ARC START CONTROL METHOD

摘要

At the time of starting a consumable electrode arc welding operation, a welding wire is made to contact a parent metal, and is then retracted and fed with an initial current. As a result, an initial arc is generated, and the retraction of the welding wire is continued for an initial arc pull-up period (Ti) while the initial arc being kept. Then, a shift is made from the initial arc to a steady arc. After the lapse of the initial arc pull-up period (Ti), a molten pool forming period (Tp) is preset. During this molten pool forming period, the molten pool forming current higher than the initial current is fed while the initial arc being kept, and the welding wire is moved forward to the parent metal. During the molten pool forming period, a molten pool is so formed by the initial arc that droplets are not moved from the welding wire, and that the welding wire is kept away from contact with the parent metal. According to the control method thus far described, the shift is made to the steady arc state after the molten pool was formed, thereby to suppress the occurrence of a sputtering, as might otherwise accompany the transfer of the droplets to the parent metal.