METHOD AND DEVICE FOR NARROW GAP WELDING

摘要

PURPOSE:To form stably a satisfactory penetration bead by connecting the cathode of a welding power source to a welding torch and the anode to objects to be welded and ejecting a shielding gas from shielding gas nozzles fitted externally to the welding torch and a control gas from a control nozzle provided behind the welding torch to the extended part behind a molten pool. CONSTITUTION:The cathode (-) of a welding power source in gas shielded welding of a single-I narrow gap is connected to a welding torch 40 and the anode (+) to objects 25 to be welded. A shielding gas is ejected from shielding gas nozzles 3, 4 fitted externally to the torch 40 and a control gas is ejected from a control gas nozzle 5 provided behind the torch 40 toward the extended part behind a molten pool 31. The molten pool 31 is thus pushed forward and is formed to a recessed surface shape.