Part 2 — PLAN No. 1139. OXY-ACETYLENE WELDING

Acknowledgment

This monograph was prepared by Edward Matteossian, Special Agent for the Federal Board for Vocational Education, under the direction of Charles H. Winslow, Chief of the Division of Research. Acknowledgment is due to Dr. John Cummings of the Research Division for editorial assistance.

What the Welder Does

He handles a torch, or blowpipe, at the tip of which a flame is produced by the burning of a mixture of two gases—acetylene and oxygen. A high degree of heat is produced by this flame, which can be concentrated at any point by proper handling of the torch.

The welder’s activities may be divided into two operations—welding and cutting.

Welding

In welding, metals, like or unlike, are joined together by melting them until they fuse, “adding material” being used where it is required. The welder also builds up worn parts or adds metal where it is lacking. Common metals which can be treated by this process include the following: Cast iron, steel, malleable iron, aluminum, copper, brass, bronze, lead, and nickel. Precious metals also can be welded. Each metal has its peculiar characteristics and mode of treatment, and the welder who would turn out a good job must master the special technique for handling each metal.

Welding forms the larger part of the welder’s activities. It is much more difficult than cutting, and also has a wider field of application.

Cutting

Cutting can be learned in a few hours. It is restricted in its scope, as it can be used only on steel and wrought iron. The cutting torch is similar to the welding torch with the difference that it is equipped with a special outlet for oxygen under pressure. The operator turns on his usual welding flame until the object is heated to a cherry red, and then presses a device which turns on the oxygen, causing the metal to burn away rapidly. The torch is then advanced slowly along the line of the cut to be made. By practice comes the knack of steadiness and of moving the torch at just the right speed to cut clear through the metal—not too fast for complete penetration, nor too slow, causing loss of oxygen.

Work in the Open and in the Shop

Where the job can not be brought into the shop, welding and cutting are done out of doors, and may be carried on under all conditions of weather. Very commonly the process is used in cutting scrap, wreckage, and piling, and in welding piping and mains.

Inside work varies from shop to shop according as the shop is part of a manufacturing plant or of a foundry, or is purely a job welding shop.

Some account of the common uses of the processes in different industries is given in the section below on “Industrial Applications.” In steam and electric railway shops and yards, in shipbuilding, in the manufacture and repair of automobiles, in installing pipes and mains, in sheet-metal and metal plate work, in the manufacture of furniture, containers and other metal products, and in foundry work, welding and cutting is being extensively used to-day, and each day the welder’s field of operations is still further extended.

What Localities Need Welders?

The answer is: All localities where industrial plants are located, or where street railways are operated, or where farm machinery and implements are made or repaired, or where automobiles are used or built. Such localities will probably include your own home town or some town not far away from home.

The Welder’s Tools and Equipment

The numerous makes of torches on the market are of two general types—the medium, or positive, pressure torch; and the low pressure, or injector torch. Practically all the oxygen used comes in compressed form in cylinders. Acetylene is more commonly generated on the premises, owing to the cheapness of this method. It is piped into the buildings and is always readily accessible. Generators, like torches, are of various makes, but they vary in type to correspond to the two kinds of torches, i. e., pressure generators, and low-pressure generators. Generators are automatic in their action, being controlled by the flow of gas. Where the gas is not generated in the establishment, and especially in outdoor work, dissolved acetylene is used. This comes in cylinders which are filled with porous material and contain acetone, a liquid, in which the gas is dissolved under pressure.

Welding equipment varies according to circumstances. In general a welding unit includes welding and cutting torches; hose and connections; oxygen and acetylene regulators and gauges; a supply of various tips; filler rods; goggles; friction lighters; gloves; asbestos sheets; fluxes; hand tools, such as pliers, files, hammers and cold chisels; welding table; preheating arrangement; fire brick; carbon blocks; and V-blocks. It may include also, hand shear, anvil, hand forge, bench and pipe vises, emery grinders, drill press, hack saw, jigs, lathe, hoist, and work bench.

Practically all of the necessary equipment is furnished to the welder, sometimes with exception of goggles, gloves, and overalls or leather apron, which the welder may have to obtain for himself.

Why Take Training?

The aim of re-education is to turn out a good welder who has not only the manipulative skill, but who in addition is well-grounded in the necessary theoretical knowledge. It can not be too strongly pointed out, in the view of the highly unsatisfactory method of turning out welders obtaining in the past, that the course can not be too thorough. The need is for good welders, not for half-trained men. Really good welders in this country are not many, and there is in this field a splendid opportunity for the well-equipped man, but for him only. An employer will always be looking for a better man if he has a half-trained man on the job.

Overcoming Your Disability

The question is not primarily one of the handicap, but rather of the man behind the handicap. It is not the exception, but rather the rule, that a partially handicapped person, endowed with ingenuity will, even though at a disadvantage, beat the sound man who does not possess any ingenuity. This is borne out by numerous instances of foreign experience in re-education.

This applies, of course, especially to the less serious disabilities and not at all to those which are manifestly debarring. In the case of a welder, the latter would include blindness or defective vision, paralysis, shell shock and nervous disorders, loss of both arms or hands, tuberculosis, ankylosis of the upper members, spinal trouble, stiff neck, and dizziness.

Ankylosis of the knee or wrist might be overcome to some extent. Amputation of one leg will simply limit the field of activities. Where both legs are gone it would still be possible to enter some specialized field where work at the bench is all that is required. In such cases, however, it might be advisable to take up soldering or electric resistance welding. Loss of limbs would be an embarrassing handicap for most jobs, and prohibitive for outside work which necessitates climbing, crawling, stooping, or getting into abnormal positions. Men who have trouble in getting about should not enter this field. Only physically sound men should undertake work in confined spaces, in a boiler for example. One partially amputated arm would probably not be deterrent. Indoor work is manifestly unsuited to men with weak lungs, as the air in the shop is generally more or less heated and vitiated. Outdoor work might be pursued with benefit. Men with weak backs would generally be at a disadvantage. Kidney or intestinal trouble might or might not be deterrent, depending on the gravity of the trouble and the degree to which physical stamina and general health are affected. Rupture would not be a handicap except where heavy work is to be done, and in that class of work there is usually a helper around. Impairment of efficiency due to loss of one eye, which may make difficult the acquirement of precision in distancing the flame from the material to be welded, may nevertheless generally be overcome.

The welder must have one good arm and hand with which to hold and manipulate the torch, and enough of a stump left in the other arm to be capable of using the filler rod and of puddling. Amputation, ankylosis, or paralysis of a finger or two are not prohibitive, so long as the proper grip and manipulation of the torch can be preserved.

Devices for Overcoming Handicaps

Special “automatic pincers” are being used by French autogenous welders, to take the place of a missing hand, for those who have lost only part of the forearm. Drawings of this appliance are here given. The upper drawing shows the opening of the pincers through extension of the forearm, and the lower two drawings represent modification of the upper pincers for the use of welders.

Those who are incapable of using their hand through any cause are equipped with a special tool holder which is attached to the forearm.

Where the handicap consists of the loss of an arm, cutting may be taken up to advantage. There is restricted field of employment for disabled men in the operation of automatic welding or cutting machines.

Safety and Hygiene

As in other occupations, there are in welding, certain safety measures to be taken to avoid accidents. These are clearly defined and are made an integral part of the welder’s training until observance becomes automatic.

This applies, of course, to the man who is physically sound as well as to the disabled. In the case of the handicapped, the matter becomes one of ascertaining if the disability interferes with the carrying out of these safety measures; and if so, if the difficulty can be overcome. If not, some other occupation must be selected. In the welder’s case, however, these precautions are mostly “don’ts,” and do not present serious difficulties to be overcome.

Acetylene is not poisonous and the impurities in the gas which are poisonous are not present in sufficient quantity in the American carbide to be dangerous. The characteristic odor of the gas is a protection against fire, explosion, and suffocation. One cubic foot thoroughly mixed with 10,000 cubic feet of air can be detected.

How Previous Experience Helps

In selecting any vocation, a man’s former occupation must be carefully taken into account, and particularly is this true in the case of welding. Previous experience, training, and education are such important factors in the student’s success or failure that particular attention should be paid to them. Experience as a blacksmith, machinist, boilermaker, patternmaker, sheet-metal worker, molder, electrician, and in kindred occupations will be in every case of great value.

All experience in handling metals, as well as all mechanical experience is a valuable asset. For a man who has had such experience, it will be comparatively easy to become a good all-round welder. It goes without saying that no disabled man should take up the course unless he feels an interest in the work or in some special branch of it. It is this interest coupled with ingenuity which will make it possible for the welder to handle new problems successfully and to devise better and more efficient ways of doing things.

In the case of a former welder who is capable of taking up his former vocation, a short course of training will suffice. A former welder whose handicap prevents him from taking up his old trade may, with the proper training and necessary qualifications, become an excellent teacher, a welding foreman, or a superintendent.

Are Welders Going to be Needed?

The process is of comparatively recent application, dating back to about the year 1904. Its growth has been extremely rapid, especially of later years, as regards development of technique, extension of its applications, and perfection of apparatus. Regardless of this progress, however, it is no exaggeration to state that the process is as yet in its initial stages, and that in the near future its field of utility will be greatly extended. As contrasted with the growth of oxy-acetylene welding, the supply of good welders has lagged far behind the demand. Unlike European countries, this country has only lately come to realize the importance of well-grounded, thorough, practical training for prospective welders. In view of these two factors—the remarkable expansion of the process and the shortage of welders—prospects look bright for the future.

Qualifying as a Teacher of the Welding Process

In any occupation where the demand for labor is increasing rapidly, there is bound to be a demand for men to teach the processes and practice of the occupation. If you master the trade you yourself may qualify as a teacher.

Getting to Work after Training

In contemplating placement after training the following factors are to be taken into account:

Your choice of a field.

Your special fitness.

The industrial demand.

It is the disabled man’s privilege to decide what he will specialize in and he will be allowed the freedom of choosing which branch of welding he will take up, such choice being of course subject to the guidance of the vocational adviser.

Most welders will exhibit a tendency toward some special branch or type of welding, even while they are learning the art. The instructor will keep in constant touch with the pupil during the course to determine if there is such a trend in him, and if so to encourage it. Some take to one metal in preference to others; some to one operation in preference to others; some may give evidence of ability as all-round welders.

The demand for welders is so varied that knowing the demands in general it will in most cases be possible to satisfy preferences and special aptitudes. This will be the aim always.

If as a trained welder you desire to get started on your own hook, several questions will arise in your mind?

Where shall I be located?

What are the demands of the locality in which I shall live?

What is my fitness for the work?

How about the necessary equipment?

The locality should be such as to give you ample opportunity to make good. It might be hard for you to go against much competition at the start. Likewise, to act as a pioneer of the industry in some locality which knows nothing about the work, might not be desirable.

In placing retrained welders, local demands will be carefully considered to the end that no man shall be placed where he may have work coming in which he is not capable of handling efficiently.

What if You Do not Take Training?

You will not be a real welder; probably you will not get a chance to try your hand at manipulating the torch at all. If you do get a chance you may get hurt or hurt others trying to weld without training for the trade. Train for it, and then go to it, and if you fail come back for more training or for training in some other trade.

Industrial Applications

Some idea of the wide range of application of the oxy-acetylene processes may be gained from a brief survey of their uses in several industrial fields.

PLAN No. 1140. STEAM RAILWAYS

Oxy-acetylene welding is used in the shops of practically every railroad in the country as a means of reducing cost of repair and of reclaiming worn parts. Each craft usually does the welding of metals that originates in its department: Blacksmiths handle wrought iron and steel; boilermakers, boiler plates and flues; machinists, cast iron; coppersmiths, brass pipe work.

The process is generally used in the reclamation of broken engine frames, damaged cylinders, broken spokes in driver wheels, cracked valve chamber bushings, broken steam and exhaust pipes and air pump heads; in mending cracks, cutting out and welding patches on side sheets of fire boxes, flue sheets and door collars; in welding front end doors when damaged, engine truck frames and cradles, frame braces and brackets, tender bolsters, guides, and pedestals. The process is used to some extent also in building up worn diamond crossings and frogs. Both cutting and welding are used in the upkeep and repair of steel cars.

At the scrap yard the welder cuts up old boilers and other scrap for salvaging.

PLAN No. 1141. ELECTRIC RAILWAYS

Applications of the process by electric railways are similar to those by steam railways. There are, however, more opportunities for doing welding at the table. Of such a nature are restoring of armature bearing housings and frame heads, worn axle seats for motors and axle caps, journal boxes, pinion seats and keyways, brush holders, trolley bases, and third-rail shoe castings. Heavy broken parts such as truck frames, drawheads, brake hangers and body bolsters are repaired. To some extent the process is used also in bonding rails and in welding steel trolleys. Most of the work is handled in the shop, where, however, electric welding is coming into more general use, owing to the availability and economy of electric power.

PLAN No. 1142. SHIPBUILDING

Extensive use is made of the process in cutting all kinds and shapes of steel plate. Hydrogen is very generally used, instead of acetylene, and welding machines have been introduced. Welding proper is more generally applied in reclamation work, damaged or broken parts of the ship and of its machinery and propellers being often welded by this process.

Electric arc welding is fast coming to the front in this field, except for cutting where the gas process can not be replaced.

PLAN No. 1143. AUTOMOBILE INDUSTRY

Oxy-acetylene welding of automobile parts is not in general very difficult, but as in all other welding mastery of fundamentals is here also essential to success. The work is varied in character, including cast iron, aluminum, steel, and wrought iron welding.

The process is extensively used in the repair of automobiles, and to a lesser degree in their manufacture. Both the industry itself and the repair work provide excellent fields for the prospective welder.

Repair work is done generally in either a job welding shop, where a number of welders are employed and where all kinds of welding is carried on, or else in a garage or automobile repair shop where a welder is employed to do the necessary work. In small communities the welding shop is usually run by one man who owns it and who does all the welding. In the large welding shops acetylene is generated; in other cases dissolved acetylene is used. A welder who is expert in the welding of aluminum is particularly valuable in this work.

In manufacture, the work is done in the shop. It is often simple and well suited to workers who must elect a sedentary employment. The process is broadening its scope in this field.

Closely related to the automobile is the motorcycle. A number of its parts, such as handlebars, special jigs and muffler heads, are welded in manufacture. In repair work the scope is somewhat similar to that of automobile repairing.

PLAN No. 1144. PIPE AND MAIN WORK

In the welding of pipes and mains, the process is finding increased application and this field presents good prospects of expansion in the future. Extensive work in this country as well as in Europe, where it is more largely used, has demonstrated that welding is not only the most economical method but as well the most efficient in that leaky joints are eliminated. Welding does away with threaded joints, and thus makes possible the use of much lighter pipe, since there is no need for making allowance in thickness for threading. Moreover, joint couplings are dispensed with. The expense saved in maintenance alone is tremendous, as the joint is water-tight and there is therefore little likelihood of trouble arising from leaks. In making connections, Y’s, T’s, crosses and drips are made on the spot, being cut out of odd lengths of pipe and fitted together. This effects an economy in that these odd pieces are saved.

The process has its greatest application in the welding of gas, steam, air, oil, water and ammonia pipes and mains, and the work is chiefly outside work, although it is used to some extent on interior pipe connections. Special fittings or connections may be welded in the shop. Outdoors welding is generally performed on sections of pipe while above the ground, the whole section being finally lowered into the ditch. The welding of these several sections to each other has to be done in the ditch or trench, a pit being generally dug in order to give the welder sufficient room for carrying on the work. Obviously this work requires suppleness in the worker.

Where there is a large amount of welding, the apparatus most commonly used is a portable generator, with which is mounted a set of oxygen tanks. In other cases a small two-wheeled truck carrying one oxygen and one dissolved acetylene cylinder may suffice.

In this kind of work, the welder is generally assisted by one or two helpers who do the heavy work, placing, holding, and turning the pipes while the welder keeps on welding. Some overhead welding is done which forces the welder to assume a strained position.

PLAN No. 1145. SHEET METAL

Welding sheet metal is an important application of the process, which is superseding to a large extent riveting and soldering. Very careful work may be required but in the main the work is not particularly difficult, and it can be easily mastered if the training given is thorough. Electric resistance welding, however, is superseding oxy-acetylene in many manufacturing operations.

PLAN No. 1146. METALLIC FURNITURE

Extensive use of oxy-acetylene welding is made in the manufacture of metallic furniture and in kindred trades. Welding is an efficient and economical way of joining various parts together, as well as of making the parts themselves. The work may be more or less routine and much of it is done at the bench. This is a comparatively easy type of welding, in which a man can become proficient in a short time. It would be eminently suited to the welder who has trouble in going about or who is easily fatigued, and who would be better off in some sedentary work. The process is largely used in the manufacture of steel desks, chairs, filing cabinets, office safes, stepladders, and surgical, hospital and dental furniture.

PLAN No. 1147. CONTAINERS

Welding is fast superseding old methods in the manufacture of containers of various kinds out of sheet metal. In this class is included the manufacture of steel barrels, range boilers, kitchen utensils, light air tanks, and storage tanks. This kind of work needs a well-trained man on the job. Except in the case of larger objects, the work can be done at the welding table, and it is not of a straining nature.

PLAN No. 1148. METAL PLATE

Metal plate welding is quite similar in its scope to sheet metal work. It is largely used in the manufacture of ammonia and air receivers, vacuum driers, steam driers, and vats. The process is not used in boiler work to any extent, as the consequences of a faulty weld might be extremely serious.

PLAN No. 1149. FOUNDRIES

In steel foundries the process is extensively used in cutting away risers, gates, and heads from castings. As compared with the old method of cutting with a saw, the gas process is much quicker and much more economical. This sort of cutting work is simple and does not require great dexterity. The welder should be capable of bending over or assuming more or less cramping positions, as he has to work on the castings in positions in which they have been left on the floor. Welding is almost universally used in the reclamation of defective castings, and by this process castings are saved which for some slight defect would have been consigned to the scrap heap. The process finds application also in the welding of blowholes, cold shuts, porous spots, and cracks. It is used to some extent in manufacture, two parts being cast separately and joined by welding.