Spiral steel pipes are made from steel coil sheets as raw materials, formed at room temperature, and welded using the automatic double-wire double-sided submerged arc welding process.(1) The raw materials include steel coils, welding wires, and welding flux. All of them must undergo strict physical and chemical inspections before being put into use.(2) The steel strips are butt-welded at both ends, and single-wire or double-wire submerged arc welding is used. After rolling into steel pipes, automatic submerged arc welding is used for supplementary welding.(3) Before forming, the steel strips undergo straightening, trimming, beveling, surface cleaning, and pre-bending treatment.(4) The pressure of the conveyor is controlled by an electric contact pressure gauge to ensure the smooth transportation of the steel strips.(5) External or internal roller forming is adopted.(6) A weld gap control device is used to ensure that the weld gap meets the welding requirements.