424, i Collet trenail 148, ] Colorado and Southern Railway, size and spacing of ties ] Colorado Fuel and Iron Company: rail mill 438,' shrinkage allowed at l . Columbia type engine, classification of Composite ties used in Cuenot's experi- ments ] Compression : fluid, of ingot 410, < modulus of, at point of contact of wheel and rail 194, ] effect of bearing surface on.. . 1 strength of special steels (see Steel in question) . strength of steel ] effect of chemical composition on (see Element in question). strength of wood 158, 165, 167, 168, 1 effect of treatment on ] Concrete ties: (see also Tie in question) 97, 1 service tests on ] Cone pressure tests i Conical tires Connecticut River Railroad, early steel rails on Consolidation type engine: allowable axle loads c Consolidation type engine: classification of 29 dimensions of 34, 72 effect of excess pressure and angularity of main rod 44, 70 pressure rounding curve 259 rail stresses caused by 228 speeds of 70 strength of track required for 322 tests on driving wheel springs 52 typical dynamic wheel loads 73 U. S. Government experiments with 228 weight of rail required for 322 weights of 34, 72 Continuous : girder, rail as 189, 240, 247 joint 264 process of making steel 375 rails 267 record of rail failures, form for reporting graphically 523 Conversion of iron into steel 366 Converter (see Bessemer). Converter metal, analysis of 374 Cooling curve of different substances. . . 425, 426 Coombs, R. D., on concrete ties 104 Cooper, Hewitt and Company, first open hearth furnace in America 375 Copper: cooling curve of 425 effect of, in steel 331 granular structure 270 Cornwall irons, high copper in rails made from 332 Corrugations of rails 209 Cort, early methods of making steel 366 Cost: of Bessemer compared to open hearth process 383 of forest land . . . . ' 114 of plantations for tie timber Ill of rails, 1855 to 1910 325 ferrotitanium 341 rerolling 459 of ties, annual charge of 115 treated 115 in the United States 154, 156 of track of German railways 218 with screw spikes 142 of transporting ore 349, 352 Coiiard, depression of ties in ballast.. . . 172, 190 Counterbalance pressure : absence of, in electric locomotives 78 amount of, for different types of engines 35, 70 calculation of 35 533 Counterbalance pressure: effect of inertia of track on stresses pro- duced by 69 on bridges 68 tire wear 202 Professor Goss' experiments on 62 Cow oak, physical properties of 164 Crandall, Professor, experiments on steel rollers, on steel plates 194 Creeping of rails 153 Creosote treatment (see Treated Ties). Crescent breaks in flange: effect of casting on 390 examples of 11 Creusot rails, effect of cold on 285 Creusot, steel works, early steel rails 3 Critical point, effect of rolling below 427 Crop (see Discard). Cross ties (see Ties). Crushed head: classification of, American Railway En- gineering Association 10 effect of casting on 390 investigation of 391 photographs of typical failures 11 rail failures, six months ending April 30, 1909 10 Crushing strength (see Compression). Crystal (see Grain). Cuban pine, physical properties of 164 Cuenot, G.: advance wave of rail 223 experiments on ties 172 profile of rail 46 Cupola for melting pig iron 366 Cupro-nickel steel 332 Curve: comparison of rail failures on, with tangent. 10 elastic, of rail 241, 242 of tie 172, 176, 177 horizontal pressure exerted by engine when rounding 259 relation of coning of wheel to 7 Cushing, W. C: design of screw spike proposed by 147 discard of ingot 417 discussion of screw spikes 142 on ties (translation of M. Cuenot 's experiments) 172 Cylinder: compression modulus of surface of 193 size of, on modern steam locomotives, 40, 41, 42, 43, 44 Cylindrical tires 6 Cypress : force required to pull spike from 140 Cypress: physical properties of 164, 168 ties, amount purchased in the United States 154, 156 cost of 154, 156 De Paris a Lyon et a la Mediterranee (see Paris, Lyons and Mediterranean Rail- way). Decapod engine: classification of 29 example of 31 Defective equipment: broken rails caused by 57 due to excessive loads . . • 85 small diameter of wheel 202 effect of, on track 57 examples of long flat spots in wheels ... 56, 57 lack of roundness in chilled car wheels. ... 58 Defective rails: classification of, by American Railway Engineering Association 10 for six months ending April 30, 1909 10 forms for reports and records of, American Railway Engineering Association 506, 512 forms for reports and records of, chart for . 523 forms for reports and records of, used on Harriman Lines 524 on American railroads 10 photographs of typical failures 11 Defective wheels (see Defective equipment). Deflection: in drop test, specifications for 470, 486 of driving wheel springs 48, 49, 53 of head of rail under eccentric load . . 255, 257 of rail, comparison of worn and un- worn 204, 205 in drop test 292, 294, 470, 486 in track, amount of 190, 233 in track, effect of, on stress in rail 243 Deflectometer used by Turneaure in impact tests 64 Delaware and Hudson Company: articulated compound engine 34 consolidation type engine 34 80-lb. rails used by, in 1893 7 management of timber lands 113 size and spacing of ties 121 Delaware, Lackawanna and Western Rail- road : Mogul type engine 34 plantations of tie timber Ill size and spacing of ties 121 speed of trains 25 ten-wheel type engine 33 534 De L'Est (see French Eastern Railway). De L'Etat (see State Railways of France). De L'Ouest (see Western Railway of France). Denver and Rio Grande Railroad, size and spacing of ties 121 Denver, North Western and Pacific Railway, ten-wheel type engine 33 Depression (see also Deflection) : of tie in ballast, amount of 172, 176, 189 effect of, on stress in rail. 243 of track, U. S. Government, experiments on 218 Design : of rail 6, 17, 458 of rolls 457 of track 323 Detroit River Tunnel Company's loco- motive 75, 80 Dickerson, S. K., tests on chilled car wheels 57 Dining car 84 Direct pressure in rolling 456 Direct process of making steel 365 Discard : amount of, necessary 417 report of American Railway Association on 416 required on compressed ingots 415 specifications for (see also Specification in question) 473 Docks, ore 348, 350, 357 Dolomite used in blast furnace 363 Dominion Iron and Steel Company: rail mill 438, 444 shrinkage allowed at 444 D'Orleans (see Orleans Railway). Double-headed rail: examples of 19 specifications for 484 Douglas fir (see also Fir), physical proper- ties of 166, 168 Douglas spruce, physical properties of 164 Dowel: increased resistance due to use of, in ties. 152 use of, with screw spike 142, 150 Drainage : effect of water on gravel ballast 187 necessity of, for subgrade 314 Draw bar: constant pull on, of electric locomo- tives 78 effect of, on pressure of drivers 71 pull in Mallet locomotive 22 Drill test for hardness 303 Drilling, specifications for, in rails (see also Specification in question) 477 Driving wheels (see also Axle and Wheel) : coefficient of slip of 198, 199 effect of position of, on allowable load .... 322 increase in pressure on rail due to excess balance and angularity of main rod. . 35, 70 increase in pressure on rail due to irregu- larities in the track 45, 71 increase in pressure on rail due to rocking of engine 54, 71 increase in weight on 15, 30 springs (see Springs). weights on, electric locomotives 79, 80 steam locomotives . . 31, 32, 33, 34 wheel base, electric locomotives 79, 80 steam locomotives . . 32, 33, 34, 72 Drop test: bibliography of 288 comparison of deflections obtained with different machines 291 deflections obtained in 291, 294 description of recent machines 289 energy dissipated in 293 form for reporting results of, American Railway Engineering Association .... 505 losses in 293 machine, standard 290 measurement of ductility in 287 specifications for 290 specifications for (see also Specification in question) 470 theoretical considerations of 293 Dry blast (see Gay ley). Ductility: in rail, specifications for 470, 480 steel 287 in special steels (see Steel in question). of steel, effect of chemical composition on (see Element in question). effect of cold on 286 effect of titanium on 287 Dudley, C. B.: proposed formula for chemical composi- tion of rails 327 tests on relation between chemical com- position and wearing of rails 326 Dudley, P. H.: casting steel 388 depression of track in ballast 190, 213 design of new section with large fillet 462 ductility in rail steel 286 dynamic augment to wheel load 212 effect of cold on rails 287 draw bar pull on wheel pressure . . 71 friction in splice bars 261 grains per square inch in rail steel 424 joint 265 Dudley, P. H.: lettering rails from ingot 416 reheating furnace, effect of, on ingot 400 section of rail 10, 462 failures 10 stremmatograph tests 212, 236 tonnage service of wheels and rails 202 wear of rails 328 Duguet, Captain, impact tests 292 Duluth and Iron Range Railroad, ore dock 348 Duluth, Mesabi and Northern Railway, ore docks 351 Duluth, South Shore and Atlantic Railway, size and spacing of ties 121 Dumas, report on nickel steel 336 Du Midi (see Southern Railway of France). Dummy pass 443, 444 Du Nord (see Northern Railway of France). Duplex process for making steel 388 Duquesne joint 264 Dutcher, indentation test 300 Dynamic : augment of wheel load: amount of, for cars 85, 89 for electric locomotives .... 78 for steam locomotives. ... 71, 72 assumed by Bland 211 Dudley 212 causes of 32 due to excess pressure of counter-bal- ance and angularity of main rod 35 flat spots in wheels 54 impact 68 irregularities in track 45 rocking of engine 54, 71 velocity of load 70 load, effect of, on driving wheel springs ... 54 track 189 tests on ties 175, 190 typical, load diagrams for cars 85, 89 electric engines. 78 steam engines. 72, 73 wheel load allowable for 1004b. rail 247 wheel loads for different weights of rail and axle spacing 319 E-60 loading 211 Earth: angle of friction of 314 bearing power of 313 East Coast Railway of England, speed of trains 25, 28 Edgar Thomson Works: early use of mixer at 365 fluid compression of the ingot 415 Egyptian State Railways, rail section 19 Eight- wheel type engine: classification of 29 coupled, classification of 29 description of 21 effect of excess balance and angularity of main rod 35 rail stresses caused by 219, 235, 236 stremmatograph tests with 236 U. S. Government experiments with.. 219, 228 wear of tires 199 El Cuero ore used at Maryland Steel Company 363 El Paso and Southwestern System, size and spacing of ties 121 Elastic curve: calculation of, for 100-lb. rail 242 of rail, calculation of, by Love 240 of ties 172, 176, 177 Elastic limit: definition of 310 effect of repeated loads on 311 effect on structure of metals of straining beyond 273 necessity for high, in rail head 208 of rail at point of contact with wheel . . 194, 195 of rail steel 306 relation of breaking strength to, under repeated stress 273, 278 relation of, to working load 312 of special steels (see Steel in question). Elasticity, modulus of: of steel 225, 241 of wood 158, 166, 168 Electric: cars 87, 88, 322 furnace: description of 383 steel from, analysis of 385 production of 341 strength of 386 locomotives: comparison of, with steam 74 dynamic augment to wheel load (see Dynamic). general characteristics of 79, 80 pressure of, rounding curve 257 speeds of 27, 29, 79, 80 typical dynamic load diagrams 78 magnet for loading rails 446 motor for rolling mills: advantages of 459 use of, at Gary 437 railway : cars 87, 88, 322 corrugations in rails 209 536 Electric : railway: cross-ties purchased by 154, 156 rails, specifications for 491 use of manganese in 339 used on 19 roaring rails 209 weight of rail for various axle loads .... 322 welded joints on 267 steel rails, production of 341 Elgin, Joliet and Eastern Railway, concrete ties on 105 Elm, physical properties of 164 Elm ties: amount purchased in the United States.. . 156 cost of 156 Elongation: effect of chemical composition on (see Element in question). effect of size of grain on 424 in electric steel 386 in rail, specifications for 470, 480 in rail steel 306 determined in drop testing machine .... 287 in rolling, Puppe's tests 456 in special steels (see Steel in question). under repeated stress 280 Elsass-Lothringen State Railways: arrangement of joints on 144 rail and tie plate 130 spikes used on 144, 145 weight of rail on 144 Empire State Express, speed of 23 Engineering Standards Committee (London) : bull head rail 19 flat bottom rail 19 length of rails 268, 485, 489 rail sections 19 specifications for bull head railway rails. 484 flat bottom railway rails . 488 tramway rail 19 Engineers' Club of St. Louis, Johnson on compression moduli 193 Engines (see Locomotive). England (see English). English: chemical composition of early steel rails . . 326 early steel rails 2, 326 iron rails, life of 2 prices of 325 length of rails 268 practice in rolling rails 434 rail fastenings 19, 147 rail mills, hot straightening at 446 reheating furnace 398 screw spikes 19, 146, 147 English : specifications for rails 484, 488 speeds of railway trains 24, 25, 28 steel rails, prices of 325 used in America 2, 4 three-high rail mill 437 trenails used on, railways 19, 146, 147 types of rails 19 weights of rails used on, railways 19 Erakoff, effect of cold on rails 285 Erie Railroad: chrome-nickel rails on 333 early steel rails on 4 size and spacing of ties 121 speed of trains 25, 26 Europe: rail fastenings used in 144 rails used in 19, 125 types of tie plates 125 Eutectoid steel 427 Ewing, J. A., experiments on repeated stress 273 Excess balance (see Counterbalance pressure). Exhausted metal in head of rail 204 Extensometer used in Turneaure's impact tests 64 Extreme fiber stress: allowable in rail 312 bending moments corresponding to 248, 320 in 100-lb. rail, calculation of 239 in rail, determined by Bland 211 Freeman 211 Government tests. . 218 Selby 210 on German railways." 218 shown by stremmatograph. . . . 212, 236 in tie 171, 179 Factor of safety : amount of, in different structures 311 in rails 312 Failures: rail (see Defective rails). wheel (see Defective equipment). Farlington forest 110 Fastenings, rail (see Joints). Fatigue of metal: in head of rail 204, 284 under repeated stress 270 Faustmann's formula for productivity of woodlands 114 Fay, Henry, manganese sulphide in steel. . . 390 Felt: tie plate on French Eastern Railway 132 London and North Western Railway 19 Felton, S. M., increase in loads on engine drivers 30 Feodossieff, effect of cold on rails 285 Ferrite 427 Ferromanganese (see also Recarbonizing) : amount added to recarbonize 374, 380 analysis of 374, 380 manganese in steel due to use of 330 Ferrosilicon 380 Ferrotitanium (see Titanium). Ferrule, oak, for spike 19 F6ry pyrometer 434 Fiber stress (see Extreme fiber stress) . Finishing : pass 437, 438 specifications for, in rails (see also Specifi- cation in question) 477 Finishing temperature : effect of, in rolling 430 in A.S.C.E. rails 7, 435 in English rails 435 specifications for (see also Specification in question) 475 Fir: force required to pull spike from 140 physical properties of 166, 168 ties, amount purchased in the United States 154, 156 cost of 154, 156 Fish bolt (see Bolt). Fishing angles of rail: determined by Chanute 6 principles of design of 6, 17 Fishplate (see Joints). Fissures, transverse, in head of rail 203 Flange, rail (see Base, rail). Flat bottom railway rails: specifications for 488 types of 19 Flat car 82 Flat spots in wheels : American Railway Engineering Asso- ciation, experiments with 61 broken rails caused by 57 effect of inertia of track on stresses pro- duced by 68 example of, on the Chicago, Milwaukee and St. Paul Railway 56 excess pressure caused by 54 M. C. B., rule for length of 56 Professor Benjamin's apparatus for testing 60 Professor Hancock's mathematical in- vestigation of 55 Florida East Coast Railway: concrete ties on 105 size and spacing of ties 121 Flow of metal in head of rail: classification of, by American Railway Engineering Association 10 effect of, on bending properties of rail .... 204 wheel load on 205 photographs of typical failures 11 rail failures, six months ending April 30, 1909 10 Flux used in blast furnace 361 Flywheel of rolling mill, energy in 459 Foppl, experiments on repeated stress 282 Force, H. J., effect of copper on steel 332 Forest: original, of the United States 106 wasteful cutting of, for ties 116 Forest Service (see U. S. Forest Service). Forestry: application of methods to growing tie timber 114 Faustmann's formula 114 original forests in the United States 106 plantations for ties 109 Forney coupled engine, classification of. . . . 29 Forney, M. N., report on steel rails 5 Forsyth, Robert: phosphorus in rail steel 465 piping of ingots 399 transferring ladle 390 Four-wheel engine: classification of 29 coupled, classification of 29 Fowler, G. L.: effect of repeated stress on rails 278 experiments on contact between wheel and rail 195 France (see French). Freeman, F. B.: reaction of tie in ballast 191 stresses in the rail 211 Freight car (see Cars). Freight locomotives (see Locomotives). French: early screw spikes 141 steel rails 3 rail fastenings 143, 144 screw spikes 143, 144 speeds of railway trains 24 tie plates 132 tie plug 149 types of rails 18 weights of rail used on, railways 18, 144 French Eastern Railway: arrangement of joints on 144 early screw spikes used on 141 half-round ties on 117 screw spikes on 143, 144 538 French Eastern Railway: section of rail 18 tie plate 132 tie plug 149 weight of rail on 18 French Government, fluid compression of ingots required by 415 Friction, coefficient of, for earth and gravel . 314 in joints: effect of, on rail stresses 262 tests on 260 of soils, angles of 314 Front driver (see Driving wheels). Frost (see also Cold): effect of, on depression of track 233 on rail breakages 288 Ft. Worth and Denver City Railway, size and spacing of ties 121 Fuel used in blast furnace 361 Furnace: blast (see Blast furnace). cupola 365 electric (see Electric). open hearth (see Open hearth). Gagging, effect of, on rail 445 Gagging press 445 Galvanized screw spike 19 Galveston, Harrisburg and San Antonio Railway: concrete ties on 105 size and spacing of ties 121 plantations of tie timber Ill Gary: blast furnaces at 358, 361 general arrangement of plant 361 open hearth furnaces at 378 rolling mill practice 437, 438, 444 shrinkage allowed at 444 soaking pits at 397 strength of steel from 306 teeming practice 399 Gas electric car 86 Gas in molten steel 366, 401 Gay ley dry blast : at Bessemer converter 389 description of, for blast furnace 360 General electric gas electric car 86 Georgia Railroad, size and spacing of ties . . . 121 German : electric steel 385 experiments on ballast 180 rolling mills 447 rail fastenings 144, 145 rails 19 German: screw spikes 144, 145 speeds of electric locomotives 27, 29 tests on tie plates 133 tie plates 125 track, data on 218 weights of rail used on, railways 19, 144 Germany (see German). Gibbs, George, electric locomotives 74 Girder rail (see Street railway). Goldie tie plate 122 Gondola car 82 Goss, Professor, tests on counterbalance pressure 62 Grab bucket for unloading ore 357 Grade, effect of changes in, on wheel pres- sure 45 Grading ore 344 Grain: changes in, under repeated stress 273 effect of rolling on 427 on strength of steel 272, 424 temperature on 427 number in rail steel 424 size of, in head of rail 392, 394, 424, 431 structure of different metals 270 Grand Duchy of Baden State Railways, early screw spike used on 140 Grand Rapids and Indiana Railway, size and spacing of ties 121 Grand Trunk Railway: effect of cold on steel rails 4 electric locomotives 80 size and spacing of ties 121 Granite ties 90 Granular structure (see Grain). Gravel : angle of friction of 314 ballast (see Ballast). weight of 316 Gravity: center of, in steam and electric locomo- tives 74 effect of, on wheel on irregular track 47 specific (see Specific gravity) . Great Britain (see English). Great Central Railway (of England), speed of trains 28 Great Eastern Railway (of England), rail fastenings on 147 Great Lakes (see Transportation). Great Northern Railway: accident on, at Sharon, N. D 325 electric locomotives 80 ore dock 350 size and spacing of ties 121 539 Great Northern Railway (of England) : rail fastenings on 147 speed of trains 24, 28 Green ash, physical properties of 164 Grooved rail: examples of 19 specifications for 491 Guerhard, effect of cold on rails 285 Gum: physical properties of 164, 170 plantations of, for tie timber 112 ties, amount purchased in the United States 156 cost of 156 Hadfield: experiments on nickel steel 334 manganese steel 336 Half-round tie 116 Hancock, Professor, flat spots in wheels .... 55 Hansen steel tie 94 Harbord, influence of arsenic on steel 331 Hardness tests: Brinell's ball test 300 cone pressure test 301 indentation test 300 Keep drill test 303 sclerometer, of Turner 302 scleroscope 298 Hardy catalpa: force required to pull spike from 139 use of, for tie plantations 109, 112 Harmet process for compression of ingot 411, 415 Harrell tie 104 Harriman Lines: chart of rail failures 524 specifications for rails 463 Harrison, T. E., iron rails, life of 1 Hatt, W. K.: impact tests 292 tests on strength of timber 157, 169 tie plates 169 Hawaiian Ohia ties: amount purchased in the United States.. . 156 cost of 156 Head: bull, rail, examples of 19 specifications for 484 double, rail (see Bull head rail), rail: crushed (see Crushed head). effect of casting on 390 flat spot in wheel on 56 fatigue of metal in 203, 284 flow of metal in (see Flow of metal) . principles governing design 16 392, 394, 424, 431 Head rail: size of grain in split (see Split head), strength of, experiments on, at Mary- land Steel Company . . . steel from stress at point of contact with wheel . thermal cracks in transverse fissures in unsound metal in 205 203 sweep Heath, Josiah, early experiments with open hearth furnace Heating curve of steel Hecla Belt Line, concrete ties on Hemlock : physical properties of 166, ties, amount purchased in the United States 154, cost of 154, Hennebique, concrete tie Heroult electric furnace Hickey tie Hickory, physical properties of High T-rails: examples of specifications for Hill fastening on Carnegie steel tie Hiroi, I., web stresses Hocking Valley Railroad, size and spac- ing of ties Hoffman, elastic curve of tie Holley, A. L.: bottom casting used by design of Bessemer plant Honigsberg, O., measurement of forces be- tween wheel and rail Hook plates: examples of 127, 128, 129, 130, German experiments with Hook spike (see Spikes). Horizontal pressure of wheel on rail Hot beds shortness in steel work, effect of, on steel Howard, Coes and, experiments on rocking of engine Howard, James E. : examination of rolling at different stages . . experiments on repeated stress flow of metal in head of rail report on Great Northern wreck Lehigh Valley wreck Howe, H. M.: blowholes 259 445 445 330 428 420 278 325 203 540 Howe, H. M.: effect of copper on steel 332 nickel on steel 335 rolling on structure of steel 427 phosphorus in rail steel 465 piping and segregation 401, 404, 409 network and ferrite grains in steel 427 on nickel steel 335 relation between carbon content and strength of steel 329 Howe, M. A., bearing power of earth 313 Howorth, Captain, effect of slag in steel. . . . 391 Hulett ore unloader 354 Humfrey, J. C. W., experiments on repeated stress 274 Hundred per cent joint 264 Hunnewell plantation 109 Hunt, R. W.: effect of copper on steel 332 manufacture of early rails 324 piping of ingots 399 Hunt, R. W., and Company: American rolling mill practice 438, 444 branding of rails 447 method of inspection at mills 464 shrinkage allowed at American rail mills . . 444 teeming practice at American rail mills. . . 399 Hydrogen, evolution of, in cooling steel 401 Hyper-eutectoid steel 427 Hypo-eutectoid steel 427 Illingworth's process for compression of ingot 411,415 Illinois Steel Company (see Gary; South Works). Impact : bibliography of 288 discussion of, as applied to tests 293 effect of, on strength of pine ties 158 track 68 in bridge specifications 210 increase in wheel load due to 68 tests by Professor Goss on engine drivers 62 drop (see Drop test). on bridges 64 Incision, angle of, in rolling 457 Indentation test 300 India, length of rails used in 267 Indiana Engineering Society, flat spots on car wheels 55 Indiana Railroad Commission (see Railroad Commission of Indiana). Indiana Steel Company (see Gary). Indirect pressure in rolling 456 Inertia: moment of (see Moment of inertia). of roadbed, effect of, on bearing power 189, 318 Inertia: of track, effect of, on impact of wheel. ... 68 rail stresses 318 Ingot : bled, specifications for 473 blowholes in 401 casting 395 discard from 416 fluid compression of 410, 415 form for reporting rails which failed from different parts of, American Railway Engineering Association 516 lettering rails from 416 piping of 399 reduction necessary for different parts of. . 420 segregation of 404 size of, at American mills 438 stripper 397 Inspection : form for, American Railway Engineering Association 504 specifications for, in rails (see also Specifi- cation in question) 464 tendency toward greater, at mill 464 Institution of Civil Engineers: Bell, on deflection tff rails in track 190 Kirkaldy, on wear of rails 205 Sandberg, manufacture and wear of rails . . 1 Williams, maintenance of permanent way. 1 Intergranular weakness in steel 272 International Association for Testing Materials : drop testing machine 291 hardness tests 300 impact tests 292 slag in steel 393 thermoelectric measurements of stress .... 311 International Railway Congress: Dudley, on tonnage of rails and wheels. . . . 202 report on contact area between wheel and rail 195 effect of speed on the track 28 electric traction 74 joints 266 length of rail 266 use of screw spikes 150 Interstate Commerce Commission, report on Lehigh Valley Railroad wreck 203 Interurban cars 87, 88 Interurban railways (see Electric railway). Interurban Rapid Transit, concrete ties on.. 104 Ireland (see English). Iron: carbon diagram 427 cast, manufacture of 357 content in ore 344, 363, 36^ 541 Iron: conversion of, into steel 366 cooling curve of 426 cupola 365 effect of repeated stress on 274, 277 extraction of, from its ore 344 ore (see Ore). oxide, blowholes caused by 389 pig, manufacture of 357 rails, life of, in American railroads 4 United Kingdom 2 on North Eastern Railway 1, 2 price of 2, 325 wear of 1 structure of 270 Zores 173 Iron and Steel Institute: effect of slag in rail steel 391 experiments on influence of arsenic on steel 331 on influence of copper on steel 331 on repeated stress 276 Iron rails (see Iron). Jaggar test for hardness 303 Jeans, J. S.: early steel rails 2 origin of pneumatic process of making steel 367 Job, Robert: cells per square inch in rail steel 424 unsoundness of head of rail 391 John Brown and Company (see Brown, John, and Company). Johnson, L. E., ties, supply of 106 Johnson, Professor: compression modulus as affected by sur- face of contact 193 experiments on contact between wheel and rail 194 Johnson, Thomas H. : distribution of pressure through ballast . . 185 drop testing machine, tests on 291 Joints (see also Joint in question) : American Railway Engineering Associa- tion tests on 264 bibliography of recent literature on 268 chemical composition 264, 266 economic distribution of metal in 263 effect of, on rail stresses 259 fishing angle, determined by Chanute .... 6 for bull head rail 19 friction of 260 on American railways 264 on English and Scotch railway.-, arrange- ment of 19 Joints : on French railways, arrangement of 144 on German railways, arrangement of 144 size of 218 oil tempered 266 shear in 262 Watertown Arsenal tests on 260, 264 welded 267 Jones, Capt. Wm. R., development of mixer by 365 Jones and Laughlin Steel Company: duplex process employed at 388 tilting open hearth furnaces at 377 Jouraff sky, effect of cold on rails 285 Kansas City, Mexico and Orient Railway: Mogul type engine 34 size and spacing of ties 121 Keep test for hardness 303 Kellogg, R. S., timber supply of the Unite 1 States 106 Kelly, William, pneumatic process of mak- ing steel 367 Kennedy-Morrison process 435 Kennedy stove 360 Key, oak for double-headed rail 19 Kimbal tie 99, 105 Kingdom of Saxony State Railways: arrangement of joints on 144 data on track 218 rail and tie plate 129 spikes used on 144, 145 weight of rail on 19, 144 Kingdom of Wiirttemberg State Railways: arrangement of joints on 144 rail and tie plate 127 screw spikes on 144, 145 weight of rail on 19 Kirkaldy, wear of rails 205 Kneedler concrete tie 104 Krupp mills, fluid compression of ingot 415 Lackawanna Steel Company: rail mill 438,444 shrinkage allowed at 444 strength of steel from 309 teeming practice 399 titanium steel rails ' 340 Ladle, casting 389 Lake Erie and Western Railroad: concrete ties on 105 size and spacing of ties 121 Lake Shore and Michigan Southern Railway: composition and metal ties on.. . . 96, 104. 105 concrete ties on 104, 105 prairie type engine 33 542 Lake Shore and Michigan Southern Railway : size and spacing of ties 121 speed of trains 24, 25, 26, 27, 28 tests on chilled car wheels 57 Lakeside and Marblehead Railroad, concrete ties on 105 Lake States, lumber production of 108 Lake Superior: ore industry 349 ores, iron content 344 Lakhovsky screw spike 148 Lancashire and Yorkshire Railway, rail fastenings on 146, 147 Lanza, Gaetano: driving wheel spring tests 49 effect of suddenly applied load 54 Larch: force required to pull spike from 140 physical properties of 140, 166 Leading truck: allowable weights on 321 on freight and passenger engines 32, 33, 34, 72 Lebanon iron used at Maryland Steel Company 374 Lebasteur, impact tests 293 Lehigh Valley Railroad: size and spacing of ties 121 speeds of trains on 25 wreck caused by broken rail 203 Length of rails: report on, International Railway Con- gress 266 specifications for (see also Specification in question) 474 Lettering rails from different parts of ingot . . 416 Limestone used in blast furnace 365 Loading: axle (see Axle loads). dynamic, for different types of cars .... 85, 89 for different types of electric engines 78 for different types of steam engines 72, 73 E-60 211 maximum axle, allowable on rail 319 rail, for different classes of track 319 specifications for, rail 478 weights of rail for different conditions of 322 Loblolly pine (see also Pine) : forse required to pull spike from 139 physical properties of 158, 164, 166, 170 tie, decay in spike hole 139 wear of, under tie plate 123 Locomotives: allowable axle loads of 322 Locomotives: axle loads of (see Axle loads). classification of 9 counterbalance pressure (see Counter- balance). decapod 29, 31 development in, at Baldwin Locomotive Works 30 on Pennsylvania Rail- road 30 draw bar pull, effect on track 71 driving wheels (see Driving wheels) . dynamic augment of wheel pressure (see Dynamic) . effect of rocking of, on track 49, 71 on track of badly balanced 39 electric (see Electric locomotives), freight, development of, on Pennsylvania Railroad 30 examples of 33, 34, 72 passenger, development of, on Pennsyl- vania Railroad 30 examples of 32, 33, 72 Pennsylvania Railroad tests on steam and electric 74, 259 rail stresses caused by (see Stresses). speed of 21, 23, 29 springs (see Springs). steam, best speeds of 27 dimensions of 32, 33, 34, 72 weights of different types, 29, 32, 33, 34, 72 strength of track required for 322 tires (see Tires). types of (see also Type in question) : American 21 articulated 34, 72 Atlantic 21, 29, 32 consolidation 29, 34 eight-wheel 21, 29 Mallet 21 Mikado 31 Mogul 34,72 Pacific 21,29,32 prairie 33, 72 ten-wheel 33, 72 typical dynamic wheel loads 72, 73 weight of rail required for 322 weights of 29, 32, 33, 34, 72 wheels (see Wheel) . Locust, plantations of, for tie timber. . . 109, 111 Lodgepole pine ties : amount purchased in the United States 154, 156 cost of 154, 156 London and North Western Railway: early steel rails on 3 543 London and North Western Railway: permanent way 19 rail fastenings on 19, 147 screw spikes on 19, 146, 147 section of rail 19 speed of trains 24, 26, 28 London, Brighton and South Coast Railway, early steel rails on 3 Long Island Railroad, size and spacing of ties 121 Longleaf pine (see also Pine), physical properties of.. 164, 166, 167, 168, 169, 170 Losses in drop testing machine 293 Louisville and Nashville Railroad : plantations for tie timber Ill size and spacing of ties 121 Love, C. E.: analysis of Government track experi- ments 240 relation between depression and pressure on tie 192 Ludwick, hardness tests 300 MacPherson, D., long ties used on muskeg swamp 188 Magnetic crane for loading rails 446 testing of rails 303 Main driver (sec Driving wheels). Main rod: angularity of, effect of inertia of track on 'stresses produced by 69 effect of angularity of, calculation of 35 pressure on rail caused by angularity of . . 35 Maine Central Railroad, size and spacing of ties 121 Mallet type engine (see also Articulated engine) : description of 21 dimensions of • • 34, 72 draw bar pull of 22 speeds of 22 weights of 34, 72 Maltitz, E. von: blowholes 389, 391, 404 effect of recarbonizing 391 Manganese: content in rails: of Bessemer steel 11, 253, 310 of open hearth steel 310 specifications for (see also Specification in question) 328, 342, 466 effect of, in casting 402 steel 330 on blowholes 402 ferro 330, 374, 380 in iron ore 363, 364 Manganese: segregation of 409 specifications for, in rails (see also Specifi- cations in question) 328, 342, 466 steel 333, 336, 341 rails, production of 341 use of, on steam railways 333 street railways 339 sulphide in steel 390 Manufacture: bibliography of literature on steel (see Preface). casting the ingot 395 conversion of iron into steel 366 difficulty in heavy A.S.C.E. rail 7, 14 early process of rail 324 extraction of the iron from its ore 344 influence of detail of 324 of car wheels 57 of iron rails 1,2 rolling 420 specifications for (see also Specifica- tions) 473 Manufacturers (see Association of American Steel Manufacturers): Steel, of America (see Association of Ameri- can Steel Manufacturers). Maple ties: amount purchased in the United States ... 156 cost of 159 Marston, A., experiments on steel rollers on steel plates 194 Martens, Professor, impact tests 292 Martin, S. S., drop tests 288 Maryland Steel Company: Bessemer converters at 370, 374 blast furnaces at 363 cold straightening press at 446 duplex process employed at 388 experiments on rolling rails 430 iron cupola at 365 Mayari ore used at 335 rolhng mill practice 438, 444 shrinkage allowed at 444 teeming practice 399 tests on strength of rail head 252 titanium rail steel 340 Massachusetts Institute of Technology: Coes and Howard's thesis on driving wheel springs 49 congress of technology 30 Master Car Builders' Association: limiting length of flat spot in car wheels . . 56 standard tire 7 wheel in relation to design of rail 6, 17 544 Master Mechanics Association (see American Railway Master Mechanics Associa- tion). Mayari ore 335 McGill University, indentation tests 300 McKee tie plate: examples of 122 tests on 122 McKeen motor car 86 McKenna process for rerolling rails 459 Mechanical work, influence of, on steel 427 Mellor, J. W.: changes during cooling of metals 425 crystalline structure of metals 270 Menard, friction of joints 261 Mesquite ties: amount purchased in the United States ... 156 cost of 156 Metal ties (see also Tie in question) 90 Metcalf, William, phosphorus in rail steel . . . 465 Mexican Railway steel tie 96 Michel, Jules: holding power of spikes 140 influence of form of thread on holding power of screw spikes 148 Michigan Central Railroad: chemical composition of rails 328 concrete ties on 105 consolidation type engine 34 continuous rail on 268 80-lb. rails used on, in 1893 7 electric locomotives in Detroit River tunnel 80 plantations for tie timber 112 size and spacing of ties 121 speeds of trains on 24, 26 Middle driver (see Driving wheels). Midland Railway: permanent way 19 rail fastenings on 19, 146, 147 section of rail 19 speed of trains 28 Mikado type engine: classification of 29 description of 31 Mill: American, practice 399, 438, 444 blooming 436, 438 reversing cogging 437 rolling (see Rolling). three-high 437 Minneapolis and St. Louis Railroad, size and spacing of ties 121 Minnesota, iron ore mines in 346, 347 Missouri and North Arkansas Railroad, size and spacing of ties 121 Missouri, Kansas and Texas Railway System, size and spacing of ties 121 Missouri, Pacific Railway Systems, size and spacing of ties 121 Mixer: development of 365 metal used in open hearth heat, analysis of 380 Mobile and Ohio Railroad, size and spacing of ties 121 Mockernut hickory, physical properties of. . . 164 Modulus: of compression (see Compression). of elasticity of steel 225, 241 wood 158, 166, 168 of rupture (see also Ultimate strength). of steel 306 wood , . 158, 164, 166, 168 section, of different rails (see also Rail in question) 319 Mogul type engine: allowable axle loads 322 classification of 29 dimensions of 34, 72 effect of excess balance and angularity of main rod 43, 70 rail stresses caused by 222, 237 speeds of 70 strength of track required for 322 typical dynamic wheel loads 73 U. S. Government experiments with 222 weight of rail required for 322 weights of 34, 72 Moisture (see Water). Moment, bending (see Bending moment). Moment of inertia: load diagram for rails having different . . . 319 of different rails (see also Rail in question). 319 of rails and joints on German railways. . . . 218 Motor cars 85, 86 Munshet, improvement in making steel 367 Nail spike (see Spikes). National Conservation Commission, report on ores 345 New England States, lumber production of 108 New Jersey Steel and Iron Company, first open hearth furnace in America 375 New York Central and Hudson River Rail- road: concrete ties on . . 104 80-lb. rails used on, in 1893 7 electric locomotives 79 Pacific type engine 32 rail section 10 New York Central and Hudson River Rail- road : rail failures 10 size and spacing of ties 121 speed of trains 23, 24, 25, 26, 28 stremmatograph tests 237 ten- wheel type engine 33 wear of rails on 328 New York Central Lines: specifications for rail 478 speed of trains 23 titanium steel rails 341 New York, Chicago and St. Louis Railroad, size and spacing of ties 121 New York, New Haven and Hartford Rail- road: electric locomotives 74, 80 size and spacing of ties 121 speed of trains 28 New York, Ontario and Western Railway, size and spacing of ties 121 New York Railroad Club, annealed rails .... 208 Nickel, chrome, steel rails: production of 341 use of 333 Nickel, effect of, in steel 334 Nickel Plate, concrete ties on 105 Nickel steel rails : production of 341 use of 333 Nicolaieff, ore used at Maryland Steel Company 363 Nicolas Railway (of Russia), early steel rails on 3 Nicolia, effect of cold on rails 285 Nisbet, productivity of woodlands 114 Nitrogen: effect of, in steel 287, 341 on ductility of rail steel 287 titanium on, in steel 287, 341 evolution of, in cooling steel 401 Norfolk and Western Railway: chemical composition of rails 328 manganese rails on 333 plantations for tie timber 112 size and spacing of ties 121 Norfolk Southern Railroad, size and spacing of ties 121 North Austrian Railways, experiments on rails rolled for 450 North British Railway, rail fastenings on, 146, 147 North Chicago Rolling Mill, early steel rails 3 North Eastern Railway (of England) : iron rails on 1 rail fastenings on 147 speed of trains 28 Northern Pacific Railway: management of timber lands on 113 size and spacing of ties 121 Northern Railway (of Austria), early steel rails on 3 Northern Railway (of France) : arrangement of joints on 144 early screw spikes used on 141 screw spikes on 143, 144 speed of trains 24 Northern Railway (of Spain), concrete ties on 104, 105 North Western Pacific Railroad Company, size and spacing of ties 121 Norway pine, physical properties of . . . . 166, 168 Nutmeg hickory, physical properties of 164 Oak: ferrule for spike 19 force required to pull spike from 139, 140 key, for double-headed rail 19 permissible load under tie plate 171 physical properties of 164, 168, 170 plantations of, for tie timber Ill ties, amount purchased in the United States 154, 156 annual charge of 115 cost of 154, 156 on French Eastern Railway 117 Oklahoma Railway Company, car used on. . . 88 Old Colony and Newport Railway, early steel rails on 2 Open hearth: comparison of, with Bessemer process. . . . 380 description of process 375, 378 early experiments with 375 steel, analysis of 310 rails, branding 447 ductility of 286 hardness determined by sclero- scope 299 production of 382 specifications for, 342, 463, 478, 491 strength of 306 Talbot continuous process 375 tilting furnace 375 Ore: analyses of 363, 364 docks 351, 357 extraction of iron from 344 handling of 351, 357 iron content in 344, 363, 364 Lake Superior mining 351 Mayari 335 roasting 344 supply of, low phosphorus 374, 381 Ore: transportation of , 349 unloader 352 used in blast furnace 360, 363, 364 open-hearth furnace 378, 380 vessels 349 Oregon Electric Railway Company, cars used on 87 Oregon Railroad and Navigation Company, ten- wheel type engine 33 Oregon Short Line Railroad, Atlantic type engine 32 Orleans Railway: arrangement of joints on 144 screw spikes on 144 Osmond, transition points in steel 426 Overcup oak, physical properties of 164 Oxygen, effect of, in steel 401, 404 Pacific States, lumber production of 108 Pacific type engine: allowable axle loads 322 classification of 29 description of 21 dimensions of 32, 72 effect flf excess balance and angularity of main rod 41, 70 pressure rounding curve 259 rail stresses caused by 215 speeds of 21, 26, 70 strength of track required for 322 typical dynamic wheel loads 72 weight of rail required for 322 weights of 31, 32, 72 Paris, Lyons and Mediterranean Railway: arrangement of joints 144 axle loads used on 19 early steel rails on 3 experiments on ties 172 screw spikes 143, 144 section of rail 19 m, South Works 442 r cars (see Cars). locomotives (see Locomotives). Passes: cogging, Puppe's tests 448, 450 number in rolling rail 438 Pay-as-you-enter cars 88 Pearlite 427 Pecan hickory, physical properties of 164 Pennsylvania Lines: concrete ties on 97, 102, 104, 105 continuous rail on 267 nickel steel rails on 333 Pacific type engine 32 plantations for tie timber 112 Pennsylvania Lines: prairie type engine 33 size and spacing of ties 121 special steel rail on 333 speed of trains 25, 26 steel ties on 94 Pennsylvania Lines West of Pittsburgh (see Pennsylvania Lines). Pennsylvania Railroad: chemical composition of early rails 328 rails 328, 342 committee on rail section 18 continuous rail 267 development in locomotives since 1850 ... 31 early experiments on wear of rails 326 steel rails used on 4 electric locomotive 74, 76, 79 horizontal pressure on rail exerted by engine wheel 259 joint 264 plantations for tie timber Ill prairie type engine -. . 33 rail section 10, 18 deflection in drop test 291 failures of n "P. S." section (see Pennsylvania Stand- ard section) . size and spacing of ties 121 specifications for rail 342, 463 speeds of trains 24, 26, 27, 28 steam and electric locomotives, tests on 74, 257 steel ties on 96 tests on ballast 184 track experiments on, by TJ. S. Govern- ment 225 weight of sleeping cars 82 Pennsylvania Standard ("P. S.") section: deflection in drop test 291 design of 18, 460 failures of 10 Pennsylvania Steel Company: bottom casting at 410 early steel rails 4 machine for testing rail wear 303 rail mill 438, 444 shrinkage allowed at 444 use of iron with high copper 332 Percival concrete tie 101, 105 Pere Marquette Railroad, concrete ties on, 104, 105 Permanent Way: of English railways 19 maintenance of 1 "Pewter" rails 12 Philadelphia and Reading Railway: 90-lb. rails used on, in 1893 7 547 Philadelphia and Reading Railway: performance of fine structure rails on 424 size and spacing of ties 121 speed of trains 24, 28 tests on annealed rails 208 Philadelphia Rapid Transit, concrete ties on 104 Philadelphia, Wilmington and Baltimore Railway, early steel rails on 2, 4 Phosphorus : content in rails of Bessemer steel.. 11, 253, 310 open hearth steel 310 effect of, in steel 329 on ductility of rail steel 286 in iron ore . . segregation of 408 specifications for, in rails (see also Speci- fications) 328, 342, 466 supply of ores low in 374, 381 Physical properties: of rails, form for reporting, American Railway Engineering Association. . . . 503 of special steels (see Special steels). of steel (see Steel). of wood, treated 158 untreated 158, 164, 166, 168 Pig iron, manufacture of 357 Pignut hickory, physical properties of 164 Pine: effect of moisture on strength of 169 force required to pull spike from 139, 152 permissible load under tie plate 171 physical properties of, 158, 164, 166, 167, 168, 169, 170 ties: amount purchased in the United States 154, 156 annual charge of 115 cost of 154, 156 effect of preservative treatment on strength of 158 tests on treated 158 wear of, under tie plate 123 Pipes in ingots: bibliography of recent literature on 418 cause of 399 effect of fluid compression on 410, 415 rapid charging into heating fur- nace 400 titanium on 405 Howe's experiments on 409, 411 tests to detect 464, 469 Pittsburgh and Lake Erie Railroad : concrete ties on 101, 105 tie plate 122 Pittsburgh, Cincinnati, Chicago and St. Louis Railway (see also Pennsylvania Lines) : chemical composition of early steel rails on 326 speed of trains 24 Pittsburgh, Fort Wayne and Chicago Rail- way (see also Pennsylvania Lines), speed of trains 24 Pittsburgh Railway Club, Fowler's experi- ments on contact of wheels with rails 195 Plantations for growth of tie timber 109, 111 Pneumatic method of making steel (see Bessemer) . Pole tie 119 Poplar: force required to pull spike from 140 plantations of, for tie timber Ill tie plates of, on French Eastern Railway . . 132 Post oak, physical properties of 164 Poutzen, friction of joints 261 Prairie type engine: classification of 29 dimensions of 33, 72 speeds of 70 typical dynamic wheel loads 72 weights of 33, 72 Prepayment cars 88 Preservation, tie (see Treated ties). Pressure: allowable on subgrade, amount of. 187, 189, 317 calculation of 313 under tie plate 171 casting ingots under 410, 415 direct, in rolling 456 distribution of, to subgrade 180, 185 effect of steam, on treated ties 158, 162 indirect, in rolling 456 of wheel on rail: at point of contact 193 caused by drawbar pull 71 flat spot on wheel 54 excess pressure of counter- balance and angularity of main rod 35, 70 impact 68 irregularities in the track. . 45, 71 rocking of engine 49, 71 velocity of load 70 weight of tender 71 dynamic, of cars 85 electric engines 78 steam engines 71, 72 effect of change in grade on 45 inertia of track on 69 548 Pressure: horizontal component of, on curves .... 259 static, cars 85 electric locomotives 77, 79, 80 steam locomotives 29 working, of steam locomotives, 37, 40, 41, 42, 43, 44 Production: lumber, in the United States 108 rail, in the United States 382 ties, in the United States 154, 156 Profile of rail 46, 47 Prussian Government Railroads: experiments on tie plates 133 screw spikes used on 144, 145 tests on strength of rails 302 Prussian Hessian Railways, data on track. . . 218 Prussian Railway Department, hardness tests 302 Prussian State Railways: arrangement of joints on 144 rail and tie plate 131 speed of trains 27, 29 spikes used on 144, 145 ties with screw dowels 151 weight of rail on 131, 144 "P. S." rail section (see Pennsylvania Standard section). Puppe, experiments on rail rolling 447 Purdue University, tests on tie plates 169 Pyrometers 434, 476 Queen and Crescent, chemical composition of rails 328 Rail: advance wave determinations of 221 annealed 208 base (see Base rail). bearing of, on tie 122 bending, affected by flow of metal in head 204 bending moment (see Bending moment). branding 446 broken (see Broken rails) . base (see Broken base). by defective equipment 57 bull head 19,484 camber in 444, 477, 482 chemical composition (see Chemical com- position). continuous 267 corrugations in . . 209 creeping of 153 crushed head (see Crushed head). Rail: defective (see Defective rails). design of (see also Section), investigation of, by Ashbel Welsh 5 design of (see also Section), investigation of, by Chanute 6 design of (see also Section), principles governing 16 double head 19, 484 ductility of steel (see Ductility). dynamic load for different classes of track . 319 effect of cold on 284 repeated stress on 284 elastic curve of 241, 242 electric steel 383 exhausted metal in 204, 284 failures, chart of, Harriman Lines 524 reported by American Railway Engineering Association .... 10 typical, photographs of 11 fastening of, to tie 138 fastenings (see Joints), flange (see Base, rail). flat bottom 19, 488 flow of metal in head of (see Flow of metal). gagging, or cold straightening 446 girder (see Street railway). grooved (see Street railway). hardness tests on (see Hardness tests). head (see Head, rail). horizontal pressure of wheel on curves. . . . 259 iron 1,324 joint (see Joints). length of 267, 474, 485, 489, 492 lettering from different parts of ingot . . . 416 load for different classes of track 317, 322 manufacture (see Manufacture), manufacturers (see Association of Ameri- can Steel Manufacturers). mill (see Rolling), moment of inertia of standard (see also Rail in question) 319 performance of fine structure 424 heavy sections 7, 10 prices of 325 production 382 profile of 46, 47 records (see Reports and records), reports (see Reports and records). rerolled 459 road (see Road in question). roaring 209 rolling (see Rolling). section modulus of standard (see also Rail in question) 319 Rail: sections (see Section), shear in (see Shear), special (see Special rails), specifications (see Specifications). split head 10, 390 web 10 stamping 446 steel, first made in America 3 used in America 2 foreign countries ....... 3 John Brown and Company .... 4, 5, 326 special (see Special rails). straightening 446 strains produced in, by straightening 445 street railway (see Street railway). strength of 270, 310 stresses in (see Stresses) . supports of 90 T- (see T-rail). temperature, effect of on, cold 284 finishing (see Fin- ishing) . tests of, hardness (see also Hardness tests) . 298 impact (see Drop test). tests on, by U. S. Government 218 stremmatograph 71, 212, 236 tramway (see Street railway). transverse fissures in head 203 way (see Road in question), wear (see Wear), web (see Web, rail). weights of, for different loading 310, 322 on English railways 19 French railways. ... 18, 19, 144 German railways . . 19, 125, 144 specifications for (see also Speci- fication in question). Railroad (see Road in question). Railroad Commission of Indiana: Buffington, on quality of rail 325 Cushing, on discard of ingot 417 Dudley, on wear of rails 328 Railway (see Road in question). Rainfall on ballast in Pennsylvania Railroad tests 184 Rasch, thermoelectric measurements of stress 311 Rear driver (see Driving wheels). Recalescence 425 Recarbonizer (see also Ferromanganese) .... 366 Recarbonizing: effect of, on steel 389 in Bessemer converter 374 in casting ladle 391 in electric furnace 385 in open-hearth furnace 380 Reciprocating machine, tests on rail head with 256 parts on locomotives (see also Counterbalance) 32, 35 Records (see Reports and records). Red cedar, physical properties of 168 Red gum : crushing strength of 170 plantations of, for tie timber 112 Red oak (see also Oak): force required to pull spike from 139 physical properties of 139, 164, 170 plantations of, for tie timber Ill tie, annual charge of 115 Red pine, physical properties of 164 Red shortness in steel 330, 332 Red spruce, physical properties of 166 Reduction necessary from ingot to rail 420 Reduction of area: effect of chemical composition on (see Element in question). size of grain on 424 in rolling, Puppe's tests 448 of electric steel 386 of rail steel 306 Redwood: physical properties of 166, 168 ties, amount purchased in the United States 154, 156 cost of 154, 156 Reheating furnace 396 Repeated stress (see Stresses). Reports and records: by American Railway Engineering As- sociation : compilation of results for study 512 from Division officers 506 inspection and shipment at mill 501 laboratory examination of special rails.. 511 progressive wear of special rail 517 chart of rail failures, Harriman Lines 524 form for continuous record shown graphically 523 Republic Iron and Steel Company, blast furnace 355, 356 Rerolled rails 459 Resal, friction of joints 261 Reversing cogging mill 437 Reynolds and Smith, experiments on re- peated stress 278, 282 Rhymney Railway (of England), early steel rails on 3 Richards, R. H.: influence of copper on steel 332 roasting ores 344 Riegler tie 102 Riese, elastic curve of tie 172 Roadbed (see Subgrade). Roaring rails 209 Roasting ore 344 Rock (see Stone). Rock Island (see Chicago, Rock Island and Pacific Railway). Rocking of engine: Coes and Howard's experiments on 49 effect of inertia of track on stresses pro- duced by 69 on wheel pressure 49, 71 Roechling Rodenhauser electric furnace .... 385 Rogers, F., experiments on repeated stress. . 282 Rolling: American practice 438 direct .pressure in 456 early rails 324, 434 effect of, on grain size 424, 427 experiments at Maryland Steel Company . 430 Watertown Arsenal by Howard 420 by Puppe 447 heavy A.S.C.E. sections 7, 435 indirect pressure in 456 Kennedy-Morrison process 435 mill at Algoma Steel Company 437, 438 Gary 437,438 South Works 438, 443, 444 practice at American 438, 444 power required for 458 reduction at each pass 436, 438 structural changes during 420 tests on head of rail 205, 256 work done in, Puppe's tests 448 worn rails, McKenna process 459 Rolls, design of 457 Roozeboom, H. W. B., carbon-iron diagram . 427 Rosenhain, W. : experiments on repeated stress 273 slag enclosures in steel 393 Roughing pass 437, 438 Rudeloff, experiments on nickel steel 334 Russia: early steel rails 3 effect of cold on rails in 285 Rutland Railroad, size and spacing of ties. . . 121 San Antonio and Arkansas Pass Railway: plantations of tie timber 112 size and spacing of ties 121 Sand: angle of friction of 314 weight of 316 Sandberg, C. P. : drop testing machine 288 Sandberg, C. P.: experiments on effect of cold on rails . . . 284 manufacture and wear of rails 1 Santa Fe (see Atchison, Topeka and Santa Fe Railway). Santa Fe, Prescott and Phcenix Railway, size and spacing of ties 121 Sarada tie 102, 104 Sarnia tunnel, electric locomotive 80 Sauveur: rail structure 429 relation between size of grain and physi- cal properties of steel 424 Saw: hot. rail. 445 445 runs at American mills 445 Saxony State Railways (see Kingdom of Saxony State Railways). Schubert : depression of tie in ballast 190 experiments on ballast 180 Schwald, elastic curve of tie 172 Sclerometer 302 302 Scratch test for hardness ' Screw spikes (see Spikes). Seaboard Air Line Railway, size and spacing of ties 121 Seasoning, effect of, on strength of wood .... 168 Seating capacity of electric cars 87, 88 Section, rail (see also Section in question) : American 10, 14, 18, 19, 460 American Electric Railway Association 19 American Railway Association 14 American Society of Civil Engineers 6 British standard 19 bullhead 19 comparison of failures of different sections 10 designed by Ashbel Welsh 5 Chanute 6 Dudley 11 early 1 English 19 flat bottom 19 French 19 German 19, 125 girder 19 grooved 19 high tee 19 New York Central and Hudson River Railroad 11 Pennsylvania Railroad 11 Pennsylvania standard 18 14, 460 551 Section, rail: principles governing design of 16 specifications for (see also Specification in question) 476 street railway (see Street railway). tramway 19 Vignole 18 Section moduli of different rails (see also Rail in question) 319 Seeley concrete tie 104 Segregation: bibliography of recent literature on 418 cause of 404 effect of fluid compression on 410, 416 titanium on 406 Howe's experiments on 409, 411 Selby, O. E., stresses in the rail 210 Series "A," American Railway Association. . 14 "B," American Railway Association. . 14 Shagbark hickory, physical properties of ... . 164 Shear: calculation of, for 100-lb. rail 239 distribution of, in 100-lb. rail 250 in rail and joint 262 calculation of 239 Love's diagram of 241 intensity of, at any point 250 specifications for (see also Specification in question) 473 Ship, used on Great Lakes for transporting iron ore 349 Shipment: form for reporting, American Railway Engineering Association 505 of iron ore (see Transportation). Shock (see Impact). Shortleaf pine (see also Pine) : physical properties of 164, 166, 168, 170 tie cut through spike holes 138 Shrinkage: allowed at American mills 444 English mills 435 specifications for (see also Specification in question) 475 Shwedler, elastic curve of tie 172 early open hearth furnace 375 furnace 375 reheating furnace 437 Sierra Morena ore, used at Maryland Steel Company 363 Silica, in iron ore 363, 364 Silicon: content in rails of Bessemer steel. 11, 253, 310 open hearth steel 310 effect of, in casting 401, 402 Silicon, effect of, in steel 329 on blowholes 402 segregation of 409 specifications for, in rails (see also Specifi- cation in question) 328, 342, 466 Six-wheel engine: classification of 29 coupled, classification of 29 Slade, F. J., first open hearth furnace in America 375 Slag: in steel 391 unsound metal caused by 391 Sleeper (see Ties). Sleeping car 84 Slip: bands caused by repeating stress 274 coefficient of, locomotive drivers 198, 199 means of determining, in earth 313 Smelting, iron ore 344, 357 Smith, H. E., tests on chilled car wheels. . . 57 Smith and Reynolds, experiments on re- peated stress 278, 282 Snyder steel tie 96 Soaking pits 396 Soils, supporting power 313 Solid solution of iron 427 South Africa, length of rails used in 267 South America, length of rails used in 267 South Works, Illinois Steel Company: electric furnace at 383 experiments with new section of rail 462 Forsyth's transferring ladle 390 pass diagram 442 rail mill 438,442 shrinkage allowed at 444 teeming practice 399 Southern Pacific Company: Mogul type engine 34 plantations of tie timber 112 size and spacing of ties 121 speed of trains 26, 28 timber lands of 113 Southern pine (see Pine). Southern Railway: Atlantic type engine 32 chemical composition of early rails on ... . 326 plantations for tie timber 112 size and spacing of ties 121 Southern Railway (of France): arrangement of joints on 144 screw spikes on 144 Southern States: lumber production of 108 ores in 381 552 Spangenberg's experiments on repeated stress 277 Spanish oak, physical properties of 164 Special rails (see also Special steels) : form for reporting laboratory examina- tion of 511 form for reporting wear of 517 Special steels: chrome nickel 333, 341 chromium 333, 341 cupro-nickel 332 electric 341, 383 manganese 333, 336, 341 nickel 333, 334, 341 production of 341 titanium (see Titanium). Specific gravity: of manganese sulphide 390 of steel 390 of wood 158, 163 Specifications: axle loads given in bridge 211 for drop testing machine 290 Specifications, rail: American, comparison of: bled ingots 473 branding 477 chemical composition 342, 465 discard 473 drilling 477 drop test 470 finishing 477 finishing temperature 475 inspection 464 length 474 loading 478 Nos. 1 and 2 rails 472 physical requirements 467 process of manufacture 473 quality of manufacture 473 section 476 473 475 weight 476 bibliography of 494 British standard bull head railway rails.. . 484 flat bottom railway rails. . 488 chemical composition (see also Specifica- tion in question) 342, 465 for street railways, American Society for Testing Materials 491 of American Railway Engineering Asso- ciation 463 of American Society for Testing Materials. 491 of Association of American Steel Manu- facturers 342, 463 Specifications, rail: of Harriman Lines 463 of New York Central Lines 478 of Pennsylvania Railroad System 342, 463 Speed: effect on bridges due to velocity of load . . 69 counterbalance pressure 35 depression of tie 190 track 29, 189, 191 due to velocity of load 70 Prussian State Railways 29 fast runs in last three decades 23 in rolling mills, Puppe's tests 458 of electric locomotives 27, 29, 79, 80 of modern trains 21, 23 Spiegle (see also Ferromanganese) 374 Spiegle-eisen (see also Ferromanganese) 374 Spikes: common or nail 140 used on English railways. . . 146, 147 German railways . . . 144, 145 comparative cost of screw and common. . . 142 effect of treatment on holding force of . . . . 159 holding power of 139 hook 140 screw 140, 142 cost of equipping track with 142 examples of English 19, 146 French.. 143,144 German 144, 145 influence of design of thread on holding power 148 machine for preparing ties for 142 on the Atchison, Topeka and Santa Fe Railway 141 use of dowel with 142, 150 Splice bars (see Joints). Split head: classification of, American Railway En- gineering Association 10 effect of casting on 390 photographs of typical failures 11 rail failures, six months ending April 30, 1909 10 Split web : classification of, American Railway En- gineering Association 10 photographs of typical failures 11 rail failures, six months ending April 30, 1909 10 Spokane and Inland Railroad, electric locomotives 80 Springs, locomotive driving: Coes and Howard's experiments on 49 dimensions of 48 effect of inertia of track on 69 553 Springs, locomotive driving: effect of suddenly applied load 54 rocking of engine on 49 weight borne by, in electric locomotives ... 74 Spruce : physical properties of 164, 166, 168 ties, amount purchased in the United States 156 cost of 156 Spruce pine, physical properties of 164 Spuyten Duyvil Rolling Mill Company, early steel rails 4 St. Etienne Works, Harmet process at 415 St. John, I. M., report on steel rails 5 St. Louis and San Francisco Railroad: articulated compound engine 34 plantations of tie timber 112 size and spacing of ties 121 ten-wheel type engine 33 St. Louis, Brownsville and Mexico Railway, size and spacing of ties 121 St. Louis Southwestern Railway, size and spacing of ties 121 Stamping rails 446 Standard drop testing machine 290 Stanton and Bairstow, experiments on re- peated stress 281 Stassano electric furnace 385 State Railways of France (see also Road in question) . concrete ties on 105 State Railways of Germany (see also Road in question). concrete ties on 105 rail fastenings on 144 rails and tie plates on 125 Static axle loads (see Axle loads). Stead, granular structure of metals 271 Steam: effect of, on ties 158, 162 engines (see Locomotives), loss in reversing, engines for rolling mills 459 shovels, used in mining iron ore 351 use for compression of ingot 415 Steaming, effect of, on strength of wood 158, 162 Steel: r (see Bessemer). which take place during cooling 426 compression strength (see Compression). cooling curve of 426 ductility of (see Ductility). effect of chemical composition on physi- cal properties (see Element in ques- tion). Steel: effect of mechanical work on strength of 424, 427 repeated stress on strength of 276 size of grain on strength of 424 temperature on strength of 284 electric (see Electric). eutectoid 427 granular structure of (see Grain) . heating curve 426 hyper eutectoid 427 hypo eutectoid 427 manufacture of (see Manufacture). open hearth (see Open hearth), rails (see Rail), special (see Special steels), strength of (see Strength). tensile strength (see Tension) . ties (see also Tie in question) 90 Steel Manufacturers of America (see Asso- ciation of American Steel Manufac- turers). Stetson, E. E.: flat spots in wheels 56 horizontal pressure on the rail 257 Stevens, Robert L., inventor of T-rail 6 Stock car 83 Stone: ballast (see Ballast). used in blast furnace 363, 364 weight of 316 Stoughton, B., piping and segregation 411 Stoves for blast furnace 359 Straightening press 446 rails 446 Strain, influence of, on strength of rail steel 270 Street railway: cars used on 87, 88 rails, corrugations in 209 sections of 19 specifications for 491 use of manganese in 339 roaring rails 209 ties purchased by 154 welded joints on 267 Stremmatograph tests 71, 212, 236 Strength: of electric steel 386 rail, as shown by drop test 293 calculation of 239 tests of 288 steel compression (see also Compression). effect of cold on 284 influence of stress and strain on 270 554 Strength: steel in rail 306 in rail head 193, 205 special (see Steel in question). tension (see Tension), ties (see Ties). track 317 wood 158, 164, 166, 168 bending in rail (see Bending moment). calculation of rail 239 effect of low temperature on rail 262, 288 repeated, Ewing and Humfrey's experiments 274 Ewing and Rosenhain's experiments 273 Howard's experiments 278 Spangenberg's experi- ments 277 Watertown Arsenal experiments 278 Wohler's experiments. 277 extreme fiber (see Extreme fiber stress). in German rails 218 influence of, on strength of rail steel 270 lines of principal 251 proposed solutions of rail 210 rail 193 at point of contact with wheel 193 calculation of, by Love 240 effect of cold on 288 friction of joint on 262 inertia of track on 68 joint on 259 position of wheel load on 230 influence of kind of ballast on 229 produced by rolling 435 shearing (see Shear). stremmatograph, determined by 212, 236 tests to determine rail, by Dudley. ... 212, 236 by U. S. Govern- ment 218 stremmatograph 212, 236 tie 171, 177 on German railways 218 U. S. Government tests on rail 218 web, discussion of, by Hiroi 247 working rail 312 wood, compression under rail .... 171 in cross bending 168, 171 Stripping ingots 397 required at iron ore mines 351 Stubbs, F., influence of copper on steel .... 331 Styffe: drop testing machine 288 experiments on effect of cold on rails. . . . 284 Subgrade: bearing power of 187, 317 depression of, U. S. Government experi- ments on 224 distribution of load to 180, 185 effect of heavy traffic on supporting power of. 318 313 on rail breakages long ties used on weak 188 supporting power required for different classes of track 317 Suddenly applied load (see Dynamic). Sugar gum, plantations of, for tie timber. . 112 Sulphur: content in different iron ores 363, 364 rails of Bessemer steel. 11, 253, 310 open hearth steel 310 effect of, in steel 330, 390 removal of, from iron ore by roasting 344 segregation of 407 specifications for, in rails (see also Specifi- cations) 328, 467 Support of the rail 90 Supporting power of ballast 180 of soils 313 of the subgrade 180, 313 of the subgrade required for different classes of track 317 of the track 188, 191, 317 Swedish Government Railroads, reinforced joint 264 Swedish iron: effect of repeated stress on 274 structure of 270 Sweet gum, physical properties of 164 T-rail (see also Rail) : examples of American 6, 10, 14, 18, 460 English 19 European 18, 19 for street railways 19 high, examples of 19 specifications for 491 inventor of 6 Talbot, A. N., experiments on distribution of pressure through gravel 187 Talbot, Benjamin: advantages of open hearth furnace 382 comparison of Bessemer and open hearth processes 380 continuous process of making steel 375 English practice of rolling rails 434 segregation, effect of aluminum on 405 Tamarack: physical properties of 166, 168 555 Tamarack: . ties, amount purchased in the United States 154, 156 cost of 154, 156 Tamping, effect of, on elastic curve of tie. . . 177 Tangent, comparison of rail failures on, with curve 10 Technical Conventions of the Union (Ger- man), design of rails 19 Tee rail (see T-rail). Teeming (see Casting). Temperature: critical, in rolling 426 effect of, in casting 410, 413 rolling 427, 430, 434 on conversion of steel 366 strength of rails 284 finishing (see Finishing). means for measuring, in rails 434 Ten-wheel type engine: allowable axle loads 322 classification of 29 coupled, classification of 29 dimensions of 33, 72 effect of excess balance and angularity of main rod 36,42,70 speeds of 24, 25, 26, 70 strength of track required for 322 typical dynamic wheel loads 73 wear of tires 198 weight of rail required for 322 weights of 33, 72 Tenacity (see Tension). Tender: effect of, on pressure of drivers 71 weights of 32, 33, 34 Tennessee Central Railroad Company, size and spacing of ties 121 Tennessee Coal, Iron and Railroad Com- pany: rail mill 438, 444 shrinkage allowed at 444 teeming practice 399 Tension: stress in rails on American railways (see Stresses) . German railways 218 in ties on German railways 218 test pieces, standard, American Railway Engineering Asso- ciation 512 Engineering Stand- ards Committee . 487 Tension strength of iron-carbon alloys. . . . 329 Tension strength of special steels (see Steel in question) . Tension strength of steel 306 effect of size of grain on 424 influence of chemical composition on (see Element in question). Texan oak, physical properties of 164 Thermal cracks in head of rail 205 Thermoelectric measurements of stress 311 Thiollier helical lining 148, 150 Three-high mill 437 Thurston, R. H.: arrangement of Bessemer plant 369 location of blast furnace 345 strength of materials 311 Tie plates: allowable load under 170, 171 American 122 European 125 experiments in Germany 133 felt, on L. & N. W. R 19 function of 122, 133 tests at Purdue University 169 by American Railway Engineering Association 169 on McKee 122 wooden 132 Tiemann, H. D., testing by impact 293 Ties: allowable load on, as determined by bear- ing on subgrade 188 allowable load on, as determined by bear- ing strength under rail 171 allowable load on, as determined by ex- treme fiber stress in bending 179 allowable load on, as determined by safe bearing on ballast 180 amount used annually in the United States 154, 156 annual charge of 115 bearing of rail on 122, 171 effect of dynamic load on 189 bending moment in 171, 177, 179 effect of dynamic load on 189 composite, used in Cuenot's experiments.. 173 composition (see also Tie in question) 96 concrete (see also Tie in question) 97 service tests on 104 cost of 154, 156 Cuenot's experiments on 172 depression of, in ballast 172, 176, 189 on German railroads 218 U. S. Government experiments . 219, 222, 233 distribution of load in 118 effect of dynamic load on 189 elastic curve of 172, 176, 177 granite 90 half-round 116 Ties: holding force of spikes in 138 kind of wood required for different classes of track 188,317 kinds of wood used for 154, 156 life of, in track 115 metal (see also Tie in question) 90 permissible load under tie plate 171 pole 119 preservation of (see Treated ties). | reaction of, in track 191 i size and spacing of, for different classes of track 317 size of, on American railways 121 German railways 218 L. &N. W. R 19 spacing of, on American railways 121 German railways 218 L. &N. W. R 19 steel (see also Tie in question) 90 strength of 153 wood 158, 170 stresses in (see Stresses). supply of 106 supporting power of 188, 191 treated (see Treated ties). twelve foot, on muskeg swamp 188 U. S. Government experiments on depres- sion of, in ballast 190 wood, future supply of 106 wooden plug for 149 Tilting open hearth furnace , 375 Timber: supply of, for ties 106 in the United States 108 wasteful cutting of, for ties 116 Tirefond (see also Spikes, screw) 142 Tires: cylindrical and conical, comparison of ... . 6 defective (see Defective equipment). M. C. B. standard 7 wear of : 196 Titanium : influence of, on segregation , 405 ferro, analysis of 405 effect of, in casting steel 341, 405 Titanium steel: analysis of 340, 406 behavior of, at low temperatures 286 branding 447 cost of 341 ductility of 286 hardness of, as determined by the sclero- scope 300 rails, production of 341 strength of 287, 340 Toledo Terminal Railway, concrete ties on . . 104 Torrey continuous rail 268 Track: automatic inspector machine 45 bolt (see Bolt). classification of , 317 depression of, U. S. Government experi- ments on 219, 222, 233 effect of dynamic load on 189, 190 inertia of, on rail stresses 318 irregularities in, on wheel pres- sure 45 speed on 29, 189, 190 experiments by U. S. Government 218 loading for different classes of 322 principles governing design of 313 stremmatograph experiments 236 strength of 310 U. S. Government experiments 218 Trackman's surface, depression of rail below 190 Tractive force, effect of, on pressure of drivers 71 Trailing truck (see Truck). Train: effect of, on pressure of drivers 71 speeds of 21, 23 weights of 21, 23 Tram rails, examples of 19 Tramway rails, British standard 19 Transition points in cooling steel 426 Transportation: cost of ore 345, 349 docks used in ore 351, 357 effect of, on location of blast furnace plant . 345 of iron ore on Great Lakes 349 vessels used in ore 349 Transverse fissures in head of rail 203 Trap rock, tests on ballast of 184 Tread (see Tires). Treated ties: amount treated in the United States 157 cost of 115 strength of 158 U. S. Forest Service, tests on 158 Tree plantations 109 Trenail: Collet 148, 150 used on English railways 146, 147 Truck: allowable weights on 320 leading, on freight and passenger en- gines 32, 33, 34 trailing, on passenger engines 32, 33 weight of car 82, 89 on electric engine 79, 80 steam engine 32, 33, 34, 72 Trzynietz Iron Works (Austria), hardness tests at Tucket, influence of arsenic on steel Tup (see Drop test machine). Turneaure, Professor, impact tests on bridges Turner: sclerometer thermoelectric measurements of stress. 284, Twelve-wheel engine, classification of 29 Ulster and Delaware Railroad tie 104 Ultimate strength: of steel 306,312 effect of repeated stress on (see of wood 158, 164, 166, 168 Unciti, concrete tie 105 Union Pacific Railroad: consolidation type engine 34 plantations for tie timber 112 size and spacing of ties 121 speed of trains 25, 26, 28 Union Railroad, steel ties on 90 Union Steel Works: experiments on piping in ingots 399 Forsyth transferring ladle 390 United States (see also American) : forest service (see U. S. Forest Service). forests in 107 government tests on rail 218 Love on 240 ties used in, number, kind and value. 154, 156 timber, supply of, in 108 United States Census: distribution of lumber product in the United States 108 ties purchased in the United States 156 United States Ordnance Department, hard- ness tests United States Steel Corporation (see Plant in question). Universal metallic tie 94 Unwin, Professor, remarks on factor of safety 312 U. S. Forest Service: half-round tie, proposed by 116 holding force of railroad spikes 139, 152 strength of different woods 158, 164, 166 tests on treated ties 158 the hardy catalpa 110 ties purchased in the United States 154 timber supply of the United States 108 303 Vandalia Railroad: Mogul type engine . Pacific type engine . Vandalia Railroad: speed of trains 25 Vaughan, H. H., flat spots on car wheels . . . 55 Velocity of load, effect of 69 Vessels for transporting ore 349 Vignole rail 18 Voiron St. Beron Railway (of France), con- crete tie 105 Von Maltitz, E.: blowholes 389, 391, 404 effect of recarbonizing 391 Von Schrenk, H.: cross-tie forms 116 use of wooden tie plate 132, 133 Wabash Railroad: Atlantic type engine 32 speed of trains 25 Walker, W. R., agitation of steel in casting. . 390 Walnut, plantations of, for tie timber Ill Wanner pyrometer 434 Washington, Baltimore, Annapolis Railway, car used on 87 Water: contained in iron ore 360, 363 cooling curve of 425 effect of, on gravel ballast 187 strength of wood 168 subgrade 314 removal of, by dry blast of Gay ley 360 from iron ore by roasting .... 344 used in ballast tests, Pennsylvania Railroad 184 Water hickory, physical properties of 164 Waterhouse, G. B.: examination of strength of rail steel 309 titanium steel 340, 406 Water oak, physical properties of 164 Watertown Arsenal: examination of steel at different stages of rolling 420 experiments on repeated stress 278 tests on joints 260, 264 steel at different temperatures. . . 286 Wear of rails: Dudley's investigation of 326 form for reporting 517 iron 1, 2 Kirkaldy on 205 machine for testing 304 of similar chemical composition 327 Wear of tires 196 Web rail: principles governing design of 16 strength of 247, 252 steel from 307 558 Web rail: stresses (s< Weber, depression of tie in ballast 189 Weber joint 264 Wedding, experiments on nickel steel 334 Weight: ballast 316 cars 85, 89 locomotives, electric 74, 79, 80 increase in 15, 30 modern steam 29 of rail for different conditions of loading 310, 322 specifications for (see also Specification in question) 476 wood 158, 163 Welded joints 267 Wellington, A. M., on soft rails 328 Wellman tilting furnace 377 Welsh, Ashbel: rail section 5 report on steel rails 5 West Coast Railway of England, speed of trains 25, 28 West Jersey and Seashore Railway : experiments on horizontal component of wheel pressure 259 speed of trains 24, 28 West, T. D., manufacture of ear wheels 57 Western hemlock, physical properties of 166, 168 Western larch, physical properties of 166 Western Railway Club, flat spots on car wheels 60 Western Railway of France : screw spikes on 143, 144 Westinghouse, George, on electric loco- motives 74 Wheel: defective (see Defective equipment). dynamic load of (see Dynamic). effect of position of, on stresses in rail .... 230 flat spot in 54 horizontal pressure of, on curves 259 impact of 62 load (see also Axle loads) : dynamic augment of 69 effect of spacing of wheels on. . 247 maximum, allow- able on rail .. . 319 main, increase in pressure due to angu- larity of main rod 35 manufacture 57 path of, on irregular track 47 pressure of, on rail (see also Pressure) .... 21 spacing given in modern bridge specifi- cations 211 Wheel. spacing of cars 85, 89 locomotives 32, 33, 34, 72 stresses at point of contact with rail 193 tests on chilled car 57 tire wear 196 tread (see Tires). Wheel base: cars 85, 89 electric locomotives 79, 80 steam locomotives 32, 33, 34 Wheeling and Lake Erie Railroad, size and spacing of ties 121 White ash, physical properties of 164 cedar, physical properties of 164 elm, physical properties of 164 oak (see also Oak) : force required to pull spike from . . 139 physical properties of 164, 168 tie, annual charge of 115 pine, physical properties of 164, 168 spruce, physical properties of 166 Whitwell stove 359 Whitworth's process for compression of ingot 411,415 Whyte's classification of locomotives 29 Wickhorst, M. H.: blast furnace practice 363 comments on Howard's rolling tests 420 description of process of making Bessemer steel 374 description of process of making open hearth steel 378 energy dissipated in drop test 293 flow of rail head under wheel loads 205 grain in head of rail 432 strength of rail head and web 252 steel 304 Wille, increase in axle loads 15 Williams' process for compression of ingot 410, 415 Williams, R. Price, iron rails 1, 2 Willow oak, physical properties of 164 Winckler: depression of tie in ballast 189 elastic curve of tie 172 Wingham, influence of copper on steel 331 Winslow and Griswold, Bessemer Steel Works at Troy 4 Wire tests of Professor Goss 63 Wohler's experiments on repeated stress. . . . 277 Wolhaupter: joint 264 tie plate 122 Wood: ferrule for spike 19 future supply of 106 Wood: key for double-headed rail 19 preservation of (see Treated ties). specific gravity of 163 strength of 158, 164, 166, 168 effect of moisture on 168 steaming on 158 treatment on 158 test of, by American Railway Engineer- ing Association 169 tie (see Ties). plates 132 unit stresses recommended by American Railway Engineering Association .... 168 used for ties, kinds of 154, 156 weight of 158, 163 Working load, relation of, to ultimate strength 311 pressure, steam locomotives, 37, 40, 41, 42, 43, 44 Wiirttemberg State Railway (see Kingdom of Wiirttemberg State Railways). Wyandotte Rolling Mill, early steel rails ... 3 Yellow locust, plantations of, for tie timber . . Ill oak, physical properties of 164 Yield point (see Elastic limit). Yielding: coefficient of, in ballast on German rail- ways 218 of tie in ballast, amount of 172, 176, 189 effect of, on stress in rail 243 Zimmerman, H.: depression of tie in ballast 189 effect of dynamic loading 69 elastic curve of tie 172 stresses in the rail 217 Zinc chloride treatment (see Treated ties) . Zores iron 173 " N ° V V , " X v -. * l, ^ C* ^v *>* .y %. *< % *** <> ^ ^ ^ ^ .^ v v° °-<, ■^ ^ ,^%. ■'•/>, ^\ N " ;* ^ •^ ^ ^ „ > v> '^.oO ■4. -/* . \° °* ,0 O V < •^ '^ r»V s' ,, 'r. V ^ ^. '-., *• -f 1 \^ ^ , <$*%, LIBRARY OF CONGRESS ftl iiiiiiiuiiiiii 021 218 399 4