Modern welding

By C W BRETT
(Managing Director of Barimar Ltd.)

There was a time, and it was not very long ago, when welding was regarded as a sort of glorified soldering, or as a process about as efficient as brazing. This view, which was commonly held by a large number of capable engineers and others, may be accounted for by the fact that a large amount of repair and reconstruction work was undertaken by ordinary engineers or mechanics, as a sort of side line or adjunct to their regular work. There was, however, another reason which, if it did not create, at least kept alive the prejudice, and that was the actual and undeniable limitations of the process itself.

In the last two decades all this has been changed ; in place of the tyro or occasional welder fiddling about with a wholly inadequate equipment and attempting the (then) impossible, we have the specialist. In place of one or two undeveloped and unreliable fusive processes, we have now six distinct fusive agents which have been brought to a wonderful pitch of perfection by endless research, investigation and experimentation by metallurgists and scientists all over the world.

As a result, the popularization and utilization of welding has increased to a truly remarkable extent, and the former prejudice, if not yet dead, “is doomed and doubly damned.” As a well-known engineer said recently before an audience of technicians : ” If a weld fails, under normal load strain, the failure is due to the deficiency of the operator, never of the process. A scientifically welded member or component should in all circumstances function as efficiently as a new member of similar dimensions and material.” The man who declares that “you can’t expect more than 75% efficiency from a welded part” is either woefully ignorant of modern welding practice and its potentialities, or he himself is inexcusably lacking in skill and experience. The only alternative is that he is attempting metallic recreation or mechanical reconstruction work with insufficient material equipment or by the application of a fusive agent unsuited to the particular metal or machine with which he is dealing.

Welding to-day implies (a) the direction of an expert whose knowledge of metallurgy and thermics enables to select the process from which, in any given circumstances, the best results may be anticipated, and to supervise and control the application, (b) the services of an operator of skill and experience in handling each and all of the industrial metals by any of the fusive processes which nowadays constitute the specialist’s equipment, and (c) the possession of the most up to-date apparatus and appliances used for high temperature treatment. Without these minimum essentials all welding becomes a pure farce if not an impossibility. It is as reasonable to expect an apothecary’s assistant, armed with one prescription, to cure all human ills, as it would be to expect a journeyman engineer equipped with a one-process welding set to tackle the complete reconstruction of plant and machinery of all descriptions. In the former case the death of the patient is inevitable, in the latter the destruction of the machine or component is a foregone conclusion.

From the modern viewpoint the facts are these : Scientific welding can be readily and rapidly employed to effect the partial or total restoration to 100% efficiency of mechanical devices of every description and size, used for whatsoever purpose, and fabricated of each or all of the industrial metals, including high speed steels. It can be relied upon to effect a cash saving of from 50% to 90% on the cost of replacement, and a proportionate saving in time. It is not merely capable of restoring a unit or component to its former efficiency, but can be used to increase strength or dimensions to any required degree, to make good fractures, wear and tear or other damage, to eliminate design or material weaknesses, and to maintain units or components at “peak performance ” pitch.

It would be manifestly absurd, in speaking to readers of MOTOR SPORT to attempt to disguise the many problems and dangers attendant upon the submission of high grade metals to temperatures ranging between 1200 and 5500 degs. F. The difficulties by which the welder is confronted at every stage of the work are increased a hundredfold when the work relates to the welding of steels containing varying proportions or combinations of zirconium, tungsten, nickel, chromium, molybdenum, titanium, vanadium, manganese, etc., etc. Indeed, in such cases, the slightest miscalculation or mishandling will almost assuredly result in robbing the metals treated of those particular and peculiar qualities they were expressly intended to embody, and in reducing their efficiency to nil. Many serious accidents, involving heavy material loss and possibly loss of life, have been caused in this way. It is sometimes said by those unfamiliar with modern achievement that welding is only suitable for certain classes of work or certain metals. This is quite erroneous. A specialist should be able to tackle practically any machine or any industrial metal under a definite “money back” guarantee. This point is worthy of special note because it is the hall mark of the acknowledged expert. Refusal to work under these terms practically amounts to a confession of incompetence. If a welder states that he is a specialist it is not unreasonable to expect him to justify his claim by sound performance; on the other hand, it is not unfair to refuse to accept the credentials of an operator who seeks to evade a perfectly legitimate challenge.

The value of scientific welding to the motorist may be gauged by the following incomplete list of repairs and reconstructions which are now regarded by the specialist as ordinary routine jobs. Fractured, scored, worn or damaged cylinders (without enlarging the bore or fitting new pistons) combustion heads, water jackets, crank cases, cranks, cam shafts, transmission shafts, gear boxes, gears, axle shafts, axles, hubs, wheels, radiators, chassis frames and members, light metal sections, mudguards, lamps and all garage tools and accessories. Actually there is scarcely a metal part from the radiator cap to the luggage grid which, in the hands of a skilled operator, cannot be reconstructed equal to new. The age, make, size or condition of the unit or component is immaterial ; the only thing that does matter is the selection and proper use of the fusive process best suited to the material and the job in question.

In America, Germany, France, Belgium, and, indeed, in most manufacturing countries scientific welding is being increasingly used for the reconstruction of plant and machinery of every description used in all trades and for all purposes, and also in the fabrication of metal devices of all kinds, many of which are called upon to withstand exceptionally heavy stresses and strains suddenly imposed.

That welding has now reached a pitch of perfection which admits of no debate is proved conclusively by existing statistics showing that the breaking strain of a welded member is not less than that of the original part, but, in conjunction with this statement, it must not be forgotten that high efficiency demands the services of the highly efficient.

Any fool can weld ; but the welding of any fool is about as reliable as ” a cat in a pantry.”