(1) Raw materials include steel coils, welding wire, and welding flux. All must undergo rigorous physical and chemical testing before use.

(2) Steel strip ends are joined using single or double wire submerged arc welding, followed by automatic submerged arc welding for reinforcement after rolling into steel pipes.

(3) Prior to forming, the steel strip is processed through leveling, trimming, edge trimming, surface cleaning conveyance, and pre-bending treatment.

(4) The electrical contact pressure gauge is used to control the pressure of the hydraulic cylinders on both sides of the conveyor, ensuring smooth and even steel strip transport.

(5) Utilize external or internal roll forming.

(6) Utilize a weld gap control device to ensure that the weld gap meets welding requirements, with strict control over pipe diameter, misalignment, and weld gap.

(7) Both internal and external welds are performed using Lincoln welding machines for single or double wire submerged arc welding, ensuring consistent welding quality.

(8) All weld seams are inspected by an online continuous ultrasonic flaw detector, ensuring full coverage of non-destructive testing for spiral welds. In case of any defects, an automatic alarm is triggered and marked, allowing production workers to adjust process parameters in real-time and promptly eliminate the defects.