METHOD FOR NARROW-GROOVE GAS-SHIELDED ARC WELDING

摘要

In this method that is for gas-shielded arc welding and that joins thick steel members having a plate thickness of at least 22 mm by means of narrow-groove multilayer welding with a bottom groove angle of no greater than 10° and a bottom groove gap of 7-15 mm inclusive, there are at least two root passes, each pass being divided among both sides of the bottom groove gap, and furthermore, by means of controlling the supply angle of welding wire supplied from an electricity supply tip at the tip of a welding torch to the range of 5-15° inclusive with respect to a normal line, the melting depth at the bottom of the thick steel members is at least 1.5 mm.