Mash seam welding process and mash seam welding apparatus

摘要

Mash seam welding process and apparatus, wherein two plate- like workpieces having different thickness values are fed and guided by a guiding device such that a length W.sub.H of contact of the thick plate- like workpiece with one of two roller electrodes is smaller than a length W.sub.M of contact of the thin plate-like workpiece with the other roller electrode. In this arrangement, the amount of mashing of the thick plate- like workpiece by the roller electrode is made larger than that of the thin plate-like workpiece by the other roller electrode, so that an interface of the two plate-like workpieces is positioned intermediate between the pair of roller electrodes, whereby a weld nugget formed intermediate between the roller electrodes extends across the interface, permitting the weld to have a sufficient strength owing to a nugget ratio, which is a ratio of a width dimension W.sub.N of the weld nugget in the direction of the interface to a width dimension W.sub. G of the interface.