The straight seam steel pipe is a steel pipe with the longitudinal parallel of the weld and the steel pipe. It is usually divided into public electric welding steel pipes, welding thin wall pipes, transformer cooling oil pipes, etc. The production process of straight welding pipes is simple, high production efficiency, low cost, and rapid development.
The straight seam steel pipe can be divided into high -frequency straight steel pipes and buried arc welding straight seam steel pipes according to the production process. Buried arc welding straight steel pipes are divided into UOE, RBE, JCOE steel pipes, etc. according to their different molding methods. Here are the production processes of the most common high -frequency straight seam steel pipes and buried arc welding straight seam steel pipes.
1. Detective: After the steel plates used to create large -caliber buried arc welding straight steel pipes into the production line, the full board ultrasonic inspection is performed first; the production can be performed after confirming the qualification.
2. Milling edge: According to the requirements of the pipe diameter, double -sided milling on the two edges of the steel plate by the milling machine can achieve the required plate width, parallel parallelity, and horn shape.
3. Pre -bending edge: Use the pre -bending machine to pre -bending on the edge of the board, so that the edge of the board has a curved curvature.
4. For molding: First of all, half of the steel plate after the pre -curved steel plate was stamped multiple times on the JCO molding machine, pressed it into a "J" shape, and then the other half of the steel plate was also bent, pressed into a "C" shape, and finally formed an opening opening. "O" shape
5. Pre -welding: Make the forming straight seam welding steel pipes sew and use gas protection welding (MAG) for continuous welding;
6. Internal welding: Use the columns to bury the arc welding (up to four wires) on the inside of the straight steel pipes;
7. External welding: Welded on the outside of the stitched arc welded steel pipe with the use column -wire buried arc welding;
8. Ultrasonic inspection Ⅰ: 100%inspection of the latch welds and welds in the straight seam welded steel pipes and welds;
9. X -ray examination Ⅰ: 100%X -ray industrial TV inspection of welded seams internal and external welds is performed, and an image processing system is used to ensure the sensitivity of the detection;
10. Expansion: The full length of the burial arc welding straight seam steel pipe is expanded to improve the size and accuracy of the steel pipe, and improve the distribution status of the stress in the steel pipe;
11. Water pressure test: The steel pipe after the diameter expanded on the hydraulic test machine is inspected to ensure the test pressure of the steel pipe to meet the standard requirements. The machine has an automatic recording and storage function;
12. Inverted edges: The pipe ending of the steel pipe after the inspection is passed to meet the required pipe end slope size;
13. Ultrasonic test II: The ultrasonic inspection is performed again to check the defects that the straight welding steel pipes may produce after the diameter and water pressure;
14.X Radio Examination II: Perform X -ray industrial TV inspections and tube welds for steel pipes after the diameter and hydraulic test;
15. Tube end magnetic powder test: conduct this inspection to discover the tube -end defects;
16. Corruption: The qualified steel pipes are processed according to user requirements.
