PLASMA ARC WELDING METHOD AND PLASMA ARC WELDING DEVICE

摘要

Provided is a plasma arc welding method in which while forming a keyhole weld on the welding part of a welding workpiece using a plasma arc, the welding part is continuously welded. While using pulse current for a welding current, the pulse frequency of the pulse current is controlled so as to be a frequency that is synchronized with a weld pool (P) and thereby welding is performed. With this configuration, vibration of the weld pool during keyhole welding can be controlled so as to synchronize with the pulse frequency of the pulse current and as a result when performing plasma arc keyhole welding a stable penetration bead without hanging or irregularity and of a constant height can be reliably obtained.