METHOD FOR DETECTION OF UNDERCUT DEFECT, DETECTION DEVICE FOR UNDERCUT DEFECT, AND FILLET ARC-WELDING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method by which on-line detection of an undercut defect can be performed in arc-welding.SOLUTION: A method for detecting an undercut defect during welding when a fillet arc-welding is performed while weaving a weld torch, in which a weld part circumference immediately after coagulation of a weld zone circumference for arc-welding of a fillet is photographed by a camera, and a reflectance of ark light is monitored. When a reflectance of ark light, which is observed and has a brightness higher than that of a portion corresponding to an inversion position of weaving, is detected, it is determined that an undercut defect is generated.SELECTED DRAWING: Figure 2