IIW History 1948-1958

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C. Establishment of Recommended Practices for Diffe rent Processes of Res istance Welding. In several countries, an attempt has been made to guide the user in the application of resistance \Yelding processes and it is thus that different organisa– tions and persons have published documents under the name of « Recommended Practices », « Codes of Practice », « Recommended Settings of Control », etc. When closely examined, these publications show appreciable di' ergencies one from another. At first sight this \Yould appear curious, because it might be thought that in a given case there is only one \Yay of making a good resistance " ·eld. In fact this is not so. The main parameters in the different methods of operation (dimensions of the parts and of the ·IYeld itself, the \Yelding time, current and pressure) a re inter-dependent. There does not exist, for each of them, a precise recommended value for a given case, but rather teps of adjust– ment \Yhich enable good results to be obtained by means of various combinations of the cl ifferent parameters. If one adds to thi that, from one country to a nother , the order of magnitude of the means at hand to re olve the same problem can be very different, in particular as regards electrical pO\ver, it is not surprising that the different documents published have sho\\·n differences. It therefore appeared desirable to attempt to find a common basis applicable to the generality of applications. It was for this reason that Commission III undertook the preparation of recommended practices for issue under the auspices of the IIVV. r. Spot W elding. In 1950, on the basis of the recommended practices published by the American \\-elding Society, those of the British Welding Research Association and of work undertaken in the United Kingdom by HIPPERSO~ and WATSON, Commission III establisehd a table of recommended settings for spot welding for thicknesses of mild steel which did not exceed 3.5 mm (1/8"). However, as the technique of spot welding has considerably evolved since that time in the direction of using more and more rapid cycles with higher power and shorter welding times, the Commission, at the 1957 meetings, made provision for the revision of the recom– mended settings established in 1950. 2 . Profection Welding. A method of assembly which is particularly suitable to mass production, projection welding is developing very rapidly and it has seemed advisable to provide those who use it \.-vith a reliable guide. This is the task of Sub-Commis– sion B under the Chairmanship of :Mr. BYLIN (Sweden). The basic documents used by the Commission are : « Recommended Practices n of the American 'vVelding ociety, publication 1' 30 of the British Vi elding Research Association, Pro– fection VVelding of M ·ild Steel, as well as the observations of the Commission on these documents, in particular those from Sweden. The document prepared by the Sub-Commission is in the final stage of preparation and will probably be recommended for publication at the 1958 meeting. 3. Flash B itlt TVelding. Sub-Commission C, under the Chairmanship of l\Ir. KLOPFER'l' (Belgium), is responsible for preparing the recommended practices for flash ;velding. It has used the document of the American \iVelding Society mentioned above, publicat ion T 27 of the British Welding Research Association, and various Belgian, Swedish and German documents. Its programrne of work is very extensive and includes the drawing up of recommendations for the flash welding: