US Patent 8203100 Pulse arc welding method

A pulse arc welding method is provided for performing welding by causing welding current to flow through a welding wire and a base metal via a power supply tip. The welding current has a pulse cycle made up of a first peak time, a second peak time and a base time. A first peak current is applied during the first peak time, a second peak current, smaller than the first peak current, is applied during the second peak time, and a base current is applied during the base time. When a tip-base distance between an end of the power supply tip and the base metal is smaller or greater than a reference value, the first peak current is increased or decreased in accordance with the difference between the reference value and the tip-base distance.