GB691373A - Improvements in and relating to processes for electric arc welding and to apparatus for carrying out such processes - Google Patents

Abstract

691,373. Uniting by fusion. GENERAL ELECTRIC CO., Ltd., and DONELAN, J. A. April 27, 1951 [April 28, 1950], No. 10517/50. Class 83 (iv). In a process of electric arc welding in which the arc is shielded by a stream of inert gas, a number of electrodes are connected to an alternating current supply, the currents in the electrodes being out of phase with each other. A pair of electrodes 10, 11, Fig. 1, in a shield 17 supplied with argon gas through a pipe 20, may be connected to a two-phase supply from a Scott-connected transformer 25, 27, the work 22 being connected to a common return 28. The phase relationship between the currents in the electrodes is 90 degrees so that there is always a potential between one of the electrodes and the work. The electrodes 10, 11 are adjustably mounted in sleeves 12, 14 which may be split at the lower end to provide a grip and are carried in a block 15 of insulating material. A body 16 attached to a handle or other supporting means carries the block 15 and the shield 17. In an alternative arrangement three electrodes are connected to a threephase supply. Sufficient weld metal may be provided by forming flanged or thickened edges on the work at the weld or by supplying weld metal from a filler rod.