TS 
 
 2Z7 
 
 9XY-ACETYLENE 
 .DING AND CUTTING 
 
 BY 
 
 P. F. WILLIS 
 
GIFT OF 
 
 Mrs. 14 .T 
 
A 
 
 PRACTICAL MANUAL 
 
 OF 
 
 OXY-ACETYLENE 
 WELDING 
 
 AND 
 
 GUTTING 
 
 WITH A TREATISE ON ACETYLENE 
 AND 
 
 By P. F. WILLIS 
 
 SAINT LOUIS, MO., U. S. A. 
 
r, 1917 
 
 i c i . 
 
 BY P. F. WILLIS 
 
 ? 
 
 
 
 ^.-^llinl 
 
PREFACE 
 
 Some ten years ago, the author started 
 a welding shop, using the oxy-acetylene 
 process. He hardly knew how to light the 
 torch, much less its operation. In this 
 respect he was on an equal footing with 
 a few other venturesome individuals in 
 this country who had embarked in the same 
 business, regarding which practically noth- 
 ing was known. It follows that there were 
 many failures and disappointments. 
 
 The author can well testify that " there 
 is no royal road to learning," and yet in 
 offering this treatise he is prompted by 
 the belief that the man who goes ahead 
 may smooth out some of the rough spots, 
 and thereby assist those who come after. 
 The book is sold at a price which precludes 
 the possibility of profit to the author. You 
 pay only for the printing and the paper 
 the subject-matter is gratis. Do not look 
 a gift horse in the mouth too closely. 
 
 P. F. WILLIS. 
 St. Louis, Mo., 
 January, 1917. 
 
 468997 
 
CONTENTS 
 
 CHAPTER I. 
 ACETYLENE. 
 
 History of. Generation. Hazard. Cost. Compressed 
 or Dissolved. Market Price. Disadvantages of 
 Compressed and Generated Gas. Properties. .7-26 
 
 CHAPTER II. 
 OXYGEN. 
 
 Properties. Various Methods of Manufacture with 
 Description of each. Effect of Temperature on 
 Compressed Gas. How to Determine Contents of 
 Cylinder under Pressure with Table for same. 
 Effect of Impurities in Gas 27-42 
 
 CHAPTER III. 
 WELDING AND CUTTING TORCH. 
 
 Requisites for Welding Torch. Difficulties in 
 Manufacture. Plash-backs. Waste of Oxygen. 
 Different Types of Torches. Opinions of Author- 
 ities. Chemical Changes Taking Place in Oxy- 
 acetylene Flame. Objections to Some Torches. 
 Operation of Cutting Torch. Theoretical Amount 
 of Oxygen Necessary for Cutting. Effect on the 
 Steel 43-63 
 
 CHAPTER IV. 
 APPARATUS AND INSTALLATION. 
 
 Regulators. Construction and Care. Gauges. 
 Goggles. Acetylene Generator. Important Con- 
 siderations. Portable Generators. Directions 
 for Connecting up Tank and Generator Plant. .64-83 
 
CONTENTS. 
 
 CHAPTER V. 
 
 PREPARING FOR WELDING. 
 
 Tools Necessary for Repair Welding. Cleaning the 
 Metal. Beveling. Pre-heating Methods and De- 
 vices. Expansion and Contraction. Melting 
 Points of Metals. Regulation of Flame. Exe- 
 cution of a Weld 84-102 
 
 CHAPTER VI. 
 WELDING OF DIFFERENT METALS. 
 
 Welding of Cast-iron, Steel, Brass or Bronze, Cop- 
 per, Aluminum, Malleable Iron, and Lead Burn- 
 ing 103-120 
 
 CHAPTER VII. 
 WELDING OF SHEET METAL AND PIPE. 
 
 Sheet Metal Welding. Various Kinds of Welds. 
 Machine Welding of Sheet Metal. Welding of 
 Gas, Ammonia, Air, Steam and Water Pipes. 
 Tests and Costs of Same. Illustrations of 
 Work 121-139 
 
 CHAPTER VIII 
 WELDING OF VARIOUS PIECES. 
 
 Welding of Boilers, Automobile Cylinder, Lug on 
 Manifold, Scored Cylinder, Arm on Aluminum 
 Crank Case, Crack in Aluminum Oil Pan, Fly- 
 wheel, Large Cylinders, Crank Shaft, Partitions 
 in Oil Tank Wagons, Dies, High Carbon to Low 
 Carbon Steel, Manganese Steel, Use of Aluminum 
 Solder, Oxygen for Removing Carbon. Cost-Card. 
 Receipt Ticket. Description of Welded Castings. 
 Useful Information 1 40-1 80 
 
OXY-ACETYLENE WELDING 
 AND GUTTING. 
 
 CHAPTER I. 
 
 ACETYLENE. 
 
 What is Acetylene? 
 
 A hydro carbon gas composed of equal 
 volumes of carbon and hydrogen. By 
 weight it is composed of 93% carbon and 
 7% hydrogen. 
 When was it discovered? 
 
 In 1836 by Davy, an English chemist, 
 and Berzelius, a Swiss chemist. 
 From what is Acetylene obtained? 
 
 From calcium carbide. 
 What is Calcium Carbide? 
 
 It is a substance, hard like rock, of a 
 grayish color, and possessing a slight crys- 
 talline structure. 
 When ivas it discovered? 
 
 In 1892 by an American chemist, named 
 Willson, at 'Spray, N. C. 
 How is it manufactured? 
 
 Lime and coke in the proportion of 56 
 parts by weight of the former to 36 parts 
 of the latter are fused or melted together 
 in an electric furnace. It is cooled and 
 
8 ; pilY-AC^Tyi^E^^ vVELDING & CUTTING. 
 
 , and; i: :then assorted as to size 
 by iiieaiig of screens. 
 
 How is Acetylene obtained from Calcium 
 
 Carbide? 
 When calcium carbide and water are 
 
 brought together, acetylene is formed. This 
 
 is accomplished as follows: 
 
 The calcium in the calcium carbide 
 combines with some of the oxygen in the 
 water and forms first calcium oxide 
 or quick lime, and then calcium hydroxide 
 (slacked lime). The carbon in the calci- 
 um carbide combines with some hydro- 
 gen from the water to form acetylene, 
 the chemical symbol of which is C 2 H 2 . 
 
 Is there more than one method of bringing 
 
 the Carbide and water together 
 Yes, there are three methods. 
 
 Name them. 
 
 First, water to carbide; second, reces- 
 sion ; third, carbide to water. 
 
 Explain each method. 
 
 The "water to carbide" method consists 
 in allowing water, drop by drop, to fall 
 upon a body of carbide. This was the 
 earliest method of generating acetylene 
 and its adoption was due to the fact that 
 it was easier to control the flow of water 
 than it was the feeding of the carbide; 
 
ACETYLENE. 
 
 especially as the carbide first put on the 
 market was not uniform as to size. 
 
 The "recession" method consists in al- 
 lowing water to rise, coming in contact with 
 either a mass of carbide or successive lay- 
 ers of carbide. 
 
 The "carbide to water" method consists 
 in feeding the carbide in small amounts 
 into a large volume of water. 
 
 Which is the best? 
 
 The "carbide to water." 
 
 *rr - ~ !'.' "-;'' *' 
 
 Why? 
 
 After generation is impossible and purer 
 gas is produced. Again when carbide and 
 water are brought together heat is evolved. 
 
 Now this heat can be considerable, some- 
 times reaching 1000 F., or it can be negli- 
 gible, depending entirely upon the amount 
 of water. If there is a sufficient amount 
 of water both the carbide and the water 
 will be kept cool. It has been found that 
 if for each pound of carbide, one gallon 
 of water is supplied, the temperature is 
 kept down in fact, cannot possibly exceed 
 212 F., and in practice never goes that 
 high. The "carbide to water" method is 
 the only one that guarantees a sufficient 
 amount of water to assure cool generation. 
 
10 OXY-ACETYLENE WELDING & CUTTING. 
 
 What effect does heat have on Acetylene 
 during generation 
 
 If the heat should rise high enough, what 
 chemists term polymerization takes place. 
 By this is meant that the acetylene under- 
 goes a change and is transformed into 
 other gases, such as benzol, styrolene, etc. 
 These latter gases require for their com- 
 bustion a different amount of oxygen than 
 does acetylene, and their flame temperature 
 is not so high. 
 
 A temperature that would produce pol- 
 ymerization, would also be hazardous, and 
 if there was any mixture of air with the 
 gas, an explosion would likely result. 
 Is it possible Jo explode Acetylene? 
 
 Yes. 
 How? 
 
 First, when mixed with air in the proper 
 proportions 3% to 58% of acetylene to 
 the rest air and in the presence of a spark 
 or flame. 
 
 Second, at a pressure of 24 pounds it is 
 possible for it to explode without any air 
 mixture, in the presence of spark or flame. 
 
 Third, when compressed in an ordinary 
 container to 30 pounds or more it may ex- 
 plode without any air mixture and without 
 a spark or flame. Neither concussion or 
 shock are necessary to produce the explo- 
 sion. An explosion of this character is 
 
ACETYLENE. 11 
 
 generally attributed to decomposition, 
 although some claim that it is due to im- 
 purities in the carbide, such as sulphur and 
 phosphorus forming combinations which 
 ignite spontaneously. 
 
 Is it possible to compress Acetylene to 25 
 
 pounds or higher safely? 
 Yes. 
 
 Howf 
 
 The container is first filled with a porous 
 substance, such as asbestos cement. It is 
 then further filled with an inflammable 
 liquid called acetone. This liquid, acetone, 
 has been found to possess the peculiar 
 quality of dissolving or absorbing 25 times 
 its volume of acetylene at atmospheric 
 pressure and continues to do this for each 
 atmosphere of pressure (15 pounds) it is 
 put under. 
 
 While the asbestos cement apparently 
 fills the tank, in reality, on account of its 
 porosity, only 20% of the space in the tank 
 is occupied by the asbestos; acetone to the 
 amount of about 43% of the capacity of 
 the tank is then added. This leaves about 
 37% of the contents of the tank for acety- 
 lene as it is taken up or dissolved by the 
 acetone. This absorbing or dissolving qual- 
 ity of the acetone is so remarkable that 
 it may be well to compare the amount of 
 
12 OXY-ACETYLENE WELDING & CUTTING. 
 
 acetylene that a tank of one cubic foot 
 capacity would contain under fifteen at- 
 mospheres (225 pounds) and the amount 
 the same size tank will contain under the 
 same pressure but with the gas dissolved. 
 In the first instance there will be approxi- 
 
 Fig. 1. 
 Commercial Acetylene Co.'s Tank. 
 
 mately fifteen cubic feet of gas. We sim- 
 ply multiply the cubic contents (one foot) 
 by the number of atmospheres (fifteen). 
 In the latter, however, there will be about 
 
ACETYLENE. 13 
 
 161 cubic feet or roughly estimated at 
 about ten times as much gas as in the first 
 tank. This is obtained as follows: 
 
 The amount of acetone is about 43% of 
 the contents of the tank whose capacity 
 was assumed to be one cubic foot. There- 
 fore, the acetone occupies .43 of a cubic 
 foot. At atmospheric pressure the acety- 
 lene dissolves twenty-five times its volume 
 of acetylene, so that in this case at zero 
 gauge pressure there is in the tank .43x25 
 or 10.75 cubic feet of acetylene and at 225 
 pounds pressure there will be 10.75x15 or 
 161 cubic feet. 
 
 Docs Acetylene exercise a toxic action if 
 air containing a large proportion of it 
 is breathed? 
 
 The best authorities agree that acetylene 
 itself possesses very small poisonous qual- 
 ities, so that the danger of breathing it is 
 practically nil. This is because it is almost 
 free of carbon monoxide. 
 
 Hoiv much Acetylene will a pound of car- 
 bide produce when made ivith a gen- 
 erator? 
 
 Conservatively 4^2 cubic feet for the 
 lump size and 4^ cubic feet for the very 
 small size. One carbide manufacturer 
 claims five cubic feet and another 4.8 cubic 
 feet, but their figures cannot be obtained. 
 
14 OXY-ACETYLENE WELDING & CUTTING. 
 
 What is the present price of carbide? 
 
 Three and three-fourth cents per pound 
 without a contract ; from S 1 ^ to S^c per 
 pound with a contract, according to con- 
 sumption. 
 
 What is the cost of Acetylene per cubic 
 foot made from a generator at above 
 prices for carbide? 
 
 Not to exceed 8/10 of a cent per cubic 
 foot or 80c per 100 cubic feet. 
 What is the price of dissolved or com- 
 pressed Acetylene? 
 
 From $1.80 per 100 cubic feet to large 
 users to $2.15 per 100 cubic feet to the 
 average consumer plus freight on the full 
 tank and on the empty tank returned. 
 Taking into consideration the freight, what 
 is the average cost of "tanked" 
 Acetylene? 
 Two and one-half cents per cubic foot. 
 
 What size or capacity of Acetylene tank 
 
 should be used for welding 
 Under no circumstances should a tank 
 of less capacity than 100 cubic feet be used. 
 A tank should not be discharged at a faster 
 rate than one-seventh of its capacity per 
 hour. This means that a welding tip should 
 not be used on a 100-cubic foot tank if it 
 consumes more than 15 cubic feet per hour. 
 The use of small automobile tanks should 
 
ACETYLENE. 15 
 
 be discouraged, only the very lightest work 
 can be done and the cost of the gas is con- 
 siderably more than it is when using the 
 regular welding cylinder. 
 When would you advise the use of 
 
 "tanked" Acetylene? 
 When only occasional welding or cutting 
 is done or where portability is desired. 
 When would you advise the use of a gen- 
 erator^ 
 
 When stationary welding or cutting is 
 done, using about 200 cubic feet of acety- 
 lene or more per week. 
 What is the saving over tanked Acetylene 
 
 per 100 cubic feet? 
 
 The difference between 80c for generator 
 gas and $2.50 for tanked gas, or $1.70. 
 Has the tanked gas any disadvantages? 
 
 Yes. 
 Name them. 
 
 (1) Inconvenience and delay in shipping 
 tanks. 
 
 (2) No assurance that you receive full 
 amount of gas in tank. 
 
 (3) Some gas always remains in the 
 tank. 
 
 (4) The solvent (acetone) mixes with 
 the acetylene and produces a bad weld. 
 
 (5) Certain make of tank not your prop- 
 erty. 
 
16 OXY-ACETYLENE WELDING & CUTTING. 
 
 (6) Likelihood of leakage from tank 
 greater than from generator on account of 
 higher pressure. 
 
 (7) Lack of sufficient gas to finish a job. 
 
 (8) Hazard. 
 
 Explain each of the above. 
 
 INCONVENIENCE AND DELAY IN 
 SHIPPING TANKS. 
 
 The inconvenience and delay incident to 
 shipping tanked acetylene is a serious 
 problem. Delays in shipment will neces- 
 sarily occur, and they usually occur when 
 the welding plant is most needed. But, 
 with the very best possible time, it is usu- 
 ally two or three days before a full tank is 
 received. One of the important values of 
 a welding plant is readiness to serve. Any- 
 one familiar with custom welding realizes 
 that 75% of the repair work must be gotten 
 out in a hurry. It is rush work, and your 
 value to the customer increases when you 
 are in a position to at all times take care 
 of the work promptly. 
 
 NO ASSURANCE THAT YOU RECEIVE FULL 
 AMOUNT OF GAS IN TANK. 
 
 With tanked acetylene you must depend 
 upon the correctness of the companies re- 
 charging the cylinders. A gauge on the 
 tank will only indicate the pressure of the 
 gas not the quantity of gas. No one but 
 
 <^ 
 
ACETYLENE. 17 
 
 the recharging people can tell how much 
 gas is in a cylinder as the amount of gas 
 depends not only upon the size of tank and 
 the pressure, but also upon the quantity 
 and quality of the solvent 'acetone in the 
 tank. It takes a smart man that can look 
 through a steel tank and tell how much 
 acetone is on the inside, and there is no 
 way for the customer to measure it. No 
 one questions the honesty' of any of the 
 firms engaged in the filling of acetylene 
 tanks, but their employees are human ; they 
 are likely to make mistakes; and as a 
 matter of fact they do sometimes make 
 mistakes. 
 
 SOME GAS ALWAYS REMAINS IN THE TANK. 
 
 With tanked gas you never get all the 
 gas out of the tank. A quite considerable 
 amount of gas remains and is shipped back 
 to the recharging station to be resold to you 
 in your next tank. 
 
 THE SOLVENT (ACETONE) MIXES WITH THE 
 
 ACETYLENE AND PRODUCES' 
 
 A BAD WELD. 
 
 When tanked acetylene is used, the gas 
 from a full tank will produce an excellent 
 weld, but as the pressure and the amount 
 of gas in the tank is lowered, the acetone 
 or solvent comes off also, adulterating the 
 acetylene, contaminating it with a hydro- 
 
18 OXY-ACETYLENE WELDING & CUTTING. 
 
 carbon of less heat units and consequently 
 lowering the temperature of the flame. This 
 acetone also contains impurities which af- 
 fect the strength of the weld. That the 
 acetone is carried off and burned with the 
 acetylene is evidenced by the fact that one 
 of the refilling companies at one time made 
 a charge of 2c per ounce for whatever loss 
 of acetone was shown when the tank was 
 returned. 
 
 A CERTAIN MAKE OF TANK NOT YOUR 
 PROPERTY. 
 
 Acetylene tanks are simply loaned by one 
 of the different concerns compressing 
 acetylene under a "Service Agreement," 
 for which they charge, and you are com- 
 pelled by the agreement to get your re- 
 charges from them. You do not own the 
 tank. It is not even leased to you. You 
 simply pay a certain amount for the privi- 
 lege of buying their gas and you cannot go 
 into the open market and buy your acety- 
 lene. 
 
 LIKELIHOOD OF LEAKAGE FROM TANK 
 
 GREATER THAN FROM GENERATOR ON 
 
 ACCOUNT OF HIGH PRESSURE. 
 
 The pressure of the gas in the high pres- 
 sure generator cannot exceed 15 pounds. 
 The pressure of the gas in an acetylene 
 tank is at least 225 pounds, and maybe 
 more. It must be obvious that the likeli- 
 
ACETYLENE. 19 
 
 hood of leakage is greater under the higher 
 pressure. 
 
 LACK OF SUFFICIENT GAS TO FINISH A JOB. 
 
 It often occurs that a welding job comes 
 in which will take a fair amount of gas. 
 Perhaps a part of the gas in your tank has 
 been used on other work and not enough 
 remains to do this particular job. What 
 are you going to do! You can use what 
 gas is in the tank to partially weld the cast- 
 ing, then send your empty tank in and 
 write or wire for another full one. This 
 means that the casting cools down and you 
 have lost your heat, which cost money ; be- 
 sides, distortion often occurs on account 
 of this cooling when only partially welded. 
 You could send the partially full tank back 
 at once and order a full tank, but this 
 means loss of gas in the tank returned. 
 
 HAZARD. 
 
 Any power-producing agency has inher- 
 ent hazards, and acetylene is no exception. 
 A generator of good design and workman- 
 ship possesses no greater hazards than a 
 compressed or dissolved acetylene tank. 
 Some tanks have exploded; so have some 
 generators ; so that any claims to the con- 
 trary, it is a stand-off between the two on 
 the question of hazard. 
 
20 OXY-ACETYLENE WELDING & CUTTING. 
 
 What are the disadvantages of a gen- 
 erator? 
 
 First, there is a slight variance in pres- 
 sure of the gas between locking and releas- 
 ing the motor. This necessitates occasional 
 adjustment of the flame by means of the 
 torch cocks. This is largely overcome by 
 means of a special regulator. 
 
 Second, recharging the generator and re- 
 moval of sludge requires about twenty 
 minutes. The indolent may offer this as 
 an objection. 
 
 Third, cost of generator is much more 
 than cost of a tank. 
 
 Fourth, some precautions must be taken 
 to prevent freezing in winter. 
 
 Fifth, generators should not be moved 
 when filled with carbide, and used for port- 
 able work. 
 
 Sixth, generator house should be pro- 
 vided, which necessitates an expense. 
 
 What fuel gas is best adapted for welding? 
 
 Acetylene. 
 Why? 
 
 The temperature of an acetylene flame 
 when burned with oxygen is in excess of 
 6300 F. This is a temperature exceeding 
 by over 2000 F. its nearest rival, hydro- 
 gen. It is the flame temperature that 
 
ACETYLENE. 21 
 
 counts in welding and not the B. T. U. 's of 
 
 What are some of the gases that have at 
 various times tried to compete with 
 Acetylene? 
 
 Hydrogen, Blau gas, Wolf gas, thermo- 
 lene, oxy-carbo, etc. 
 
 What are the objections to the above? 
 
 First, it is impossible to do heavy weld- 
 ing unless these gases are enriched with 
 acetylene. 
 
 Second, usually, the cost of doing such 
 work as is practical, is more than it would 
 cost using actylene when all factors, such 
 as labor, are considered. 
 
 Why does Acetylene, when burned with 
 oxygen, give us the hottest fuel flame 
 knownf 
 
 Broadly speaking, the gas which has the 
 greatest amount of carbon and the least 
 amount of hydrogen will give us the hot- 
 test flame. Acetylene contains by weight 
 93% carbon, almost approaching gaseous 
 carbon. There is another property which 
 acetylene possesses, which assists in in- 
 creasing the flame temperature and it is 
 the fact that it is an endothermic com- 
 pound. 
 
22 OXY-ACETYLENE WELDING & CUTTING. 
 
 What is meant by an Endo thermic Com- 
 pound? 
 
 It is a compound whose formation from 
 elementary substances is attended with ab- 
 sorption of heat. The electric furnace has 
 made the manufacture of carbide practicable. 
 Authorities differ as to whether calcium 
 carbide, when formed, absorbs or liberates 
 heat, but they are agreed that when car- 
 bide and water are brought together slacked 
 lime and acetylene are formed and that the 
 former liberates heat, while the acetylene 
 absorbs heat. When the acetylene is 
 burned, this absorbed 'or stored-up heat is 
 liberated, and helps to increase the flame 
 temperature. 
 
 What is it that limits the temperature of 
 the Oxy-Acetylene flame? 
 
 The dissociation point of carbon mon- 
 oxide (C.O.). 
 
 What is meant by the dissociation point 
 of an inflammable gas? 
 
 It is the temperature at which the gas re- 
 fuses to unite with oxygen. 
 At what pressure does Acetylene liquefy? 
 
 At 26 Atmospheres (2821bs.) At 32 Degrees F. 
 At 40 Atmospheres (588 Ibs.) At 70 Degrees F. 
 
 What is Cppper Acetylide? 
 
 It is a compound which is formed when 
 acetylene is exposed for a considerable 
 V time to copper. 
 
ACETYLENE. 23 
 
 / What properties, if any, does this com- 
 
 pound possess? 
 ^ Iti 
 
 is explosive. 
 
 What lesson do we learn from this? 
 
 That under 110 condition should copper 
 be used when it will come in contact with 
 acetylene. 
 
 What is the density or specific gravity of 
 
 Acetylene? 
 
 Assuming air to be unity or 1, it is .91 
 for acetylene. It is therefore slightly 
 lighter than air. 
 
 Does Acetylene, ivhen burned, give off any 
 
 Ultra Violet Rays? 
 
 It does not, so that no harm can come to 
 the eyes from this score. However, it must 
 be remembered that any bright light will 
 in time tire and weaken the eyes so that 
 it is strongly recommended that smoked 
 glasses be worn. 
 
 What is the weight of a cubic foot of Acety- 
 lene? 
 .069 of a pound. 
 
 How many cubic feet of Acetylene does it 
 
 take to weigh a pound? 
 14.5 cubic feet. 
 
 What is the ignition temperature of a mix- 
 
 liire of Acetylene and air? 
 About 805 F, 
 
24 OXY-ACETYLENE WELDING & CUTTING. 
 
 What concerns manufacture Carbide? 
 American Carbolite Company. 
 Canadian Carbide Company. 
 Union Carbide Company. 
 
 What companies furnish compressed 
 
 Acetylene? 
 
 Commercial Acetylene Welding Com- 
 pany. 
 
 Prest-0-Lite Company. 
 
 Searchlight Company. 
 
 What is the policy of each company ivith 
 reference to furnishing the gas? 
 
 The Commercial Acetylene Company sel- 
 dom sell any of their tanks. They usually 
 loan them to responsible people without 
 charge. They furnish tanks having a ca- 
 pacity of 125 cubic feet, 250 cubic feet and 
 500 cubic feet. 
 
 The Prest-0-Lite Company manufac- 
 tures two sizes of tanks, one of which con- 
 tains practically 100 cubic feet of gas and 
 the other 300 cubic feet. They charge un- 
 der a service agreement $20.00 for the small 
 size, and $40.00 for the large size tank. 
 
 The Searchlight people charge $30.00 for 
 the small tank, and $60.00 for the large 
 tank. 
 
 Each of these companies will refill only 
 their own tanks. 
 
ACETYLENE. 25 
 
 Which compressed Acetylene companies of- 
 fer the best proposition to the user? 
 
 The Commercial Company is the only 
 one of the three who furnish the tanks free. 
 
 The reader can judge for himself as to 
 whether he would prefer to pay for the 
 tanks or simply have them loaned. It must 
 be remembered that service is a very im- 
 portant consideration, and in some cases 
 it is advisable to purchase the tanks in 
 order to get prompt delivery. 
 
 Are there any hazards in connection with 
 
 Acetylene? 
 
 There are some who believe in minimiz- 
 ing the hazards in connection with acety- 
 lene. The writer does not belong to that 
 school. Any sensible man realizes that any 
 power-producing agency, whether it be 
 steam, electricity, gasoline or acetylene 
 holds within itself possibilities for good or 
 evil. It would seem that one way of avoid- 
 ing accidents with acetylene is to apprise 
 and thoroughly familiarize one's self with 
 its properties. When properly handled, 
 acetylene will unite in a molten mass, a 6x6 
 inch iron beam, and the same power which 
 accomplishes this wonder of yesterday will 
 play havoc if one becomes careless and re- 
 fuses to follow a very few simple and com- 
 mon sense rules. Millions upon millions 
 
26 OXY-ACETYLENE WELDING & CUTTING. 
 
 of feet of acetylene, both tanked and gen- 
 erated, are used yearly with but a trifling 
 number of accidents as compared with the 
 installations. 
 
 A few acetylene tanks and generators 
 have exploded. Where the explosion oc- 
 curred inside the generator, it was seldom 
 of a serious character. Where considerable 
 damage results it is usually caused by the 
 gas leaking out in considerable quantities 
 in the room from the tank or the generator 
 and mixing with the air. Never under any 
 circumstances try to find a leak with a 
 lighted match. Elsewhere we will advise 
 more fully as to the care that should be 
 observed when working with acetylene. 
 
CHAPTER II. 
 
 OXYGEN. 
 
 What is Oxygen? 
 
 Oxygen is an element. It is the most 
 abundant and most widely distributed of 
 all the elements, constituting by weight 
 more than one-fifth the air, and eighth- 
 ninths of all the water on the globe. It 
 enters largely into the solid constituents of 
 the earth's crust, and is found "in the tis- 
 sues and fluids of all forms of animal and 
 vegetable life. 
 
 Oxygen is a colorless, tasteless gas and 
 is essential to the support of all animal 
 life. 
 
 What is the density or specific gravity of 
 Oxygen? 
 
 Assuming air to be unity or 1, it is 1.105 
 for oxygen. It is, therefore, slightly 
 heavier than air. 
 
 How many cubic feet of Oxygen does it 
 take to make a pound? 
 
 11.209 cubic feet. 
 What does a cubic foot of Oxygen iveigh? 
 
 .08921 of a pound or 100 cubic feet 
 weighs 8.92 pounds. 
 
 What are some of the various methods of 
 making or procuring Oxygen? 
 
 (1) Red oxide of mercury. 
 
 - 27 
 
28 OXY-ACETYLENE WELDING & CUTTING. 
 
 (2) Sodium peroxide. 
 
 (3) Chlorate process, with either po- 
 tassium chlorate or sodium chlorate. 
 
 (4) Erin's process or the use of barium 
 oxide. 
 
 (5) Lavoisite process. 
 
 (6) Electrolysis of water. 
 
 (7) Liquid Air. 
 
 Describe each? 
 
 Oxygen can be obtained by heating red 
 oxide of mercury. This is purely a lab- 
 oratory experiment, not being commercial- 
 ly practical. Its only interest lies in the 
 fact that this method was the first one em- 
 ployed to produce oxygen. 
 
 SODIUM PEROXIDE PROCESS. 
 
 Sodium peroxide is a yellow solid which 
 when brought in contact with water liber- 
 ates oxygen. This process is extremely 
 simple. Each pound of sodium peroxide 
 will produce two cubic feet of oxygen of 
 high purity. The market price of the chem- 
 ical is high so that the cost of oxygen by 
 this method is excessive, ranging from 
 about 12 to 20 cents per cubic foot. This 
 method is employed to some extent in pro- 
 curing oxygen for medicinal purposes, 
 used mainly in conjunction with nitrous 
 oxide (laughing gas) as an anaesthetic. 
 
OXYGEN. 29 
 
 CHLORATE PROCESS. 
 
 Potassium chlorate when heated alone 
 to a temperature of about 350 F. gives 
 off oxygen. It has been found that if man- 
 ganese dioxide is mixed with the potas- 
 sium chlorate in the proportion of about 
 100 pounds of potassium chlorate to 14 
 pounds of the manganese that it does not 
 require so much heat to liberate the oxy- 
 gen only about 200 F., so that in prac- 
 tice this is usually done. If sodium chlor- 
 ate is used, the amount of manganese is 
 increased somewhat. Potassium chlorate 
 will give off about five cubic feet of oxygen 
 per pound and the sodium chlorate will 
 produce about 12% more oxygen per 
 pound. Sodium chlorate is not so stable 
 a compound as potassium chlorate, and 
 the latter chemical was in much greater 
 favor than the former. 
 
 At the prevailing prices of these chemi- 
 cals before the European War, the gas 
 could be made for about 2 cents per cubic 
 foot, and of a purity ranging from 85% to 
 98%, depending entirely upon the method 
 and care exercised in purifying. 
 
 There were two methods of making oxy- 
 gen by this process. One consisted in gen- 
 erating the gas under its own pressure and 
 was designated by the trade as a "Self- 
 Compressing ' ' type. The gas made by this 
 
rfU OXY-ACETYLENE WELDING & CUTTING. 
 
 method was of low purity and was at- 
 tended by hazards of so serious a character 
 that the better class of manufacturers tried 
 to discourage its use. The other method 
 consisted of heating the chemicals in a 
 sealed retort, allowing the gas to pass 
 through several scrubbers and purifiers, 
 collecting in a gas holder and then com- 
 pressing into tanks. The present price of 
 chemicals makes this method impractical. 
 
 ERIN'S PROCESS 
 
 or 
 BARIUM OXIDE PROCESS. 
 
 In this method of making oxygen, barium 
 oxide is used and the gas is produced by 
 the alternate formation of barium dioxide 
 and its decomposition into barium oxide. 
 The installation of a plant requires con- 
 siderable space and special heating require- 
 ments are necessary so as to produce a 
 working temperature of 800 F. The proc- 
 ess consists in heating barium oxide and 
 directing upon it a blast of air, when it 
 takes up oxygen from the air and forms 
 barium dioxide (Ba0 2 ). The tempera- 
 ture is then raised and the barium dioxide 
 decomposes into barium oxide and oxygen. 
 The process is theoretically simple, but in 
 practice presents certain serious difficul- 
 ties. At one time several of these plants 
 were operating in this country, but they 
 
OXYGEN. Ol 
 
 were not a commercial success and were 
 abandoned. 
 
 LAYOISITE PROCESS. 
 
 This is a trade name, lavoisite being a 
 chlorine product. The process consists in 
 bringing together the chemical and water 
 that has been heated to about 180 P., when 
 oxygen is evolved. One pound of lavoisite 
 and one-half pound of water will produce 
 one cubic foot of oxygen of excellent pur- 
 ity. The cost is about the same as the 
 chlorate process. 
 
 ELECTROLYSIS OF WATER PROCESS. 
 
 Oxygen and hydrogen are liberated when 
 a suitable electric current is passed 
 through water whose conductivity has been 
 increased by the addition of either an acid 
 or an alkali. From the positive pole will 
 pass oxygen and from the negative pole 
 will pass hydrogen. There will be generated 
 2 cubic feet of hydrogen for each 1 cubic 
 foot of oxygen. The vessel in which the 
 electrolytic action takes place is called a 
 cell. This cell is divided or separated into 
 two chambers by means of a partition 
 usually of pure asbestos cloth. The object 
 of this partition is to keep the two gases- 
 hydrogen and oxygen from mixing, so 
 that it is of the highest importance that 
 these asbestos diaphragms or partitions 
 be of the very best of material in order that 
 
32 OXY-ACETYLENE WELDING & CUTTING. 
 
 the danger from rupture shall be mini- 
 mized. Should the hydrogen and the oxygen 
 be allowed to mix, it would be attended by 
 very grave danger, as even so low a mix- 
 ture as 5% hydrogen and the remainder 
 of oxygen or vice versa will explode. 
 
 Oxygen made by this process is usually 
 of an excellent quality; gas 98% pure 
 should be obtained direct from the cells 
 and if purified will be in excess of 99% 
 pure. 
 
 Various types of cells are offered the 
 public. The claims of the manufacturers 
 as to the efficiency range anywhere from 3 
 to 3.8 cubic feet of oxygen and twice that 
 amount of hydrogen per kilowatt hour. 
 Probably 3^2 cubic feet of oxygen would be 
 a conservative figure. Assuming that an 
 electric current rate of one cent per K. 
 W. H. was obtained, 100 cubic feet of oxy- 
 gen would cost 28 cents. To this must be 
 added interest on investment, deprecia- 
 tion, labor, overhead and cost of compress- 
 ing into tanks. This is on the assumption 
 that the hydrogen is not marketable. How- 
 ever, in recent years there has been created 
 a quite considerable demand on the part of 
 soap and cottonseed lard manufacturers 
 for hydrogen, for what is known as "oil- 
 hardening." Where the hydrogen can be 
 utilized, this effects a very material saving 
 
OXYGEN. 33 
 
 in the cost of the oxygen and under these 
 conditions the electrolytic process will be 
 a strong competitor with any process. A 
 number of industrial concerns throughout 
 the country have installed small electro- 
 lytic plants, primarily to obtain hydrogen. 
 This gives them as a by-product a very 
 limited amount of oxygen and some are at- 
 tempting to market it. We would strongly 
 advise against the use of this gas and un- 
 hesitatingly recommend that the customer 
 purchase oxygen only from those concerns 
 who are engaged primarily in the oxygen 
 business, for the reason that the concern 
 whose principal business is the manufac- 
 ture and sale of oxygen is not only much 
 more apt to appreciate the necessity for 
 pure gas, but as his reputation is at stake 
 will undoubtedly more frequently test his 
 gas for impurities than the concern who 
 is in the business merely as a side-issue. 
 
 LIQUID AIR PROCESS. 
 
 Obtaining oxygen by the liquid air 
 method is a refrigeration process. By 
 compressing the air and then allowing 
 it to expand through a small opening 
 a temperature sufficiently low to liquefy, 
 the air is obtained. This tempera- 
 ture is 374 below zero F. at atmospheric 
 pressure a temperature so cold that it is 
 almost impossible to realize it. The nitro- 
 
34 OXY-ACETYLENE WELDING & CUTTING. 
 
 gen is allowed to evaporate, leaving liquid 
 oxygen behind. The liquid oxygen is in 
 turn allowed to gasify and is led to suitable 
 gas holders, from which it is compressed 
 into steel drums or tanks. The perfection 
 of this process is due very largely to the 
 efforts of Linde, Claude and Hildebrandt. 
 
 It is possible to obtain oxygen of a high 
 purity by this process. About 20% is added 
 to the manufacturing cost by increasing 
 the purity from 92% to 97%, and further 
 increasing the purity to 99% entails an ad- 
 ditional 10% to the manufacturing cost. 
 From this it will be readily seen that there 
 is always the temptation during exceed- 
 ingly busy times to decrease the purity of 
 the gas. The impurity in liquid air oxygen 
 is nitrogen, an inert gas. The cost of oxy- 
 gen by this process depends upon the size 
 of the installation and whether the plant 
 is operated continuously. Claude, in his 
 work on Liquid Air, Oxygen and Nitrogen, 
 states that oxygen can be made "for 2 
 centimes the cubic meter." A centime is 
 equivalent to one-fifth of a cent and a cubic 
 meter is equal to 35.3 cubic feet, so that 
 this amount of gas would cost two-fifths of 
 a cent, or 100 cubic feet of gas would cost 
 one and one-fifth cents. If these figures 
 are correct, he did not take into consid- 
 eration, depreciation, labor, overhead, etc. 
 
OXYGEN. 35 
 
 What is the present market price of Oxy 
 
 gen? 
 
 From-lVi cents per cubic foot, to very 
 large users, to 2 cents per cubic foot tt) 
 small users. 
 
 In irhdt land of containers is Oxygen fur- 
 nished? 
 
 In steel drums in which the gas is com- 
 pressed to about 1800 pounds. 
 When a gas is compressed to so high a 
 pressure, is there not danger of leak- 
 age at the tank valve? 
 Yes. The purchaser should insist on 
 valves that will open and close easily and 
 which will not leak around or through the 
 packing gland regardless as to the position 
 of the valve stem. 
 
 What is the policy of the various Oxygen 
 Companies with reference to furnish- 
 ing the steel drums? 
 To responsible parties they will furnish 
 the tanks free for a period of 30 days, but 
 they retain the right to make a rental 
 charge of a small amount for the tank if 
 it is not returned within the 30 days. 
 What capacity tanks are usually fur- 
 nished? 
 
 100 cubic feet, 150 cubic feet, 200 cubic 
 feet and 250 cubic feet. 
 Does the temperature of the air affect the 
 pressure in the tank" Yes. 
 
36 OXY-ACETYLENE WELDING & CUTTING. 
 
 Ho iv? 
 
 As the temperature increases the pres- 
 sure of the gas in the tank increases on ac- 
 count of it expanding and as the tempera- 
 ture decreases, the pressure drops. 
 
 Give table showing the different pressures 
 at various temperatures? 
 
 Table of pressures per degree for tanks carrying 
 1800-lbs. at 68 degrees P. Pressure in pounds per 
 degree at any temperature from zero "P." to 100 
 degrees above zero "P." inclusive, with the volume 
 remaining constant at all times. 
 
 Temp. 
 
 T>eg. 
 
 tr 1 
 
 Press. 
 Lb. 
 Per, 
 Des. 
 
 Temp. 
 
 I>eg. 
 F. 
 
 Press. 
 Lb. 
 Per. 
 Deg. 
 
 Temp. 
 
 Degi 
 
 F - 
 
 Press. 
 Lb. 
 Per. 
 Dcg. 
 
 Temp. 
 
 Deg. 
 F. 
 
 Press. 
 Lb. 
 Per. 
 Deg. 
 
 ! 150X 20 
 
 10-57 
 
 51 
 
 1743 76 1828 
 
 i irr,2 27 
 
 1060 
 
 52 
 
 1746 
 
 77 1831 
 
 2 1575 i 28 
 
 1(564 
 
 53 
 
 1749 
 
 78 1835 
 
 3 1 r>79 
 
 - 29 
 
 1667 
 
 54 
 
 1753 
 
 79 
 
 1838 
 
 4 1582 
 
 30 
 
 1071 
 
 55 
 
 1756 
 
 80 
 
 1842 
 
 6 
 
 1585 
 
 31 
 
 1074 
 
 56 
 
 1760 
 
 81 
 
 1845 
 
 6 
 
 1589 
 
 32 
 
 1678 
 
 57 
 
 1763 
 
 82 
 
 1848 
 
 7 
 
 1592 
 
 33 
 
 1681 
 
 58 
 
 1766 
 
 83 
 
 1852 
 
 8 
 
 1590 
 
 34 
 
 1684 
 
 59 
 
 1770 
 
 84 
 
 1855 
 
 9 
 
 1599 
 
 35 
 
 1088 
 
 60 
 
 1773 
 
 85 
 
 1859 
 
 10 
 
 1603 
 
 36 
 
 1691 
 
 61 
 
 1777 
 
 86 
 
 1862 
 
 11 
 
 1006 
 
 37 
 
 1695 
 
 62 
 
 1780 
 
 87 
 
 1865 
 
 12 
 
 1609 
 
 38 
 
 1698 
 
 63 
 
 1784 
 
 88 
 
 1869 
 
 13 
 
 1613 
 
 39 
 
 1701 
 
 64 
 
 1787 
 
 89 
 
 1872 
 
 14 
 
 1610 
 
 40 
 
 1705 
 
 65 
 
 1790 
 
 '90 
 
 1876 
 
 15 
 
 1020 
 
 41 
 
 1708 
 
 60 
 
 1794 
 
 91 
 
 1879 
 
 16 
 
 1623 
 
 42 
 
 1712 
 
 07 
 
 1797 
 
 92 
 
 1883 
 
 17 
 
 1626 
 
 43 
 
 1715 
 
 68 
 
 1800 
 
 93 
 
 1886 
 
 18 
 
 1630 
 
 44 
 
 1719 
 
 69 
 
 1803 94 
 
 1889 
 
 19 
 
 1633 i 45 
 
 1722 
 
 70 
 
 1807 95 
 
 1893 
 
 20 
 
 16-37 46 
 
 1725 
 
 71 
 
 1811 96 1895 
 
 21 
 
 1040 i 47 
 
 1729 
 
 72 
 
 1814 ! 97 1900 
 
 22 i 1043 
 
 48 
 
 1732 
 
 73 
 
 1818 98 1903 
 
 23 i 1647 
 
 49 
 
 1730 
 
 74 
 
 1821 99 1906 
 
 24 1650 
 
 50 
 
 1739 
 
 75 
 
 1824 j 100 1910 
 
 25 
 
 1654 
 
 
 
 
 
 1 
 
 Of what value is this table? 
 
 If the temperature to which the tank has 
 
OXYGEN. 37 
 
 been exposed is known, by referring to the 
 column adjoining, there is shown the pres- 
 sure that the tank should be under if it is 
 what is known as a "full" tank. As an 
 example, suppose the temperature was 32 
 F., and the tank had been exposed to this 
 temperature sufficiently long for the gas 
 to be cooled to the same point, then the 
 pressure on the gauge would indicate 1678 
 pounds. On the other hand, assume that 
 it was summer and the temperature 97 F. 
 Then the pressure should be 1900 pounds. 
 In both cases there was the same amount 
 of gas in each tank, but the pressures dif- 
 fered, due solely to the gas in the latter 
 case expanding and in the former con- 
 tracting as the temperature varied. 
 
 We see from the table above that tempera- 
 ture affects the pressure of gas. Is 
 there any fixed rule for determining 
 this? 
 
 It has been found that for every change 
 in temperature of one degree Fahrenheit 
 there is a corresponding change in volume 
 which amounts to 1/491 of the original vol- 
 ume of the gas. If a gas occupying one 
 cubic foot of space under a temperature of 
 say, 70 F. would be raised to a tempera- 
 ture of 71 F., the volume would be in- 
 
38 OXY-ACETYLENE WELDING & CUTTING. 
 
 creased 1/491 of one cubic foot. For each 
 change in temperature of one degree Fah- 
 renheit there is a corresponding change in 
 pressure of approximately 3.42 pounds. 
 
 What does this suggest? 
 
 That some certain degree of tempera- 
 ture should arbitrarily be chosen as a 
 standard from which to measure oxygen. 
 
 Has this been done? 
 
 Yes. Most oxygen companies have taken 
 70 F., some 68* F. 
 
 How do you determine the contents of a 
 cylinder under pressure? 
 
 It is first necessary to know the contents 
 of the cylinder at atmospheric pressure. 
 This is determined by multiplying the area 
 of the head by the length of the cylinder. 
 The area of the head is obtained by multi- 
 plying the square of the diameter by .7854. 
 Thus a cylinder having a diameter of 2 feet 
 and a length of 3 feet will have a cubical 
 contents of .7854x(2x2)x3 or 9.4248 cubic 
 feet. After the cubic contents have been 
 found it is only necessary to multiply this 
 by the pressure in atmospheres to find the 
 cubic contents under any pressure. 
 
 What is an atmosphere? 
 
 It is the pressure of the air at sea level 
 and has been definitely determined to be 
 
OXYGEN. oKJ 
 
 14.7 pounds, but for rough calculation 15 
 pounds is generally used. 
 
 // a cylinder lias a cubic contents of one 
 cubic foot at atmospheric pressure 
 (zero gauge pressure), what would be 
 the cubic contents at 1800-pound pres- 
 sure? 
 
 The 1800-pound pressure is reduced to 
 atmospheres by dividing by 15 pounds or 
 one atmosphere. The 1800 pounds is 
 found to be equivalent to 120 atmospheres. 
 The cubic contents of the cylinder 1 cubic 
 foot is then multiplied by 120, the number 
 of atmospheres of pressure and a product 
 of 120 cubic feet is obtained. In other 
 words, there is enough gas in this tank 
 which is under 1800 pounds pressure to 
 fill a tank of 120 cubic feet capacity under 
 only ordinary atmospheric pressure. 
 
 In practice liow is the amount of Oxygen 
 
 in a tank determined? 
 
 Most manufacturers of apparatus have a 
 gauge marked on the dial to read both in 
 pounds pressure and in cubic feet. 
 
 It may be of interest to some to know the 
 amount of gas in the different size of oxy- 
 gen cylinders under varying pressures. We 
 accordingly give a table herewith for tanks 
 holding 100, 150 and 200 cubic feet of gas 
 under 1750 pounds pressure. 
 
Press in Lbs 
 
 . 100 cu. ft. 
 
 150 cu. ft. 
 
 200 cu. ft. 
 
 per 
 
 Tank 
 
 Tank 
 
 Tank 
 
 Sq. In. 
 
 Cu. Ft. 
 
 Cu. Ft. 
 
 Cu. Ft. 
 
 15 
 
 .855 
 
 1.282 
 
 1.710 
 
 30 
 
 1.710 
 
 2.565 
 
 3.420 
 
 45 
 
 2.565 
 
 3.84 
 
 5.120 
 
 60 
 
 3.42 
 
 5.13 
 
 6.84 
 
 75 
 
 4.275 
 
 6.4 
 
 8.55 
 
 90 
 
 5.13 
 
 7.69 
 
 10.26 
 
 105 
 
 5.985 
 
 8.97 
 
 11.97 
 
 120 
 
 6.84 
 
 10.26 
 
 13.68 
 
 135 
 
 7.695 
 
 11.53 
 
 15.39 
 
 150 
 
 8.55 
 
 12.82 
 
 17.1 
 
 200 
 
 11.4 
 
 17.1 
 
 22.8 
 
 250 
 
 14.25 
 
 21.37 
 
 28.5 
 
 300 
 
 17.10 
 
 25.65 
 
 34.2 
 
 350 
 
 19.95 
 
 29.92 
 
 39.9 
 
 400 
 
 22.8 
 
 34.2 
 
 45.6 
 
 450 
 
 25.65 
 
 38.47 
 
 51.3 
 
 500 
 
 28.5 
 
 42.7 
 
 57. 
 
 550 
 
 31.65 
 
 47.47 
 
 63.3 
 
 600 
 
 34.50 
 
 51.7 
 
 69. 
 
 650 
 
 37.35 
 
 56. 
 
 74.7 
 
 700 
 
 40.2 
 
 60.3 
 
 80.4 
 
 750 
 
 43.05 
 
 64.57 
 
 86.1 
 
 800 
 
 45.09 
 
 68.8 
 
 91.8 
 
 850 
 
 48.75 
 
 73.12 
 
 97.5 
 
 900 
 
 51.6 
 
 77.4 
 
 103.2 
 
 950 
 
 54.45 
 
 81.67 
 
 108.9 
 
 1000 
 
 57.5 
 
 86.2 
 
 115. 
 
 1050 
 
 60.35 
 
 90.52 
 
 120.7 
 
 1100 
 
 63.2 
 
 94.8 
 
 126.4 
 
 1150 
 
 66.05 
 
 99. 
 
 132.1 
 
 1200 
 
 68.9 
 
 103.3 
 
 137.8 
 
 1250 
 
 71.75 
 
 107.6 
 
 143.5 
 
 1300 
 
 74.60 
 
 111.9 
 
 149.2 
 
 1350 
 
 77.45 
 
 116.17 
 
 154.9 
 
 1400 
 
 80.20 
 
 120.3 
 
 160.4 
 
 1450 
 
 83.05 
 
 124.5 
 
 166.1 
 
 1500 
 
 85.9 
 
 128.8 
 
 171.8 
 
 1550 
 
 88.75 
 
 133.12 
 
 177.5 
 
 1600 
 
 91.5 
 
 137.2 
 
 183. 
 
 * 1650 
 
 94.35 
 
 141.5 
 
 188.7 
 
 1700 
 
 97.2 
 
 145.8 
 
 194.4 
 
 1750 
 
 100.05 
 
 150. 
 
 200.1 
 
OXYGEN. 
 
 41 
 
 Does the purity of Oxygen have any in- 
 fluence on welding or cutting? 
 
 Any impurity in the oxygen will lower 
 its efficiency. This is not so noticeable in 
 welding if the impurity is not in excess of 
 2% or 3%, but in cutting it is claimed that 
 even a \% impurity is apparent not only 
 as to the time and the quantity of oxygen 
 necessary to do the work, but also the ap- 
 pearance of the cut. 
 
 Some years ago, Mr. J. M. Morehead in 
 a paper read before the International 
 Acetylene Association, presented the re- 
 sults of test on the cutting power of oxy- 
 gen of varying purity. His table follows : 
 
 METAL CUT MILD STEEL PLATE %" THICK. 
 
 
 K 
 
 p 
 
 0! 
 
 o 
 a 
 8 
 
 
 o 
 
 W 
 
 1 
 
 K 
 
 0| 
 
 V 
 
 e 
 
 
 e 
 
 2 
 
 
 o 
 
 o 
 
 1 
 
 ft 
 
 S-i Q 
 
 |1 
 
 f-l 
 
 0^ 
 
 Appearance of Cut 
 
 a 
 
 C 
 
 fij 
 
 9) 
 
 s 
 
 11 
 
 jl 
 
 E? - 
 
 a i 
 
 If 
 
 
 H 
 
 
 
 H 
 
 ^ 
 
 H 3 
 
 Ho 
 
 0^ 
 
 ^g 
 
 ^0 
 
 
 1 99.3 
 
 67% 272 
 
 7.5 
 
 48 
 
 1 . 3 Taken asUnit 
 
 Very good 
 
 2 
 
 98. 
 
 67% 285 ! 9.1 i 51 1.6 23% 6% | Good cut 
 
 a 
 
 97.6 
 
 67% i 295 
 
 9.8 
 
 52 1.7 31% 8% 1 Fair cut 
 
 4 
 
 96.8 
 
 68% i 363 
 
 11.8 
 
 64 2. 54% 
 
 33% Fair cut 
 
 5 
 
 96.4 
 
 67% 360 
 
 11.3 
 
 64 2.1 61% 
 
 33% 
 
 Ragged and cindery 
 
 6 
 
 95. 
 
 67 % 377 
 
 11.6 67 
 
 2. 61% 
 
 39% 
 
 Ragged, dirty and cindery 
 
 7 
 
 92. 
 
 67 V 2 551 
 
 16. 
 
 98 
 
 2.7 108% ; 104% 
 
 Very dirty and rough 
 
 8 
 
 87.3 67% 
 
 660 
 
 16.2 
 
 117 
 
 2.9 123% 114% i Blew back badly, very rough 
 
 9 
 
 83.3 
 
 67% 855 
 
 18.9 
 
 153 3.4 154% ! 214% i Very rough and ragged, not 
 
 
 
 
 properly cut 
 
 Subsequent to the publication of this 
 table, the writer experimented along the 
 
42 OXY-ACETYLENE WELDING & CUTTING. 
 
 same lines. While we were never able to 
 show so marked a difference in the cutting 
 power between pure oxygen and that of 
 lesser purity as indicated by Mr. Morehead, 
 still the difference was such as to justify 
 us in recommending that users of oxygen 
 insist upon being furnished oxygen of a 
 high degree of purity. 
 
CHAPTER III. 
 
 WELDING AND CUTTING TORCH. 
 
 THE OXY-ACETYLENE WELDING TORCH. 
 What are the requisites for a good welding 
 torch? 
 
 The oxy-acetylene welding torch should 
 be simple of design, light, yet sufficiently 
 strong in its construction and provide for 
 the bringing together of oxygen and acety- 
 lene and mixing these gases in the correct 
 proportions. 
 
 Fig. 2. 
 An Oxy- Acetylene AY elding Torch. 
 
 Of u'hat does a welding torch consist? 
 
 It consists of a handle through which 
 pass two conduits or tubes, one of which is 
 for the acetylene and the other for the 
 oxygen. These tubes are each provided 
 with cocks or valves and they in turn are 
 connected to the hose which carry the gases 
 from their source of supply. The other 
 
 43 
 
44 OXY-ACETYLENE WELDING & CUTTING. 
 
 ends of the two tubes are firmly connected 
 with what is known as the- torch head. It 
 is either here or in the tip itself that the 
 mixture is accomplished. Tips of various 
 sizes are usually furnished. 
 
 In the manufacture of a torch what have 
 been the chief difficulties to over- 
 come? 
 First, the tendency to " flash-back," and 
 
 second, a waste of oxygen. 
 
 What produces a "flash-back"? 
 
 Primarily it is produced by allowing the 
 velocity or speed of the mixed gases (acety- 
 lene and oxygen) to drop below the speed 
 of propagation of the flame. This occurs 
 when the pressure in the acetylene gener- 
 ator or tank becomes low. This may oc- 
 cur by reason of the partial obstruction of 
 pipes or openings in the torch or tips. 
 
 What is meant by "the velocity of propa- 
 gation of the flame"? 
 
 The speed with which a mixture of acety- 
 lene and oxygen will travel when ignited. 
 Row fast does a mixture of Acetylene and 
 Oxygen travel when lighted? 
 
 About 330 feet per second. 
 What do we learn from this? 
 
 That the two gases when mixed should 
 be under a pressure sufficient to insure a 
 speed of over 330 feet per second when 
 
FLASH-BACKS. 45 
 
 the mixture escapes from the nozzle of 
 
 the tip. 
 
 How does tills prevent a "flash-back"? 
 
 If the gases passing out of the tip are 
 traveling at a speed of, say, 350 feet per 
 second, then if the flame can only travel 
 330 feet per second, it follows that the 
 flame cannot pass into the torch. The un- 
 ignited gases traveling faster will always 
 push the flame away from the tip. 
 
 What is meant l>y a "waste of Oxygen" in 
 
 a torch? 
 
 Two and one-half volumes of oxygen 
 are required to completely consume one 
 volume of acetylene. Theoretically one 
 and one-half volumes of oxygen can be 
 taken from the air and one volume from 
 the tanked gas. So much for theory. It 
 is almost an axiom that one never obtains 
 in practice what they should in theory. The 
 oxy-acetylene torch is no exception. In- 
 stead of one cubic foot of tanked oxygen 
 being consumed for each one cubic foot 
 of acetylene, in practice the best torches 
 use from 10 to 15% more oxygen than 
 acetylene and any increase in this amount 
 means among other things a waste of oxy- 
 gen. 
 
 Hotv are welding torches classified? 
 
 According to the pressure of the acety- 
 lene. 
 
4() OXY-ACETYLtENE WELDING & CUTTING. 
 
 Row many and what are tltese classes in 
 
 this country? 
 There are two: 
 
 1st Those using low pressure 
 
 acetylene and 
 
 2nd Those using what is called 
 high pressure acetylene. 
 
 What is meant by Loiv and High Pressure 
 Acetylene 
 
 The terms are simply comparative. 
 "Low pressure'' torches are those de- 
 signed primarily to use acetylene from a 
 generator or gas-holder in which the pres- 
 sure is about three inches of water column 
 or practically two ounces. 
 
 "High pressure" torches are those de- 
 signed to use acetylene at a pressure of 
 from one pound in the smallest tips to 
 as high as ten pounds in the largest tips. 
 The acetylene is taken either from a tank 
 in which the gas is compressed or from a 
 special pressure acetylene generator. It 
 will be seen that the highest pressure used 
 ten pounds is really not a high pres- 
 sure except as compared with the "low 
 pressure " torch using about two ounces. 
 There has been some objection to the use 
 of the term "high pressure" for fear that 
 the public might construe "high" pres- 
 sure to possibly mean a dangerous pres- 
 sure, and some have preferred to use the 
 
LOW PRESSURE TORCH. 47 
 
 term ' ' medium ' ' pressure. The terms high 
 pressure and medium pressure as used in 
 this country are synonymous. There is no 
 more danger working under ten pounds 
 pressure than there is under two ounces. 
 
 How is a loiv pressure torch constructed? 
 The acetylene under a few ounces of 
 pressure flows into a compartment 
 through which the oxygen is passing at a 
 high velocity. The high speed of the oxy- 
 gen draws or sucks in the acetylene. This 
 is what is known as the injector principle. 
 
 How is the high pressure torch con- 
 structed? 
 
 Both the acetylene and oxygen are un- 
 der a few pounds pressure. These gases 
 flow through openings accurately de- 
 termined into a mixing chamber from 
 which they are conveyed to the nozzle. 
 
 Which type of torch is considered the best? 
 The high pressure. 
 
 Why? 
 
 Because numerous tests have proven 
 that in practice, the high pressure torch 
 of good design using the acetylene under 
 a few pounds pressure consumes practical- 
 ly equal quantities of acetylene and oxy- 
 gen, whereas the low pressure torch re- 
 quires an excess of oxygen ranging from 
 10% to 30% more than high pressure 
 
48 OXY-ACETYLENE WELDING & CUTTING. 
 
 torches, depending upon the size of the 
 tip. In a series of experiments conducted 
 by the Engineering Experiment Station 
 of the University of Illinois the propor- 
 tion of acetylene at normal regulation aver- 
 aged 42% in the low pressure torch. This 
 is a ratio of 1.38 volumes of oxygen to one 
 of acetylene. A good high pressure torch 
 will not use nearly so much oxygen. 
 
 Are there any authorities whose tests prove 
 
 the above assertion? 
 Yes. 
 
 Name a few of them and state briefly what 
 they have to say? 
 
 ' ' For blow pipes of high pressure all the 
 experiments agree in showing that the re- 
 spective volumes of gas used are prac- 
 tically equal, and this is obtained in prac- 
 tice if the operators are competent." 
 
 "The blow pipes for low pressure acety- 
 lene are those with which the most difficulty 
 has been obtained even in approaching the 
 theoretical equal volumes." 
 
 GBANJON & ROSEMBERG. 
 
 "In the high pressure type the adjust- 
 ment of the flame is far easier with both 
 gases under pressure ; once the adjustment 
 is made right it remains so ; a more inti- 
 mate mixing of the gases is obtained than 
 in the low pressure type, and this secures 
 
AUTHORITIES. 49 
 
 higher efficiency. This is of considerable 
 importance, as it is found that with high 
 pressure blow pipes considerably less 
 acetylene and oxygen is required to do a 
 fixed quantity of work than is necessary 
 with the low pressure blow pipe." 
 
 L. A. (TROTH. 
 
 "In the high pressure type torch, both 
 gases being under pressure maintain quite 
 accurately their relative proportions when 
 once properly adjusted. In the injector or 
 low pressure torch, each change of tem- 
 perature of the blow pipe or of the tip 
 forming the outlet causes some variation 
 in the size of the opening and consequently 
 variations in the relative proportions of 
 the issuing gases." 
 
 WHITTEMORE. 
 
 "The low pressure torch is defective in 
 that it very often does not carry enough 
 acetylene through it to neutralize the ef- 
 fect of the oxygen, consequently the weld 
 is oxidized." 
 
 RICHARD HART. 
 
 "All burners or torches with oxygen 
 under pressure and acetylene without pres- 
 sure, i. e., injector type, become after a 
 short time of working practically useless." 
 
 "The radiating heat affects the oxygen 
 which is- under pressure, with great veloc- 
 
DU OXY-ACETYLENE WELDING & CUTTING. 
 
 ity in a narrow space in a different way 
 than its action upon the acetylene con- 
 tained in a larger space and without pres- 
 sure. ? ? 
 
 "The result is a decomposition of the 
 flame and a burning of the metal. ' ' 
 
 "This can only be prevented by a skillful 
 welder. ' ' 
 
 DR. A. HILPERT, Berlin. 
 
 In the low pressure torch, the acety- 
 lene is drawn into the tip by the suction 
 of the oxygen operating by a device known 
 as the Giffard Injector. In the injector 
 type of torch the amount of acetylene 
 dratvn in, varies as the square of the oxy- 
 
 What chemical changes take place when 
 
 Oxygen and Acetylene are Imrned? 
 It may be well to state that all combus- 
 tion, with the exception of some unimpor- 
 tant laboratory experiments, is the result 
 of combining carbon with oxygen, hydro- 
 gen with oxygen, or combinations of hydro- 
 gen and carbon, called hydro-carbons, with 
 oxygen. As stated before, acetylene is a 
 hydro-carbon. That is, it contains both 
 hydrogen and carbon. The layman when 
 watching the phenomenon of combustion 
 is apt to consider its action as destroying 
 something. Such is not the case. It is 
 
CHEMICAL CHANGE. 51 
 
 simply a chemical change and invariably 
 combustion finally produces carbonic acid 
 gas or carbon dioxide (C(X) and water or 
 water vapor (H 2 0). In order to properly 
 explain the change or reaction that takes 
 place it becomes necessary to use symbols, 
 but in this case they are simple and Ave 
 feel sure they will be easily understood. 
 
 It may be advisable to state here some 
 of the symbols which we will use, together 
 with what they stand for. 
 
 H is the symbol for hydrogen. 
 
 C is the symbol for carbon. 
 
 is the symbol for oxygen. 
 CO is the symbol for carbon monoxide. 
 COo is the symbol for carbon dioxide or 
 carbonic acid gas. 
 
 H.,0 is the symbol for water or water va- 
 por. 
 
 C,H 2 is the symbol for acetylene. 
 
 Acetylene (C 2 H 2 ), as previously stated, 
 is composed of equal parts of hydrogen and 
 carbon and it unites with an equal volume 
 of oxygen (0 2 ) to form the first reaction. 
 This reaction is indicated by the following 
 equation : 
 
 (a) a,H,+(X=2 CO+H, 
 In other words, 1 molecule, which is the 
 
5Z OXY-ACETYLENE WELDING & CUTTING. 
 
 technical expression for a unit volume of 
 acetylene, unites with 1 molecule of oxygen. 
 A unit volume of oxygen is expressed as 
 2 and is made up of two parts or atoms 
 of oxygen. 
 
 The primary stages of combustion as in- 
 dicated in equation (a) result as indicated 
 in production of 2 unit volumes of carbon 
 monoxide (2 CO) and 1 unit volume of 
 hydrogen (H 2 ) which, like oxygen, is made 
 up of two parts or atoms. Now these prod- 
 ucts of the primary stage of combustion 
 are formed in the small, bluish-white cone 
 of the flame. This is shown in Fig. 3. 
 
 This cone is the zone of greatest heat in 
 the flame. The secondary or final stage of 
 combustion takes place in the outer flame 
 which not only surrounds the small white 
 cone, but extends for quite a considerable 
 distance beyond it. In this outer flame, 
 the carbon monoxide (2 CO) and the hydro- 
 gen (H 2 ) which were shown to have been 
 produced in the small white cone are trans- 
 formed by the addition of more oxygen 
 
WASTE OF OXYGEN. 53 
 
 to carbon dioxide or carbonic acid gas 
 (C0 2 ) and water vapor (H 2 0). This 
 change would appear to be two-phase and 
 may be better understood by the following 
 equations : 
 
 (b) H 2 +0=HoO 
 
 (c) CO+0=C0 2 
 
 The changes that take place as shown 
 by equations (b) and (c) do not and can- 
 not occur in the small white cone of the 
 flame, for the reason that a temperature 
 of 6300 F. is produced at this point, and 
 hydrogen and oxygen will not unite to form 
 water vapor above 3600 F. ? and carbon 
 monoxide and oxygen will not unite to 
 form carbon dioxide at a temperature 
 higher than 2272 F. In other words, the 
 hydrogen and the carbon monoxide must 
 get outside and away from the small white 
 cone where it is cooler before combustion 
 can take place. 
 
 Does the small ivhite cone or the outer 
 flame or both take oxygen from the 
 tank or the air? 
 
 This is a very important point and one 
 which the conscientious manufacturer of 
 welding apparatus has seriously studied. 
 Upon its solution depends whether the 
 torch will be economical or expensive in 
 the consumption of oxygen. Enough oxy- 
 
54 OXY-ACETYLENE WELDING & CUTTING. 
 
 gen should be supplied from the tank for 
 the combustion that takes place in the 
 small white cone and it should stop there. 
 The outer flame will take its oxygen from 
 the air if it is permitted to do so. As the 
 tanked gas cost money and the air is free 
 and as the outer flame is not for welding, 
 economy would dictate that as much air as 
 possible be used. It is a notable fact that 
 in the low pressure torch, the tendency is 
 for the oxygen, by reason of its high pres- 
 sure, to pass through the small white cone 
 and supply the outer flame with a part 
 of this element. This will always be an 
 objection to the low pressure type of torch. 
 
 What other objections does the low pres- 
 sure torch possess? 
 
 In a series of experiments carried out 
 in France by the Union of Autogenous 
 Soldering some six different torches using 
 low pressure acetylene were tested to de- 
 termine, first, just what the ratio of oxygen 
 to acetylene was shortly after ignition, and 
 second, whether the ratio was constant 
 after the torch had been in operation for 
 some time and had become thoroughly 
 heated. The results of these tests are as 
 follows : 
 
COMPARISON' OF TORCHES. 
 
 Torch 
 A 
 B 
 C 
 D 
 E 
 P 
 
 Consumption 
 of acetylene 
 per hr. 
 20 Cu. Ft. 
 6 Cu. Ft. 
 12 Cu. Ft. 
 16 Cu. Ft. 
 20 Cu. Ft. 
 26 Cu. Ft. 
 
 Consumption 
 of oxygen 
 per hr. shortly 
 after ignition 
 28. Cu. Ft. 
 8.1 Cu. Ft. 
 19.2 Cu. Ft. 
 26.4 Cu. Ft. 
 29. Cu. Ft. 
 40.3 Cu. Ft. 
 
 Consumption 
 of oxygen 
 per hour after 
 torch became 
 hot 
 36. Cu. Ft. 
 10. Cu. Ft. 
 22.8 Cu. Ft. 
 30.4 Cu. Ft. 
 31. Cu. Ft. 
 45.5 Cu. Ft. 
 
 It will be seen from this table that there 
 was a considerable increase in the consump- 
 tion of oxygen upon the torches becoming 
 heated. This was found to occur only in 
 torches using low pressure acetylene. The 
 effect of expansion on the two gases op- 
 erating at such a marked difference in 
 pressures is not the same. 
 
 The clfii-itt ltd* been made here tlt<ik the high 
 pressure torch is more efficient than 
 the Ion: pressure torch. Will all high 
 pressure torches uphold this conten- 
 tion? 
 
 Not at all. There are inefficient high 
 pressure torches due to poor design, or 
 poor workmanship or both. In a series 
 of tests with a number of torches in which 
 the acetylene consumption was fixed at 10 
 cubic feet per hour it was found that the 
 best result showed 12% more oxygen con- 
 sumed than acetylene; the worst 90% more 
 
5() OXY-ACETYLENE WELDING & CUTTING. 
 
 oxygen than acetylene, while the average 
 was 33%%. 
 
 The result of these tests should convince 
 those who are using autogenous welding, 
 or who are contemplating using it, that 
 a few pieces of brass do not constitute an 
 efficient welding torch. 
 
 One would gather from the above that 
 ivhile the gas pressures used in the 
 various high pressure torches ivere 
 practically the same, the manner in 
 which the gases mix must be different. 
 That is correct. Some high pressure 
 
 torches mix in the tip, some in the head 
 
 and others in or near the handle of the 
 
 torch. 
 
 Which is the best type of high pressure 
 
 torcM 
 
 In the first place, practically all torches 
 now have interchangeable tips. These tips 
 vary in size, producing a small, medium 
 or large flame, as may be desired. Inas- 
 much as metal varies in thickness, this per- 
 mits of producing a welding flame of suit- 
 able size for the work at hand. The writer 
 is strong in the belief that the torch which 
 provides a separate and distinct mixture 
 for each individual tip, will come the near- 
 est to theoretical perfection. To illustrate, 
 Fig. 4 shows a cut of such a tip. 
 
GAS MIXTURE IN TIP. 
 
 57 
 
 "0" is the oxygen 
 inlet. "A" "A" is an 
 annular chamber in- 
 which there are a num- 
 ber of holes drilled to 
 meet the oxygen inlet. 
 These openings form 
 the acetylene inlets to 
 a mixing chamber and 
 nozzle "M. " Between 
 inlet "0" and inlets 
 "A" "A" there is a 
 flat seat or seal which 
 prevents the gases 
 from mixing until they 
 reach their proper 
 destination. As the 
 mixing chamber and 
 nozzle "M" varies for 
 each tip, so the oxygen inlet "0" and the 
 acetylene inlets "A" "A" vary accord- 
 ingly, being proportioned to supply the 
 correct amount of acetylene and oxygen 
 under the proper pressures. 
 
 It must be clear that the amount or 
 volume of gas passing through an opening 
 depends, upon the pressure and the size 
 of the opening. Now the pressure is con- 
 trolled by the regulators, and with a tip 
 of this design it is a simple matter to drill 
 
OS OXY-ACETYLENE WELDING & CUTTING. 
 
 the proper openings, once they have been 
 correctly determined. 
 
 Those torches which mix in the head or 
 near the handle provide no means of ac- 
 curately changing the volumes. They 
 simply provide for one mixture and of 
 course this must be for their latest tip. 
 When lighter work is desired a smaller 
 tip which chokes down the flow of the gas 
 is used. There can be no real accuracy 
 of mixture with such a design. 
 
 THE CUTTING TORCH. 
 
 What metals can be cut with the torch? 
 
 Wrought iron and steel are the only 
 metals, which can be cut with oxygen. 
 Why? 
 
 Cutting with oxygen is simply a burning 
 of the metal a rapid oxidation. The slag 
 formed is called oxide or iron oxide. This 
 oxide has a much lower melting point than 
 that of the metal and as the burning or 
 cutting progresses the oxide is detached, 
 leaving clean iron for the oxygen to at- 
 tack. 
 
 Copper, brass, aluminum and cast-iron 
 cannot be cut. These metals not only do 
 not oxidize in the same degree as wrought 
 iron or steel, but in addition the oxide 
 which does form has a melting point equal 
 or higher than that of the metal and this 
 prevents it from being detached. 
 
CUTTING STEEL. 59 
 
 Of what does the operation of cutting con- 
 sist? 
 
 It consists first in -heating the wrought 
 iron or steel to redness and then directing 
 upon the heated section a jet of oxygen 
 escaping under a pressure which varies ac- 
 
 An Oxy- Acetylene Cutting Torch. 
 
 cording to the thickness of the metal to be 
 cut. 
 
 In order to cut economically and to secure 
 a clean, smooth cut, what is necessary? 
 That the torch be moved at a regular, 
 even speed and that the speed shall ap- 
 proach as near as possible the maximum 
 rate at which the steel is attacked by the 
 oxygen; that pure oxygen shall be used 
 and that the oxygen jet shall be held as 
 close to the steel as possible. This last 
 is very important. As a matter of fact, 
 the author, after considerable experiment- 
 ing, perfected a cutting torch in which the 
 oxygen jet rests directly on the metal that 
 is being cut. That this is correct in prac- 
 tice is shown by the cut, which in the ma- 
 
60 OXY-ACETYLENE WELDING & CUTTING, 
 
 jority of cases is as smooth as a shear cut. 
 We believe that an explanation as to 
 the theory is convincing in that respect. 
 Any gas when escaping from an orifice does 
 not continue in a straight line, but com- 
 mences to diverge almost at the instant it 
 passes out of the opening. This is illus- 
 trated by Fig. 6. 
 
 Now it must be apparent that if the oxy- 
 gen opening is say % of an inch in diameter 
 that the diameter of the oxygen jet must 
 be about y 2 inch more or less when meas- 
 ured a distance of one inch from the noz- 
 zle, and this diame.ter decreases as we ap- 
 proach nearer the nozzle. The center or 
 core of this oxygen jet is probably pure 
 oxygen, but undoubtedly the outer fringe 
 is contaminated with air which contains 
 80% nitrogen and it is this outer fringe 
 that is responsible for the appearance of 
 the edge of the cut whether clean and 
 sharp or rough and cindery. Elsewhere 
 we have shown the effect of impure oxygen 
 in cutting and if the results of these tests 
 
COST OF CUTTING. 61 
 
 can be relied upon it bears out the above 
 claims. 
 
 Another advantage in resting the oxy- 
 gen jet directly on the metal is that the 
 cut is narrower, therefore less metal has 
 been burned and the operation is more 
 economical. 
 
 Who tvere probably the first to use oxygen 
 for cutting? 
 
 Dr. Menne, a German, and Jbttrand, a 
 Belgian. 
 
 Theoretically, hoiv much oxygen is required 
 to cut a given amount of steel? 
 
 As previously stated, the steel when cut 
 is transformed into iron oxide or more 
 properly magnetic oxide of iron, the chem- 
 ical symbol of which is Fe : , 4 . The atomic 
 weight of iron is 55.9 and that of oxygen 
 16, so that the weights of the iron (Fe) 
 and the oxygen (0) in the iron oxide are 
 in the proportion of 168 to 64 or 21 to 8. 
 The oxygen needed will then be 8/21 times 
 the weight of the steel involved, or 38% 
 of the weight of the steel removed. As- 
 suming that the kerf or cut has a thickness 
 or width of Vs-inch, the weight of steel 
 corresponding to each square inch of the 
 face of the cut is .0352 pound, and 38% 
 of this is .01338 pound, the weight of oxy- 
 gen necessary to make the cut. A pound 
 of oxygen at 32 F. occupies 11.2 cubic feet 
 
62 OXY-ACETYLENE WELDING & CUTTING. 
 
 of space, and .01338 pound is found to be 
 .15 cubic foot. Therefore, theoretically it 
 requires .15 cubic foot of oxygen to cut a 
 square inch of steel if the kerf is Vs-inch 
 wide. 
 
 In practice wliat amount of oxygen lias 
 
 been found necessary? 
 Just about double the theoretical amount. 
 It must b6 remembered that the above has 
 considered only the amount of oxygen re- 
 quired in the oxygen jet. To this must be 
 added the oxygen and the acetylene con- 
 sumed in the heating jets. 
 
 L^ the rt^ajiy detrimental cltanye in material 
 
 *wrien cut with oxugenf^ 
 
 Xo. On high carbon steels there is a 
 slight softening of the metal for a distance 
 of about %-inch from the cut, due to the 
 annealing effect of the heat. Numerous 
 tests have been made and all bear out the 
 above assertion. The results of one such 
 test may prove interesting. A steel plate 
 %-inch thick and 14%-inch long was used. 
 
 TEST NO. 1. TEST NO. 2. 
 
 ORIGINAL STOCK BEFORE 
 
 CUT. 
 
 Tensile 47,620 Ibs. 
 
 Elastic Limit. .31,640 Ibs. 
 
 Elongation 33% 
 
 Reduction of area. . .35% 
 
 AFTEK CUT. 
 
 50,110 Ibs. 
 
 29,930 Ibs. 
 
 33% 
 
 42% 
 
OTHER HEATING AGENCIES. DO 
 
 Can a fuel gas other than acetylene be used 
 in the pre-heating jet? 
 
 Yes. Ordinary coal gas, Pintsch gas, 
 hydrogen or any good hydro-carbon gas 
 can be used. 
 
 Hydrogen has been used quite extensive- 
 ly for cutting, and for extremely heavy 
 work would seem to be better adapted than 
 acetylene. The hydrogen flame is a long 
 one, whereas the acetylene flame is short, 
 and this is probably the reason why on 
 very thick metal hydrogen would seem to 
 be better adapted. 
 
 The cost depends largely upon the price 
 at which the two gases can be purchased, 
 and when any comparison is made the % 
 market price of each, together with the con- 
 sumption, should be stated. 
 
CHAPTER IV. 
 
 APPARATUS AND INSTALLATION. 
 REGULATORS AND REDUCERS. 
 
 The above names used to designate a 
 part of the welding and cutting apparatus 
 would appear to be used synonymously in 
 this country. However, the function of a 
 regulator would seem to be wider in its 
 scope than that of a reducer. A good regu- 
 lator is a very essential part of any welding 
 or cutting equipment. 
 What is the duty or function of a regulator? 
 
 Primarily to reduce the pressure of the 
 oxygen as it flows from the cylinder, and 
 the pressure of the acetylene from its tank, 
 or the generator as the case may be. Its 
 secondary duty is to maintain the desired 
 reduced pressure without fluctuating. Al- 
 most any type of regulator will fulfill the 
 first requirement, but only a high grade 
 one combines both features. 
 How are regulators constructed 
 
 They all utilize the diaphragm principle. 
 The diaphragm is either of metal or rub- 
 ber composition and attached to one side 
 of the diaphragm is a seat which covers 
 and closes the opening in a nipple com- 
 municating with the gas cylinder. There 
 is a spring which rests against the other 
 
 64 
 
CONSTRUCTION OF REGULATOR. 
 
 65 
 
 G/7S OVTl-ET 
 
 Fig:. 7. 
 An Oxygen Regulator. 
 
 side of the diaphragm. When there is no 
 tension on this spring, the parts are so 
 
66 OXY-ACETYLENE WELDING & CUTTING. 
 
 adjusted that the diaphragm holds the seat 
 over the nipple, closing the gas inlet tight, 
 so that no gas can escape from the con- 
 tainer. When some tension is put on the 
 spring, the diaphragm is pushed inward, 
 releasing the pressure of the seat on the 
 nipple and allowing the gas to flow into 
 the body of the regulator. The pressure 
 of the gas climbs until it exceeds the ten- 
 sion of the spring when the diaphragm is 
 pushed outward, again closing the gas in- 
 let. The gas that is in the body of the 
 regulator is used up by the torch until the 
 pressure drops to a point where the spring- 
 tension is the stronger, and the seat opens, 
 allowing gas to again enter the regulator. 
 This continues regularly and might very 
 aptly be compared to breathing. If the 
 seat is perfect, and the flexibility of the 
 diaphragm correctly proportioned to the 
 stiffness of the spring, a very sensitive reg- 
 ulation can be obtained. 
 
 Should an oxygen regulator be provided 
 
 with a cock or valve at its outlet? 
 No, for the reason that if a cock is 
 furnished at the outlet, there is always the 
 temptation for the operator, when the torch 
 is not in use, to shut off the gas at this 
 point rather than at the tank valve. If the 
 regulator seat should leak, trouble might 
 result, whereas if there was no cock a 
 
CARE OF REGULATOR. 67 
 
 burst hose would be the only bad result. 
 
 What are some of the points to be observed 
 in order to keep a regulator in good 
 condition? 
 
 As stated above, the diaphragm is con- 
 tinually breathing or moving and of course 
 the seat is subjected to considerable wear 
 by the reason of its frequent closing and 
 opening of the inlet nipple. If the seat 
 is not perfect, it is of no value and so care 
 must be taken that the movement of the 
 diaphragm closing the seat is not sudden, 
 as the seat will pound on the nipple and 
 quite likely be destroyed. This is caused 
 by the operator opening the tank valve 
 while there is tension on the regulator 
 spring, so if you expect your regulator to 
 give good service, see that the spring ten- 
 sion is released before turning on the gas. 
 
 We have just seen how the regulator seatf 
 could be injured by the diaphragm being 
 suddenly forced outward by the incoming 
 gas. The diaphragm itself may be put 
 out of commission and possibly injury done 
 the seat by reducing from a higher to a 
 lower pressure with the outlet closed. 
 
 To illustrate, suppose that the torch is 
 welding on heavy work which requires an 
 oxygen pressure of 18 or 20 pounds and 
 it is necessary to do some light welding. 
 This requires a small tip with an oxygen 
 
68 OXY-ACETYLENE WELDING & CUTTING. 
 
 pressure of 2 or 3 pounds. If the thumb 
 screw is backed out, releasing the tension 
 on the spring there will be little or no ten- 
 sion against the diaphragm on the spring 
 side and it will be forced outward, and in 
 time so buckle the diaphragm that it will 
 be useless. Th^refore 
 the higher to a ^ 
 
 regulator? 
 A regulator leaks when the seat does not 
 completely seal the opening in the inlet 
 nipple and allows the gas from the tank 
 to enter the body of the regulator. A leak- 
 ing regulator is detected by the hand on 
 the low pressure gauge, which is usually 
 the small gauge, creeping up. When the 
 hand indicator on this gauge shows the 
 pressure creeping 15 or 20 pounds more 
 than the pressure shown when the torch 
 is operating, then there is a serious leak 
 and it is dangerous to continue using a 
 regulator under this condition. When this 
 occurs the regulator should be returned to 
 the manufacturer for repairs. While some 
 undoubtedly w r ould be able to repair their 
 own regulators, in. the vast majority of 
 cases it would be much more satisfactory 
 to return them to the manufacturer who 
 would be in a position to put them in first- 
 class shape. 
 
GAUGES. 69 
 
 It is important that no grease or oil 
 be allowed in the interior of the regulator. 
 If this should be done it might cause an 
 explosion. 
 
 GAUGES. 
 
 The better class of apparatus manufac- 
 turers equip oxygen regulators with two 
 gauges, one of which is a 3000-lb. gauge 
 and the other ranging from 50 pounds to 
 150 pounds. The 3000-lb. gauge usually 
 reads not only in pounds pressure, but also 
 in cubic feet, so that by glancing at this 
 gauge the operator can instantly note both 
 the pressure in the tank and the cubic con- 
 tents. The other gauge, which is usually 
 of smaller diameter, indicates the pressure 
 under which the torch 'is operating. The 
 3000-lb. gauge *should be provided with 
 what is known as a safety back so that in 
 the event that the spring should prove de- 
 fective and burst, injury to the operator 
 will be avoided. 
 
 GOGGLES. 
 
 Tinted or smoked goggles should always 
 be worn by those welding. The tint or de- 
 gree of color depends entirely upon in- 
 dividual taste. For welders doing general 
 repair work a light-smoked and also a dark- 
 smoked goggle should be provided, the 
 lighter colored goggle being used on alum- 
 
70 OXY-ACETYLENE WELDING & CUTTING. 
 
 inum, brass or small castings, while the 
 darker goggles should be worn on heavy 
 cast-iron and steel work. 
 
 Some welders unquestionably wear 
 glasses of too dark a color, the strain on 
 the eye trying to see the work being as 
 injurious as if they wore none at all. The 
 best color is the one which does not tire 
 or strain the eye. 
 
 ACETYLENE GENERATOR. 
 
 One of the most important units that 
 comprise an oxy-acetylene welding plant is 
 the acetylene generator. As previously 
 stated, these are of two types, namely low 
 pressure and high pressure. Nearly every- 
 one is familiar with the low pressure gen- 
 erator by reason of the fact that it is simply 
 a lighting generator. The high pressure 
 generator produces the acetylene under a 
 few pounds pressure. 
 What are the important considerations in 
 
 an acetylene generator? 
 They are: 
 
 1st Safety. 
 
 2nd Cool generation. 
 
 3rd Automatic feed. 
 
 4th Minimum variance in pressure. 
 
 5th Good mechanical construction. 
 What devices should be placed on a gen- 
 erator to insure safety? 
 The most important consideration from 
 
ACETYLENE GENERATOR. 71 
 
 a standpoint of safety is that the feeding 
 mechanism on the generator should be ar- 
 ranged so that it will lock when a given 
 amount of gas has been generated and this 
 means when a given amount of carbide has 
 been fed into the water. If the locking de- 
 vice did not operate, it must be apparent 
 that an excess amount of gas would be 
 generated. 
 
 In the low pressure generator the gas 
 might break the water seal and so escape 
 into the room. 
 
 In the high pressure generator an ex- 
 cessive pressure might occur. 
 
 Safety blow-offs are provided on all first- 
 class generators and these, if operating, 
 would prevent the gas from escaping into 
 the room, but in any event there would be 
 a loss of gas which would be pure waste. 
 
 A flash-back cylinder is necessary on 
 either type of machine. While the chance 
 of the flame flashing back in the generator 
 is rather remote, yet there is the possibility 
 of such a thing happening and safety de- 
 vices of this kind should be attached to all 
 generators. 
 
 COOL-GENERATION. 
 
 Under the head of Acetylene cool-gen- 
 eration was briefly described. By this is 
 
72 OXY-ACETYLENE WELDING & CUTTING. 
 
 meant : supplying a sufficient amount of 
 water to dissipate or keep down the heat 
 of generation. It is imperative that one 
 gallon of water should be supplied for each 
 one pound of carbide in the generator. 
 
 AUTOMATIC FEED. 
 
 What is meant by Automatic Feed? 
 
 By this is meant that the generator will 
 automatically without attention feed car- 
 bide and thereby generate gas for the torch 
 as it is being used, and will cease generat- 
 ing when the torch is not in use. Some 
 machines do not do this and it seriously in- 
 terferes with the welder, as it is necessary 
 for him every few minutes to leave his 
 work and feed by hand some carbide. 
 
 MINIMUM VARIANCE IN PRESSURE. 
 
 In the low pressure generator there is 
 practically no yariance in pressure. With 
 the high pressure generator there is and 
 must be a slight variance in pressure. It 
 is this slight difference in pressure which 
 is taken advantage of to start and stop 
 the "feeding mechanism. This variance in 
 pressure should not exceed a pound or 
 two and this is taken care of by means 
 of a special regulator for high pressure 
 generators. 
 
CONSTRUCTION. 73 
 
 GOOD MECHANICAL CONSTRUCTION. 
 
 It is admitted by all that any machine 
 should have good mechanical construction 
 and the only difference arising is as to 
 what constitutes good mechanical construc- 
 tion. It is the opinion of the writer that 
 welding generators should be built very 
 much more substantial than the ordinary 
 acetylene lighting generator, for the rea- 
 son that very much more work is demanded 
 of the welding generator than is of the 
 lighting machine. 
 
 Some machines have the body of gen- 
 erator riveted and soldered. We are 
 strongly of the belief that this is a mistake. 
 The generator, of course, must be gas-tight 
 and as the rivets do not produce a gas- 
 tight joint, soldering is resorted to. The 
 sheets are usually galvanized iron. Sheet 
 metal workers have long since learned that 
 where solder is applied to galvanized stock 
 if the parts are subject to any movement 
 or strain the galvanizing will peel and, of 
 course, as the solder is attached to the gal- 
 vanizing it means a loose and leaky joint. 
 The pressure in the acetylene generator 
 varies and this causes a breathing of the 
 body or tank portion and in time the solder 
 breaks loose and the gas leaks into the 
 room. Too often in attempting to solder 
 up these loose joints an open light has 
 
74 OXY-ACETYLENE WELDING & CUTTING. 
 
 been used with fatal results. The best 
 generators have all of the seams and con- 
 nections welded. It would seem to reflect 
 upon the oxy-acetylene process to do other- 
 wise. 
 
 The motor which operates the feeding 
 machine should be strong and substantial. 
 If there is any possible chance of gears 
 in time stripping or breaking, devices 
 should be arranged to automatically lock 
 the motor. 
 
 PORTABLE GENERATORS. 
 
 There are some firms who advocate the 
 placing of an acetylene generator upon a 
 truck and using it for portable work. The 
 writer cannot condemn in too strong terms 
 such practice. There is no objection in 
 moving the generator when there is no car- 
 bide in it to where the work is to be done 
 and then charging the generator, but to 
 move a generator containing carbide and 
 water through buildings where there are 
 large insurable values is a great mistake 
 and is apt to result in loss of property and 
 possibly life. 
 
 DIRECTIONS FOR CONNECTING UP TANK OR 
 PORTABLE WELDING OUTFIT. 
 
 We shall take up first the installation 
 of a welding unit in which both the acety- 
 lene and the oxygen are used from tanks 
 
INSTALLING TANK OUTFIT. /5 
 
 or cylinders. These are known by the 
 trade as "tank" outfits. Before attempt- 
 ing* to light the torch, the novice should 
 thoroughly learn how the different parts 
 should be assembled, and he should know 
 the function of each separate part of the 
 equipment. 
 
 (1) With the portable or tank outfit it 
 is necessary to have two tanks. One of 
 these contains oxygen, and it is so stamped 
 or labeled. The other contains acetylene, 
 and this tank is plainly marked acetylene. 
 They are both gases, but have entirely dif- 
 ferent properties. Learn to call them by 
 their correct names of oxygen and acety- 
 lene. 
 
 (2) All oxygen tanks have a cap for 
 protecting the tank valve in shipment. 
 Eemove this cap by unscrewing and at- 
 tach the oxygen regulator, being sure that 
 the coupling nut is drawn up tight to pre- 
 vent leakage. It is impossible to attach 
 the wrong regulator as only the oxygen 
 regulator connection will fit the oxygen 
 tank valve. Then attach the oxygen hose 
 to the regulator outlet. 
 
 (3) If a Prest-0-Lite Acetylene tank is 
 used, an adapter must first be screwed in- 
 to the tank valve. This adapter has a left- 
 hand screw connecting to the tank. If 
 Commercial Acetylene or Searchlight tanks 
 
76 OXY-ACETYLENE WELDING & CUTTING. 
 
 are used the adapter is not necessary. 
 When outfit is ordered, you should specify 
 which make of acetylene tank you con- 
 template using so that the manufacturer 
 may furnish the right connection. If a 
 Prest-0-Lite tank is used, when the regu- 
 lator is connected it will be upright. If 
 Commercial or Searchlight tank is used 
 the regulator will form a right angle with 
 the tank. Be sure that the connection is 
 tight and well made so that there will be 
 no leaks. Then attach the acetylene hose 
 to the regulator outlet. 
 
 (4) Attach the oxygen hose to the cock 
 at the torch handle which is stamped with 
 the letter "0" or with the word oxygen. 
 With most torches this is the upper cock. 
 Then attach the acetylene hose to the cock 
 at the torch handle which is stamped with 
 the letter "A" or with the word acety- 
 lene. With most torches this is the lower 
 cock. 
 
 (5) The correct welding tip should be 
 selected and screwed tightly into the torch 
 head. Practically all manufacturers fur- 
 nish a table showing the size of tip that 
 should be used for different thicknesses of 
 metal. These tables are practically cor- 
 rect, but some latitude must be allowed, 
 as the mass of metal and the kind of metal 
 will necessitate some variation. 
 
INSTALLING. TANK OUTFIT. ( t 
 
 (6) Now see that the regulator screws 
 on both the acetylene and oxygen regu- 
 lators are entirely released that is, backed 
 out or turned to the left until they are free 
 of tension. 
 
 (7) SLOWLY open the oxygen tank 
 valve when the pressure and contents will 
 register on the dial of the 3000-lb. gauge. 
 
 (8) Open the acetylene tank valve and 
 the pressure of the gas in this tank will 
 register on the dial of the 500-pound gauge. 
 
 (9) Turn the acetylene regulator screw 
 to the right slowly until the number of 
 pounds pressure registered on the small 
 gauge is the same as shown in the manu- 
 facturer's table under the head of acety- 
 lene for that size of tip. This small gauge 
 indicates the acetylene pressure being de- 
 livered through the hose to the torch. 
 
 (10) Turn the oxygen regulator screw 
 to the right slowly until the number of 
 pounds pressure registered on the small 
 gauge is the same as shown in the manu- 
 facturer's table under the head of oxygen 
 for that size of tip. This small gauge in- 
 dicates the oxygen pressure being delivered 
 through the hose to the torch. 
 
 (11) Open the acetylene torch cock and 
 light the acetylene and then slowly open 
 the oxygen cock and continue to open until 
 the neutral flame is obtained. Occasionally 7 
 
78 OXY-ACETYLENE WELDING & CUTTING. 
 
 open or close one of the torch cocks to see 
 that proper flame regulation is being main- 
 tained. 
 
 (12) While operating should the flame 
 pop out, what is commonly called a "back- 
 flash" has occurred. This is caused by 
 one of three things: 
 
 First The tip becoming overheated. 
 
 Second A piece of molten metal flying 
 up and momentarily closing the 
 orifice of the tip. 
 
 Third By an insufficient amount of 
 pressure of either acetylene or 
 oxygen. 
 
 Should this occur, you should quickly 
 close first the oxygen torch valve and then 
 the acetylene torch valve. Then relight the 
 torch. 
 
 Sometimes in operating a welding torch 
 the smaller tips work correctly, but trouble 
 is experienced in getting the larger tips 
 to stay lighted. If upon investigation none 
 of the three troubles mentioned above are 
 responsible, then it is quite likely that dirt 
 has gotten in the torch tubes and partly 
 closed some of the openings. This dirt 
 can come from the hose or other causes. 
 By partly closing the openings they will 
 still be large enough to supply enough gas 
 for the smaller tips, but will not be large 
 enough for the larger tips. 
 
INSTALLING GENERATOR OUTFIT. 79 
 
 It will therefore, be necessary to attach 
 a hose to the tip end of the torch and by 
 using either compressed air or oxygen 
 from the tank blow the dirt out through 
 the handle. 
 
 DIRECTIONS FOR INSTALLING GENERATOR 
 WELDING OUTFIT. 
 
 GENERATOR INSTALLATION. 
 
 We now come to installation of a weld- 
 ing plant which uses acetylene from a gen- 
 erator instead of from a compressed tank. 
 The first question that suggests itself is 
 regarding the foundation. 
 
 GENERATOR FOUNDATION. 
 
 This may be of brick, stone, concrete, 
 iron or of wood. If of wood then it should 
 he of extra heavy timbers arranged so that 
 the air can circulate around them and ar- 
 ranged so as to form a substantial and firm 
 base. It should be seen that the generator 
 is level and that no unequal strain is placed 
 on it or any of the connections. 
 
 We would strongly recommend that 
 where possible the generator be placed 
 outside of insured buildings in properly 
 constructed generator houses. This is 
 greatly to be desired, particularly if the 
 insurable values are high, for the reason 
 that if the generator is located outside in a 
 separate detached building most, if not all, 
 
80 OXY-ACETYLENE WELDING & CUTTING. 
 
 of the states make no charge to the insur- 
 ance rates, whereas if the generator is lo- 
 cated inside of any of the main buildings 
 there is an increased premium rate. The 
 generator should be placed so that there 
 will be ample room both for the machine 
 and the attendant to perform his required 
 duties. Windows or skylights should be 
 provided so there will be no need for arti- 
 ficial light. In climates where there is 
 danger from freezing, proper protection 
 should be provided to guard against it. 
 Steam or hot water heat only should be 
 used. 
 
 ESCAPE OR VENT PIPES. 
 
 All generators of standard make are pro- 
 vided with an escape or vent pipe. This 
 should be of ample size, in no case to be 
 less than %-inch internal diameter. This 
 pipe should be installed without traps and 
 so that any condensation will drain back 
 to the generator. It must be carried to 
 a suitable point outside the building and 
 terminate in a hood located at least 12 
 feet from the ground. The hood must be 
 constructed in such a manner that it can- 
 not be obstructed by rain, snow, ice, insects 
 or birds. 
 
 CAPACITY. 
 
 Generators should be of sufficient ca- 
 pacity to furnish gas under working con- 
 
PIPING. 81 
 
 ditions from one charge of carbide to all 
 torches installed, for at least one working 
 period of one-half day or 4y 2 hours. For 
 the better class of machines carbide feed 
 the rating has been fixed at one cubic 
 foot of gas per hour, per pound of carbide. 
 As an example a 50-pound machine, that 
 is; one having a capacity of 50 pounds of 
 carbide per charge, would have a rated 
 capacity of 50 cubic feet of acetylene per 
 hour. 
 
 PIPING. 
 
 Connections from the generator to serv- 
 ice pipes should preferably be made with 
 right and left couplings or long thread 
 nipples with lock nuts, Where unions are 
 used these should be of a type which obvi- 
 ates the necessity for using gaskets. Where 
 possible, the piping should be arranged so 
 that any moisture will drain back to the 
 generator. If low points necessarily oc- 
 cur in any piping, it should be drained 
 through tees into drip cups permanently 
 closed with screw caps or plugs. In no 
 event use pet-cocks. 
 
 In large installations where the service 
 pipe extends a considerable distance, thej 
 main service pipe should be broken at a ( 
 point as close to the generator as possible. ] 
 The connection here should be made out 
 of strong and substantial rubber hose. Thej 
 
82 OXY-ACETYLENE WELDING & CUTTING. 
 
 object of this rubber hose is to secure 
 electrical insulation] Some accidents have 
 occurred by reason of electricity used in 
 the plants grounding on the acetylene serv- 
 ice pipe and causing a spark while the 
 generator was being charged. Insulation 
 as recommended above will prevent this. 
 
 The schedule of pipe sizes for piping 
 from the generator to torches should con- 
 form to that commonly used for ordinary 
 gas, but in no case must feeders be smaller 
 than %-inch. 
 
 Generators should not be directly con- 
 nected to sewers, but should discharge into 
 suitable open receptacles which may be 
 provided with an overflow pipe connected 
 to the sewer. Piping should be carefully 
 tested when system is completed. It must 
 not show a loss in excess of 1 pound with- 
 in 12 hours when subjected to a pressure 
 of 8 pounds. 
 
 CARE AND MAINTENANCE. 
 
 Generators should be cleaned and re- 
 charged as nearly as possible at regular 
 stated intervals. This work, as well as 
 any repairs, should be done during daylight 
 hours only when artificial light is not 
 needed. When artificial light is absolute- 
 ly necessary, this must be provided by in- 
 candescent electric lights enclosed in gas 
 tight globes. In charging generator clean 
 
MAINTENANCE. 80 
 
 all of the residue out thoroughly, and then 
 fill with the required amount of water. 
 Never charge with carbide unless generator 
 is filled with water. Always keep flash- 
 back chamber filled with watef. 
 
 CONNECTING REGULATORS. 
 
 When the generator and the service pip- 
 ing leading therefrom has been installed, 
 attach the acetylene generator regulators 
 to the piping at the various locations pre- 
 viously determined as welding stations. 
 Connect the acetylene hose to the regulator 
 Individual oxygen tanks can be used at 
 the various welding stations or a number 
 of oxygen tanks can be connected to a 
 manifold provided with a regulator -and 
 the gas piped at a reduced pressure wher- 
 ever required. Connecting the torch is 
 the same as for the tank plant. 
 
 A FEW DON'TS. 
 
 Never recharge generator without first 
 cleaning out the generating chamber and 
 completely refilling with water. 
 
 Never test the generator or piping for 
 leaks with a flame, and never apply flame to 
 any open pipe or at any point other than 
 the torch. In testing for leaks use soap 
 and water. 
 
 Never use a lighted match, lamp, candle, 
 lantern or any open light near the gen- 
 erator. 
 
CHAPTER V. 
 
 PREPARING FOR WELDING. 
 TOOLS NECESSARY FOR REPAIR 
 
 WELDING. 
 
 Probably 90% of those who purchase 
 welding apparatus already have all neces- 
 sary tools for the welding shop, but for 
 the benefit of the remaining 10% we would 
 say that one should have a vise, clamps, 
 files, stillson and monkey wrenches, tongs, 
 chisels, hammer, forge, stationary emery 
 and if possible a portable one also, chain- 
 block, V-blocks, square and stiaight edge, 
 portable kerosene torch, a number of 
 small pieces of iron or steel ranging in 
 thickness from that of a saw-blade on up, 
 to be used as shims, hack-saw, about 200 
 fire brick, roll of asbestos paper, and a 
 welding table. 
 
 The welding table is the only accessory 
 that requires a description. If one is in 
 a town where there is a scrap-iron dealer, a 
 cheap and serviceable table can usually be 
 found in his scrap pile and obtained for 
 the price of ordinary junk. If possible, 
 secure an old casting that has been ma- 
 chined on one side and is at least two or 
 three inches thick so that it will not be 
 easily warped by the heat. An old planer 
 
 84 
 
CLEANING AND BEVELING. 85 
 
 bed makes an excellent table if you should 
 be fortunate enough to find one. If it is 
 impossible to procure such a casting, then 
 it will be necessary to make a table about 
 30 inches high of either angle iron or bar 
 stock and cover it with brick. 
 
 CLEANING THE METAL. 
 
 The edges to be welded and the immedi- 
 ate vicinity of the weld should be thorough- 
 ly cleaned. Not only will the welding be 
 facilitated by doing so, but it also prevents 
 the dirt, oxide, etc., from being incorpo- 
 rated in the molten metal and assisting if 
 not actually forming blow-holes. 
 
 If the work is well cleaned, less flux will 
 be required and that which is used will do 
 its work better. 
 
 BEVELING. 
 
 Where the metal to be welded is of a 
 thickness of 3/16 of an inch or more, the 
 edges should be beveled so that when the 
 two pieces are placed together they form 
 an angle of at least 90 degrees. 
 
 In steel of % of an inch in thickness or 
 more this bevel should be of an even great- 
 er angle. 
 
 Beveling can be accomplished by either 
 grinding, chipping or sawing and it is 
 necessary for several reasons. By remov- 
 ing the metal, this allows the flame to get 
 
86 OXY-ACETYLENE WELDING & CUTTING. 
 
 down to the bottom and work its way up 
 and it permits of adding a greater quanti- 
 ty of metal of better quality. Some weld- 
 ers do not bevel, but depend upon the torch 
 to flow the metal out or they dislodge it 
 when molten by means of a rod. 
 
 In the great majority of cases this is 
 bad practice. Occasionally where it would 
 be difficult to "line up" the casting after 
 it was ground, beveling may be dispensed 
 with. Those welders who make a practice 
 of welding without beveling will be very 
 apt to be troubled with "come-backs" and 
 an examination of their work will deter- 
 mine that they have not welded all the way 
 through, or that they have burned the 
 metal. 
 
 When the part to be welded is % of an 
 inch thick or more, it is best to bevel and 
 weld on both sides if it is possible to do so. 
 
 PRE-HEATING METHODS AND DEVICES. 
 CHARCOAL. 
 
 Probably the first method of pre-heating 
 was the use of charcoal. This fuel is still 
 used to a considerable extent. It has the 
 advantages of a slow heat, an even one 
 and a fairly high temperature. The slow 
 heat, while an advantage on some castings 
 is a disadvantage on others. There is one 
 serious objection and that is the disagree- 
 
PRE-HEATING FUELS. 87 
 
 able fumes which accompany its combus- 
 tion. 
 
 ARTIFICIAL OR NATURAL GAS. 
 
 In the cities and in certain sections of 
 the country, it is possible to procure one 
 of the above gases. Where gas can be ob- 
 tained, this makes an ideal fuel for pre- 
 heating when used in connection with prop- 
 erly designed torches. The inlet service 
 main into the building should be sufficiently 
 large to furnish an adequate flow of gas. 
 This pipe should not be less than 2 inches 
 in diameter. For cylinder work, or where 
 the pre-heating is primarily to take care 
 of expansion and contraction a torch us- 
 ing the gas with ordinary atmosphere air 
 is best adapted. This torch is constructed 
 on the Bunsen burner principle and is sold 
 by almost all manufacturers of welding ap- 
 paratus. A torch of this kind gives a soft 
 flame of not too concentrated a heat. 
 
 If the pre-heating is entirely or mainly 
 for the purpose of economy in the use of 
 acetylene and oxygen, then the gas should 
 be burned with a torch using compressed 
 air. When used with compressed air a 
 more concentrated flame of higher tem- 
 perature is secured just the thing for 
 work of this character. 
 
88 OXY-ACETYLENE WELDING & CUTTING. 
 
 Torches of either of the two types are 
 made in different sizes and the consump- 
 tion of gas will range from 100 to 200 cubic 
 feet per hour. At $1.00 per 1000 cubic 
 feet, they will cost from lOc to 20c per 
 hour. 
 
 Fi.u". S. 
 Kerosene Pre-Heating Torch 
 
FEE-HEATING FURNACES. 89 
 
 KEROSENE AND GASOLINE TORCHES. 
 
 For outside or portable work one of the 
 above torches is very desirable. They are 
 not well adapted for expansion and con- 
 traction pre-heating, their field being large- 
 ly that of heating up heavy castings in 
 order to save in the use of acetylene and 
 oxygen. Compressed air, usually obtained 
 by a hand pump, is used with either fuel. 
 The kerosene torch will be found to be 
 more economical fo operate and will give 
 a higher temperature. These torches are 
 also manufactured and sold by the leading 
 welding manufacturers. 
 
 FURNACES FOR PRE-HEATING. 
 
 We have seen the different fuels that 
 can be used for pre-heating castings pre- 
 paratory to welding. Now the casting is not 
 heated out in the open for the reason that 
 there would be too great a loss of heat and 
 the casting would be subjected to the di- 
 rect influence of drafts. It has been found 
 necessary when heating the casting to en- 
 close it in either a temporary or a perma- 
 nent furnace. There are a few who advo- 
 cate the use of a permanent furnace, but 
 unless this work is all of the same size the 
 extra outlay for such a furnace is a use- 
 loss expense; besides, they are usually ex- 
 travagant with fuel. The most practical 
 
90 OXY-ACETYLENE WELDING & CUTTING. 
 
 and economical furnace is a temporary one 
 built from loose fire brick, whether char- 
 coal, gas or kerosene fuel is used. 
 
 The bricks are simply laid one upon the 
 other, leaving a space of from 6 to 12 inches 
 around the casting, depending upon its size. 
 If charcoal is used, the bricks are spaced 
 near the bottom, leaving cracks through 
 which the air which feeds the fire can pass. 
 The top is covered with sheet iron or as- 
 bestos. If gas is used s'pacing of the brick 
 is not necessary, the only openings required 
 being those through which the gas torches 
 pass. If the heating is to take care of ex- 
 pansion and contraction, the gas torches 
 should not be turned directly on the cast- 
 ing, but should be made to impinge direct- 
 ly on the brick. This will cause the flame 
 to whip around the casting and thereby 
 secure a more even heat. If the primary 
 object of the heating is a saving of acety- 
 lene and oxygen then the pre-heating torch 
 can play directly on the casting. 
 
 EXPANSION AND CONTRACTION. 
 
 All metals are affected by heat. The 
 action of heat produces an increase in 
 volume ; that is, a casting when heated has 
 greater length, breadth and thickness. This 
 is called expansion and as a general prop- 
 osition this expansion increases progres- 
 sively as the temperature increases. As 
 
EXPANSION. 91 
 
 the casting cools itfe volume begins to get 
 less, until at normal temperature it usually 
 assumes its original size. This is called 
 contraction. It is well to remember that 
 you cannot stop a casting from expanding 
 when it is heated. This force is irresist- 
 ible; no power can prevent it. Do not 
 attempt to prevent a casting from expand- 
 ing by means of clamps. If you should be 
 so foolish as to try, and the clamps were 
 strong enough, distortion of the casting 
 would inevitably result. As most castings 
 are of irregular shape, and the metal usual- 
 ly varies in thickness, it is necessary to take 
 some precautions in heating so that the 
 heavy parts will expand in the same ratio 
 as the thin parts. If this is not done either 
 breaking or distortion is very apt to occur. 
 This precaution is uniform heating and in 
 order to secure a uniform heat sloiv heating 
 is necessary. For pre-heating of cylinders 
 and like castings in order to take care of 
 expansion, remember to heat slowly and 
 uniformly and of course to take care of 
 contraction cool slowly and uniformly.' 
 That is the "meat in the cocoanut," heat- 
 ing slowly and uniformly and cooling slow- 
 ly and uniformly. When the foundryman 
 made the casting it was poured from molten 
 metal possessing the same temperature 
 throughout and flowed into a mold where 
 
92 OXY-ACETYLENE WELDING & CUTTING. 
 
 it was entirely protected from the air by 
 the sand, which permitted an even and uni- 
 form cooling. Welding with the oxy-acety- 
 lene flame is simply re-casting and the 
 beginner would do well to study and follow 
 foundry practice in a number of instances. 
 Unless the beginner studies and thor- 
 oughly understands the principles of ex- 
 pansion and contraction and applies it to 
 the work at hand he will not be a success, 
 regardless as to how*well he may manipu- 
 late the torch. In the majority of cases it is 
 just as important to maintain alignment 
 as it is to make a good weld. If the welder 
 ignores expansion and contraction, it is in- 
 evitable that one of three things will hap- 
 pen: 
 1st The casting on cooling will break in 
 
 or near the weld. 
 2nd Distortion of the work destroying 
 
 alignment. 
 
 3rd The weld may not break and distor- 
 tion may not occur, but there will 
 be a strain in the casting, causing the 
 welded portion, or near it, to snap 
 and break when the load is placed 
 on the machine. 
 
 A good way to illustrate the effects of 
 expansion and contraction and one appar- 
 ently popular with those writing on the sub- 
 ject is represented by Figures 9, 10, 11 
 
CONTRACTION. 
 
 93 
 
 and 12. Figure 9 represents a bar 
 which is broken at "A." In this case 
 the weld can be made without giv- 
 ing any attention to expansion and con- 
 traction in view of the fact that the 
 ends "B" are free. Of course, while 
 
 I 
 
 >7 
 
 Fig. 9. 
 
 being welded the heat will expand it, but 
 there is nothing holding it and it can in- 
 crease its length as well as its breadth and 
 thickness, and when it cools it comes back 
 into its original position. Now in Figure 
 10, B A B represents the same bar, except 
 
 B 
 
 Fig. 10. 
 
 that now it is the middle member of a 
 frame. The length, breadth and thickness 
 is the same, the break is the same as is 
 also the location. The only difference is 
 that the ends "B" are now a part of the 
 
94 OXY-ACETYLENE WELDING & CUTTING. 
 
 sides C B D. Let us assume that we make 
 the weld exactly as we did when the bar 
 was not a part of the frame. 
 
 1 
 
 
 
 
 
 
 
 
 
 
 1 
 
 1 f* 
 
 
 
 
 B \ t 
 
 9 
 
 
 
 \ 1 
 
 
 
 
 
 
 Fig. 11. 
 
 No difficulty would be experienced in 
 making the weld, but upon cooling it would 
 probably break. However, if it did not 
 break and we sight down the edge C B D 
 
 c ^^ c 
 
 JL 
 
 Fig. 12. 
 
 it will appear to be "sway-backed" and if 
 we place a straight edge along this surface 
 (Fig. 11) we can easily see that it does not 
 touch at "B" and is somewhat concave. 
 
MELTING POINTS OF METALS. 95 
 
 Now when the weld at "A" cooled, BAB 
 became shorter by reason of contraction 
 and being stronger than C B D it pulled 
 these two sides in. The casting is not only 
 warped and out of alignment, but a con- 
 siderable strain is also set up. It must be 
 plain that considerable power was required 
 to bend C B D and this tension is what is 
 known as the strain. The proper way to 
 make this weld is shown in Fig. 12. 
 
 The ends "C" and "D" are heated and 
 expand and the break at "A" opens. We 
 can now proceed to make the weld without 
 fear of bad results. The ends "C" "D" 
 and the weld "A" all cool down together, 
 leaving the casting in alignment and with- 
 out a strain. 
 
 This is perhaps the simplest illustration 
 that could be given of expansion and con- 
 traction. Each case must be studied. Some 
 experimenting will have to be done and 
 some failures will be recorded. A good 
 rule to follow is " When in doubt pre-heat 
 the entire casting.'' 
 
 MELTING POINTS' OF METALS. 
 
 While it is not necessary to know the 
 various melting points of metals and alloys 
 in order to do good welding, such informa- 
 tion will likely prove interesting and in- 
 structive. 
 
96 OXY-ACETYLENE WELDING & CUTTING. 
 
 Melting Melting 
 
 Metal Point Metal Point 
 
 Platinum 3200 F. Silver 1750 F. 
 
 Soft Steel 2700 F. Brass 1700 F. 
 
 Hard Steel 2550 F. Bronze 1650 F. 
 
 Nickel 2500 F. Aluminum 1200 F. 
 
 Cast Iron 2100 F. Zinc 850 F. 
 
 Red Copper 1900 F. Tin 650 F. 
 
 Authorities differ considerably as to the 
 above temperatures. We have taken the 
 figures of several and arrived at a mean 
 temperature which should be sufficiently 
 correct for comparative purposes. 
 
 REGULATION OR ADJUSTMENT OF THE FLAME. 
 
 Elsewhere we have shown how to as- 
 semble the welding unit and how to light 
 
 Fig. 13. 
 Acetylene Only Burning-. 
 
 the torch. The next and one of the most 
 important things is the question of adjust- 
 ment so that a neutral flame will be ob- 
 tained and maintained. The acetylene 
 should be lighted and as the acetylene torch 
 cock is slowly opened, it will be seen that 
 the flame jumps a very slight distance 
 away from the end of the tip when using 
 a small size, and as the size of the tip in- 
 creases this space increases likewise, until 
 
REGULATION OF FLAME. 97 
 
 in a very large tip the flame will be sepa- 
 rated from the end of the tip by possibly 
 3/16 of an inch. We now turn on the oxy- 
 gen by slowly opening the torch cock. The 
 first thing we notice is that the entire flame 
 assumes a more brilliant and whiter color. 
 A slight increase in the oxygen and we see 
 that the end of the flame commences to 
 take on a yellowish cast and the white sec- 
 tion is shortening. A further increase in 
 the amount of oxygen tends to increase the 
 
 Fig. 14. 
 Excess of Acetylene. 
 
 amount of yellow and diminish the amount 
 of white. We have now what is known as 
 a carbonizing flame. By that is meant that 
 there is not enough oxygen. The white por- 
 tion has what is commonly called a "rag- 
 ged" edge. If welding is done with this 
 kind of a flame the metal is almost sure 
 to be hard and difficult to machine. We 
 slowly further increase the amount of oxy- 
 gen and as we do so, we can see the white 
 portion drawing within itself or shorten- 
 ing up. When the last straggling edge dis- 
 appears and the white cone is round and 
 well defined, it is then we have the much 
 
98 OXY-ACETYLENE WELDING & CUTTING. 
 
 talked of neutral flame. The length of this 
 small white cone should be about 2 l / 2 times 
 its diameter. This is the proper flame for 
 welding. If the oxygen is further increased 
 the white cone shortens, becomes more 
 pointed and the hissing sound of the gas 
 escaping is materially increased. 
 
 Fig. 15. 
 Correct or Neutral Flame. 
 
 This is what is called an oxidizing flame. 
 By that is meant too much oxygen is being 
 furnished and the work is sure to be 
 burned. 
 
 Fig. 16. 
 Excess of Oxygen. 
 
 The beginner should practice lighting 
 his torch for an hour or more. A hun- 
 dred times he should light his torch, adjust 
 the flame, turn off the gas and relight 
 again, until he is absolutely satisfied that 
 he knows what a neutral flame is and how 
 to procure it. 
 
 When the neutral flame is once secured 
 
HOW TO MAKE A WELD. 99 
 
 it does not follow that it will continue 
 neutral indefinitely. On the contrary it 
 will quite likely vary somewhat. This will 
 instantly be detected by the experienced 
 welder by its effect on the metal. How- 
 ever, this treatise is intended primarily for 
 the beginner the neophyte and not for 
 the experienced, and so the thing to do is 
 every now and then test the flame by 
 slightly closing the oxygen torch valve 
 until the flame is carbonizing, and then 
 again slowly opening it up until a neutral 
 flame is obtained. The trade speaks of the 
 small, blue-white flame as the "cone" and 
 of the outer flame as the "envelope." It 
 is well that one should know these terms 
 and speak of them properly. 
 
 EXECUTION OP A WELD. 
 
 We have already told how to install a 
 welding outfit, how to light and regulate 
 the torch and how to set up or prepare the 
 work. The next thing is how to execute a 
 weld. Whether the welder sits or stands 
 upright is of no importance. 
 
 The torch is held firmly, but not rigidly, 
 and a steady hand is of prime importance. 
 Welding should progress forward in a di- 
 rection away from the operator. The angle 
 at which the torch should be held depends 
 upon the thickness of the metal, but for the 
 
100 OXY-ACETYLENE WELDING & CUTTING. 
 
 average class of work a slightly inclined 
 forward position is the one that will be 
 found best. For light sheet metal work 
 where no filler rod is nsed the angle of 
 inclination becomes less, whereas for heavy 
 work the torch will be held almost per- 
 pendicular to the work. 
 
 In welding the torch should not be di- 
 rected upon a particular spot for any great 
 length of time, but should move slightly 
 so that the flame will come in contact with 
 other parts in the immediate vicinity. This 
 should not be understood to mean that the 
 torch should sweep a circle whose diameter 
 is one or two inches. Most beginners make 
 this mistake. 
 
 The torch should be moved not more 
 than % or 5/16 of an inch at a time for 
 average work say %" or ^" in thickness. 
 A circular motion for metal of this thick- 
 ness is not essential, but it is well to 
 acquire it. For sheet metal work this 
 circular movement is very desirable, 
 producing a very smooth and pretty 
 weld. However, there are some that prefer 
 an oscillatory movement, the torch being 
 pushed like a pendulum from one side of 
 the sheet to the other while advancing in 
 a forward direction. So far we have not 
 referred to the welding rod. It should be 
 held in the free hand. Instead of using a 
 
SIZE FILpTv TO USE. 101 
 
 straight rod, it will J be found itiore 'coii- 
 venient for the welder to use a rod having 
 an angle of 90 degrees. In steel this is 
 formed by simply bending over 3 or 4 
 inches of the end and continuing to do this 
 as the rod is used up. For cast iron, we 
 hold the end of one rod in the middle of 
 another and "tack" the two with the torch. 
 The size of the welding rod is important 
 and should be proportional to the thickness 
 of the metal welded. 
 
 The following table will be a fair guide 
 to follow : 
 
 Dia. ofWeld'g 
 
 Rod for Dia. of Weld'g 
 
 Thickness Cast Iron Rod for Steel 
 
 of Metal No. 12 
 
 No. 16 to 1<8 Gauge Gauge Wire 
 
 i/ 8 in. to 1,4 in. i/ 8 in. i/ 8 in. 
 
 14 in. to & in. & in. & in. 
 
 % in. to 1/2 in. ^ in. -& in. 
 
 1/2 in. to % in. % in. % in. 
 
 % in. to % in. & in. % in. 
 
 Most beginners make the fatal mistake 
 of not getting the metal to be welded hot 
 enough before adding the filler rod. It is 
 a good plan in beginning a weld to forget 
 that you have a filler rod. Get the casting 
 hot and then start the metal to flowing to- 
 gether at tlie bottom of the bevel. Not un- 
 til then should the filler be used. The 
 edges of the weld and the filler rod must 
 
10$ , OXV-Ar r KTTLENE WELDING & CUTTING. 
 
 melt dt the same time. If this is riot done, 
 the weld will be of no value. 
 
 The welding rod should not be held so 
 that as the metal melts it falls in drops 
 on the weld. In a great deal of work the 
 welding rod is held against the welded por- 
 tion practically at all times. Where this 
 is not done, the rod is held so that the 
 outer flame of the torch or the envelope 
 will keep it hot, so that when the moment 
 arrives for adding on some metal, the rod 
 is lowered into the molten metal. By this 
 time the end of the rod should be melting, 
 but it may be necessary to direct the torch 
 against the rod. A small amount of metal 
 is added and then the edges of this added 
 metal should be melted and made to inti- 
 mately incorporate with the main body of 
 metal. A very important thing to bear 
 in mind is the distance the torch should 
 be held from the metal. For steel welding 
 the end of the white cone should just touch 
 or brush the metal. For cast-iron it should 
 not touch the metal but should be held 
 about 3/16 of an inch from it. Sometimes, 
 in order to work out blow-holes that are 
 the result of impurities burning to a gas, 
 it may be necessary to push the end of the 
 white cone down into the molten metal 
 and with a slight rotary motion flirt out 
 the impurities. 
 
CHAPTER VI. 
 
 WELDING OF DIFFERENT METALS. 
 CAST-IRON WELDING. 
 
 Probably 75% of the welding done in a 
 custom repair shop is the welding of cast- 
 iron. Contrary to popular belief, it is the 
 easiest welding to learn ? and when care and 
 good workmanship are exercised the 
 welded portion will be superior to the rest 
 of the casting. The failures that occur are 
 usually on pieces such as cast-iron boiler 
 sections where the life of the metal has 
 been burned out on account of long contact 
 with a fire, or on work where expansion and 
 contraction are difficult to take care of. 
 
 Cast-iron is an alloy of steel and carbon. 
 The carbon contents vary from 3% to 5%, 
 and it exists in two states : first, as a chemi- 
 cal mixture and, second, in a free state. 
 In the latter case the carbon is distributed 
 throughout the iron in much the same way 
 that salt is placed in bread. Upon the 
 amount of free carbon in the cast-iron will 
 depend the softness of the metal and, of 
 course, the ease with which it can be ma- 
 chined. 
 
 HARD SPOTS. 
 
 The bugbear of the average beginner is 
 hard spots in cast-iron welding. By ob- 
 
 103 
 
104 OXY-ACETYLENE WELDING & CUTTING. 
 
 serving a few rules this trouble can be 
 practically overcome. The important rules 
 to be remembered and observed ar^e: 
 
 First, see that a neutral flame is main- 
 tained at all times. 
 
 Second, keep the white cone about *4 of 
 an inch from the metal. 
 
 Third, use a clean, high-grade welding 
 rod, free from dirt and with a silicon con- 
 tent of about 3%. 
 
 Fourth, use only enough flux to make 
 the metal flow and insist on a flux free 
 from carbonates. 
 
 Fifth, cool the work slowly. 
 
 Even with all of these precautions fol- 
 lowed, occasionally one will have a few 
 ha^d spots. Usually these are on the sur- 
 face and can be easily removed with an 
 emery, but if any difficulty in doing this 
 presents itself the following, which was 
 recommended by an old blacksmith, may be 
 tried: Place some powdered sulphur on 
 the weld by means of an old hack saw blade 
 or flat file and rub the sulphur on the weld 
 until the suphur ceases to burn and be- 
 comes gummy ; then cool slowly. While we 
 know there are some objections to this, 
 still it has been tried by the writer and 
 while not infallible, it frequently helps. 
 
 It is necessary to weld cast-iron in a 
 horizontal position. This is because it has 
 
HARD SPOTS. 105 
 
 no tenacity when molten. Sometimes it 
 becomes necessary to make a vertical weld, 
 in which case a heavy piece of steel or a 
 fire brick is used to form a shelf. As the 
 welding progresses, the shelf is raised or 
 built up higher. As previously stated, the 
 edges of the metal at the weld should be 
 beveled except for very thin metal. 
 
 Only first-class welding rods should be 
 used. These should be purchased from 
 those specializing in oxy-acetylene appara- 
 tus and who guarantee to flame-test their 
 welding materials. It is to be deplored 
 that at the present time there seems to be 
 a tendency to buy on a price rather than 
 a quality basis. It is the very poorest 
 economy to buy cheap welding materials. 
 
 In using the flux, the welding rod is 
 heated and dipped into the can when 
 enough should adhere to the rod. If the 
 iron is unusually "dirty," it may be found 
 advisable to sprinkle some flux on the weld 
 with the fingers, but too much should not 
 be used. 
 
 Sometimes the operator has trouble pre- 
 venting the metal from running away when 
 trying to square up a casting. In cases 
 of this kind, the torch should be turned 
 over so that the flame will be pointed up. 
 The force or blast of the flame will help 
 to hold the metal and prevent its running 
 
106 OXY-ACETYLENE WELDING & CUTTING. 
 
 away. But this alone will not do. By 
 watching the metal closely one can see when 
 it is about ready to topple over and run 
 down and just before this happens lift 
 the torch and give the metal a chance to 
 set. Then go back and add a few more 
 drops and in a very short time enough 
 metal has been added and the edge is 
 squared up. All that is necessary is pa- 
 tience and practice. 
 
 BLOW HOLES. 
 
 One source of considerable annoyance to 
 the beginner is the formation of blow- 
 holes in the weld. These could just as well 
 be called gas holes, as they are caused 
 Cither by the absorption of gases or by 
 impurities in the metal burning to a gas, 
 probably more often the latter. They will 
 form with the good w r elder and the poor 
 welder alike, but the difference lies in the 
 fact that the good welder will get rid of 
 the blow-holes, whereas the inexperienced 
 permits them to remain in the weld. How 
 does the good welder get rid of them! 
 
 Most beginners and also a great many 
 who have had considerable experience get 
 the surface of the casting flowing a little 
 and then add a heavy layer of cast-iron 
 from the filler and then attempt to "work 
 in" this heavy addition. The mistake is 
 
BLOW-HOLES. 107 
 
 flowing iii too much metal at one time. Not 
 only on cast-iron, but on any kind of weld- 
 ing never add any more metal than is 
 necessary. One should add a very thin 
 layer at a time, putting it in the right 
 place and leaving it there. A slight but 
 constant motion of the filler rod and the 
 torch should be maintained until the weld 
 is finished. The filler rod should be dipped 
 into the flux quite frequently and when a 
 thin layer is added, lift the torch for a 
 second or two and allow it to solidify be- 
 fore adding any more. By doing this, you 
 allow to escape the gases which otherwise, 
 as in case of a heavy addition of filler, are 
 covered over and enclosed and are unable 
 to break through the heavy layer of metal. 
 
 In the making of bread, lightness is de- 
 sired. This lightness or porosity is ob- 
 tained by the formation of gas, and its re- 
 tention in the bread until -baked or solidi- 
 fied, producing a multiplicity of blow-holes. 
 If for any reason the gas escapes, the bread 
 drops, becomes heavy and compact, some- 
 thing to be regretted in bakeries, but the 
 very thing we are trying to do with the 
 cast-iron allow the gas to escape so that 
 it will be compact, close-grained and free 
 from blow-holes. 
 
 In welding of large castings that have 
 had to be pre-heated, or even those the 
 
108 OXY-ACETYLENE WELDING & CUTTING. 
 
 size of automobile cylinders, the work is 
 attended with considerable discomfort on 
 account of the heat. We would recommend 
 the nse of a portable electric fan. This 
 can be set on a box and pointed so that 
 the blast of air is in an upward direction, 
 just in front of the welder. It is needless 
 to say that the current of air should be 
 turned so that it will not strike the casting. 
 By using a fan the operator will at all 
 times be supplied with fresh air free from 
 any fumes and will be kept cool, a condi- 
 tion that enables him to turn out more 
 work than otherwise. It is not only hu- 
 mane, but it will be found to be good busi- 
 ness practice to furnish a fan. 
 
 WELDING OF STEEL. 
 
 For the average welder, steel may be 
 divided into two classes soft steels and 
 hard steels. The difference between these 
 two is mainly that of carbon content. In 
 the soft steels the carbon content may be 
 as IOAV as .05 per cent, while extremely 
 hard steels may contain as much as 1.5 
 per cent of carbon. Low carbon or soft 
 steels have high ductility and malleability. 
 
 Increasing the carbon contents increases 
 the strength, elastic limit and the property 
 of being hardened by tempering. The soft 
 steels are the easiest welded, while the 
 
STEEL WELDING. 109 
 
 hard steels, particularly if the metal is 
 over one inch in thickness, are the most 
 difficult. Operators quickly learn to do 
 beautiful work on thin sheets of soft steels, 
 but they are lost when attempting heavy 
 work. Unquestionably the welding of 
 medium and heavy steel is the most diffi- 
 cult to learn. 
 
 The average welder does not get his 
 metal hot enough or he gets it too hot and 
 burns it or oxidizes it, as the chemist would 
 say. Of course, it is a comparatively easy 
 matter to overcome the first shortcoming 
 by increasing the size of the welding flame 
 or by playing the flame on the metal for a 
 longer time, but the second fault of burn- 
 ing the metal is not so easy to avoid. It 
 is practically impossible to prevent this, 
 using a torch of poor design supplying an 
 excess of oxygen to the flame. We have 
 already emphasized the importance of 
 using scientifically designed torches, but 
 it will bear repetition. As oxygen is always 
 present in the air, this atmospheric oxygen 
 will greedily attack the steel when in a 
 heated condition. All of us are familiar 
 with the scale that forms on steel when 
 heated in an open fire. This scale is simply 
 oxidized iron or burnt metal. If this oxide 
 is allowed to incorporate itself with the 
 weld, the strength is bound to suffer. 
 
110 OXY-ACETYLENE WELDING & CUTTING. 
 
 It would almost seem superfluous to 
 again impress upon the beginner the im- 
 portance of flame regulation, did not ne- 
 cessity demand it. An excess of acetylene 
 carbonizes the metal, while an excess of 
 oxygen burns it. 
 
 The importance of using a good welding- 
 wire is usually underestimated. Swedish 
 wire has long been advocated and it is 
 excellent, but we doubt at the present time 
 whether there is any genuine wire of this 
 kind in this country. This does not mean 
 that excellent domestic welding wi re is not 
 to be had. On the contrary our country 
 produces as fine welding wire as any na- 
 tion. The impression prevailed for a long 
 time that Swedish iron's reputation was 
 based on the fact that it was made with 
 high-grade charcoal, but recent investiga- 
 tions have exploded this belief. We know 
 now that the strength and tenacity of 
 Swedish iron is due to the fact that cen- 
 turies ago Mother Nature deposited with 
 the iron ore a small percentage of vanadi- 
 um, and when the ore was smelted, this 
 vanadium, scavenger like, cleansed the 
 metal of its impurities and thereby im- 
 parted those properties which have given 
 it its reputation. 
 
 Some American firms, grasping at any- 
 thing that will help them to dispose of their 
 
STEEL WELDING. Ill 
 
 wares easily, have coined trade names in 
 which a part of the name Sweden is used, 
 by which they designate their wire. Oft 
 the face of it, it is designed to deceive and 
 mislead the public. 
 
 Acting on the knowledge we have as to 
 the properties of vanadium, several years 
 ago the writer, in conjunction with one 
 of the large steel companies, experimented 
 and finally produced a rod containing a 
 low percentage of vanadium and carbon 
 which for heavy welding is unsurpassed. It 
 must be remembered that there are many 
 kinds of vanadium steel on the market and 
 only one kind is suitable for a filler rod. 
 
 There are some writers who advocate the 
 hammering of the metal after welding. 
 This probably does do some good if the 
 operator is able to determine the correct 
 temperature at which the metal should be 
 and is capable of maintaining this tem- 
 perature, otherwise more harm than good 
 will be done. 
 
 The exact temperature at which ham- 
 mering should be done is difficult for the 
 novice to either determine or obtain, and 
 our advice is to learn to rely upon the 
 welding alone. 
 
 The welding of hard steels is difficult 
 even for an experienced welder and the 
 beginner had better not try' this class of 
 
112 OXY-ACETYLENE WELDING & CUTTING. 
 
 work. The work is best done if the entire 
 piece or at least a considerable portion of 
 it is pre-heated to a cherry red and a tip 
 selected that is one size larger than if the 
 work was soft steel. If anything, the flame 
 should be slightly carbonizing. The weld- 
 ing should be done fast. One should not 
 linger over the work, as this will burn the 
 metal. 
 
 WELDING OF BRASS OR BRONZE. 
 
 Brass is an alloy of copper and zinc, 
 while bronze is an alloy of copper and tin. 
 With the exception of the cheap brasses, 
 that is, those having a high percentage of 
 zinc, either brass or bronze can be welded 
 with good success. When hot, considerable 
 care should be exercised, if it is necessary 
 to move the work, as neither one of the 
 two alloys has much strength then and the 
 least strain will cause the casting to break. 
 
 The work should be beveled and the 
 edges and immediate vicinity of the weld 
 thoroughly cleaned. 
 
 A welding tip one size larger than is 
 necessary for the same size work in cast- 
 iron should be employed. Pre-heating is 
 justified on the grounds of economy. The 
 white cone should be held a distance of 
 about i/i" from the metal. Just back of 
 the weld on both sides should be heated 
 
BKASS WELDING. 113 
 
 thoroughly, and some flux sprinkled in the 
 groove. The torch is then switched to 
 the beveled edges and as the edges com- 
 mence to melt add the filler rod of either 
 Tobin or manganese bronze, first dipping 
 the heated rod in the flux. If the weld is 
 a tooth in a gear or located at some wear- 
 ing point, manganese bronze is preferable 
 as it is somewhat harder, otherwise use 
 Tobin bronze. 
 
 Weld fast or you will find blow-holes in 
 your work due to the zinc and tin burning 
 out and the metal absorbing gases. 
 
 WELDING OF COPPER. 
 
 The melting point of copper is not only 
 high, but it also conducts the heat very 
 rapidly and these two properties combine 
 to make it a metal very difficult to weld 
 properly. In addition it absorbs gases 
 from the welding flame, which causes the 
 formation of blow-holes. 
 
 The metal should be cleaned in the im- 
 mediate vicinity of the weld and the edges 
 to be welded should be beveled. A welding 
 tip one size larger than is required for the 
 same thickness of cast-iron should be used. 
 On account of the high conductivity, it be- 
 comes necessary to pre-heat a consider- 
 able area in the vicinity of the weld to a 
 high temperature before starting to weld. 
 
114 OXY-ACETYLENE WELDING & CUTTING. 
 
 A neutral flame should be maintained and 
 the white cone should be held about 1 A of 
 an inch from the metal. A flux should be 
 used. While a pure copper rod is much 
 used, better results can be obtained with 
 a special rod containing a very slight per- 
 centage of phosphorus. 
 
 WELDING OP ALUMINUM. 
 
 Of late years, aluminum has come into 
 such common use that everyone is familiar 
 with it. When heated to a high tempera- 
 ture it becomes very fragile, not having 
 sufficient strength to hold up its own 
 weight. Like copper, its conductivity is 
 high. Its tendency to oxidize is greater 
 than that of any other commercial metal. 
 
 When the metal is heated to the melting 
 point, this oxide is easily seen and by the 
 workman is usually spoken of as the 
 ' ' skin." 
 
 The piece to be welded is prepared in 
 much the same manner as though it were 
 cast-iron or brass. The piece is cleaned 
 and the edges are beveled. For the begin- 
 ner we have one suggestion to make which 
 he will find of considerable assistance, but 
 which he may possibly discard after he 
 becomes proficient. We have already 
 stated that the metal has no strength when 
 it is around the melting point and the be- 
 
ALUMINUM WELDING. 115 
 
 ginner will very likely find his work sink- 
 ing in or holes dropping through it. 
 
 When this happens a few times the op- 
 erator is apt to become "rattled" and dis- 
 couraged. To avoid this happening one 
 can prepare the work as follows : 
 
 After the work has been cleaned and 
 beveled, wet some paper and lay over the 
 crack on the underside. Take a wire and 
 form a slight loop. Fasten one end to the 
 casting on one side of the crack and the 
 other end to a part of the casting on the 
 other side of the crack. Take some plaster 
 of Paris and add sufficient water until it 
 is of a thick consistency and then put it 
 on top of the wet paper and around that 
 part of the casting where the crack is lo- 
 cated. The wire mentioned above will act 
 as an anchor to hold the plaster of Paris 
 and prevent its falling out. The plaster 
 miist then be allowed to dry. When it 
 has done so, a perfect supporting mould 
 will have been formed. The wet paper has 
 prevented any of the plaster from getting 
 into the crack. We can now proceed to 
 weld without the danger of the casting 
 dropping in the event it should happen to 
 get a little too hot. 
 
 The average beginner is apt to consider 
 aluminum welding as very difficult. This 
 is not the case when one understands the 
 
116 OXY- ACETYLENE, WELDING & CUTTING. 
 
 nature of the metal and also keeps in mind 
 the principles of expansion and contrac- 
 tion. 
 
 Compared with cast-iron, what do we 
 find? That it melts at a very much lower 
 point and yet conducts heat very much 
 more. When heated, its expansion is great- 
 er and, of course, when cooling its contrac- 
 tion is greater than cast-iron. This means 
 that the portion that is brought to a molten 
 state by the flame will, when cool, occupy 
 less space than will cast-iron under the 
 same operation. The oxide or "skin" 
 already mentioned requires about twice as 
 much heat to melt it as does the metal. A 
 little reflection and we see that some ex- 
 ternal means must be resorted to in order 
 to destroy or remove this oxide before a 
 successful weld can be obtained. 
 
 There are three methods of doing this. 
 Each is good when properly executed. They 
 are: 
 
 First, welding by puddling. 
 
 Second, welding with a flux. 
 
 Third, combining these two methods by 
 puddling while at the same time using a 
 flux. 
 
 The puddling method was the first in 
 vogue and is still used quite extensively. 
 It consists in removing the oxide mechani- 
 cally by means of a rod, called a spoon. 
 
ALUMINUM WELDING. 117 
 
 Two spoons are employed and they are 
 very simple, consisting of two 3 /4" steel 
 rods, each flattened at one end and one of 
 them being bent at a right angle. The 
 right angle spoon is used to scrape out 
 the weld, while the straight spoon is for 
 working into shape the new material that 
 has been added into the weld. 
 
 In practice an operator starts heating 
 the metal and when he thinks it is about 
 the melting point he tries it with the right 
 angle spoon. If it is, the skin or oxide and 
 any dirt that may be present is carefully 
 scraped out for a distance of an inch or 
 two. The spoon is then dropped and the 
 filler rod is quickly taken up and material 
 added. 
 
 The straight spoon is then substituted for 
 the filler and the metal is worked and 
 shaped. When this is finished another 
 inch or two is started and continued until 
 the entire crack is welded. 
 
 Welding aluminum by means of a flux is 
 a more recent method. The aluminum is 
 heated to the melting point, as is likewise 
 the filler rod, when the latter is dipped into 
 the flux and is then brought into contact 
 with the molten metal at the weld. When 
 the weld is cold, the flux should be washed 
 off with water and a brush. 
 
 Either of these methods is good. The 
 
118 OXY-ACETYLENE WELDING & CUTTING. 
 
 first has the advantage of looks, while the 
 latter that of speed; the strength of each 
 is about the same. The third method is 
 rather fancied by the writer for repair 
 work. It is really a combining of the two 
 above-mentioned methods. 
 
 The spoon is used to clean out the weld. 
 The flux method is then used, and when a 
 few T inches of welding is done, we revert 
 back to the puddling method and use the 
 flat spoon for shaping and finishing up the 
 work. 
 
 WELDING MALLEABLE IRON. 
 
 Malleable iron is practically cast-iron 
 that has been annealed. If it is a thin cast- 
 ing this heat treatment tends to transform 
 the entire piece into a semi-steel, but if the 
 casting is fairly thick we may expect only 
 the outer portion to have been affected. 
 
 Beginners usually experience consider- 
 able difficulty in detecting a piece of malle- 
 able. Occasionally an experienced man will 
 be fooled. If the casting is not very thick 
 the color of the metal at the break will be 
 white in the center with a very narrow 
 dark ring around the outside. If the cast- 
 ing is fairly thick, the center portion will 
 appear cindery. When the torch is ap- 
 plied it is comparatively easy to recognize 
 it, When first heated it sparks a little, so 
 that vou know it is not cast-iron. When 
 
MALLEABLE IRON WELDING. 119 
 
 it commences to melt, blow-holes invari- 
 ably form. Some still cling to the notion 
 that it can be successfully welded with 
 steel or with cast-iron. This is not true. 
 Whenever steel or cast-iron is used on 
 malleable it shows a lack of knowledge of 
 the business. Whenever it becomes neces- 
 sary to melt malleable iron, upon cooling 
 it will be converted into a very poor grade 
 of cast-iron. 
 
 The only successful method of joining 
 two broken pieces of malleable is by braz- 
 ing. This has been proven to be entirely 
 satisfactory from a standpoint of strength, 
 if the work is properly carried out. The 
 Avork should be cleaned and beveled. Tobin 
 bronze or high-grade brazing wire is used 
 in conjunction with a flux. The malleable 
 iron should not be heated to the melting 
 point, a bright red or at the most a white 
 heat being employed. To start the braze, 
 the writer prefers the use of spelter, which 
 in this part of the country is the name for 
 fine particles of brass mixed with a flux. 
 This is sprinkled on the beveled edges and 
 coats the edges with a thin layer of brass. 
 We then take "the Tobin bronze rod and 
 finish by using it as filler, using it rapidly. 
 
 WELDING OF LEAD OR LEAD BURNING. 
 
 Lead burning, as it is commonly called, 
 
120 OXY-ACETYLENE WELDING & CUTTING. 
 
 is really the first form of autogenous weld- 
 ing. As the melting point is low, a tip 
 which gives an exceedingly small flame is 
 used. The edges to be welded should be 
 cleaned and scraped until bright. Since the 
 electric starter and electric lights are 
 almost universally used on automobiles, a 
 lead burning outfit is now almost a neces- 
 sity for the garage in the repair of bat- 
 teries. 
 
 While excellent work is done with oxy- 
 acetylene, ordinary coal gas and oxygen 
 is used with splendid results. In some 
 cases the coal gas is compressed into tanks, 
 but in the majority of cases a special de- 
 signed torch is used which permits of tak- 
 ing the coal gas direct from the city main 
 at a pressure of only a few ounces. Very 
 little skill is required for average work. 
 Ordinary clean lead cut into strips from 
 a sheet or just scraps is used as a filler. 
 
 For lead burning of chemical tanks or 
 containers it is sometimes necessary to do 
 vertical work. This .requires considerable 
 practice. It may be well to state, how- 
 ever, that a vertical weld is never so good 
 as a horizontal one and the natural infer- 
 ence is that whenever it is possible in work 
 of this character, the tank should be laid 
 on its side so that the work can be done in 
 a horizontal position. 
 
CHAPTER VII. 
 
 WELDING OF SHEET METAL AND PIPE. 
 
 WELDING OF SHEET IRON. 
 For the welding of very thin sheet iron, 
 say from No. 22 gauge to No. 28 gauge, 
 it is rather difficult to make a butt weld, 
 for the reason that almost as soon as the 
 metal is in a molten state, a hole has burned 
 
 Fig. 17. 
 
 This shows a butt weld, with edges beveled on one 
 side. For metal of l / s inch in thickness or less it is 
 not necessary or desirable to bevel. The dotted line in- 
 dicates the metal which has been added from the filler 
 rod. 
 
 through which is difficult to patch. It will 
 be found best to turn up the edges so that 
 a flange of as low a height as possible is 
 secured. Clamps should be used to hold 
 the metal even and the flange should be 
 
 Fig. 18. 
 
 This shows a butt weld on metal % inch in thickness 
 or more. In this case the bevel is from both sides. 
 This is desirable if both sides are accessible. 
 
 "spotted" or "tacked" at intervals of 
 
 about four or five inches. No filler rod is 
 
 used, as the flanges upon being melted down 
 
 121 
 
122 OXY-ACETYLENE WELDING & CUTTING. 
 
 supply the necessary material. Some knowl- 
 edge of sheet iron work is necessary in 
 order to properly make the flange. 
 
 For sheet iron of slightly greater thick- 
 ness, say Nos. 12, 14, 16, 18 and 20 gange, 
 the welds can be made in several ways. It 
 can be done by means of a flange as indi- 
 cated above for very light metal ; it can be 
 butt welded either with or without a filler 
 rod or it can be welded with a flange dif- 
 fering somewhat from that mentioned 
 above. 
 
 Fig. 19. 
 
 This illustrates two lap-welded joints, one in which the 
 weld is made only from one side and the other where 
 it was made from both sides. Ordinarily this is not a 
 desirable way to make a weld with the torch, but occa- 
 sion will sometimes demand it. 
 
 The above applies to the welding of ir- 
 regular shapes and small articles. If the 
 welding is on sheets formed as tanks or 
 containers, and the task is a quantity 
 proposition, more detailed information is 
 necessary. As previously stated, when 
 welding No. 20 gauge metal or higher it is 
 better to flange the edge. On this light 
 metal it is difficult to make the flange cor- 
 rectly; in fact, it cannot be done in a ma- 
 chine, owing to a tendency of the metal to 
 
SHEET METAL WELDING. 123 
 
 draw. The most satisfactory method is 
 to tightly fasten the sheet in a clamp, al- 
 lowing about 1/32 of an inch to extend be- 
 yond the clamps, and then turn the flanges 
 with a coarse file. This flange will be at 
 an angle of about 45 degrees, but as the 
 metal increases in thickness the flange will 
 be straighter until in No. 16 gauge and 
 heavier it will be almost at a right angle, 
 and it will be found to be easier to make. 
 
 =00= 
 
 Fig. 20. 
 
 This shows sheet metal flanged preparatory to welding 
 and also the appearance of the sheet after the weld 
 has been executed. It is to be noted that in the illustra- 
 tion the height of the flange is little more than the 
 thickness of the metal. When edges are prepared in 
 this manner, the molten metal of the flange flows onto 
 and incorporates with the metal of the sheet beyond 
 the knuckle of the flange. In some cases the flange 
 is made quite high from }4" to %" and of course just 
 the edges are melted together. 
 
 For flanging No. 20 gauge and heavier 
 an old press, working on the same 
 principle as a square shear, can be 
 utilized. It will have one sharp and one 
 dull die ; the dull one being on top and the 
 sharp one on the bottom. As the dull die 
 comes down it forms the edge or flange. 
 The top or dull die is 'set back, leaving a 
 gap, the width of which is equal to the thick- 
 ness of the metal. As an example, for No. 
 
124 OXY-ACETYLENE WELDING & CUTTING. 
 
 16 gauge metal, it would be set back 1/16 
 of an inch. Welds made with the metal 
 formed in this manner are to be preferred 
 to a butt weld even with a filler added, as 
 the weld is made faster, it is stronger as 
 considerably more metal of the same stock 
 is in the weld and in numerous tests made 
 with the same metal, operator, etc., where 
 all factors were the same, there were less 
 leakers. 
 
 Fig. 21. 
 
 This shows one method of welding in the heads or 
 bottoms of round tanks made from light stock. The 
 edge of the head is flanged and the two edges are fused 
 together. 
 
 Regardless as to whether the weld is a 
 flange or butt, it is advisable to have 
 clamps or what the trade calls stakes, for 
 holding the edges. 
 
 Usually an old railroad rail is utilized 
 for the mandrel portion of the stake. The 
 ball or top is machined so that the sheets 
 will be level. In the middle of the top a 
 longitudinal slot is cut about ^-ineh wide 
 and ^-inch deep. The edges of the sheet 
 are placed directly over this slot, its object 
 
.WELDING CLAMPS. 
 
 125 
 
 being to prevent the heavy rail from con- 
 ducting the heat away. Clamps are neces- 
 sary to hold the sheets in position on the 
 mandrel. They are made of two pieces 
 fastened together at each end and so ar- 
 ranged that the outer end can be lifted to 
 allow of the introduction and removal of 
 the sheets. The bottom of these clamps is 
 machined flat and the inner edge of each 
 clamp is beveled off so as to permit of the 
 introduction of the welding flame. The 
 clamps should be separated about one inch. 
 
 Fig. 22. 
 
 This is the same edge to edge welding and simply 
 shows how the ends of square tanks can be welded. 
 
 This depends somewhat on the thickness 
 of the metal being welded, widening the 
 clamps for the heavier metal and bringing 
 them closer together for the light stock. 
 For a butt weld, the edges should be put 
 into actual contact at the end where weld- 
 ing is started and they should be separated 
 at the other end. The distance of separa- 
 tion depends upon the length of the weld, 
 
126 OXY-ACETYLENE WELDING & CUTTING. 
 
 the thickness of the metal and the speed 
 of the operator. No hard and fast rule can 
 be given, but for a tank 34 inches long 
 made of No. 16 gauge metal it is usually 
 spread a /4 of an inch and for No. 18 gauge 
 metal the same length, it is spread about 
 3/16 of an inch. 
 
 
 Fig. 23. 
 
 This shows a dished and flanged head of a round 
 receptacle in position and partly velded. If the tank 
 is under only a slight pressure the weld can be made 
 at the knuckle of the flange. If the tank is for high 
 pressure the weld should be made farther down and 
 nearer the edge of the flange. 
 
 Some writers have fixed 2y 2 % of the 
 running length of the weld as the distance 
 the sheet should be spread, but this is often 
 erroneous. As the weld progresses, the 
 sheets come together. 
 
 WELDING OP CONNECTIONS. 
 
 In almost all containers, one or more con- 
 nections are necessary. A pipe nipple is 
 used, and for the sake of economy is usually 
 cut in two in the middle, thus making two. 
 It is then put in a lathe and a cut taken on 
 the inside threaded portion, leaving a 
 shoulder about % of an inch thick and 3/16 
 
MACHINE WELDING. 127 
 
 of an inch high. The hole in the tank is 
 flanged out and when in position for weld- 
 ing we have the edge of the sheet and the 
 thin edge or shoulder on the nipple adja- 
 cent. No filler is used. The two edges 
 are simply melted down and an entirely 
 satisfactory connection is made. (Fig. 27.) 
 
 
 Fig. 24. 
 
 This shows a dished head without a flange in position 
 and partly welded. This method is not recommended 
 where the container is subjected to high pressures. 
 
 MACHINE WELDING OF SHEET METAL. 
 
 Machine welding can be employed in the 
 manufacture of certain articles made from 
 rather thin sheet metal. Naturally, in 
 order to be practical, it, must be a repeat 
 or quantity proposition. These machines 
 are either automatic or semi-automatic. 
 For pipe of small diameter, wind shield 
 frames, etc., the metal is of thin gauge and 
 the operation consists of an autogenous 
 butt weld in combination with pressure. 
 This last is important. The two edges to 
 be w r elded are mechanically brought to- 
 gether so that they are even and in per- 
 fect alignment, and at the instant the oxy- 
 acetylene flame produces fusion of the 
 
128 OXY-ACETYLENE WELDING & CUTTING. 
 
 metal on top, rollers or shives engage both 
 sides of the tube, pressing or squeezing the 
 molten edges together. In practice the tube 
 or frame is formed and welded in one op- 
 eration. The work and not the torch moves. 
 Strips of sheet metal are cut as long as 
 desired, care being taken that the cut is 
 
 Fig. 25. 
 
 This shows two ways of welding 1 fittings or connec- 
 tions in tanks. 
 
 even and the width of the "sheet the same 
 throughout. It is then formed by being 
 drawn through dies, the position of the two 
 edges being on top so that they will come 
 under the flame. As the tube progresses 
 towards the torch it is guided by several 
 pairs of shives or rollers, one set of which 
 is located at a point where the flame touches 
 the metal. 
 
 The object of this particular set of shives 
 is twofold, first to guide the tube and sec- 
 ond to press in on the sides and squeeze 
 the metal together. Other sets of shives 
 may be arranged behind the flame to 
 straighten the tube should there be a ten- 
 
TANK WELDING. 129 
 
 dency towards distortion. At the present 
 time no real success has been obtained in 
 an effort to automatically butt weld thin 
 sheets when the diameter of the cylinder 
 was in excess of 12 inches. On the other 
 hand, the automatic welding of thin sheets 
 is entirely practical, regardless as to the 
 diameter, if the edges are flanged. This is 
 comparatively simple whether the vessel 
 is cylindrical or square. Sometimes the 
 flanges are tacked by hand at two or three 
 
 Fig. 26. 
 
 For divisions in tanks or where top or bottom is 
 required to be set in from end this illustrates a very 
 good way. The weld should be made on the flange near 
 the knuckle. 
 
 points before the actual welding begins. In 
 this case, the torch and not the work 
 travels. The torch is screw driven and 
 some experimenting is necessary in order 
 to determine the size tip necessary, the 
 angle it should take, and the speed it should 
 travel. For boxes and some cylinders no 
 clamping or supporting devices are neces- 
 
130 OXY-ACETYLENE WELDING & CUTTING. 
 
 sary. It is necessary to provide some 
 means for forcing together the two edges 
 of the flange immediately in front of the 
 flame. In some cases this is done by means 
 of a set of rollers that immediately precede 
 the flame, traveling automatically with 
 the torch; in others this is done by an op- 
 erator using a pair of pliers that is pro- 
 vided with a couple of small rollers. 
 
 Most automatic machines are limited as 
 to the scope of work which they will ac- 
 complish, but for the particular duty for 
 which they are designed they will do 
 beautiful, strong, rapid and cheap work. 
 
 Fig. 27. 
 
 In some instances it is advisable to use 
 a water-cooled tip, but for most work this 
 is not necessary. The necessity for a water- 
 cooled tip is greater where low pressure 
 acetylene is used, m view of the fact that a 
 considerable variance in the flame of a low 
 pressure torch is noted upon the tip be- 
 coming heated. On the other hand, where 
 high pressure acetylene is used, more at- 
 tention must be given to the regulators 
 to see that they are operating accurately. 
 
PIPE WELDING. 131 
 
 WELDING OF GAS, AMMONIA, AIR, STEAM AND 
 WATER PIPES AND MAINS. 
 
 During the past two years, the o^y-acety- 
 lene torch has been used quite extensively 
 for the welding of pipes and mains. 
 
 Fig. 28. 
 This shows special joint on gas main made by welding. 
 
 In the West, in some instances, hundreds 
 of miles of pipe have been laid without a 
 threaded connection, while in many cities 
 this class of welding has reached consider- 
 able proportions. It has been demon- 
 strated that the strength of the weld can 
 easily be made greater than that of an un- 
 welded pipe and the cost of the welded 
 connection is less than the cost of the 
 screwed connection. There is also no dan- 
 ger of leakage. Where pipe is welded a 
 much lighter wall is permissible, as no 
 allowance need be made in its thickness for 
 threading. This permits of a considerable 
 saving and at least one company is now 
 
132 OXY-ACETYLENE WELDING & CUTTING. 
 
 advertising a pipe having extra thin walls 
 for welding. By specifying, the mills will 
 furnish the pipe with the ends beveled at 
 no extra cost. In practice the work is 
 done as follows : 
 
 Fig. 29. 
 
 This shows special "Y" joint on gas mains made 
 by welding. 
 
 The pipe is laid end to end on top of 
 the ground. If the ground is uneven it 
 is best that they be supported by 2x4 's in 
 order that they can be easily turned. If 
 the pipes are cut at a bevel, the ends are 
 butted together. If, however, the pipes are 
 cut off straight a space of from 1/16 to 
 
WELDING GAS MAINS. 
 
 133 
 
 i/i-inch is allowed according to the size of 
 the pipe. In addition to the welder, two 
 helpers are furnished. They are stationed 
 one at each end of the section and their 
 
 Fig. 30. 
 
 This shows reducer made en gas main by welding; 
 flange is also welded on to pipe. 
 
 duty is to turn the pipe with tongs as the 
 welding progresses, always permitting the 
 operator to weld on top of the pipe, as 
 greater speed can be made. The pipe 
 
134 OXY-ACETYLENE WELDING & CUTTING. 
 
 should be turned towards the welder. Hose 
 of sufficient length should be provided so 
 
 This shows a spiral coil made of continuous lengths 
 of pipe, homogeneously welded and bent into shape. 
 These coils are used in refrigerating systems. 
 
 that he may weld from either side of the 
 pipe. Ordinarily, pipe comes in about 20- 
 
WELDING PIPE. 
 
 135 
 
 foot lengths, but for welding purposes it 
 can be procured in 40-foot lengths, thereby 
 reducing the connections. In cities, the 
 number of lengths that can be welded to- 
 
 Fig. 32. 
 
 This shows 37 feet of pipe, originally in two pieces 
 but welded together in the center and bent to form 
 an expansion loop. The weld can be seen just above 
 the crane hook. 
 
 gether is usually limited by the length of 
 the blocks, but in the country quite fre- 
 quently lengths of 1000 feet or more are 
 
136 OXY-ACETYLENE WELDING & CUTTING. 
 
 welded together before rolling into the 
 trench. 
 
 The welding of two sections in the trench 
 is more difficult. This weld must of neces- 
 sity be a stationary one, so a pit must be 
 dug of sufficient size to permit the operator 
 
 Fig. 33. 
 
 This shows a welded drip composed of 16-inch pipe. 
 This not only makes a better job but on this drip there 
 was a saving of $450.00 over the old method. 
 
 Courtesy of National Tube Company. 
 
 to work on both sides and under the pipe. 
 The welding at this connection consists of 
 !/4 horizontal, y 2 vertical and % overhead, 
 but with practice this is easily accom- 
 plished. It follows that all sorts of tees, 
 angles, reducers and connections can be 
 welded. 
 
STRENGTH OF WELDS. 137 
 
 It may be of interest to give the result 
 of some tests showing the relative strength 
 of welded and screwed pipe connections. 
 
 Pipe Size Dia. Welded Connection Screwed Connection 
 
 1/2 in. 12250 pounds 8560 pounds 
 
 % in. 21276 pounds 12640 pounds 
 
 1 in. 29810 pounds 17560 pounds 
 
 1V 2 in. 44120 pounds 31440 pounds 
 
 Fig. 34. 
 
 This gives some idea of the appearance of a cross in 
 an 8 inch main when welded. 
 
 The cost of welding depends upon the 
 skill of the welder, the efficiency of the 
 apparatus and also upon local conditions. 
 
138 OXY-ACETYLENE WELDING & CUTTING. 
 
 If not delayed too much in moving from 
 one point to another, a competent man will 
 weld as follows : 
 
 10 to 12 joints of 
 
 5 to 6 joints of 
 
 3 to 4 joints of 
 
 2 to 3 joints of 
 
 1 joint of 
 
 2 inch pipe per hour 
 
 3 inch pipe per hour 
 
 4 inch pipe per hour 
 6 inch pipe per hour 
 
 8 inch pipe in about 40 min. 
 
 1 joint of 12 inch pipe in about 1 hour. 
 
 Fig. 35. 
 
 This shows a 3 inch lateral welded to an 8 inch main; 
 a simple operation for the Oxy-acetylene torch. 
 
 A comparison of the cost of joints of 
 different size welded and with threaded 
 couplings follows: 
 
 Size of Pipe 1/2" %" 1" iy 2 " 2" 3" 4" 
 
 Butt Welded Joints. $0.03 .04 .05 .07 .10 .18 .30 
 Threaded Couplings $ .04 .05 .07 .11 .15 .32 .52 
 
COST OF WELDING. 139 
 
 Attention is directed to the fact that as 
 the pipe sizes increase, the advantage of a 
 lower cost for the welded joint is very 
 much greater. 
 
 It follows that the welding of steam, air 
 and water pipes in industrial plants, rail- 
 road shops, yards, etc., is entirely feasible 
 and in a great many instances preferable 
 to threaded connections. As an example, 
 the Terminal Kailroad Association of St. 
 Louis have welded all of the pipes running 
 through their yards. The St. Louis Re- 
 frigerating & Cold Storage Company 
 welded a great many miles of their street 
 ammonia, pipes and the results are so 
 satisfactory that they are replacing the 
 screwed connections with welded joints as 
 rapidly as possible. 
 
CHAPTER VIII. 
 
 WELDING or VARIOUS PIECES. 
 
 WELDING OF BOILERS. 
 
 Probably in no field of welding has ad- 
 vancement been faster or the application 
 greater than in the repair of boilers. 
 Cracks, patches and entire sheets are now 
 welded with complete success. Naturally, 
 there are various ways of doing this weld- 
 ing, and it follows that practical men will 
 frequently conscientiously differ as to 
 which method is the best. It is the desire 
 of the author to give to you at least one 
 way of doing the work well. If you can 
 improve over it, so much the better. 
 
 The first job we will discuss is the weld- 
 ing of a half side sheet in a locomotive fire 
 box. With the exception of the side which 
 is to be welded the new sheet is prepared 
 exactly as though it were to be riveted in. 
 When possible, all stay bolts should be put 
 in, with the exception of a row on each 
 side of the weld. The mud ring and the 
 door and flue sheets can be riveted in, 
 leaving two or three rivets on each side 
 of the weld so that the flange can be raised 
 up to allow the sheet to be welded un- 
 derneath. 
 
 If the front and flue sheets are old ones 
 
 140 
 
BOILER WELDING. 141 
 
 this can be omitted and tjie flange welded 
 to the side sheet for six or more inches 
 each way. The rivets should be put in 
 after welding. While it is usually more 
 convenient to put in at one time all of 
 the stay bolts and rivets, with the excep- 
 tions noted above, it is not necessary, and 
 it can be dispensed with, excepting one 
 row of stay bolts which hold the edges to- 
 gether. No bad effects will follow, the 
 sheet will not draw up a bit and the rivet 
 holes in the. mud ring and the stay bolt 
 holes will line up perfectly. Of course, the 
 edges of the new and the old sheet where 
 the weld is to be made are beveled so that 
 they form an angle of 90 degrees/ A space 
 or opening about *4" wide is allowed be- 
 tween the two sheets. The new sheet is 
 cut to allow for this, if not a ripping tool 
 is used to provide it. When the sheet is 
 properly fitted the welding is begun. It 
 will now be necessary to refer to Fig. 36, 
 which represents a side sheet ready for 
 welding. The edge next to and under the 
 flange No. 1 is first welded. We then move 
 ahead about ten inches to No. 2 and weld 
 back to No. 1, then go to No. 3 and weld 
 back to No. 2 and so on across the sheet. 
 It is sometimes necessary to have a pinch 
 bar to pull the edges in line; otherwise, 
 there will be no trouble with the welding. 
 
142 OXY-ACETYLENE WELDING & CUTTING. 
 
 Dozens of sheets have been welded in 
 this way without any trouble, except in 
 the case of a green man who was not able 
 to make a weld. One advantage is, the 
 welder can stop at any time without any 
 trouble. 
 
 O Oja 
 
 o cyr 
 
 Fig. 36. 
 
 There are two other methods used in 
 welding in side sheets, which the writer 
 does not like so well, but which are used 
 by others with from fair to good results. 
 
 The first consists in dropping one end 
 of the sheet about 2% of the running 
 length. This was perhaps the first method 
 used in this country and some still cling to 
 it. If the sheet is dropped the correct dis- 
 tance, it will pull up into place as the weld- 
 
BOILEB WELDING. > 
 
 ing progresses. The trouble, however, is 
 due to the fact that there can be no fixed 
 rule for determining how much the sheet 
 should be dropped for each individual weld- 
 er. The reason is that this distance which 
 the sheet is dropped is determined to a 
 very considerable extent by the speed of 
 the wilder, and no two men weld at the 
 same speed. 
 
 The other method consists in putting in 
 the new sheet as though it were to be riv- 
 eted. The stay bolts are put in except the 
 two or three rows at the top near the line 
 of the weld. Bolts are put through the 
 outer sheet and forced against the new 
 sheet. This shoves the new sheet away 
 from the line of the weld. Another bolt 
 is nearer the edge to be welded and it 
 extends to the outer sheet. An assistant 
 on the outside tightens this bolt and pulls 
 the new sheet back into position. By do- 
 ing this a corrugation or hump is produced 
 in the new sheet just below the line of the 
 weld. The welding can progress from 
 either end, and as it does the bolts should 
 be released, with the result that the con-<$> 
 traction pulls the corrugation out, leaving 
 the sheet straight and in good shape. 
 
 WELDING OP A SIMPLE CRACK. 
 
 The crack is prepared by being beveled 
 
144 OXY-ACETYLENE WELDING & CUTTING. 
 
 to the usual 90 degree angle. A y 8 -incli 
 to i/i-inch opening is made at the bottom, 
 depending upon the length of the crack. 
 Before welding, heat in the line of the weld 
 for several inches at the ends of the crack. 
 This is done to expand the solid sheet and 
 open the crack. If the crack is a short one 
 of only a few inches, start at one end and 
 finish up at the other and then lieat a 
 few inches beyond. 
 
 If the crack is a long one, say 18 inches 
 or more, instead of starting at the end, 
 begin about 8 inches from the end, and 
 weld back in exactly the same manner as 
 indicated for welding in a side sheet. 
 
 WELDING OP A PATCH. 
 
 In the welding of patches, it is preferable 
 to use a triangular patch, with the corners 
 slightly rounding, say about one inch 
 radius. With this shape of patch there 
 can be no parallel welds as is necessary 
 with any other shape, and this is to be de- 
 sired; also there are only three sides or 
 legs to weld. Each leg of the patch should 
 be straight. The bad place is cut out with 
 the cutting torch and the patch fitted in, 
 first being prepared by beveling, etc., the 
 same as was done in the case of the side 
 sheet and the crack. 
 
 By referring to Figs. 37 and 38, the man- 
 
BOILER WELDING. 
 
 145 
 
 nor in which the weld is made will be easier 
 understood. 
 
 In Fig. ,37, we show a patch in the form 
 of a right angle triangle and in Fig. 38 the 
 patch is an equilateral triangle. The weld- 
 ing differs little in either. The welding 
 is started at No. 2 and the weld is made 
 towards No. 1, then we go to No. 3 and 
 weld to No. 2 and from No. 4 to No. 3. 
 
 Fig. 37. 
 
 It is then preferable to allow the weld to 
 cool down, and then before starting weld- 
 ing heat in the line of the weld No. 4 to 
 No. 7 for about 6 inches at each end, as 
 shown by XX. Then start welding at No. 
 5 and weld to No. 4, jump to No. 6 and 
 weld to No. 5 and finish this leg with a weld 
 from No. 7 to No. 6. Then let this weld 
 
146 OXY-ACETYLENE WELDING & CUTTING. 
 
 cool and before starting on the final leg 
 heat in the line of the weld No. 7 to No. 1 
 for about 6 inches as shown by XXX. In 
 making this final weld it is better, if pos- 
 sible, to start at No. 10 and weld to No. 1, 
 then at No. 9 and weld to No. 10 and so on 
 until completed. By doing this the weld is 
 made upwards, which is faster and easier. 
 Of course, conditions are sometimes such 
 that this is not desirable. It is simply a 
 matter of convenience. 
 
 Fig. 38. 
 
 There are some who use a dished patch 
 and others one with the edges corrugated. 
 Undoubtedly patches made in this manner 
 are at times of assistance to the welder, but 
 the writer is strongly of the opinion that 
 this is not necessary if the welding is done 
 
BOILER WELDING. 147 
 
 properly. An examination of a n umber of 
 welds that proved defective, showed con- 
 clusively in nearly every instance that 
 either the welding or the judgment was 
 poor, or both. Any boiler sheet should 
 stand the shrinkage of one welded seam 
 and if that weld is allowed to cool before 
 the next weld is made there will only be 
 the shrinkage of one weld to consider when 
 the last weld is made. There should be 
 very little strain in a weld when cold. 
 AYhenever a weld cracks immediately after 
 welding while it is still hot, an indication 
 that the weld is poorly made, it will be 
 found that the crack opens widely, some- 
 times as much as % of an inch. 
 
 If the weld is properly made and it 
 should crack, which will only happen after 
 it becomes cold, it will be found to show as 
 a very faint line. This shows that in cool- 
 ing the metal in the good weld stretched 
 considerably, whereas in the poor weld 
 there was not sufficient strength to permit 
 of the metal stretching. 
 
 WELDING CRACKS IN THE THROAT 
 SHEET OF BOILER. 
 
 Cracks often form at the throat sheet. 
 They usually begin at the water side. A 
 great many consider it impossible to suc- 
 cessfully weld cracks of this kind, and yet 
 
148 OXY-ACETYLENE WELDING & CUTTING. 
 
 the writer knows thoroughly competent op- 
 erators who are doing this with entire satis- 
 faction. The work must be carefully done 
 and the weld reinforced for about one inch 
 on both sides of the line of the weld and be- 
 yond the end of the crack, and when fin- 
 ished, heated in the same line for some dis- 
 tance each end of the weld. Where pos- 
 sible the weld should be made on both the 
 water side and the outside, but one side 
 alone will do. 
 
 WELDING OF AUTOMOBILE CYLINDER. 
 
 The welding of an ordinary crack in the 
 water jacket of an automobile cylinder is 
 not a difficult task if one has a fair knowl- 
 edge of welding and carries out to the let- 
 ter instructions as to pre-heatirig. The 
 cylinder should always be stripped, and if 
 possible educate your customers to bring- 
 ing them to the shop in this condition. 
 Valves, springs, pet-cocks, etc., -should all 
 be removed. The cylinder should be care- 
 fully examined in a good light to determine 
 if possible whether there are airy cracks 
 other than those which are easily seen. 
 Sometimes, when considerable care is exer- 
 cised, but frequently through carelessness, 
 the operator overlooks a crack and has to 
 reweld the cylinder. The cracks should be 
 chipped to a 45-degree angle with a diamond 
 
CYLINDER WELDING. 149 
 
 point. This not only insures a better weld, 
 but when this is done one is very much more 
 apt to detect stray cracks If the cylinder is 
 painted, this should be removed for about 
 an inch on both sides of the weld by means 
 of an old file. Some graphite should be 
 obtained and mixed with kerosene until it 
 is of a thick, pasty consistency. This 
 should be rubbed on the inside of the 
 cylinders and on the valve seats and also 
 on the threads of the valve chambers by 
 means of a swab, which is simply made by 
 tying some rags or waste on the end of 
 an iron rod. This may seem unnecessary 
 to some, but it certainly will protect those 
 parts which are covered with it, and their 
 appearance after the welding is finished 
 will be better. This will please the custom- 
 er, and the writer believes you cannot be 
 far wrong when you do that. 
 
 Tike cylinder is now ready for pre-heat- 
 ing. Place it with the valve parts down 
 and the open end of the cylinder up. Do 
 not lay it on its side. Usually there is an 
 abundance of old scrap asbestos around a 
 welding shop, and some think it advisable 
 to fill the cylinder with this. Certainly it 
 can do no harm, and it may do good. En- 
 close the cylinder on all sides with fire 
 brick; this makes a temporary furnace. If 
 charcoal is used it should be lighted and 
 
150 OXY-ACETYLENE WELDING & CUTTING. 
 
 allowed to burn of itself. No forced draft 
 should ever be employed. Remember that 
 what is desired is an even heat, and this is 
 best obtained by slow heating. If coal gas 
 is employed, a torch using atmospheric air 
 should be used, and the flame made to 
 impinge on the brick not on the cylinder. 
 A piece of sheet iron or asbestos paper is 
 laid on top of the brick furnace to keep out 
 any drafts. Some use a metal hood, count- 
 er-weighted, which will cover the entire 
 furnace. Occasionally the cylinder should 
 be examined as to its condition. The de- 
 gree to which it should be heated is one 
 of the things on which there is a difference 
 of opinion. 
 
 Some heat to a point where it is just 
 too hot to lay your hand on, others heat 
 to a dull red, while there are some who 
 raise the temperature still higher. The 
 writer's experience would justify hi^ ad- 
 vising almost a dull red heat. The cylmder 
 should then be turned in a position for 
 welding. If charcoal is used it is left in the 
 fire; if coal gas the torch is either turned 
 low or extinguished altogether. For turn- 
 ing or moving the cylinder, d small chain 
 block with an old pair of ice tongs will 
 be found very convenient, eliminating in 
 many instances the need of a helper. The 
 welding should then be done. If it is a 
 
WELDING OF A LUG. 151 
 
 long crack or several, requiring consider- 
 able time, it is best to stop before com- 
 pletion and reheat by the addition of more 
 charcoal or by turning on the gas torches. 
 When finished, again turn on the gas 
 torches for a while or replenish the char- 
 coal, cover well and let it cool slowly. 
 
 In justice to yourself and your customer, 
 always test the cylinder under water pres- 
 sure before sending it out. For doing this 
 quickly a number of wooden plugs of differ- 
 ent sizes should always be kept on hand for 
 closing openings for which you will prob- 
 ably have no plugs. If you have a water 
 system, connect the water line with one 
 opening and turn on the pressure. If ,not, 
 fill with water and use a hand pump, rais- 
 ing the pressure to 15 or 20 pounds. 
 
 WELDING OP A LUG ON A MANIFOLD 
 OR A CYLINDER 
 
 Anyone familiar with either casting will 
 know that their faces are machined and, 
 therefore, true. Naturally, it is desirable 
 that this alignment be maintained when 
 welding on a lug that has been broken off. 
 
 If one possesses a face plate or a straight 
 edge, the manifold or the cylinder can be 
 clamped to it, first plncinir underneath two 
 or three thicknesses of ordinary paper. 
 Place the roken lug in position and either 
 
152 OXY-ACETYLENE WELDING & CUTTING. 
 
 clamp it down or hold in place with a two 
 or three-pound weight. Do not use any 
 paper under th. broke;* lug. B\ doing this, 
 the lug will be slightly lower than the re- 
 mainder of the casting and this will allow 
 for the pull or shrinkage in the metal. Tack 
 the weld at one side and then start at the 
 other side and weld around to where the 
 ' ' tack" was made. The clamps should then 
 be removed and the casting turned over 
 and the weld touched up from this side. 
 After the weld is finished, cover with as- 
 bestos and allow to cool. If there should 
 be a slight excess of metal on the machined 
 side it can easily be filed off. 
 
 REPAIRING A SCORED CYLINDER. 
 
 Frequently a wrist pin works loose, with 
 the result that the friction wears a slot 
 almost the entire length of the cylinder. 
 This means loss of compression, and if the 
 score is very deep, very little power will 
 be obtained from that cylinder. To repair 
 this by welding is not an easy undertak- 
 ing. When the welding is completed, of 
 course it is necessary to regrind the cyl- 
 inder. This is not objectionable, but in 
 the majority of cases it is necessary to 
 regrind until the cylinder is enlarged, 
 which moans an oversize piston must bo 
 used. In addition to this added expense 
 
WELDING CRANK CASE ARM 153 
 
 there are other objections, so that we would 
 advise brazing. The cylinder must be pre- 
 heated just as though welding were to be 
 employed. Particular care should be used 
 in cleaning the score. Tobin or manganese 
 bronze can be employed, using a flux. 
 Those shops not equipped to do regrinding 
 will find this method of repairing an ad- 
 vantage. A small portable grinder is used 
 to remove the roughness, and it can then 
 be finished with scrapers. 
 
 WELDING ARM OP AN ALUMINUM CRANK CASE. 
 
 Fig. 30. 
 
 Quite frequently the arm of a case 
 breaks. This is comparatively a simple 
 weld. There is no necessity to take care 
 of expansion and contraction. It is neces- 
 sary to take care of alignment, and to this 
 end a straight bar should be bolted tight to 
 
 the other arm on 
 
 same 
 
 sid( 
 
 the 
 
 case, the broken arm resting on the bar and 
 
154 OXY-ACETYLENE WELDING & CUTTING. 
 
 being clamped to it, care being taken that 
 the clamps are not drawn too tight. It will 
 be best to start welding along the top first 
 and then weld each side, finishing by weld- 
 ing on the inside, where a fillet or rein- 
 forcement can be made. 
 
 WELDING CRACK IN ALUMINUM OIL PAN. 
 
 Fig. 40. 
 
 Fig. 40 shows an aluminum oil pan with 
 a crack, AB, lined up and ready to weld. 
 Angle irons are bolted to the case. The 
 holes in the angle irons should be some- 
 what larger than the holes in the case and 
 the bolts should not be drawn tight so 
 that the case will have an opportunity to 
 expand when heated, but will do so along 
 the line and in the direction of the angle 
 irons. The case should be pre-heated, either 
 with charcoal, gas torch or with the weld- 
 ing torch. The heating should mainly bo 
 on the side opposite to the crack AB. The 
 
WELDING A FLY-WHEEL. 155 
 
 degree of heat is not only somewhat diffi- 
 cult to determine, but is also one regarding 
 which good welders differ. Some prefer 
 to heat until the metal begins to sweat. In 
 the majority of instances this is not neces- 
 sary, besides one is getting dangerously 
 near the point where the case will collapse 
 and be ruined. Others take some salt or 
 sawdust and sprinkle on the case, and if it 
 chars or burns quickly, proceed to weld. 
 The welding should start at A and proceed 
 towards B ; never in the opposite direction. 
 Always work a weld out towards the edge. 
 AVhen the weld is practically completed, 
 the one angle iron on that side should be 
 removed and the crack touched up, a little 
 more metal being added than necessary. 
 This excess metal can easily be filed off. 
 
 WELDING OF A FLY-WHEEL. 
 
 X 
 
 41. 
 
 Fii>'. 41 represents a cast-iron fly-wheel, 
 having a break in a spoke at A, and also 
 
156 OXY-ACETYLENE WELDING & CUTTING. 
 
 a break in the rim at B. First, let us as- 
 sume that there is only one break, and it 
 is at "A." We should have learned by 
 this time that if we attempted to make this 
 weld and gave no thought as to expansion 
 and contraction, that it would be sure to 
 break again when cooling. The proper way 
 to take care of expansion and contraction 
 is to heat the rim to a dull red on both sides 
 of this broken spoke. As the rim is heated 
 it expands outwardly, and it will be seen 
 that the edges of the break have separated. 
 The weld should then be made as rapidly 
 as possible and the wheel covered up care- 
 fully and allowed to cool slowly. 
 
 Now let us suppose that we have a bro- 
 ken spoke, A, and a broken rim, B. This 
 is really more simple than the one single 
 break in the spoke at A, if we go at it in 
 the proper way. The break at A must 
 always be made first. Before beginning 
 the weld, two flat iron bars should be 
 clamped along the sides of the rim to main"- 
 tain alignment. The weld at A should be 
 started and a heavy "tack" made, then 
 turn the wheel over and weld one-half the 
 way through, when the wheel should again 
 be turned, the "tack" melted out and the 
 weld completed. Upon examining the 
 crack in the rim at B, in nil probability it 
 will be seen that the part of the rim, XB, 
 
WELDING CRANK SHAFT. 157 
 
 extends a little farther out than does BY. 
 This, of course, is due to the fact that 
 the spoke has expanded from the heat of 
 welding, so we should carefully heat the 
 rim at Y until it expands and the two edges 
 of the crack at B are even and true. Then 
 make the weld, cover the casting and cool 
 slowly. 
 
 WELDING OP LARGE CYLINDERS. 
 
 In the pre-heating of large cylinders usu- 
 ally better results can be obtained by chang- 
 ing somewhat the method used on ordinary 
 automobile cylinders. The inner wall of 
 large stationary gas engine cylinders is 
 usually considerably heavier than the out- 
 er or water jacket wall. The cylinder 
 should be well swabbed with graphite and 
 then stood upright, the lower end resting 
 on bricks, leaving an air space of about 3 
 or 4 inches at the bottom. Some charcoal 
 is then placed inside the cylinder and al- 
 lowed to heat until the outer wall is fairly 
 hot. It then should be turned over on its 
 side and heated all over. 
 
 If gas torches are used, this is not neces- 
 sary, as a small one can be placed so as 
 to play on the inside, but not against the 
 walls of the cylinder. 
 
 WELDING A CRANK SHAFT. 
 
 The welding of a crank shaft should not 
 
158 OXY-ACETYLENE WELDING & CUTTING. 
 
 be attempted until one has had at least a 
 year's experience in welding. Automobile 
 shafts are steel with a fairly high carbon 
 content, and, in addition, frequently con- 
 tain nickel, chrome, etc. Good welders can 
 do this class of work successfully ; the fair 
 or mediocre operator would do well to 
 "pass them up." 
 
 Fig. 42. 
 
 Regardless as to the quality of the weld, 
 it will be necessary to put the shaft in a 
 lathe and do some straightening, after the 
 weld is completed. 
 
 Now the amount of work required in 
 
WELDING TANK WAGONS. 159 
 
 straightening can be considerable or very 
 little, depending upon the care exercised 
 in lining np the shaft before welding, and 
 the means for holding it approximately in 
 that position. Some advocate the use of 
 "V" blocks for this purpose. Besides be- 
 ing quite expensive, they are of very little 
 value, and a straight piece of heavy angle 
 iron will answer as well. 
 
 A simple and inexpensive means for 
 holding shafts is shown in Fig. 42. It is 
 copied very much after the steady rest on 
 a lathe. The shaft is lined up by means of 
 set screws arid a straight edge and a sur- 
 face gauge are used to determine when it 
 is correct. The shaft is then tacked and 
 again tried to see if it is true and the set 
 screws are tightened so that the shaft can 
 be easily turned. The weld is then made. 
 
 AVhen finished and while hot, it is again 
 tested, and if "off" it is an easy matter 
 to straighten by tightening up on one set 
 screw while loosening the opposite one. 
 
 A great many shafts have been welded 
 on a device of this kind and very little ma- 
 chining was necessary afterwards. 
 
 WELDING OF PARTITIONS IN OIL TANK 
 WAGONS. 
 
 Most of the oil concerns who deliver 
 oil in tank wagons, when ordering new 
 
160 OXY-ACETYLENE WELDING & CUTTING. 
 
 tanks are specifying that they shall be 
 welded throughout. These tanks carry 
 gasoline, kerosene and other grades of oil, 
 so that this calls for several compartments, 
 necessitating partitions. As a leak in a 
 partition might result seriously, they usu- 
 ally specify that there must be provided 
 two partitions, instead of one. These par- 
 titions are made from flat stock and are 
 
 V 
 
 dished very much like a pie pan. This is 
 practically all that is necessary, to take 
 care of expansion and contraction. The 
 edges at the ends of two tanks are flanged, 
 the two dished partitions are set in posi- 
 tion (see Fig. 43), and the four edges are 
 tacked at four or five points. The four 
 are'then welded all the way around. 
 
CONSTRUCTION OF WELDING HORSE. 161 
 WELDING HORSE. 
 
 Figure 44 shows a welding horse, with 
 aluminum case in position being welded. 
 This horse is so simple to make and yet is 
 so great a convenience in a custom repair 
 shop, that a description of it and its uses 
 would seem advisable. 
 
 In the majority of shops the custom has 
 been for the welder to use a helper when 
 working on aluminum cases, especially if 
 they were of rather large size. The du- 
 ties of the helper were to turn the casting 
 from time to time, keeping the portion that 
 was actually being welded in a horizontal 
 position. Sometimes the helper was dis- 
 pensed with and the welder did his own 
 turning, supporting the casting, from time 
 to time, by means of brick or other de- 
 vices. At times this places a considerable 
 strain on the casting, causing it in some 
 instances to crack elsewhere than in the 
 weld. Often the supporting bricks, hav- 
 ing been placed hurriedly in position, 
 would slip and allow the case to drop, with 
 more or less resulting damage. This weld- 
 ing horse eliminates all of this. The case 
 is simply bolted to the frame of the horse. 
 The frame and the attached case can re- 
 volve on the supporting shaft by loosening 
 a set screw and can be instantly fixed in 
 
162 OXY-ACETYLENE WELDING & CUTTING. 
 
 any desired position by simply tightening 
 the set screw. This horse is made as fol- 
 lows : 
 
 The legs are made of ordinary standard 
 %" PiP e an d are Cl1 ^ about 32 inches long. 
 A piece of l^i-inch pipe about six inches 
 
 Fig. 44. 
 Welding 1 Horse for Holding Aluminum Cases. 
 
 long is butted against two legs and welded. 
 The legs should be positioned to incline in- 
 ward somewhat. On the top of the short 
 l^-inch pipe build up a lug about %-inch 
 high. Then drill about a %-inch or %-inch 
 
DIE WELDING. 163 
 
 hole and tap. This is to receive a set 
 screw. Then get tw^o straight pieces of 
 angle iron about 4 or 5 feet long. This 
 angle iron should be about 2"x2"x 1 / 4". At 
 each end cut out a small square from one 
 flange about 2"x2". 
 
 This cut should be made on the same 
 flange for both pieces of angle iron. Weld 
 on the under side of the uncut portion a 
 piece of bar stock formed in a "U ?? shape. 
 This will form a slot through which 
 passes a flat bar forming the end. On the 
 side of the "U" shaped piece build up a 
 lug, drill and tap for a set screw 7 . 
 
 For the ends, get two pieces of flat stock 
 about li/X/'x 1 /^"? and each two feet long. 
 In the center of each and at right angle 
 weld a piece of 1" pipe about 8" long. These 
 two pieces of pipe will form the shaft for 
 the welding horse and the bearings will be 
 the two pieces of l 1 /^" pipe welded onto the 
 legs. The two pieces of angle iron which 
 form the sides can be moved in or out on 
 the two flat bars forming the ends, and 
 thereby adjusted to the width of the case. 
 Ordinary clamps are used to fasten the 
 case to the angle irons. 
 
 WELDING OP DIES. 
 
 Dies are, of course, made from high car- 
 bon steel. As we have previously stated, 
 
1 ()4 OX Y- ACETYLENE WELDING & CUTTING. 
 
 high carbon steels are difficult to weld; 
 however, very satisfactory welding is done 
 on this class of work. Ordinary Norway 
 iron can be used as a filler, but it must be 
 remembered that it will be impossible to 
 temper the metal in the weld on account 
 of its low carbon content. Some concerns, 
 notably shoe factories, use a great many 
 small cutting dies. They are very thin, 
 and the breakage is considerable. In weld- 
 ing, Norway was used, but it was exceed- 
 ingly difficult to prevent blow-holes from 
 forming near and at the thin cutting edge. 
 By experimenting, a high carbon filler rod 
 was found which eliminated this trouble 
 and also gave a harder cutting edge. Those 
 interested sufficiently to write to the author 
 .will be gladly given the name of this steel. 
 
 WELDING OF HIGH CARBON TOOL STEEL 
 TO LOW CARBON. 
 
 The exceedingly high price of high car- 
 bon steel during the past year has caused 
 many concerns to interest themselves in 
 some method that would show an economy 
 in the use of this material, with the result 
 that a great many are now using for their 
 cutting tools a small piece of high carbon 
 to which has been welded a longer piece of 
 low carbon. The same thing is done with 
 high speed and tool steel. Very little, if 
 
TOOL STEEL WELDING. 165 
 
 any, bevel is made on the high carbon piece, 
 whereas a very long bevel is made on the 
 low carbon bar. The secret as to success- 
 ful welding on this class of work is in pre- 
 heating both pieces until they are a cherry 
 red all over and then welding fast, using 
 as a filler either vanadium or nickel steel, 
 although Norway can be used. 
 
 WELDING OF MANGANESE STEEL. 
 
 The welding of manganese steel is not 
 a success. While the metal can be run to- 
 gether, the weld will be found to be porous, 
 brittle, and, of course, possessing little 
 strength. It is extremely doubtful if it 
 ever will be welded successfully with the 
 flame. The government specifications for 
 this steel call for a manganese content of 
 not less than 11% nor more than 13%. 
 Manganese has a great affinity for oxygen, 
 with the result that when the steel is melted 
 a considerable amount of the manganese 
 burns out, leaving less than 11% behind. 
 Attempts to put manganese back into the 
 casting by using a filler rod high in man- 
 ganese have not proven a success, as it 
 would be luck if only enough were added to 
 come within the narrow range of from 11% 
 to 13%. Manganese steel is used for switch 
 frogs, safes, ore crushing rolls, dredge dip- 
 pers, etc. 
 
\ - 
 
 166 OXY-ACETYLENE WELDING & CUTTING. 
 THE USE OF ALUMINUM SOLDER. 
 
 Those doing custom welding should be 
 capable of soldering aluminum. It is not 
 difficult, and there are occasions when its 
 use is desirable. It must be remembered 
 that a soldered joint will not have the 
 strength of a weld, claims of some manu- 
 facturers of aluminum solder to the con- 
 trary notwithstanding. For that reason 
 soldering should not be resorted to where 
 it is necessary to secure in the joint 
 strength equal to other parts of the cast- 
 ing. A small crack in the bottom of an 
 aluminum oil pan is an instance in which 
 soldering can be successfully done. Here 
 there is no strain and little strength re- 
 quired. The important consideration is 
 that it shall be oil tight. 
 
 The crack is beveled out to an angle of 
 at least 90 degrees. It is of the utmost 
 importance that it shall be clean and 
 bright. A tip of small size should be used 
 in the welding torch and only the brush 
 flame or envelope brought in contact with 
 the metal. While the crack is being heated 
 a wire hand brush should be used vigor- 
 ously until the sides are as bright as a 
 new silver dollar. Any good aluminum 
 solder can be used. There are quite a 
 number on the market. As soon as the 
 crack is clean and fairly warm, rub the 
 
SOLDERING ALUMINUM. 167 
 
 end of the solder in the crack and on the 
 side and a small amount will adhere. The 
 wire brush must be then used again, rub- 
 bing the solder in until every crack, crevice 
 and part of the beveled sides are coated 
 with the solder. While this is being done 
 the torch is being played over the crack and 
 by this time the casting should be hot 
 enough to melt the solder when it is rubbed 
 against the crack. Melt enough to fill up 
 the crack and extend over the sides a little 
 and use an old hickory hammer handle that 
 has been flattened on one side to press the 
 solder into shape. When this has been 
 done, be careful not to move the casting 
 until it has cooled sufficiently to allow the 
 solder to set. 
 
 USE OF OXYGEN FOR REMOVING CARBON. 
 
 The use of oxygen for the removal of 
 carbon in cylinders is now very generally 
 employed. The process is one of simple 
 combustion, the carbon burning to a gas 
 in the presence of pure oxygen. This burn- 
 ing is usually attended by a considerable 
 pyrotechnic effect, so that the onlooker is 
 apt to think that an exceedingly high tem- 
 perature is obtained which might injure 
 the cylinder. Such is not the case. The 
 temperature is somewhat below that pre- 
 vailing in the combustion chamber when 
 
168 OXY-ACETYLENE WELDING & CUTTING. 
 
 Fig. 45. 
 
 This cut shows a large casting on an ice machine 
 that was welded. A part of the flange was broken off 
 and the crack extended up into the body of the casting. 
 It was necessary to dismantle, but presented no serious 
 difficulty in welding aside from the fact that the turning 
 of a casting of its size in order to get at every part 
 of the crack was somewhat tedious. 
 
 The entire end of the casting was pre-heated. 
 
CARBON CLEANING. 169 
 
 the engine is running so. that no trouble 
 can come from that score. An analysis of 
 the carbon in cylinders discloses that it 
 contains road dust or silica. The oxygen 
 will not remove this. 
 
 Fig. 46. 
 
 This cut shows a large copper still with longitudinal 
 seams and connections welded. This still was 4% feet 
 in diameter by about 6 feet high. The metal did not 
 exceed ^ of an inch in thickness, and yet on account 
 of the conductivity of the copper it was found necessary 
 to build a coke fire on the inside and cover the outside 
 with asbestps in order to hold the heat. 
 
 To those not familiar with the process 
 it is necessary to impress upon them that 
 oxygen only is used. Acetylene plays no 
 part and is not used, the carbon in the 
 cylinder acting as the only fuel. The equip- 
 
170 OXY-ACETYLENE WELDING & CUTTING. 
 
 meiit necessary is a tank of oxygen, a regu- 
 lator which reduces the pressure, about 12 
 feet of hose and either a special carbon 
 torch or a special tip which is attached to 
 the welding torch. The operation is pre- 
 pared for as follows : 
 
 Fig. 47. 
 
 This' cut shows an armature with shaft beveled and 
 lined up preparatory to welding 1 . In this case the weld 
 was far enough removed from the armature as to not 
 endanger burning the insulation. Where the weld is 
 closer to the armature it is necessary to cover that 
 end with wet asbestos. As the weld progresses, an 
 assistant can from time to time slowly pour water on 
 the asbestos. 
 
 The gasoline tank is cut off and the 
 motor started and allowed to run until it 
 stops of its own accord. This indicates that 
 all of the gasoline in the carburetor has 
 been used up, which is one of the things 
 desired. It is important that no gasoline 
 
,CAKBON CLEANING. 171 
 
 he allowed to remain in the line from the 
 tank to the carburetor, and if there is a 
 vacuum feed, it should be drained. Re- 
 move either the valve caps or the spark 
 plug on the first cylinder and turn the en- 
 gine over until this cylinder is on compres- 
 sion. This means that the piston is at 
 
 Fig. 48. 
 
 This is a large cast-iron cylinder 14 feet in diameter 
 and weighing- 30,000 pounds. A part of the flange was 
 broken off and in addition there were a great many 
 blow-holes in the unbroken part. 
 
 On account of the size, and the fact that the welding 
 was on an -edge, no attempt was made to pre-heat. The 
 broken parts were welded back and the blow-holes filled 
 up. It was impossible to prevent chilling cf the metal 
 and in facing off, an emery wheel was found necessary. 
 
 The welded casting has now been in service several 
 years, giving entire satisfaction. 
 
172 OXY-ACETYLENE WELDING & CUTTING. 
 
 the top of its stroke and the valves closed. 
 The oxygen tank should then be opened 
 slowly and the regulator set at about 15 
 pounds. Drop a lighted match into the 
 valve chamber, insert the copper tubing 
 and turn on the oxvgen. If the flame is 
 
 Fig. 49. 
 
 This shows the head of a large ammonia compressor 
 which was badly broken and successfully welded. Not 
 only was it necessary to stand high pressure, but it 
 must also be ammonia tight and any one familiar with 
 the penetrating quality of that gas realizes that the 
 weld had to be free from blow-holes. The metal was 
 about 3 inches thick and the length of the break 36 
 inches. 
 
 Fortunately, with the exception of about 6 inches, the 
 welding was all in one position. The crack was carefully 
 chamfered and lined up and then pre-heated until red 
 all over. 
 
CARBON GLEANING. 
 
 173 
 
 considerable, reduce the amount of oxygen 
 pressure. 
 
 If the carbon does not seem to burn well 
 and increasing the oxygen pressure does 
 not help, inject just a few drops of oil, 
 kerosene or lubricating. 
 
 Compressed air or a small hand bellows 
 should be used to blow out particles of 
 road dust or grit that remains, and the 
 valve seats should be cleaned with a swab. 
 
 This shows a large fly-wheel which had all six spokes 
 broken, and which was successfully welded. 
 
 In this case the entire wheel, rim, hub and spokes was 
 pre-heated and all but a very little welding was done 
 from one side. In this case it was impossible to keep 
 the bore in the hub true, so that the bore was enlarged 
 and a bushing- inserted. 
 
174.. OX Y- ACETYLENE WELDING & CUTTING. 
 
 The remaining cylinders are treated in 
 like manner. 
 
 It is good policy to have near at hand 
 a fire extinguisher, as the proximity of 
 grease and oils to the flying sparks must 
 he considered. 
 
 COST-CARD. 
 
 Some kind of a time or cost card should 
 be kept where job or repair welding is 
 done. By doing so you will not only have a 
 record of the operation in the event of a 
 dispute, but in a very few months you will 
 have on file a history of a great many dif- 
 ferent jobs, which will be found a great 
 assistance in determining a price should 
 the customer desire it. Few custom weld- 
 ing shops properly take into account what 
 is known as overhead expense. This in- 
 cludes rent, telephones, advertising, post- 
 age, bad accounts, depreciation of equip- 
 ment, failure of welds, etc. At least 100% 
 should be added to the actual labor, gas 
 and material cost to cover the overhead. 
 Unless this is done one will not go ahead. 
 
 If the owner of the shop does his own 
 welding, he should charge this up at the 
 same price he would have to pay did he 
 employ a welder. 
 
 A cost card for repair welding is shown 
 on page 177. 
 
COST CARD. 
 
 17f) 
 
 Fig. 51. 
 
 This is a cut taken of a compartment oil tank used 
 on a delivery wagon. The manner in which the partitions 
 are formed and welded in is described elsewhere, as is 
 also the welding of the filling and drainage plugs. 
 
 The manufacture of these tanks presents no serious 
 difficulties. 
 
170 
 
 Fig. 52. 
 
 This s h o w s 
 p a r t of the 
 frame of a large 
 Hoe printing 
 press. This was 
 broken at the 
 white line near 
 the man's hand. 
 The metal was 
 4x5 In. A 
 pre-heating torch 
 was directed on 
 the break but in 
 snch a position 
 that the main 
 casting instead 
 of the broken-off 
 part received 
 most of the heat. 
 The welding was 
 completed i n 
 only a few hours 
 enabling the cus- 
 tomer to print 
 his paper with- 
 out the loss of a 
 single issue. 
 
RECEIPT TICKET. 177 
 
 uate June 1st, 1916 Shop Ticket No. 50 
 
 Article Single Cylinder 
 
 Kind of Weld 5 inch crack in water jacket 
 
 Pressure uxy. Start 1750 Ibs. in 100 cu. tt. tank 
 pressure Oxy. Finish 1400 Ibs. 
 350 Ibs. 
 
 GAS USED. 
 
 Cu. Ft. Oxygen Used 20 @ 2c $ .40 
 
 Cu. Ft. Acetylene Used 20 @ 3c .60 
 
 LABOR. 
 
 Preparing Hrs. Min. 30 @ $ .80 .40 
 
 Welding Hrs. Min. 30 @ 1.00 .50 
 
 Finishing Hrs. 1 Min. @ .80 .80 
 
 MATERIAL. 
 Rods 
 
 Lbs. Steel @ 
 
 I Lbs. Cast Iron @ .15 .15 
 
 Lbs. Bronze @ " 
 
 Lbs. Aluminum @ 
 
 Flux 05 
 
 Lbs. Charcoal 
 
 Pre-Heating Torch y 2 Hour .10 
 
 TOTAL $3.00 
 
 RECEIPT TICKET. 
 
 Whether the broken easting is brought to 
 the welding shop by a firm using their own 
 dray ticket or by an individual, the welding 
 shop's own receipt ticket should be given. 
 It is important that this receipt ticket have 
 printed at the top the conditions under 
 which the casting is accepted. A sample 
 ticket is shown herewith. 
 
 We guarantee our ordinary class of work, by re- 
 funding the amount paid for the work, if it should 
 break again in the line of the weld within 30 days 
 
178 OXY-ACETYLENE WELDING & CUTTING. 
 
 from date of delivery to owners, or we will reweld 
 again free of charge, parts to be submitted to us, 
 transportation prepaid for our decision. If we can- 
 not succeed in making a satisfactory job, we do not 
 make any charge for the work; our responsibility 
 ends here. 
 
 We are not responsible for the parts left in our 
 charge after 30 days. 
 
 We accept parts only as being of scrap value, and 
 are not responsible for delays of any kind. 
 
 All work is received subject to above conditions and 
 guarantee. 
 
 John Jones Welding Co., 
 No. 250 Order No. 52 
 
 St. Louis, January 10, 1916. 
 Received from Smith Auto Company 
 
 2826 Locust Street 
 1 Aluminum Case 
 
 To be done 1/12/16 Price $15.00 
 
 Taken out by Sam Johnson 
 
 Date 1/12/16 
 
 These tickets should be made in dupli- 
 cate, one being given and one retained by 
 the welding shop, and upon this latter one 
 the customer's receipt is obtained when the 
 casting goes out. 
 
 TABLES AND USEFUL INFORMATION. 
 
 WEIGHTS OP VARIOUS METALS. 
 
 Ave. weight Ave. weight 
 
 of 1 cu. ft. of 1 cu. in. 
 
 in pounds in pounds 
 
 Grey Iron 450 .2606 
 
 Wrought Iron 480 .278 
 
 Mercury 849 .491 
 
 Silver 655 .579 
 
 Aluminum 162 .0932 
 
 Cast Copper 542 .313 
 
 Rolled Copper 555 .321 
 
 Steel 490 .283 
 
 Tin 459 .265 
 
 Zinc 437.5 .252 
 
USEFUL INFORMATION. 
 
 179 
 
 METRIC AND ENGLISH SYSTEMS. 
 
 pound 
 inch 
 foot 
 mile 
 
 1 sq. 
 
 1 
 
 inch 
 sq. foot 
 1 cubic inch 
 1 cubic foot 
 1 quart 
 1 Kilogram 
 1 Millimeter 
 1 metre 
 1 Kilometer 
 1 Sq. Millimeter 
 1 Sq. Metre 
 I Cn. Centimeter 
 1 Cu. Metre 
 1 Litre 
 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 equivalent 
 
 to .4536 
 to 25.4 
 to .3048 
 to 1.6094 
 to 645.2 
 to .09291 
 to 16.39 
 
 .02832 
 1.101 
 2.2047 
 .0394 
 3.2807 
 .6213 
 .00155 
 10.763 
 
 .0610 
 35.3105 
 61.017 
 
 to 
 
 to 
 to 
 to 
 to 
 to 
 to 
 to 
 to 
 to 
 to 
 
 Kilogra ', -, s 
 
 Millimeters 
 
 Meters 
 
 Kilometers 
 
 Sq. Millimeters 
 
 Sq. Meters 
 
 Cu. Centimeters 
 
 Cu. Meters 
 
 Litres 
 
 Pounds 
 
 Inches 
 
 Feet 
 
 Miles 
 
 Sq. Inch' 
 
 Sq. Feet 
 
 Cubic Inch 
 
 Cubic Feet 
 
 Cubic Inches 
 
 TABLE SHOWING THE ORDER OF 
 
 Malleability. 
 
 Gold 
 
 Silver 
 
 Aluminum 
 
 Copper 
 
 Tin 
 
 Lead 
 
 Zinc 
 
 Platinum 
 
 Iron 
 
 Ductility. 
 
 Platinum 
 
 Silver 
 
 Iron 
 
 Copper 
 
 Gold 
 
 Aluminum 
 
 Zinc 
 
 Tin 
 
 Lead 
 
 Tenacity. 
 
 Iron 
 
 Copper 
 
 Aluminum 
 
 Platinum 
 
 Silver 
 
 Zinc 
 
 Gold 
 
 Tin 
 
 Lead 
 
 Infusibility, 
 Platinum 
 Iron 
 Copper 
 Gold 
 Silver 
 Aluminum 
 Zinc 
 Lead 
 *Tin 
 
 To transform temperature readings from Centi- 
 grade to Fahrenheit double the centigrade number, 
 diminish it by one-tenth of itself and add 32. As an 
 example: 100 degrees Centigrade is equivalent to 
 212 degrees Fahrenheit. Doubling 100 gives us 200, 
 deducting one-tenth leaves 180 and adding 32 we have 
 212. 
 
 For changing Fahrenheit into Centigrade the rule 
 is, subtract 32, increase the remainder by one-ninth 
 of itself and take one-half. 
 
 To find diameter of a circle multiply circumfer- 
 ence by .31831. 
 
 To find circumference of a circle multiply diameter 
 by 3.1416. 
 
 To find area of a circle multiply square of diameter 
 by .7854. 
 
180 OXY-ACETYLENE WELDING & CUTTING. 
 
 To find surface of a ball multiply square of diameter 
 by 3.1416. 
 
 To find side of an equal square multiply diameter 
 by .8862. 
 
 To find cubic inches in a ball multiply cube of 
 diameter by .5236, 
 
 Doubling the diameter of a pipe increases its ca- 
 pacity four times. 
 
 Double riveting is from 16 to 20 per cent, stronger 
 than single. 
 
 A gallon of water (U. S. Standard) weighs 8V 3 
 pounds and contains 231 cubic inches. 
 
 A cubic foot of water contains iy 2 gallons, 1728 
 cubic inches, and weighs 62^ pounds. 
 
 To sharpen dull files lay them in dilute sulphuric 
 acid until they are eaten deep enough. 
 
 A horse power is equivalent to raising 33,000 
 pounds one foot per minute, or 550 pounds one foot 
 per second. 
 
 To find the pressure in pounds per square inch of 
 a column of water, multiply the height of the column 
 in feet by .43|. 
 
 A few concerns have expressed a desire 
 to avail themselves of an opportunity to 
 use the limited space in the back of this 
 book for advertising purposes. 
 
 The public can be assured that each and 
 every one is thoroughly reliable and re- 
 sponsible and the attention of the reader 
 is especially directed to them. 
 
ACETYLENE 
 
 IN PORTABLE CYLINDERS 
 OF VARIOUS CAPACITIES 
 
 Commercial Acetylene Welding Co. 
 
 GENERAL OFFICE, 80 BROADWAY, N. Y. 
 
 ATLANTA BOSTON 
 
 SAN FRANCISCO WASHINGTON, D. C. 
 
 CHICAGO 
 TORONTO 
 
GOOD WELDS 
 
 REQUIRE 
 
 PURE OXYGEN 
 
 DISTRIBUTED BY 
 
 AIR REDUCTION SALES CO. 
 
 HIGH PURITY QUICK SERVICE 
 
 ABSOLUTE SAFETY 
 
 BRANCHES IN PRINCIPAL CITIES 
 GENERAL OFFICES 
 
 120 BROADWAY .... NEW YORK 
 
BURDETT 
 
 OXYGEN 
 
 and 
 
 HYDROGEN 
 GAS 
 
 Uniformly 99% P*re 
 
 PROMPTLY SUPPLIED BY PLANTS LOCATED 
 IN THE PRINCIPAL INDUSTRIAL CENTERS. 
 
 Main Office: 
 
 ST. JOHN'S COURT AT FULTON STREET 
 CHICA GO. 
 
 PLANTS: 
 
 CHICAGO 
 DETROIT 
 CINCINNATI 
 LOGANSPORT 
 ST. LOUIS 
 
 DENVER 
 SALT LAKE 
 SAN FRANCISCO 
 LOS ANGELES 
 FORT WORTH 
 
 PHILADELPHIA 
 WILMINGTON 
 PITTSBURGH 
 CHATTANOOGA 
 OKLAHOMA CITY 
 
 The Largest Producers of the PUREST Oxygen 
 in the World. 
 
PURE OXYGEN 
 
 and 
 
 HYDROGEN 
 
 Made by the Electrolytic Process 
 
 Welding and Cutting Apparatus 
 Carbon Cleaning Outfits 
 
 A full stock of welding equipments is 
 carried. It will pay you to write for 
 prices. Our Service Department is at 
 your service. 
 
 LOGANSPORT OXYGEN CO. 
 
 LOGANSPORT, INDIANA 
 
 OHIO ELECTROLYTIC OXYGEN CO. 
 
 CINCINNATI, OHIO 
 
in- 
 
 formation of 
 
 working* 
 for a 
 
 S: 
 
TO THE TRADE 
 
 Our firm is the largest in this country 
 manufacturing flame welding and cut- 
 ting apparatus exclusively. 
 
 In 1913 we were given the Highest 
 Award and Gold Medal at the Me- 
 chanic's Fair held in San Francisco, and 
 again in 1915 we were awarded the Gold 
 Medal at the Panama-Pacific Interna- 
 tional Exposition. Buy the best it is 
 cheapest in the long run. 
 
 We manufacture complete lines for 
 jobbers and manufacturers who do 
 not make complete lines. Let us fig- 
 ure with you. 
 
 Henderson-Willis Welding & Cutting Co. 
 2305-7-9 N. llth Street 
 St. Louis, Mo., U. S. A. 
 
I L L I 
 OXY-ACETYLENE 
 APPARATUS 
 ELDER 
 
 s 
 
 Manufacturers of Scientific 
 
 Welding Torches 
 Cutting Torches 
 
 Duplex Welding and Gutting Torches 
 Lead-Burning Torches 
 
 Carbon-Cleaning Torches 
 
 Oxygen Regulators 
 Acetylene Reducers 
 
 Pressure Gauges 
 
 Acetylene Welding Generators 
 Acetylene Pressure Tanks 
 
 Gas Pre-heating Torches 
 
 Kerosene Pre-heating Torches 
 Hand Trucks for Portable Outfits 
 Welding Rods of all kinds 
 
 Welding Fluxes of all kinds 
 Welding Goggles 
 
 Write for Catalogue 
 
 Henderson- Willis Welding & Cutting Co. 
 
 2305-7-9 N. llth Street 
 St. Louis, Mo., U. S. A. 
 
SUBSCRIBE TO 
 
 The Welding Engineer 
 
 IN YOUR PLANT there is a man who 
 needs timely and accurate information about weld- 
 ing. He should know what is being done in other 
 plants to reduce costs and increase efficiency. No 
 matter what your welding problem may be The 
 Welding Engineer is the best source of information, 
 the best adviser you could have. Every phase of 
 welding, both manufacturing and repair problems, 
 is discussed fully in this valuable monthly publica- 
 tion. The best authorities in America on the 
 subject of welding are regular contributors. 
 
 Oxy-Acetylene-Electric-Thermit-Carbo- 
 Hydrogen and Other Systems 
 
 Every process of welding is discussed by The Welding 
 Engineer. Arc Welding, Electric Butt, Spot and Seam 
 Welding, Oxy-Acetylene, Carbo-Hydrogen and the Thermit 
 System, in fact every known process of joining metals is dis- 
 cussed. Cutting metals is an important subject. Study The 
 Welding Engineer and save gas and time. Welding and 
 Cutting are subjects somebody in your plant should study. 
 
 Price $2.00 in the United States^and Canada. $2. 50 abroad. 
 
 Write for free sample copy for convincing proof that 
 The Welding Engineer is indispensable in your business. 
 
 The Welding Engineer 
 
 Edited by L. B. Mackenzie 
 
 608 So. Dearborn St. 
 CHICAGO 
 
Oi 
 
YA 01496 
 
 46899? 
 
 UNIVERSITY OF CALIFORNIA LIBRARY