The Closed-loop Real-time Controlling of Short-circuiting Transfer in CO₂ Arc Welding

In this paper, an idea of closed-loop real-time controlling of short-circuiting transfer is proposed and is experimentally studied for decreasing the spatter in the short-circuiting transfer process of the CO₂ welding.At the two moments when spatter is most easily produced-short circuiting between droplet and welding puddle and the liquid bridge exploding-welding current is reduced in time by the method of high power element switching the resistance which is in settes connection with the welding circuit. At the former moment, a low current is held until the droplet fully contacts with the welding pool. At the later moment, another low current is held until the droplet transfer ends, and the large spatter caused by the incipient short circuiting and the small spatter caused by electrical explosion can be obviously reduced.The closedloop real-time control of short-circuiting transfer process of CO₂ welding is realized.