1. Board test: used to make large diameter submerged arc welded steel pipe into the production line, the first full-board ultrasonic inspection;
2. Milling: through the milling machine on both sides of the steel plate on both sides of the milling, so that the board to reach the demand, board parallelism and groove shape;
3. Pre-bending: the use of pre-bending machine for the edge of the pre-bend, so that the board has a curvature in line with demand;
4. Forming: In the JCO forming machine on the first half of the steel after the pre-bending through the repeated step into the stamping, pressed into the "J" shape, and then the other half of the same twists and turns, pressed into "C" shape, and ultimately constitute the opening " O "shape;
5. Pre-welding: the forming of the straight seam welded steel pipe joints and the use of gas maintenance welding (MAG) for welding;
6. Internal welding: the use of vertical multi-wire submerged arc welding (up to five wire) in the straight seam steel pipe inside the welding;
7. External welding: the use of vertical multi-wire submerged arc welding in the straight seam submerged arc welded pipe outside the welding;
8. Ultrasonic inspection Ⅰ: Longitudinal seam welded pipe on both sides of the weld and weld on both sides of the base metal 100% view;
9. X-ray inspection Ⅰ: 100% of the surface of the weld X-ray industrial TV view, the use of image processing system to ensure the sensitivity of testing;
10. Enlargement: the full length of the submerged arc welded straight pipe is expanded to improve the scale accuracy of the steel pipe and improve the distribution of the stress in the steel pipe.
11. Water pressure test: in the hydraulic press on the expansion of the steel pipe after the root inspection to ensure that the steel pipe to meet the specifications of the experimental pressure, the machine has an automatic recording and storage function;
12. Chamfering: the pipe will be qualified after the end of the pipe processing, to reach the needs of the pipe end groove scale;
13. Ultrasonic inspection Ⅱ: again by root ultrasonic inspection to see the straight seam welded steel pipe in the expansion, water pressure can occur after the shortcomings;
14. X-ray view Ⅱ: the expansion and water pressure after the test of the steel pipe X-ray industrial TV viewing and pipe-side welding film;
15. Tube-side magnetic powder inspection: to carry out this view to find the pipe terminal shortcomings;
16. Anti-corrosion and coating: qualified steel pipe according to user needs for corrosion and coating.
