1: Physical and chemical inspection of raw materials such as strip coils, welding wires, and fluxes.
2: The head and tail of the strip are butted, using single-wire or double-wire submerged arc welding, and automatic submerged arc welding is used after rolling into a steel pipe
2: Before forming, the strip is leveled, trimmed, planed, surface cleaned and conveyed, and pre-bending.
4: Use the electric contact pressure gauge to control the pressure of the cylinders on both sides of the conveyor to ensure the smooth conveying of the strip.
5: Use external control or internal control roll forming.
6: The welding seam gap control device is used to ensure that the welding seam gap meets the welding requirements, and the pipe diameter, the amount of misalignment, and the welding seam gap are strictly controlled.
7: Both internal welding and external welding use the American Lincoln welding machine for single-wire or double-wire submerged arc welding, to obtain stable welding quality.