The basic materials in all Tuffaloy electrodes are produced to rigid standards of quality and uniformity. The superior performance of these electrodes in your plant depends upon their correct application to the particular job, and proper maintenance in service. Many factors affecting electrode cost and useful electrode life are briefly outlined below.
PART TO BE WELDED
Layout the part for resistance welding. Designing engineer, welding engineer and production man in charge of welding should cooperate in securing a better product at lowest cost.
Correct design permits the use of standard straight electrodes; or standard offset or standard angular holder if the straight approach is not possible. Special shaped electrodes cost more, and the difficulty of cooling the electrode is amplified. Single spot, multiple spot, projection, or other method may be accurately chosen to achieve lowest cost. Consult the R.W. M. A. Manual.*
MATERIAL TO BE WELDED
The weldability of the materials can be determined by consulting your material supplier, and by reviewing recommendations covered in the R.W.M.A. Manual.* Surface conditions, rust, oil, dirt, and, on many articles, oxide film and even handling marks have a decided effect on weld quality. Cleaning may have to be part of the welding job in some cases.
WELDING EQUIPMENT AND CONTROL
A welding machine of reputable quality, purchased for a particular application will be correctly designed both electrically and mechanically, and will be supplied with the correct control equipment and electrodes for the work. On machine change-overs make sure of adequate electrical and mechanical capacity, and see that the necessary controls are provided. Consult us when redesigning or revising your choice of electrodes.
STANDARD GAUGE CHART
THICKNESS IN DECIMALS OF AN INCH
Gage No. Manufacturer's Standard Gage No. Manufacturer's Standard Gage No. Manufacturer's Standard 3
The RWMA tip numbering system has generally replaced the old Morse taper numbers with new "RW" numbers, and has added two new sizes, as the chart illustrates.
ELECTRODE LIFE SAVERS
1Use standard Tuffaloy electrodes with Tuffaloy ejector type, self-adjusting tube, water-cooled electrode holders wherever possible. Avoid special or irregular shapes for lowest cost.
2 Use ample cold cooling water as close as practical to the welding contact surface, properly circulated at a minimum of 30-psi pressure, and supplied at a rate of at least 1-1/2 gallons per minute.
3 Be sure to select the proper type and size of electrode, taking into consideration electrode pressure, contact area of electrode, gauge, and nature of material to be welded. Consult the R.W.M.A. Manual* or your Tuffaloy field engineer regarding recommended practices. Overloading as well as overheating shortens electrode life.
4 Good welds depend upon properly maintained electrodes which assure an accurate surface contact. Keep tapers clean and dress electrode faces with lathe, emery paddle or fine file. Use castor oil or graphite grease to facilitate tip removal, and avoid application of insulators such as white lead and other materials.
* Resistance Welding Manual, published by the Resistance Welder Manufacturers Associations, 1900 Arch St., Philadelphia PA 19103.