| 摘要 |
PURPOSE:To form an excellent welded joint stably in a resistance seam welding method, by using a pulsating current which contains a DC and AC component and whose instantaneous value never reaches zero as a welding current in use. CONSTITUTION:Materials 2a and 2b to be welded are stacked, pressed from above and below by a couple of rotating electrodes 1a and 1b, and fed with electricity while moving, thus performing resistance seam welding between the materials 2a and 2b by the resistance heat of the current. In this case, an pulsating current consisting of a DC and an AC component is used for the welding; its minimum instantaneous value is higher than 0 because of the DC part and a high temperature part and a low temperature part are repeated by generated adequately because of the AC component, thereby forming an excellent welded joint part free of defection of welding due to a deficiency in current and burrs due to an excess of current. This current is fed from a single-phase AC rectifying circuit equipped with inductive reactance and a DC power source, or a three- phase rectifying circuit capable of current control. |
