Abstract
In this paper we describe an application of arc sound for the detection of welding process. Arc sound has a good competence for the useful source of the information with high level of SPL and good S/N. The hole and step on the base metal, change in arc length, change in groove width, interruption of shielding gas, humping bead formation and burn-through were detected by the arc sound. And the value of its application was confirmed.
