(1) the raw material Strip, welding wire, flux. In front of the input must pass a strict physical and chemical examination.
(2) the Strip head and tail docking, single-wire or two-wire submerged arc welding, in rolled steel by submerged arc welding-welding.
(3) before molding Strip after leveling, edge cutting, Beveling, surface cleaning, transportation and curved edges.
(4) controlled by electric contact pressure gauge pressure of cylinders under pressure on both sides of the conveyor to ensure the smooth transportation of the Strip.
(5) using the external or internal roll forming.
(6) use weld leakage control device to ensure the weld gap to meet the requirements pipe diameter, unfitness and weld gap were strictly controlled.
(7) within and outside welding using United States Lincoln Electric welding machine for single or twin-wire submerged arc welding, welding so as to secure a stable specification.
(8) finished welding the weld passes through the automatic on-line ultrasonic instrument hurt checks to ensure 100% coverage of nondestructive testing of spiral weld. If there are defects, automatic alarm and sprayed the tag, and accordingly adjust the parameters of production workers, eliminate the defects in a timely manner.
(9) air plasma cutting machine cut the pipe into the single.