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Introduce the production process of large diameter stainless steel pipe.

large diameter stainless steel pipeDue to its high ability to work under pressure, low friction resistance, cold resistance, corrosion resistance, convenient installation and maintenance and other advantages, it is more and more warmly welcomed by the manufacturing industries such as petrochemical industry, coal slurry transportation, steel structure engineering construction and so on.
 

The key production process of large diameter straight seam stainless steel welded pipe is as follows:

1. Plate detection: After the thick steel plate used to produce large-diameter submerged arc welded straight seam steel pipe enters the production line, the whole plate ultrasonic detection is first carried out;

2. Edge milling: According to the edge milling machine, both sides of the thick steel plate are cut to achieve the specified plate width, plate edge flatness and weld appearance;

3. Pre-bending edge: use the pre-bending machine to carry out the pre-bending of the edge of the plate, so that the edge of the plate has the required refractive index;

4. Forming: On the JCO forming machine, half of the pre-bent thick steel plate is first rolled into a "J" shape through several stepping motor stamping dies, and then the other half of the thick steel plate is bent like the same, rolled into a "C" shape, and finally an "O" shape with an open mouth is produced.

5. Pre-welding: make the formed straight seam welded steel pipe seam and select gas shielded welding (MAG) to carry out continuous electric welding;

6. Internal welding: longitudinal multi-wire submerged arc welding (up to four wires) is selected to carry out electric welding on the inner side of straight seam steel pipe;

7. External welding: longitudinal multi-wire submerged arc welding is selected to carry out electric welding on both sides of the longitudinal submerged arc welding steel pipe;

8. Ultrasonic inspection I: 100% inspection of the internal and external welding of the straight seam welded steel pipe and the butt weld on both sides of the welding;

9.X-ray inspection I: 100% X-ray industrial television inspection of internal and external welding is carried out, and image processing system software is selected to ensure the sensitivity of flaw detection;

10. Diameter expansion: to expand the total length of submerged arc welding straight seam steel pipe to improve the specification precision of steel pipe and improve the spread of thermal stress of steel pipe;

11. Pressure test: the expanded steel pipes are tested one by one on the hydraulic testing machine to ensure that the steel pipes achieve the experimental working pressure specified in the specification. The equipment has the functions of automatic preservation and storage;

12. chamfering: carry out pipe end production and processing of steel pipes that have reached the standard after testing, and achieve the specified pipe end weld specifications;

13. ultrasonic detection II: ultrasonic detection is carried out one by one again to check the defects that will be caused by the expansion and pressure of the straight seam welded steel pipe;

14.X-ray inspection II: X-ray industrial television shall be carried out to regularly inspect the pipe end welding film after the diameter expansion and pressure test of the steel pipe;

15. Pipe end magnetic particle inspection: carry out the inspection to find out the defects of pipe end;

16. Anti-corrosion and coating: The steel pipe after reaching the standard shall carry out anti-corrosion and coating according to the customer's regulations.

Introduce the production process of large diameter stainless steel pipe.

Large-diameter stainless steel pipes are increasingly warmly welcomed by petrochemical, coal slurry transportation, steel structure engineering construction and other manufacturing industries due to their advantages of high pressure working capacity, low friction resistance, cold resistance, corrosion resistance, and convenient installation and maintenance.

The key production process of large diameter straight seam stainless steel welded pipe is as follows:

1. Plate detection: After the thick steel plate used to produce large-diameter submerged arc welded straight seam steel pipe enters the production line, the whole plate ultrasonic detection is first carried out;

2. Edge milling: According to the edge milling machine, both sides of the thick steel plate are cut to achieve the specified plate width, plate edge flatness and weld appearance;

3. Pre-bending edge: use the pre-bending machine to carry out the pre-bending of the edge of the plate, so that the edge of the plate has the required refractive index;

4. Forming: On the JCO forming machine, half of the pre-bent thick steel plate is first rolled into a "J" shape through several stepping motor stamping dies, and then the other half of the thick steel plate is bent like the same, rolled into a "C" shape, and finally an "O" shape with an open mouth is produced.

5. Pre-welding: make the formed straight seam welded steel pipe seam and select gas shielded welding (MAG) to carry out continuous electric welding;

6. Internal welding: longitudinal multi-wire submerged arc welding (up to four wires) is selected to carry out electric welding on the inner side of straight seam steel pipe;

7. External welding: longitudinal multi-wire submerged arc welding is selected to carry out electric welding on both sides of the longitudinal submerged arc welding steel pipe;

8. Ultrasonic inspection I: 100% inspection of the internal and external welding of the straight seam welded steel pipe and the butt weld on both sides of the welding;

9.X-ray inspection I: 100% X-ray industrial television inspection of internal and external welding is carried out, and image processing system software is selected to ensure the sensitivity of flaw detection;

10. Diameter expansion: to expand the total length of submerged arc welding straight seam steel pipe to improve the specification precision of steel pipe and improve the spread of thermal stress of steel pipe;

11. Pressure test: the expanded steel pipes are tested one by one on the hydraulic testing machine to ensure that the steel pipes achieve the experimental working pressure specified in the specification. The equipment has the functions of automatic preservation and storage;

12. chamfering: carry out pipe end production and processing of steel pipes that have reached the standard after testing, and achieve the specified pipe end weld specifications;

13. ultrasonic detection II: ultrasonic detection is carried out one by one again to check the defects that will be caused by the expansion and pressure of the straight seam welded steel pipe;

14.X-ray inspection II: X-ray industrial television shall be carried out to regularly inspect the pipe end welding film after the diameter expansion and pressure test of the steel pipe;

15. Pipe end magnetic particle inspection: carry out the inspection to find out the defects of pipe end;

16. Anti-corrosion and coating: The steel pipe after reaching the standard shall carry out anti-corrosion and coating according to the customer's regulations.