k YX^^c^b ■ V r ■ ' ' ’ ' / ' » * SPECIFICATIONS FOR QUADRUPLE-EXPANSION, SINGLE-SCREW ■ . ^ . V PROPELLING ENGINES, WITH BOILERS AND AUXILIARY MACHINERY, FOR THIRD-CLASS l'ORPEDO jJAT FOR BATTLE SHIP 4 4 TEXAS OF ABOUT 12 PONS DISPLACEMENT P" — - BUREAU OF STEAM ENGINEERING, NAVY DEPARTMENT, WASHINGTON, D. C. WASHINGTON : GOVERNMENT PRINTING OFFICE. * 1894. :A ;R:r,V . ' » , ; . . • R ■ .A ■ ■ ; DEPARTMENT OF '/(ML ES6\^ W ^earning anb JTabor. # § LIBRARY OF THE | University of ISiinois. CLASS. BOOK. volume:. # # # £.BAAS..wc*v H Books are not to be taken irbm the Library. (Succession No.... - 4 i i Digitized by the Internet Archive in 2019 with funding from University of Illinois Urbana-Champaign Alternates https://archive.org/details/specificationsfo00unse_5 SPECIFICATIONS FOR QUADRUPLE-EXPANSION, SINGLE-SCREW PROPELLING ENGINES, WITH BOILERS AND AUXILIARY MACHINERY, FOR THIRD-CLASS TORPEDO BOAT FOR BATTLE SHIP OF ABOUT 12 TONS DISPLACEMENT. _ BUREAU OF STEAM ENGINEERING, NAVY DEPAETMENT, WASHINGTON, D. C. WASHINGTON : GOVERNMENT PRINTING OFFICE. 1894. V V w A it ft i .1 &IOIVI III •<() V) | fsi; v ' LIST OF PLANS ACCOMPANYING THESE SPECIFICATIONS. Sheet No. 1 Sheet No. 2 Sheet No. 3 Sheet No. 4 Sheet No. 5 -♦♦♦- . General arrangement in engine room and fire room. . General arrangement of engines. . Condenser. . Air pumps. . Circulating pump and engine. (ii) , ■ * ■ ' INDEX Page. Par. Air-pressure gauge_ 27 60 Air pumps_ 17 33 Ash sprinkler_ 28 61 Attachments, boiler __ 24 49 Auxiliary exhaust pipes. 29 65 Auxiliary and main feed pumps__ 27 58 Auxiliary steam pipes.... 28 64 B. Bars, grate, and hearers. 22 45 Bearers and grate bars .. 22 45 Bearing, thrust__ 14 24 Bearings, mandrels for white metal_ 14 26 Bedplate_ 10 16 Bilge and sea connections 20 37 Blower, fire-room, and en¬ gine _ 27 59 Boiler.. 22 42 Boiler attachments_ 24 49 Boiler drain cocks_ 26 57 Boiler material_ 22 43 Boilers and machinery, tests of_ 35 85 Boiler water gauges_ 26 56 Bolts and nuts .. 31 74 Bottom and surface blow valves_ 25 53 Boxes, journal. 14 25 Boxes, piston-rod and valve-stem stuffing. i.. 8 12 Boxes, stuffing_ 15 27 Bulkheads, pipes through water-tight_ 30 70 C. Casting, distribution.... 25 51 Changes in plans and specifications. 38 91 Page. Par. Check valves, feed_ 25 52 Chests, valve_ 5 6 Circulating-pump_ 19 34 Circulating-pump engine 20 35 Cleaner, steam tube. 28 62 Clearances, cylinder_ 5 4 Clothing and lagging.... 31 75 Cocks, boiler drain_ 26 57 Cocks and valves. 30 72 Communication with en¬ gine room. 21 41 Completed machinery, drawings of_ 37 90 Condenser_ 16 32 Connecting rods... 9 14 Connections, hull_ 30 71 Connections, sea andbilge 20 37 Covers, cylinder_ 4 3 Covers, valve-chest_ 6 7 Crank shaft__ 10 18 Crossheads and slides_ 8 13 Cylinder clearances_ 5 4 Cylinder covers_ 4 3 Cylinder drain cocks .... 5 5 Cylinders. 3 2 D. Description, general. 1 1 Discharge and suction pipes_ 29 68 Doors and furnace fronts 23 46 Drain cocks, boiler_ 26 57 Drain cocks, cylinder.... 5 5 Drawings of completed machinery_ 37 90 Drawings, working_ 37 89 Drips, oil_ 16 31 Dry-pipe_ 24 50 Duplicate pieces. 33 82 (hi) . i - . IV E. Page. Engine and fire-room blower_ 27 Engine, circulating-pump 20 Engine frames_ 9 Engine indicators_ 21 Engine-room gong_ 21 Engine throttle and stop valve_ 15 Escape pipe_ 29 Exhaust pipes, auxiliary 29 Exhaust pipes, main_ 15 Feed check valves_ 25 Feed pipes_ 29 Feed pumps, main and auxiliary_ 27 Feed tanks_ 20 Fire-room blower and en¬ gine _ 27 Floors and platforms_ 32 Frames, engine_ 9 Furnace fronts and doors 23 G. Gauge, air-pressure_ 27 Gauge, steam_ 26 Gauges_ 31 Gauges, boiler water ____ 26 Gear, reversing_ 13 Gear, valve.. 12 General description_ 1 Gong, engine-room_ 21 Grate bars and bearers __ 22 H. Hull connections_ 30 I. Indicators, engine_ 21 Inspection_ 38 J. Joints, riveted_„_ 22 Journal boxes.. 14 L. Page. Par. Ladders_ 32 78 Lagging and clothing_ 31 75 Line shaft___ 11 20 Lubrication_ 15 30 M. Machinery, drawings of completed_ 37 90 Machinery, tests of boil¬ ers and_ 35 85 Main and auxiliary feed pumps.. 27 58 Main exhaust pipes_ 15 29 Main steam pipe_ 28 63 Main valves__ 7 10 Mandrels for white-metal bearings_ 14 26 Materials and workman¬ ship _ 33 83 Material, boiler_ 22 43 Material, tests of_ 35 84 Miscellaneous pipes_ 30 69 N. Nuts and bolts_ 31 74 O. Oil drips. 16 31 Oil tank_ 32 79 « P. Painting__ 36 86 Pieces, duplicate_ 33 82 Pipe, auxiliary steam.... 28 64 Pipe, dry_ 24 50 Pipe, escape_ 29 66 Pipe, main steam_ 28 63 Pipe, smoke___ 23 48 Pipes, auxiliary exhaust 29 65 Pipes, feed_ 29 67 Pipes, main exhaust_ 15 29 Pipes, miscellaneous. 30 69 Pipes, suction and dis¬ charge_ 29 68 Pipes through water-tight bulkheads.. 30 70 Par. 59 35 15 40 39 28 66 65 29 52 67 58 36 59 77 15 46 60 55 73 56 22 21 1 39 45 71 40 92 44 25 y Page. Piston-rocl and valve- stem stuffing boxes_ 8 Piston-rods.. 7 Pistons__ 6 Plans and specifications, changes in__38 Platforms and floors_ 32 Preliminary tests and trials_ 36 Propeller, screw_ 13 Propeller shaft and line shaft.. 11 Pump, circulating.__ 19 Pumps, air_ 17 Pump, circulating, engine 20 Pumps, main and auxil¬ iary feed.. 27 R. Record of weights_ 37 Reversing gear.. 13 Riveted joints_ 22 Rods, connecting_ 9 Rods, piston__7 S. Safety valve__ 25 Screw propeller. 13 Sea and bilge connections 20 Securing engine in vessel 21 Shaft, crank.. 10 Shaft, propeller_ 11 Shafts_ 10 Shaft, thrust.. 11 Slides and crossheads8 Smoke pipe_ 23 Specifications, changes in plans and__ 38 Sprinkler, ash_ 28 Steam gauge.. 26 Steam pipe, main_ 28 Steam tube cleaner__ 28 Stems, valve__7 Stop valves and distribu¬ tion casting_ 25 Stuffing boxes.. 15 Suction and discharge pipes_ 29 Surface and bottom blow valves_ 25 T. Page. Par. Tank, oil... 32 79 Tanks, feed_ 20 36 Tests and trials, prelimi¬ nary.. 36 87 Tests of boilers and ma¬ chinery _ 35 85 Tests of material .. 35 84 Throttle and stop valve, engine_ 15 28 Thrust bearing_ 14 24 Thrust shaft_ 11 19 Tools. 32 81 U. Uptakes. 23 47 V. Valve-chest covers_ 6 7 Valve chests.. 5 6 Valve gear_ 12 21 Valve, safety_ 25 54 Valve stems__ 7 11 Val ve-stem and piston-rod stuffing boxes_ 8 12 Valves and cocks_ 30 72 Valves, bottom and sur¬ face blow.. 25 53 Valves, feed check. 25 52 Valves, main... 7 10 Valves, stop, and distribu¬ tion casting_ 25 51 Ventilator_ 32 80 Vessel, securing engine in 21 38 W. Water gauges, boiler .... 26 56 Water-tight bulkheads, pipes through_ 30 70 Weights, record of_ 37 88 Whistle... 32 76 White-metal bearings, mandrels for_ 14 26 Working drawings_ 37 89 Workmanship and mater¬ ials.. 33 83 Par. 12 9 8 91 77 87 23 20 34 33 35 58 88 22 44 14 9 54 23 37 38 18 20 17 19 13 48 91 61 55 63 62 11 51 27 68 53 . / ' SPECIFICATIONS OF MACHINERY FOR THIRD-CLASS TORPEDO BOAT FOR BATTLE SHIP 66 TEXAS.” 1. GENERAL DESCRIPTION. There will be one propelling engine of the quadruple- expansion type, working a single screw. It is estimated that the indicated horse power of this engine will be about 155 when the screw is making 675 revolutions. The engine will be vertical, inverted, with the cylinders placed in order of size over the shaft, the high-pressure cylinder being forward. The diameter of the cylinders will be : High-pressure, 5 A inches; first intermediate- pressure, 7^ inches; second intermediate-pressure, 10 inches; low-pressure, 14 inches; with 8-inch stroke of piston. The cylinders will be fitted with one piston valve each, excepting the low-pressure, which will have a double- ported slide valve; the high-pressure and first interme¬ diate-pressure piston valves to be made without rings, and the others to be fitted with broad adjustable rings. The valves will be worked by three Stephenson links, the two forward valves from the same link. The crank shaft will be made in one piece, with the cranks of the high-pressure and first intermediate-pressure placed ex¬ actly opposite each other, and the cranks of the second intermediate-pressure and low-pressure opposite each other and at right angles to the first two. The reciprocating parts connected with opposite cranks will have the same weight in order to lessen vibration, the high-pressure and second intermediate-pressure pis¬ ton being thickened for that purpose. (l) v ft A I: EEj I : i o v, i.Ui •< D vi i A it s V i v u - pH I ♦ . ' 2 The shafts and working parts generally will be forged of mild open-hearth steel, the piston and connecting rods, and valve stems to be oil tempered. The shafts and crank pins will be hollow. The framing of the engine will consist of forged-steel columns stayed by diagonal braces in such a way as to give firm supports to the slides. The engine bedplate will be of plate steel, supported on keelson plates built in the vessel, and stiffened by angle irons running fore and aft on each side of engine. The condenser will be made entirely of composition and copper, and will have a cooling surface of about 116 square feet measured on the outside of the tubes, the water passing through the tubes. There will be two double-acting air pumps worked by eccentrics on the for¬ ward end of the main shaft. The circulating pump will be of the centrifugal type, worked independently, and of sufficient capacity to condense all the steam generated in the boiler when lying idle. The circulation when going ahead or astern will be maintained by means of scoops over the injection and outboard delivery. The propeller will be of manganese bronze or approved equivalent metal. There will be one water-tube boiler placed in a separate compartment forward of the engine. It will be con¬ structed for a working pressure of 250 pounds per square inch, and have about 9^ square feet of grate surface, with 372 square feet of heating surface. The forced-draft system will consist of one blower located on the after bulkhead, and discharging into a closed fire room. Bulkheads and doors will be fitted, where necessary, to make the fire room air-tight. There will be one smoke pipe, located as shown on the drawing. The main feed pump will be placed in the fire room, and an auxiliary feed and bilge pump in the engine room, both delivering into the main feed pipe. Two feed tanks of a combined capacity of 70 gallons will be provided and located as shown on the general plan. ■ • ' ; ’ 3 There will be such fittings and supplementary parts as are necessary with the above machinery and boilers. The weight of all machinery and boilers, including auxil¬ iaries and water in boilers, condensers, and pipes, also spare parts and tools, will not exceed 9,900 pounds. All parts will conform to the following detailed speci¬ fications and the accompanying drawings. Any part of the machinery, or any article pertaining thereto, which may be inadvertently omitted from these specifications, or from the official drawings, but which is necessary for the proper completion of the vessel and successful running of the machinery in accordance with the best engineering practice, is to be supplied by the contractor without extra charge. 2. CYLINDERS. The cylinders will be made of the best quality of cast iron, as hard as can be properly worked. The high-pres¬ sure and first intermediate-pressure will be in one casing, rigidly secured by body-bound forged-steel bolts to the second intermediate-pressure and low-pressure cylinders, which will likewise be cast in one casing. The casings will include the valve chests, steam ports and passages, the lower heads, and the various flanges and brackets for attaching the supports and securing the cylinders to¬ gether. The steam and exhaust ports will be smoothly cored to the dimensions shown in the drawing. The high-pressure and first intermediate-pressure cyl¬ inders will be cast with centers as near 18% inches apart as possible, and will be subsequently bored to exactly this dimension; the second intermediate-pressure and low- pressure cylinders will be cast with centers about 23 inches apart, and will be bored to this dimension; and the flanges for securing the casings to each other will be so faced, that when bolted together the centers of the first intermediate-pressure and second intermediate-pressure cylinders will be inches apart. All of the cylinder axes will be in one plane and parallel. The barrels of the high-pressure and first intermediate- pressure cylinders will be ^4 inch thick, the other two ■ ■ 9 . ' * ' • 4 inch thick. They will be counter-bored at both ends, leaving the working bore 8% inches long. The counter bore will be very carefully cut to the dimensions shown, and tapered gradually down to the bores of the cylinders, so that the piston rings can not catch at either end should the piston be dropped down to the lower head. The brackets at the base will be well ribbed and truly faced and bored for the supporting columns, as shown, and there will be facings for cylinder and valve-chest covers, steam and exhaust pipes, one receiver live steam pipe, one receiver safety valve, drain cocks, indicator pipes, and oil cups. The high-pressure, first intermediate-pressure, and second intermediate-pressure cylinders, will be bored without liners to 5^, 7^, and 10 inches, respectively, and each will have one piston valve chest fitted with liners, as shown, bored accurately to 2^ inches diameter for the high-pressure, 3)4 inches diameter for the first inter¬ mediate-pressure, and 5|4 inches diameter for the second intermediate-pressure cylinders. The low-pressure cyl¬ inder will be bored without a liner to 14 inches diameter, and will have a common double-ported slide valve, as shown, without a separate seat bolted to the cylinder. The walls of the steam passages will be stayed as shown, with ribs cast in with the casings. All steam and exhaust passages must be thoroughly cleaned out and pickled, and care taken that the passages are nowhere contracted to less than the areas shown on the drawings. 3. CYLINDER COVERS. The covers will be of cast iron for all cylinders, about yq inch thick, and well stiffened by )^-inch ribs. The lower heads, cast with the casings, will be faced and bored for piston-rod stuffing boxes, for the supports of the upper end of the crosshead guides, and for the low- pressure valve-stem stuffing box. Both the fixed and movable heads will be shaped to leave as little clearance as possible. Each cover will be 270-2 * / '• ■ -, 1 • ' 5 turned and faced to fit its cylinder casing, and finished on the outside of the flange. The cover of the high-pressure cylinder will be secured to the cylinder casing by eight bolts, that of the first intermediate-pressure by ten, that of the second inter¬ mediate-pressure by fourteen, and that of the low-pres¬ sure by nineteen; all to be -^--inch steel studs. Holes will be drilled and tapped for forcing bolts and eyebolts. 4. CYLINDER CLEARANCES. Great care will be taken to make the clearances no larger than absolutely necessary. The total clearance of both ends will not be above % inch, distributed between top and bottom to the best advantage. After the engines are set up in place and connected, the volume of the clearance at each end of each cylinder will be carefully measured by filling the space with water or oil, and the volume in cubic inches plainly marked on some con¬ spicuous part of the cylinder easing. Marks will be made on the crosshead guides showing the position of the erosshead when the clearances were measured, and likewise when the pistons strike the heads, the connect¬ ing rod being disconnected for the latter purpose. 5. CYLINDER DRAIN COCKS. Each cylinder will be fitted with a inch approved cock, placed so as to drain the bottom of the cylinders thoroughly. All these drain cocks will be worked by one lever near the reversing lever, and a drainpipe will lead to the fresh-water side of the condenser, with a branch to the bilge. Both branches of the drainpipe will be fitted with straightway stop valves. 6. VALVE CHESTS. All valve chests will be fitted with suitable composi¬ tion drain cocks, with discharge pipes to the feed tank. The low-pressure receiver will have a i-inch adjustable- spring safety valve of approved pattern, and a 24 -inch live-steam pipe with stop valve will be led to the second receiver. . 6 The steam ports will be as shown in the drawings, and the edges of all ports will be carefully finished to a uni¬ form outline. 7. VALVE-CHEST COVERS. The valve-chest covers will be made of cast iron, ribbed where necessary for strength. They will be fitted to the openings in valve chests, and all flanges will be faced and finished on the outside and edges. The lower covers of the high-pressure, first intermediate-pressure, and second intermediate-pressure, will be faced and bored to receive the valve-stem stuffing boxes, and for securing the valve-stem crosshead guides. 8. PISTONS. The first intermediate-pressure and the low-pressure pistons will be made of forged steel, dished as shown. They will be reduced to the lightest possible dimensions consistent with strength. No excess of weight over that due to the dimensions shown in the drawings will be allowed. The high-pressure piston will be made of cast iron or forged steel, of such thickness as to weigh, when com¬ pleted, exactly the same as the first intermediate-pres¬ sure piston. The second intermediate-pressure piston will likewise be made of cast iron or forged steel, and will have the same weight completed as the low-pressure piston. All the above pistons will be carefully weighed after the rings are in place. Each piston will be fitted with two packing rings inch wide, placed % inch apart; the high-pressure to be inch thick; the first intermediate-pressure % inch thick; the second intermediate-presssure •£% inch thick; and low-pressure ^4 inch thick. The rings will be made of hard cast iron, cut obliquely and sprung in without a follower, the joints being placed opposite. Each piston will be fitted accurately to the bore of its cylinder, not above inch play being allowed. Two holes will be drilled and tapped for ^4- inch eyebolts on opposite sides of the boss of each piston, to facilitate removal. . ■ ’ ■ ' 1 7 9. PISTON RODS. The piston rods will be made of mild steel having about 80,000 pounds tensile strength, and 20 per cent, elongation in 2 inches. They will be oil tempered and ground accu¬ rately to inches diameter in the body for all cylin¬ ders. The upper ends will be turned and ground to fit the pistons accurately, and each will be secured by means of a forged-steel nut, having a split pin to prevent its back¬ ing off. The lower ends of each piston rod will be forged into a stub end, and will be fitted with binders, bolts, and brasses to hold the wrist pins. 10. MAIN VALVES. The low-pressure cylinder will be fitted with a cast- iron double-port slide valve. All other cylinders will have piston valves of cast iron, the thickness to be as shown on the drawings. The high-pressure and first intermediate-pressure valves will be made with two heads separated by a steel distance piece, and the second inter¬ mediate-pressure valve in one piece, havinghub and spider at each end for securing to the valve stem. The hub and spider will also form the follower. The high-pres¬ sure valve will be 2^ inches in diameter, and fitted accu¬ rately without rings to the bore of the valve chamber. The first intermediate-pressure valve will have a diam¬ eter of 3^4 inches, and be fitted accurately without rings to bore of cylinder. The second intermediate-pressure valve will be 5^4 inches in diameter, and each head will be packed with one cast-iron ring and follower, as shown. The steam and exhaust lap and lead will conform to the diagrams and drawings. 11. VALVE STEMS. The valve stems will be of forged steel, oil tempered and ground, the low-pressure 1 inch in diameter in the stuffing box, and the others ^ inch- They will be secured to the valves as shown. The low-pressure stem will have a sleeve working in a stuffing above the valve, of sufficient size to balance the valve and take the weight off the link. . • / 8 The high-pressure and first intermediate-pressure stems will be secured to the same crosshead, which will be formed into a stub end at the lower end, for the wrist pin, and into a rod at the upper end for an efficient guide. The second intermediate-pressure and low-pressure stems will be formed "into stub ends at the lower end for the wrist pins, and will be guided as shown. The thread on the upper end of each stem must be sufficiently long to allow a reasonable amount of adjustment, and a split pin will be put through the stems to prevent the nuts from backing off. The stub ends will be provided with a com¬ position cap and bushing for the bearing of the wrist pin, and the cap will be secured with two steel bolts with nuts held in place by split pins. 12. PISTON-ROD AND VALVE-STEM STUFFING BOXES. The stuffing boxes will be of cast iron, with composi¬ tion bush and gland. They will be packed with approved metallic packing. Wherever practicable the packing of all engine stuffing boxes, including valve stems, will be made in two independent sections, so that in case of injury to one, the other will make a tight joint. This packing is to be equal to the best in the market, and sub¬ ject to the approval of the Bureau of Steam Engineer¬ ing. The gland bolts will be fitted with approved means of adjustment while the engines are in operation, and lock nuts and split pins will be provided. 13. CROSSHEADS AND SLIDES. The crossheads will be forged with the piston rods, and the bearing for the connecting-rod wrist pins will be formed in the crossheads as shown. The back of each crosshead will be shaped into a shoe 3^ inches broad by 4 inches long, and % inch thick at the sides. The sides will be tapered toward the center, where the thickness will be inch, and the bearing, when backing, will be taken on two composition gibs. The back of the shoe for taking go-ahead pressure will have two white-metal blocks let into the steel inch, and standing above its surface inch. These blocks will be inches broad and will run across the face of the shoe, leaving an oil groove y inch broad between them. ■ , 9 They will be thoroughly hammered into contact with the steel. There will be no gibs or liners on the cross¬ head. The slides will be of cast iron with backing gibs of composition, the whole to be fitted as shown. All parts of the sliding surfaces will be smoothly and accu¬ rately finished, and the composition gibs will be finished all over. The guides will be bolted to brackets carried on the columns and to facings on the cylinders. Brass oil boxes will be provided for supplying oil at both ends of the guides. 14. CONNECTING RODS. The connecting rods, with their caps and bolts, will be of forged-steel, finished all over. The rods will have a 24-inch hole drilled longitudinally through the center for oiling the crank pin, and will be oil tempered. They will be 20 inches long between centers, forked at the upper end with crosshead pin secured firmly in the jaws. The crosshead pins will have a bearing surface of inches diameter by 2^4 inches long. The body of the rods will be turned to i3/£ inches diameter at the upper ends and 154 inches diameter at the crank-pin ends, the sides being faced off to a uniform thickness of i^4 inches. Crank-pin brasses will be fitted, as shown, with distance pieces inch thick between the two halves. They will be so fitted as to be removable without taking out the cap bolts. The crank-pin brasses will be lined with white- metal blocks dovetailed and hammered in, so that the pins will have a bearing only on white metal. Ample oil ways will be provided. 15. ENGINE FRAMES. Each cylinder will be supported by four forged-steel columns, excepting over the middle bearing, where two columns form the supports between the two intermediate- pressure cylinders. The tops of the columns will be turned and faced to fit the facings and lugs on the cylin¬ ders, and the feet of the columns fitted to faces on the main bearings. They will be secured as shown on the drawing. The columns will be stiffened by steel tie-rods, and the crosshead guides will be secured as shown. 10 16. BEDPLATE. The bedplate will consist of a single ^-inch steel plate, cut away for the swing of the cranks and eccentrics, and stiffened on the top by a fore-and-aft angle iron, inch by iy 2 inches by % inch, on each side, against which the diagonal braces abut. This plate will rest on yellow-pine liners about inch thick, and will be firmly secured to transverse frames built up for that purpose. The main pillowblocks will be made of composition, with lugs on the sides for securing the columns, which will extend en¬ tirely through the angle irons on the frames and have a nut below, as shown. Each binder bolt will have a square collar, as shown, in the lower half of the pillow block, and will be secured by a nut below the frame angle iron. The upper and lower half of the pillow blocks will be lined with white metal, fitted in dovetailed recesses and hammered in place. They will have ample oil grooves. The pillow blocks will be fitted to the bedplate and will then be bored in place to fit the journals of the shaft. Each cap will have holes of sufficient size for the tubes of the oil boxes. All brasses will be so fitted that the only bearing of the journals will be on white metal. The binder bolts will be of forged steel inch in diameter. 17. SHAFTS. All the sections of the shaft will be of forged steel. Each length will be forged solid in one piece and will have a hole drilled axially through it from end to end. 18. CRANK SHAFT. The crank shaft will be 7 feet 1% inches over all, and will be made in one piece. The after end will have a coupling disc y inch thick by 6 % inches diameter, forged solid with the shaft. This coupling will have square notches between the bolts and be provided with a spanner for turning the engine by hand. The forward end will project about sy inches beyond the forward bearing, and will be increased to 3^ inches diameter for the seat- •r« >- *' • '' . 7 ; ‘ . -f> ; v. ; : > > ’ i 11 ing of eccentrics by which the air pumps are driven. There will be a journal on each side of each crank, 3 inches in diameter by 3 inches long, excepting between the two intermediate cylinders, where there will be one journal 3 inches in diameter and 5 inches long. The eccentric seatings will be 3^ inches in diameter by 2^ inches long for the low-pressure gear, and 2% inches for those of the other cylinders. The crank pins will be 3 inches in diameter by 3^2 inches long for all cylinders, and the crank webs 3^ inches wide by ij/4 inches thick. The crank pins must be accurately turned parallel to the journals, with centers 4 inches from the center of the shaft. All wearing surfaces must have a smooth finish, and the accuracy of alignment of shaft and bearings must be proved. There will be a hole 2^ inches in diameter bored axially through the shaft and crank pins. There will be six coupling bolts, ^ inch in diameter, made of forged steel, finished to fit the holes snugly, and each fitted with forged-steel nut and split pin. All parts will be completed in accordance with dimensions shown on the drawing. 19. THRUST SHAFT. The thrust shaft will be 2^6 inches in diameter and about 3 feet 7 y 2 inches over all. There will be a coup¬ ling forged solid on each end of the shaft similar to that on the crank shaft, and the same number of coupling bolts of the same diameter in the after end. There will be five thrust collars inch thick, spaced y inch apart, with an outside diameter of 4--^ inches. There will be a hole inches in diameter bored axially through the shaft. 20. PROPELLER SHAFT AND LINE SHAFT. The propeller shaft will be 2^ inches in diameter and about 9 feet inches over all. Its exact length will be taken from the boat. It will have raised surfaces 3 inches in diameter for the bearing in the stern tube, as shown. There will be a hole 2^6 inches in diameter bored axially from end to end, and the after end will be drawn 12 down for the taper in the hub to hold a i^-inch stud bolt screwed into the shaft for securing the propeller. The end will be tapered to fit the bore of the propeller hub and will be fitted with two fore-and-aft steel keys. The stud and nut will be securely pinned in place. The forward end of the shaft will have a composition coupling 2% inches thick by 6% inches in diameter, screwed on and keyed in place. A composition stuffing box will be riveted to the forward end of the stern tube with a gland and bushing of composition. The packing space will be about 4% inches deep and inch wide and will be packed with the best quality of hemp packing. The fol¬ lower bolts will be of rolled manganese or Tobin bronze. The stern tube will be made of a lap-welded steel tube 4 inches in diameter and inch thick, which will be secured to the frames of the vessel. The bearings will be made of white metal, as shown, run in around a mandrel of the proper size, and will not be bored. There will be a bearing in each end 12 inches long. The white metal will be held in place by screws tapped through the tube and entering the white metal. The line shaft will be 8 feet 9 inches long, with the same diameter as the propeller shaft. 21. VALVE GEAR. The valve gear will be of the Stephenson type with double-bar links, and the adjustment will be such that the mean cut-off for both ends of each cylinder will be about .75 stroke. The eccentrics will be of cast iron, each in two parts, neatly fitted together and secured by two forged-steel bolts. They will be bored to a snug fit on their seatings and turned on the outside to an eccentricity of 1 ^4 inches for the high-pressure, first intermediate-pressure, and second intermediate-pressure cylinders, and 1 inch for the low-pressure cylinder. All eccentrics will be re¬ cessed at each side for the flanges of the straps and will be secured on the shaft by keys. The eccentric straps will be of composition, finished all over, made with flanges to fit the recesses of the eccentrics, and with lugs for the bolts and the eccentric 270—3 13 rods. The two parts of each strap will tance piece between them, and will be held' two steel bolts with finished heads, lock nuts, ana spJ pins. Each strap will have white-metal lining, will be bored to fit the eccentric accurately, and will be chan¬ neled for oil. The eccentric rods will be of forged steel, finished all over. Each rod will be secured to the eccen¬ tric strap by means of a T on the lower end and two steel stud bolts, with nuts locked in place. The upper end of the rods will be formed to span the link, and fitted with brasses. The ' two brasses will be bored accurately in line for the e^ank pins. The rods will be 18 inches long between centers. The main links will be of the double¬ bar pattern, of forged steel, finished all over. The pins for the eccentric rods will be 6 inches between centers. The pins for the suspension bars will be as shown in the drawings. The link blocks will be of forged steel, finished all over, with composition gibs fitted accurately to the curve of the links to take the bearing. Each link will be suspended from the corresponding arm of the reversing shaft by two flat-sided forged-steel suspension links. The ends will be fitted with composi¬ tion bushings bored to fit the corresponding pins. 22. REVERSING GEAR. The engine will be reversed by hand gear fitted as shown. There will be one forged steel reversing shaft supported in bearings bolted to the engine columns. The bearings will be made of forged steel without bush¬ ings. There will be one arm for each link securely keyed to raised seatings on the shaft, and a reversing lever for¬ ward of the high-pressure cylinder. This lever will have a spring latch of approved pattern, and an arc with notches for full gear ahead, backing, and mid gear, also for linking up when going ahead. 23. SCREW PROPELLER. The screw propeller will be of manganese bronze or approved equivalent metal. The hub will be accurately ' . :A : ■ "" ' ■ r J rv wnMH . ' - - | . 14 fitted to the taper on the after end of the shaft, and will be finished on the after end by a conical composition cap forming part of the securing nut. The screw will be four-bladed, 35 inches in diameter, with a pitch of 36^ inches, and helicoidal area of 3.6 square feet. The blades will have all roughness removed and will be as smoothly finished, as possible. A rolled zinc protecting ring, ^4 inch thick by 6 inches diameter, will be secured to the stern post by tap bolts forward of the hub. 24. THRUST BEARING. The thrust bearing will consist of a casting bolted to a soleplate which will be firmly secured to the boat. There will be six rings for taking the ahead and back¬ ing thrust. They will be so fitted as to bear equally on the collars of the shaft. The lower part of the casting between the rings and soleplate will be cored out to form an oil pocket in which the collars will run. Small holes will be drilled and plugged, so that this passage may be washed out without lifting the shaft. The oil box will be cast with the cap, and an oil tube will be provided for each collar. The collars will likewise be grooved for oil. The whole will be covered by a light brass cap. There will be lugs cast on the soleplate with bolts or wedges forward and abaft the thrust block, for adjust¬ ing it, and the block will be bolted to the soleplate by bolts on each side passing through oval holes in the block. 25. JOURNAL BOXES. All journals or moving parts of iron or steel will run, unless otherwise specified, in composition boxes. These boxes will be lined with approved antifriction metal where directed, fitted in dovetailed recesses and ham¬ mered in place. All adjustable bearings will be provided with channel-brass chipping pieces, securely held in place and easily removable. 26. MANDRELS FOR WHITE-METAL BEARINGS. A hollow cast-iron mandrel will be furnished for form¬ ing the white-metal lining of the crank pin and crank¬ shaft bearings ; also a hollow cast-iron mandrel for form- ■ / - 1 15 ing the white-metal bearings in the stern tube. These mandrels will be smoothly and accurately turned to the size of the journals, and packed so as to be protected. 27. STUFFING BOXES. All auxiliary stuffing boxes will be fitted as specified for the main engine so far as practicable, using metallic packing in all cases. Approved means of adjustment while engines are in operation will likewise be provided. A composition stuffing box and gland, made in halves and packed with hemp, will be placed around the shaft in the bulkhead abaft the engine room. 28. ENGINE THROTTLE AND STOP VALVE. There will be a throttle valve, designed to give the full opening of the steam pipe, bolted to the high-pressure cylinder casing and worked by a lever within easy reach from the reversing lever. It will have an index to show the position of the valve and a clamp to hold it in any position. A 124-inch stop valve, steam tight for all pres¬ sures, will be placed next the throttle valve. It will be worked by a wheel or lever. 29. MAIN EXHAUST PIPES. Two 2%-inch copper pipes of No. 13, B. W. G., will lead from the first intermediate-pressure to the second inter¬ mediate-pressure cylinder; two 3-inch copper pipes of No. 15, B. W. G., from the second intermediate-pressure to the low-pressure cylinder ; and one 5-inch copper pipe of No. 16, B. W. G., from the low-pressure cylinder to the con¬ denser. The exhaust passage from the high-pressure to the first intermediate-pressure cylinder will be cast in the casing. 30. LUBRICATION. All working parts of the machinery will be fitted with approved lubricators, each with sufficient capacity to run a reasonable length of time; each lubricator to be fitted with a tube leading to wipers on the moving parts, or tubes in the bearings and guides. Unions will be fitted where necessary, so that the oil pipes may be quickly taken down and cleaned. Each . . ' . . ' 16 main crank pin will be oiled by pipes and cups carried on the crossheads, taking oil from sight feed cups over¬ head, the oil to be carried to the crank pins through the hollow connecting rod. These pipes will have union joints where connected to oil cups. Each main crosshead journal will take oil from an overhead wick cup. Each crosshead guide will be oiled by pipes leading to about the middle of each forward and each backing face. Each eccentric will have an oil cup so arranged that the eccentric will be oiled in all positions. So far as possible, all the oil for the moving parts of the main engine, except the main bearings, will be supplied from one oil box on the side of the cylinder, with sepa¬ rate valve or cock, sight feed and pipe, for each part to be oiled. All working parts for which oil cups are not specified or shown in the drawings will have oiling gear of approved design, such that they can be oiled without slowing. The auxiliary engines will be oiled in an ap¬ proved manner. For oiling the cylinders oil cups will be provided in the main steam pipe and on the low-pres¬ sure steam chest, of such a pattern that the oil can be forced in against the steam pressure. All oil cups will have removable covers with stops to prevent their com¬ ing off when the engine is running. All oil cups and their fittings will be of finished cast brass, sheet brass, or copper, as may be directed. 31. OIL DRIPS. All fixed bearings will have drip cups cast on where possible, otherwise they will be of sheet brass properly applied. All moving parts will have drip cups or pans attached to the engine frames, or where directed. They will be substantially made of sheet brass or copper. All drip cups or pans will have drainpipes and cocks at least y 2 inch in diameter, which can be used while the engine is in operation. 32. CONDENSER. The condenser will be cylindrical, of copper, No. 16, B. W. G., about 14^4 inches external diameter and 4 feet 3 s . • ' . ' 17 inches long between tube sheets. The tube sheets will be made of composition inch thick with smoothly fin¬ ished holes for the tubes, tapped and fitted with screw glands for packing the tubes. The glands will be turned in at the outer ends, to prevent the tubes from crawling, and will be slotted to admit a tool for screwing up. Cot¬ ton-tape packing will be used. There will be 167 seamless drawn-brass tubes in the condenser, $/% inch outside diameter, No. 20, B. W. G., in thickness. They will be 4 feet 4^ inches in length over all, and will be spaced yf inch between centers. The cool¬ ing surface will be about 116 square feet, measured on the outside of the tubes. The longitudinal seams will be brazed and the tube sheets will be secured to the flanges by rolled manganese or Tobin bronze bolts, which will also serve for holding on the circulation water bonnets. Four of these bolts will be collar bolts to hold the tube sheets in place when the water chests are removed. The water chests at the ends of the condenser will be of composi¬ tion, as shown. There will be the following openings in the condenser, with properly faced flanges: One for the exhaust pipe, 5 inches in diameter; one for the exhaust from the auxil¬ iaries; one for the air-pump suction, 1^ inches in diam¬ eter. The shell will be stiffened by a composition angle 1 x 1 x inch, placed in such a position over the framing of the boat as to afford ready means of support for the condenser. The flanges at the ends will also be made use of for supporting the condenser, plates being run up from the framing for that purpose. 33. AIR PUMPS. There will be two double-acting horizontal air pumps worked from eccentrics on the forward end of the main shaft. Each cylinder will be 2^ inches in diameter, and the stroke of piston will be 3 inches. Both cylinders and casings will be made in one casting, as shown. The suc¬ tion nozzle will be on the inboard end of the casing above the cylinders, and will open into a suction chamber formed around the cylinder, as shown. In the center of the cyl- Y> v ' . . < . 18 inders there will be a port inch wide, extending en¬ tirely around the cylinder, connecting it directly with the suction chamber. The thickness of the piston will be such that it will just give a full port opening at each stroke. There will be no suction valves, the piston itself taking their place. The piston will be made hollow and filled with some approved water-excluding material. It will be fitted with grooves for water packing. Its ends will be flat. The cylinders will be made of such a length that the piston will come about flush with the end of the cylin¬ der at each stroke. There will be a delivery valve for each end of each cylinder. They will be made flat on the face, and not more than inch clearance will be allowed between them and the end of piston when at the end of its stroke. The inboard valve will be guided on the piston rod while the outboard will be guided by a pin cast on the cylinder bonnet, as shown. The guide stem on the valve will be at least i inch long. Both valves will be kept on their seats by conical springs of phosphor-bronze or other approved material. They will be set to produce a pressure upon each valve of about 5 pounds. The valves will be made of phosphor-bronze or equivalent metal. Ample passageways will lead from the delivery valves into the delivery chamber above. The delivery chamber will also form an ample air chamber. The delivery pipe will be so located that water will always remain over the valves, and that sufficient air will remain in the upper part of the discharge chamber to act as an efficient air chamber. There will be one bonnet for each end of the cylinders. The guides will be cast on the forward bonnet. The crosshead will be made of steel; it will be bored for the piston rod. The piston rod will be screwed into the cross¬ head and held by jamb nuts in such a way as to allow for adjusting the position of the piston as desired. Piston-rod stuffing boxes will also be placed in the inboard bonnet. The eccentric straps will be of composition lined with white metal similar to those belonging to the valve gear. ‘ . . / " in 19 The eccentrics will be of cast iron, having a throw of i]/2 inches and a diameter of 7 inches; they will have a wear¬ ing face 1 inch broad. Each connecting rod will consist of two pieces secured to the eccentric strap by two body-bound bolts. The pump will be secured to the frames of the boat in an approved manner. All parts of the pump not other¬ wise specified will be of composition. The auxiliary feed pump in the engine room will have a suction pipe and straightway valve connected with the branch to the air-pump suction, so that fresh water may be pumped out of the condenser into the boiler or tank when the main engine is standing still. 34. CIRCULATING PUMP. There will be a centrifugal pump discharging all around the periphery and face of the runner directly into the water chamber of the condenser, to which the pump casing will be bolted. The suction of the pump will be 2^4 inches in diameter, with a scoop fitted on the outside of the vessel, covered with a strainer having a combined area through the holes equal to twice the section of the injec¬ tion pipe. The outboard delivery pipe from the condenser will likewise be fitted with a scoop. There will also be a 2^4-inch suction pipe from the bilge fitted with a screw check valve. The injection pipe will have a butterfly valve for shutting off the inlet from the sea. The runner of the pump will be of composition, 7 inches in diameter, of conical shape, having eight wings cast on the disk, as shown; it must be perfectly smooth and true. The casing will be of composition ^ inch thick, with a bearing cast in it which will be lined with white metal, and be fitted with a stuffing box around the shaft. The shaft will be of 24-inch steel, covered with a brass sleeve sweated and pinned on. The runner will be secured to the shaft in such a way that no part of the steel shaft will be exposed to the action of salt water. - - . ; . . ' > 20 35. CIRCULATING-PUMP ENGINE. It will be of the vertical single-cylinder type, as shown, 2 inches in diameter by i^4-inch stroke, fitted with a slide valve. The main shaft will be of forged steel, with a thrust bearing, as shown, to run in Babbitt metal. The whole will be firmly secured to a bracket cast on the runner casing. The details of the engine will be of ap¬ proved design. 36. EEED TANKS. Two fresh-water feed tanks will be supplied, each holding about 35 gallons. One placed on the starboard side of the engine room will be made narrow enough to leave flooring about 16 inches broad along the engine, its approximate dimensions being 5 inches by 27 inches by 60 inches. The second tank will be placed against the after bulkhead in the fire room, having dimensions about 15 inches by inches by 65^4 inches. They will both be made of galvanized iron, No. 16 B. W. G., stayed and provided with screw hand-holes for cleaning. The tank in the fire room will serve as an overflow from the hot well, and will be provided with a 1-inch vapor pipe running into the forced-draft venti¬ lator overhead. A suction pipe will lead from both tanks to the main and auxiliary feed pumps, with a straightway valve in each branch. 37. SEA AND BILGE CONNECTIONS. A 1-inch connection, with straightway valves, will be made with the main injection, for putting water on the brasses in case of heating. A section of i-inch hose, of sufficient length to reach all parts of the engine and thrust bearing, will be connected to the above. A 1-inch sea suction will be provided with the auxiliary feed pump in the engine room. It will be controlled by a valve which will not allow seawater to enter the bilge or the feed tanks. Both feed pumps will have suction pipes, of the full size of their suction nozzles, to the bilge in their re¬ spective compartments. 270—4 • 1 / ' 21 There will be a steam ejector in the fire room con¬ nected directly with the bilge. It will lead through the side of the boat at the water line, and will be provided with a straightway valve in the delivery pipe. It will have a capacity of about 7 tons an hour. 38. SECURING ENGINE IN VESSEL. The engines will be adjusted and aligned upon the engine keelsons. The holding-down bolts will be firmly set up with nuts and locked nuts. All shafting must be accurately in line with the vessel at load draft and ordinary stowage. 39. ENGINE ROOM GONG. A signaling gong will be placed in the engine room, with bell pull in the pilot house. All connections must be made to minimize the chance of derangement. 40. ENGINE INDICATORS. Means will be provided for taking indicator cards from the main engine. The indicator pipes must not be less than ^2 inch in diameter, and must be fitted without short bends. The indicator motion must be coincident with the motion of the piston, and all parts must be secured in such a manner as to stand without derange¬ ment about 675 revolutions per minute. Each indicator string must have a direct lead to the barrel. 41. COMMUNICATION WITH ENGINE ROOM. A speaking tube will connect the engine room and pilot house if required. It will be made of copper, ^ inch diameter, and not less than No. 20, B. W. G. Each end will be flared out into a trumpet mouth without annunciator. A glass door, about 8 inches in diameter, will be provided in the bulkhead between the engine room and fire room. It will be hinged, with an air-tight rubber joint around the edge, and placed in such a posi¬ tion as to afford read}^ means of communication between the engine and fire rooms. - » . • > * ■ 22 42. BOILER. The boiler will be of the sectional-coil or tubulous type, of such design as may be approved by the Bureau of Steam Engineering, and of sufficient size to develop 155 indicated horse power under forced draft. Efficient means must be provided for getting at all parts of the boiler which require attention for examination, cleaning, or repairs. The manhole plates will be of cast or forged steel, in dished form, with a convenient handle for removing. The boiler will be designed for a working pressure of 250 pounds per square inch, and will have not less than 9% square feet of grate surface, and 372 square feet of heating surface. The calorimeter through the tubes will not be less than .18 of the grate surface, and the calorimeter of the uptake about \ of the grate. 43. BOILER MATERIAL. All plates and rivets used in the construction of the boiler will be open-hearth steel, subject to the test and inspection required by the steel-inspection circular for armored cruiser No. 3. The tubes will be of iron or steel, lap-welded or drawn, and equal to the best in the market. They will be sub¬ ject to the approval of the Bureau of Steam Engineer¬ ing. 44. RIVETED JOINTS. All rivet holes in plates w T ill be drilled in place after bending or shaping. The rivets will be driven by hydraulic power wherever possible. In parts where they are driven by hand, the holes will be coned, and conical rivets used. All seams in the drums may be welded. 45. GRATE BARS AND BEARERS. The grate bars will be of wrought iron of approved pattern. They will be so fitted as to be readily removed and replaced without hauling fires. The ash pan will have ample depth to prevent the grate bars burning out : •- . ’• • * : 1 - • ' . • - " . • . rf? .fijl I 23 under forced draft, or will be fitted with pans containing water. The bearers will be made of wrought iron, supported by wrought-iron lugs. 46. FURNACE FRONTS AND DOORS. The furnace fronts and doors will be of approved pat¬ tern, well protected from the heat of the fire. 47. UFTAKES. The uptakes will be made of wrought iron, stiffened with angle irons, and secured in an approved manner, according to the type of boiler adopted. There will be two thicknesses of iron, with a space of at least i inch between them filled with incombustible nonconducting material. Uptake doors will be fitted wherever neces¬ sary to clean the tubes or passageways of soot or ashes. They will be made with double shells of the same thick¬ ness as the uptake, and the space between the two thick¬ nesses fitted with the same nonconducting materials. Each door will have an eye near the outer end, for han¬ dling. 48. SMOKE PIPE. There will be one smoke pipe, extending about 12 feet 2 inches above the grate. Its diameter will be 15 inches inside, and the pipe will be double, with an air space of about i}i inches between the two thicknesses, from the junction with the uptake to the top. The lower part of the pipes will be shaped to connect with the uptakes, and will be built of No. 12, B. W. G., iron or steel; the upper part will be of No. 14, B. W. G., and the outside casing of No. 16, B. W. G., iron or steel. The two thicknesses will be stayed together, and the pipes will be stayed in place with approved guys and turn-buckles. They will also be readily removable when hoisting and stowing the boat. All joints on the outside casing will be butted and strapped with flush rivets on the outside, and the top will be finished with half-round iron or brass. ... /*(•-. f> • . f 1 » ' ' ' ■ • ■ 24 The annular air space will be open at the top and bot¬ tom for a current of air. The boiler will rest in saddles, or be secured in an ap¬ proved manner. 49. BOILER ATTACHMENTS. The boiler will have the following attachments: One dry pipe. One steam distribution casting. One main stop valve. One auxiliary stop valve. One main feed check valve. One auxiliary feed check valve. One bottom blow valve. One surface blow valve. One safety valve. One steam gauge. One glass water gauge of automatic closing type. Four gauge cocks. One or two drain cocks, according to the type of boiler. All external fittings will be of compostion unless otherwise directed. They will be flanged and through-bolted, or attached in other approved manner. The stems of all valves attached to the boilers will have outside screw threads. The internal pipe will be of brass, No. 14, B. W. G., sup¬ ported in such a manner as to touch the plates inside, only where they connect with the outside fittings. 50. DRY PIPE. If required by the Bureau of Steam Engineering, there will be, in the highest part of steam space of the boiler, a brass dry pipe of ifa inches inside diameter, and No. 14, B. W. G., extending nearly the length of the boiler. It will be perforated on the upper side with longitudinal slits, or small holes with an aggregate area of seven eighths the area of the stop valve ; and a small drain hole will be drilled at the bottom near each end. The inner end will be closed and the outer end secured to the spigot of the distribution casting by four bolts. ' . ■ • • : * ■ 25 51. STOP VALVES AND DISTRIBUTION CASTING. A composition casting with a i ^ 4 -inch branch for the dry pipe, a i^-inch branch for the main stop valve, a i %-inch branch for the safety valve, and a 24-inch branch for the auxiliary stop valve, will be bolted to the steam drum. A spigot will extend beyond the flange through the boiler head far enough to secure the dry pipe. A steam stop valve i ]/% inches diameter for the main steam pipe, and a 24-inch stop valve for the main feed pump, will be bolted to the casting. 52. FEED CHECK VALVES. The main and auxiliary check valves will be of diam¬ eter sufficient to supply the boiler. They will be secured to the fire-room end of the boiler, but entirely separate from each other. The valve cases will be so made that the bottom of the outlet nozzle will be 24 inch above the valve seat. The valves will be assisted in closing by phosphor-bronze springs. 53. BOTTOM AND SURFACE BLOW VALVES. There will be a 24 -inch bottom blow valve with an in¬ ternal pipe leading to the lowest part of the boiler, and a 24 -inch surface blow valve with an internal pipe lead¬ ing to a scum pan near the surface of the water. Both valves will be located within easy reach of the fire room. 54. SAFETY VALVE. The boiler will have one spring safety valve of i% inches diameter, secured to the nozzle on the distribu¬ tion casting. The valve will have a projecting lip and an adjustable ring for increasing the pressure on it when lifted, and for adjusting its closing pressure. It will be adjustable to forty pounds above the working pressure, and provided with a separate steel testing clamp for hold¬ ing the valve on its seat for hydrostatic test of the boiler without changing the adjustment of the spring; also, a lock will be provided to prevent tampering with the spring or valve. The spring will be square in section, of ' . 26 first quality of tool steel, and will be nickel plated. It will have spherical bearings at the ends, and will be long enough to allow the valve to lift one eighth of its diam¬ eter when loaded to 250 pounds pressure per square inch. The valve stem will fit loosely in the valve to bottom below the level of the seat, and be so secured that the valve may be turned by a wrench or cross-bar on top’of the stem. The spring will be inclosed in a case such that steam can not come in contact with it. The valve will be guided by wings below and in an approved manner above. Mechanism for lifting the valve by hand will be provided. The casing, valves, and spindle will be of composition, and the seat will be a solid nickel casting screwed into the top of the composition base. A connection will be made with the escape pipe from the side of the casing. Suitable gear will be fitted for working the safety valve from deck. 55. STEAM GAUGE. There will be one steam gauge on the boiler, equal to Lane’s improved, with seamless tubes, and 6-inch dial graduated to 350 pounds. It will have an independent connection with the boiler, and will be located where visible from the engine room. 56. BOILER WATER GAUGES. The boiler will have one glass gauge of approved auto¬ matic closing pattern. The gauge will be placed near the fire room, where it will be plainly visible from the engine room, and the pipe connections with the boiler will be at at least %-inch. The shut-off and blow-out cocks will be packed cocks, and the glass will be about 10 inches in exposed length, with the lowest exposed part 1 inch above the highest heating surface. There will be four packed gauge cocks, with independ¬ ent attachments to the boiler if possible. They will be spaced as directed. The blow-out and gauge cocks will have a drip pan and drainpipe to the bilge. 57. BOILER DRAIN COCKS. The boiler will have packed drain cocks enough to drain all parts. They will be at least % inch in diameter. 58. MAIN AND AUXILIARY FEED PUMPS. There will be one main feed pump in the fire room, and one auxiliary feed pump in the engine room, both vertical, of approved pattern. The main feed pump will have a steam cylinder 4 inches in diameter, water cylinder 2^ inches in diameter, and a stroke of 4 inches It will be connected to draw from either feed tank or from the bilge, and to deliver into the boiler or overboard. The auxil¬ iary pump will have a steam cylinder 4 inches in diameter, water cylinder 2^ inches in diameter, and a stroke of 4 inches. It will be connected to draw from either feed tank, the condenser channel way, the bilge, or the sea, and to deliver into the boiler, overboard, or to the ash hose. The main pump will take steam direct from the boiler, and the auxiliary pump direct from the main steam pipe. Both will exhaust into the auxiliary exhaust pipe. A straightway valve will be placed near the pump in every suction and delivery pipe. The pump cylinders, together with their valve boxes and fittings, will be made of composition, unless other¬ wise specified. The pistons must be packed, and all parts of cylinders and valves easily accessible for overhauling, without disturbing the piping. 59. FIRE-ROOM BLOWER AND ENGINE. There will be one blower of approved pattern in the fire room, located on the bulkhead. It must be capable of supplying to the fires continuously sufficient air to maintain a combustion of about 560 pounds of coal per hour. It will take air from a ventilator, and deliver into an air-tight fire room. All bearings must be accessible for oiling while the blower is in motion, and well pro¬ tected from the dust. The blower engine will be located on the bulkhead between the engine and fire rooms, and the shaft will pass through a composition bushing in the bulkhead. The cylinder will be similar to that for the circulating pump, and of the same dimensions. 60. AIR-PRESSURE GAUGE. A glass U, with branches about 6 inches long, will be secured to the engine-room bulkhead, with one branch . . l‘jd , 'i* ■ . , • 28 connected with the fire room. It will have about 3 inches of water in each branch, with a scale graduated to inches and tenths behind it to show the air pressure in the fire room. 61. ASH SPRINKLER. A ^-inch valve for wetting down ashes will be fitted in the fire room where directed. It will be connected with the delivery pipe of the auxiliary feed pump, and will be fitted with about eight feet of hose and the neces¬ sary coupling and nozzle. 62. STEAM TUBE CLEANER. A steam tube cleaner of approved design will be fitted. Steam will be taken from the branch to the main feed pump, and a sufficient length of steam hose to reach all the tubes will be provided. 63. MAIN STEAM PIPE. A seamless drawn-copper pipe of No. n, B. W. G., and 1J/8 inches inside diameter, will connect the stop valve on the boiler with the stop valve of the engine. It will be led as shown on the drawing, and will have branches to the blower engine, auxiliary feed pump, and circula¬ ting pump. The flanges will be of standard dimensions, of brass, and will be brazed to the pipe. 64. AUXILIARY STEAM PIPES. Branch pipes will lead from the main steam pipe as follows : ^-inch diameter to the blower engine ; }4-inch diameter to the circulating engine ; ^4-inch diameter to the auxiliary feed pump ; ^4-inch diameter to the main exhaust pipe for use as a bleeder ; ^-inch diameter to the second intermediate-pressure receiver, to be fitted with a valve to reduce pressure to 80 pounds. A ^ 4 -inch steam pipe will lead direct from the boiler to the main feed pump. A ^ 4 -inch steam pipe will lead from steam drum to the whistle. All the above pipes will be of drawn copper, and the joints will be made with flanges, brazed on. 270—5 29 A stop valve will be placed in each end of all the above pipes, except that one leading to the condenser. The diameters are measured on the inside. 65. AUXILIARY EXHAUST PIPES. A i-inch exhaust pipe will lead to the condenser and to' the escape pipe, with branches as follows: ^4-inch to the blower engine; ^4-inch to the circulating engine; ^4-inch to the auxiliary feed pump ; }4-inch to the main feed pump. All of these pipes will be of drawn copper, and the joints will be made with flanges, brazed on. A straight¬ way exhaust valve will be placed near each engine, and a i-inch straightway valve near the condenser, and also at the junction with the escape pipe. 66. ESCAPE PIPE. There will be a brass escape pipe, inches inside diameter, abaft the smoke pipe, finished and secured in an approved manner. It will lead from the safety valve to the upper end of the smoke pipe, and that part above the deck will be easily removable. 67. FEED PIPES. A seamless drawn-copper pipe, of the full size of the pump discharge, will lead from the main and auxiliary feed pumps, to the main and auxiliary feed check valves, respectively. Near each check valve there will be a straightway valve with handwheel, in a convenient posi¬ tion for regulating the feed. All parts of the pipe will be above the floors in plain view, and all joints will be made by screwed flanges. 68. SUCTION AND DISCHARGE PIPES. The pumps will have such suction and discharge con¬ nections as are required for the duty assigned to them. In all cases the pipes will be of drawn copper of the same sizes as the pump nozzles, and the joints will be made by means of flanges. All brass or copper pipes in the bilges will be tinned on the outside, well painted, and covered with waterproof canvas. They must not rest in contact 30 with any of the iron or steel work of the vessel. Bilge suction pipes will take from small strainer boxes placed in the bilge. 69. MISCELLANEOUS PIPES. Surface and bottom blow pipes of drawn copper will be fitted as directed, and such other pipes not specified as are necessary to the successful working of the machinery and boat. In all cases where brass pipes are specified they will be iron-pipe size, and all joints will be made with screwed flanges. Drainpipes will be fitted where condensed steam can accumulate. 70. PIPES THROUGH WATER-TIGHT BULKHEADS. Pipes passing through bulkheads will be made water¬ tight by stuffing boxes, flanges, or other approved method. Steam joints must not be made with the bulkhead between flanges. 71. HULL CONNECTIONS. Steel strengthening rings will be riveted to the hull plating around the opening for all outboard pipes. The boiler blow pipes and pump discharge pipes will be led above the water line, and no outboard valves will be required for any pipe except the auxiliary pump suction from the sea. The flanges will be bolted to the strength¬ ening rings by rolled manganese, or Tobin bronze studs. A zinc protecting ring will be fitted in each opening in the skin in such a manner as to be easily renewed. 72. COCKS AND VALVES. All cocks and valves, and their fittings, except where otherwise specified, will be of composition. All hand- wheels will be of finished brass, with diameters at least i times those of the valves. All cocks over i inch diameter will have packed plugs. Valves of approved pattern will be supplied wherever necessary to complete the pipe system, whether herein specified or not. All valves will be so fitted as to be 31 easily ground in. All valve spindles must turn right- handed to close, and must have outside threads when practicable. All cocks and valves below the floor plates will have their wheels or handles above the floor, in accessible positions. The sizes given refer to the diam¬ eters of the equivalent clear openings. 73. GAUGES. There will be the following gauges in polished brass cases, suitably engraved to show to what they are con¬ nected; all to be of approved pattern, and equal to Lane’s improved, with seamless tubes:— One on the boiler, graduated to 350 pounds pressure. One on the bulkhead, between engine and fire rooms, connected to the main steam pipe, graduated to 350 pounds pressure. One vacuum gauge connected to the condenser. The above will have 4%-inch dials. 74. BOLTS AND NUTS. All boltheads and nuts, except in special cases, will conform to the U. S. Navy standard. Screw threads must in all cases conform to this standard. The nuts of all bolts on moving parts and on pillow blocks will be fitted with keepers, and the bolts will extend beyond the nuts without thread, for a split pin. 75. CLOTHING AND LAGGING. The main cylinders and valve chests, after being finally secured in place in the vessel and tested, will be covered with approved incombustible nonconducting material, and neatly lagged with black walnut, with polished brass bands, and round headed brass screws. The lagging will be fitted in such a manner over the cylinders, valve chests, and cylinder heads as to be easily removed, re¬ placed, and repaired. The cylindrical part of the condenser will be clothed with approved material. All steam and exhaust pipes and all steam valves will be clothed in an approved manner with a satisfactory non¬ conducting material, covered with canvas, and painted. % ■ i' • 32 76. WHISTLE. An approved polished brass steam whistle, with bell about 2 inches in diameter, will be placed forward of the smoke pipe, near the top of the pipe. It will be connected to the auxiliary steam pipe by a pipe having a stop valve at its lower end, and a working valve at the upper end. The pipe above the deck will be easily removable, and all connections will be made in such a way that all con¬ densed water will drain back into the boiler. 77. FLOORS AND PLATFORMS. The engine room and fire room will be floored with wrought-iron plate, inch thick, with flat-topped corru¬ gations running fore and aft. The plates will be of con¬ venient size and easily removable. They will rest on proper ledges of angle or T iron, and will have drain holes where necessary. 78. LADDERS. Ladders will be fitted where necessary for reaching the fire room and engine room from deck. They will be fitted to be easily removable. 79. OIL TANK. A small oil tank of about 3 gallons capacity will be fitted where directed. It will be made of copper, and will have a drip pan large enough to hold two 1-quart feeders and a squirt can. 80. VENTILATOR. A ventilator of 10 inches internal diameter will be fitted as directed, for supplying the fire room. It will be of wrought iron No. 18, B. W. G., with a movable copper cowl of No. 18, B. W. G., not planished. The cowl will be at least 15 inches in diameter. The lower end of the ventilator will be constructed with a door to admit air direct to the fire room when running natural draft. 81. TOOLS. The following tools will be furnished :— One set of wrenches, complete, for the engine and fire rooms, to be fitted for all nuts in their respective . ... 33 compartments, plainly marked with sizes, and fitted in an iron rack in the engine room. The wrenches will be open-ended or socket, as required for the special service. Fixed trammels for setting the main valves without removing the covers, also trammels for aligning the crank shaft: all parts to be properly marked for the pur¬ pose. One complete set of fire tools for the fire room. 82. DUPLICATE PIECES. The following duplicate pieces will be furnished :— One set of valves for each pump. Two spare crank-pin brasses, complete, and fitted to all crank pins. One complete set of brasses and bushings for the main engine valve gear. One complete set of brasses for the circulating-pump engine, the blower engine, the air pump, and the feed pumps. One complete set of metallic packing for each diam¬ eter of stuffing box. One set of packing rings for each steam piston and piston valve. One complete set of grate bars and bearers, and one pattern for each casting. Such spare parts of the boiler as may be required by the Bureau of Steam Engineering after an inspection of the drawings. Thirty condenser tubes and 60 condenser-tube glands. All duplicate pieces will be marked or stamped, and well packed to prevent corrosion. All boiler tubes will be stowed in boxes. The above parts will not be regarded as part of the machinery weights, but will be delivered at such navy yard as may be directed. 83. MATERIALS AND WORKMANSHIP. All castings must be sound and true to form, and before being painted must be well cleaned of sand and scale, and all fins and roughness removed. / ; » 34 No imperfect casting or unsound forging will be used if the defect affects the strength, or to a marked degree its sightliness. All nuts on rough castings will fit facings raised above the surface, except where otherwise directed. All flanges of castings will be faced, and those coupled together will have their edges made fair with each other. The faces of all circular flanges will be grooved. All bolt holes in permanently fixed parts will be reamed or drilled fair and true in place, and the bodies of bolts finished to fit them snugly. All pipes beneath floor plates will be connected by forged bolts and nuts of rolled manganese, or Tobin bronze. All brasses will fit loosely between collars of shafting. All brasses or journals will be properly channeled for the distribution of oil. Packing for stuffing boxes will be such as may be approved. All small pins of working parts will be well case-hard¬ ened. All steel joint pins of valve gear will be hardened and ground to true cylindrical surfaces. All materials used in the construction of the machinery will be of the best quality. The iron castings will be made of the best pig iron, not scrap, except where otherwise directed. Composition castings will be made of new materials. The various compositions will be by weight as follows :— For all journal boxes and guide gibs: Copper 6, tin i, and zinc % parts. Naval brass : Copper 62, tin 1, and zinc 37 per cent. For composition not otherwise specified : Copper 88, tin 10, and zinc 2 per cent. Muntz metal will be of the best commercial quality. Antifriction metal will be of approved kind. Ornamental brass fitting will be of good uniform color. All castings will be increased in thickness around core holes. Core holes will be tapped, and core plugs screwed in and locked, except where bolted cores are used, or where it may be directed that the holes be left open. • 35 All steel forgings will be without welds and free from laminations. All flanges, collars, and offsets, will have well-rounded fillets. All boiler plates, stays, and tubes, will be well cleaned of mill scale by pickling, or other approved means. All flanged parts of boilers will be annealed after flanging, in an approved manner. India-rubber valves will be of approved kind, of best commercial quality. All bolts for securing the boiler attachments will, where possible, be screwed through the boiler plates, with heads inside. All work will be in every respect of the first quality, and executed in a workmanlike and substantial manner. Any portion of the work, whether partially or entirely completed, found defective, must be removed and satis¬ factorily replaced without extra charge. 84. TESTS OF MATERIAL. All steel used in the construction of the boilers, and all steel forgings and castings, will be tested in accord¬ ance with rules prescribed by the Navy Department. All condenser tubes will be tested to 300 pounds pres¬ sure per square inch, applied internally before being put in place. India rubber valves, taken at random, must stand a dry-heat test of 270 0 for one hour, and a moist-heat test of 400 0 for three hours, without injury. 85. TESTS OF BOILERS AND MACHINERY. Before the boilers are painted or placed in the vessel, they will be tested under a pressure of 340 pounds to the square inch above atmospheric pressure. This pressure will be obtained by the application of heat to water within the boilers, the water filling the boilers quite full. The steam pipes and valves, the auxiliary engines, and all fittings and connections subjected to the boiler pres¬ sure, will be tested by water pressure to 340 pounds to the square inch. 36 The high-pressure cylinder and valve chests will be tested by water pressure to 340 pounds to the square inch; the first intermediate-pressure cylinder and con¬ nections to 250 pounds; the second intermediate-pressure to 175 pounds; and the low-pressure to 100 pounds. The exhaust side of the low-pressure valve chests will be tested to 30 pounds. The condensers will be tested to 30 pounds. The pumps, valve boxes, and air vessels of the feed, fire, and bilge pumps, will be tested to 350 pounds per square inch. The cylinders and condensers will be tested before being placed on board, and must be so placed that all parts may be accessible for examination by the inspector, during the tests. All parts will also be tested after being secured on board. No lagging or covering is to be on the cylinders or condensers during the tests. 86. PAINTING. After a satisfactory test, the boiler covering will be painted on the outside with two coats of brown zinc and oil, and when in place the fronts will be painted with one coat of black paint. All engine work, not finished, will be primed with two coats of brown zinc and oil; and when placed in position on board the vessel, will be painted with two coats of paint of approved color. The shafting, when in place, will be painted with two coats of red lead and oil, and two coats of black paint. The smoke pipe will be thoroughly painted before and after erection on board. The ventilators and cowls will be painted similarly to the smoke pipes, except the interiors of the cowls, which will be painted vermilion. All pipes will be painted in accordance with a schedule to be hereafter furnished. 87. PRELIMINARY TESTS AND TRIALS. Steam will not be raised in the boilers until after the water test on board, unless desired for drying or testing 270—6 37 joints, for which purpose the pressure must not exceed io pounds per square inch. After testing, steam will be raised in the boilers when- * ever required to test the connections and the workings of all parts of main and auxiliary engines. All expense of such preliminary tests will be borne by the contractor. 88. RECORD OF WEIGHTS. All finished machinery, boilers, and appurtenances thereof, as fitted, and all spare machinery and tools herein specified, will be weighed by the contractor in the pres¬ ence of the superintending naval engineer, before being placed on board, and no part of the material will be placed on board without being so weighed to the satis¬ faction of the superintending naval engineer. 89. WORKING DRAWINGS. All drawings necessary for the prosecution of the work must be prepared by and at the expense of the contractor. Those which are developments of the drawings furnished, and of these specifications, will be subject to the approval of the superintending naval engineer, before the material is ordered or the work commenced. In the drawings furnished figured dimensions, where given, will be followed, and not scaled dimensions, unless otherwise directed. All discrepancies discovered in drawings, or between drawings and specifications, will be referred to the Bureau of Steam Engineering. A copy of each working drawing will be furnished to the superintending naval engineer, before the work shown by the drawing is commenced. A copy of each drawing, accompanying orders for steel castings or forgings, will also be supplied when the work is ordered. 90. DRAWINGS OF COMPLETED MACHINERY. The contractor will make, and furnish to the Bureau of Steam Engineering, through the superintending naval engineer, a complete set of drawings of the boilers, ma¬ chinery, and appurtenances, as actually completed, includ¬ ing plans of the same as fitted on board the vessel. These * • . . 38 drawings will include every piece of machinery, both in whole and in part, and will be in such detail as would enable the entire machinery to be duplicated without additional drawings. No sheet will contain drawings of more than one part of the machinery, except those inti¬ mately connected with each other. The detail drawing of each part of the machinery will be furnished within one month after the completion of the part, without waiting for its incorporation into the machine as a whole. Detail drawings will be made to a scale of not less than 3 inches to the foot. General plans of the machinery in place in the vessel, and pipe plans, will be made to a scale of 1 inch to the foot. The pipe plans will be divided into at least two parts—one showing steam and exhaust pipes, and the other showing all other pipes. The pipe plans will be colored, in accordance with a schedule to be furnished, to indicate the purpose which the pipes are intended to serve, and will be accompanied by an explanatory index. All drawings will be made on the best quality of tra¬ cing cloth, all sheets being, as far as possible, multiples or submultiples of “double elephant” size. Detail drawings will be hatched, where in section, in accordance with a schedule to be furnished, to show the various metals employed. 91. CHANGES IN PLANS AND SPECIFICATIONS. The contractor will make no changes in the plans or specifications without the approval of the Naval Depart¬ ment. In case it is thought advisable to make changes, the contractor will make application by letter to the Bu¬ reau of Steam Engineering, through the superintending naval engineer, stating the nature of the change, and accompanied by complete plans and specifications of the proposed change, together with a statement of his estimate of the amount of increase or decrease in cost. 92. INSPECTION. The work of construction of the boilers, machinery, and appurtenances, shall be at all times open to inspec- . J •• • ' ■ 1 . * . < . 39 tion by officers appointed for such purpose by the Navy Department; every facility will be affordedsuchinspectors for the prosecution of their work. All handling of ma¬ terial necessary for purposes of inspection will be done at the expense of the contractor. All test specimens, nec¬ essary for the determination of the strength of material used, will be prepared and tested at the expense of the contractor. O , UNIVERSITY OF ILLINOIS-URBANA r 3 0112 07020834Q_ J