Thick-walled seamless steel pipe

The production process of thick-walled seamless steel pipe:

1. Round tube blank→heating→piercing→three-roll skew rolling, continuous rolling or extrusion→tube removal→sizing (or diameter reduction)→cooling→straightening.

2. Cold drawn (rolled) seamless steel pipe:
Round tube blank→heating→piercing→heading→annealing→pickling→oiling (copper plating)→multi-pass cold drawing (cold rolling)→blank tube heat treatment (such as quenching and tempering, normalizing, annealing, etc.)→blank tube Straightening → finishing.

3. Manufacturing process of thermally expanded seamless steel pipe:
Round tube billet→heating→piercing-heading–annealing–pickling–oiling–multi-pass cold drawing (cold rolling)–blank straightening–finishing.

4. The production process of hot rolled seamless steel pipe is the same as that of hot expansion, except that the hollow capillary tube is smaller.

5. The top method inserts the pipe into the mandrel, and when the predetermined length is reached, the mandrel is removed.

6. The wire drawing method is to draw the metal wire into filaments through the die.

7. The extrusion method is to move the metal bar forward under the extrusion of the extruder.

8. There are three commonly used bending methods:
One method is hydraulic bending; the other is mechanical bending; the third is flame bending.

9. Straightening machine The straightening machine is mainly used to check and adjust the straightness and verticality of super-long section steel and produce seamless steel pipes of various angles.

10. Chamfering Curl the steel plate along the outer circumference into a circular ring shell.

11. Slotting Slotting is to curl the steel plate along the outer circumference into a circular ring shell.

12. Rolling Use a tapered core to wrap the edge of the board into a curved surface. Rolling should ensure that the edges are neat and not deformed.

13. Trimming Use special tools to cut the flanging and cut off the iron oxide scale.

14. Polishing Perform bright solution treatment on the entire flow line of the large-diameter spiral welded pipe.

15. Flaw detection Carry out ultrasonic flaw detection one by one according to the GB7735 standard.

16. Spray mark Spray mark is the mark of the serial number, specification and production batch number sprayed with paint.