IIW History 1948-1958

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2. WORK ACCOMPLISHED. The work carried out by Commission II is described below under the existing Sub-Commissions. A. Sub-Commission A « Hydrogen in Weld Metal » . The principal subject of study has been the problem of determining hydrogen in weld metal, this problem being considered in conj unction \Vith the evaluation of the water coutent of elecLruue coverings. On the preparation of the draft code of syrnbols fo r covered electrodes fo r the welding of mild and low alloy steels, which will be mentioned in connexion with the work of Sub-Commission E, the question of the hydrogen content of weld metal was raised with regard to basic electrodes. lVIany tests \Vere carried out and a proposed method of determination was prepared for transmission to the Committee I SO/TC 44 (\i\ elding) SC 3 (Filler Metals and E lectrodes). In the light of the comment s made in this connexion by ISO, the problem was again considered by Commission II and, in particular, by its Sub-Commissions A and E. In the near future, fresh proposals will certainly be put forward regarding the conventi onal method for the determination of hydrogen. The study of the effects of hydrogen on the properties of weld metal has been made possible as a result of a large number of contributions from membe rs of the Commission. For example, mention may be made of those from Messrs. NOREX and ERIKSOK (Sweden) on the formation of « fish-eyes » considered as brittle fractures initiated by over-saturation with hydrogen. Vi e may also mention the influence of storage time at room temperature on the hydrogen content and mechanical properties of the weld metal. It seems that, in spite of the reduction in the number of « fish eyes » and the improvement in the results ol tained by tensile tests, the bad effects of hydrogen do not totally disappear even after several months. A report by l\ifr. HUMMITZSCI-I (Germany) on the this subj ect, Effect of Storage Time on Hydrogen Content and Nlechan,ical Propert1:es(1), has been recommended for publication. Various contributions on the effect of hydroge n on the results of impact tests have also been made over the last few years. The work of the Sub-Com– mission will also benefit from papers on this subject p resented at the publi c session at Essen (2), several of which were prepared by members of Commission II . R Sub-Commission B « Testing and Measurement of Arc Welding Equipment » , At the Paris meeting in 1950, it was evident that the first point t o be con– sidered was the method of specification of arc welding apparatus. As a result of an investigation carried out by Sub-Commission B in which eleven national standards were compared, Commission II was able in 1952 at Goteborg t o take three decisions : r, To transmit t o I SO/TC 44 proposals regarding the fundamental po ints , numbering eighteen, to be t aken into consideration in the preparation of an in– ternational specification. 2. To place on the programme of work an experimental investigation on Yarious types of \Yelding apparatus, the purpose being to verify, in heating tests in intermittent periodic service, the influence of the length of the cycle on the heating elements, the duty cycle remaining constant.

(1.) Document II-7-57. (2) These papers a re 111entioned in chapter\".