IIW History 1948-1958

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F . Control of Welding Parameters . In this field, Commission III h as had the opportunity of studying and app roving t wo reports. The first , submitted in 1952 by Belgium (r) , describes an elect ronic apparatus fo r measuring the welding current, and which utilizes fo r the det ection of this current, a magnetic amplifier (t ransduct or) with a circuit closed by an air gap. This apparatus also includes an elect ronic device t o measure t he welding t ime. The second , prepa red by France (z) and entitled , Contribittion to the Stitdy of the Control of the Parameters - Voltage - Citrrent - Pressitre - T ime in R es·istance Spot Welding has been recommended for publication . It contains the description of methods fo r recording and measuring the p aramet ers, methods \vhich are based essentially upon t he use of a st ylus oscillograph of which the measuring circuits are connect ed t o various devices which permit the determin– ati on of the welding p aramet ers. The p receding chapter gives an account of the work in hand in the fields where concret e results have been obt ained in the form of documents either published or t o be published . There a re other matters in which t he investigations are not yet sufficientl y advanced t o enable documents t o be released but which are on the \VOrking programme of the Commission ; t hey are as follows : I) Definition of the production capacity of spot welding machines and an attempt t o charact erize them by the number of spot welds made per hour under certain conditions. z) The p reparation of a report on research work on resist ance welding undertaken by the different countries, in order t o avoid as far as possible duplication of effort and loss of time. 3) The est ablishment of a bibliographical report on the welding of dissimilar met als. 4) The constitution of a Sub-Commission E « Productivity n dealing especially, at least at first , with the p roblems of resistance welding in mot or manufacture, and comprising representatives of the following countries : Germany, F rance, Italy, United Kingdom. This Sub-Commission will h ave the task of preparing a study on the means t o be used t o improve productivity in this industry. * * * During the last t en years, Commission III has clone useful work. It is difficult t o get international work under way, and progress necessitat es the dedicat ed and continuous collaboration of the delegat es and experts from each count ry wit hin the Commission and its Sub-Commissions. In view of the work which has been accomplished, a nd of its increasing impo rtance, future activity can, howeve r, be regarded with much optimism. 4. FUTURE PROGRAMME.

(r) Report published in Belgium in the R evue H . F. Electi-icite - Coitrants fa-ibles , vol. II, n ° 3, r95 2 (55, rue Defacqz - Brussels). (z) Document III-58-56.