(III)Arc Return Combustion Caused by Arc Instability

Many causes,including poor arc, arc instability, poor wire feeding and cleaning degree of work-piece surface, do not necessarily affect the performance of the contact tip itself. Welding faults are mainly related to welding power characteristics, wire quality, wire feeding effect, liners and contact tip structure design. When the conductive point in the welding wire and contact tip is often changed, the life is only half as stable as the conductive point.