The equipment consists of a host head, a traction bed body, and a feeding platform. At the same time as the steel bars are joined, the welding machine starts arc welding. This equipment adopts submerged arc automatic welding, automatic flux recovery, uniform, continuous and beautiful welds, strong penetration, one-time forming, high welding efficiency, speed of 2-3 meters/minute, three times that of gas shielded welding.