GB772398A - Welding by high-frequency induction heating - Google Patents

Abstract

772,398. Welding by pressure. MAGNETIC HEATING CORPORATION. Aug. 5, 1955 [Sept. 16, 1954], No. 22635/55. Class 83 (4). [Also in Group XI] In welding two opposed edge portions of metal members, e.g. the edge portions 13a, 13b of a steel tube 10, which are longitudinally advancing with a V-shaped gap therebetween into abutting relation at a weld point w, the metal along the edges is heated by highfrequency induction, the current being maintained in a path adjacent each edge from a point adjacent the edge on one surface of the member, along the surface, down across the edge to the other surface near the edge, back along the other surface adjacent the edge to a point corresponding to the starting point and finally across the edge to the starting point by conductors 14, 15 carrying high frequency current and extending parallel to and closely spaced from the paths. The conductors are of watercooled copper tubing formed into two series connected single turn coils 14, 15 and the frequency employed may be under 10,000 cycles per second, but is preferably between 300,000-400,000 cycles per second. Rollers 11, 12 press the edges together at the weld point. Multi-turn coils may be used instead of single turn coils.