GAS SHIELDED ARC WELDING METHOD FOR GALVANIZED STEEL SHEET, WELDING MACHINE THEREFOR AND GALVANIZED STEEL SHEET PRODUCT WELDING BY THE WELDING METHOD AND THE MACHINE

摘要

PURPOSE: To perform welding of galvanized steel sheet while maintaining satisfactory welding workability by performing pulse MAG welding and short circuiting transfer welding alternately. ;CONSTITUTION: In consumable electrode welding, welding is performed with gas containing argon gas and gaseous carbon dioxide as shielding gas. Pulse MAG welding A superimposed with a pulse current and short circuting transfer welding B are then performed alternately. Oxygen gas of 2-7% is mixed into the shielding gas to perform welding. The gas shielded arc welding machine is provided with a short-circuit current setting device and a pulse current setting device, the output of each setting device is inputted to a changeover switch and output signals of the short-circuit current setting device and the pulse current setting device are outputted alternately according to an output signal from a frequency setting device. Consequently, the welding quality is improved, the decrease of bead external appearance is surpressed and lowering of working efficiency of spatter removing work, readjustment of a weld zone, etc., can be solved.;COPYRIGHT: (C)1995,JPO