Introduction to the production of thick-walled spiral pipe

Steel pipe with the ratio of outer diameter and wall thickness less than 20 is called thick-walled spiral pipe. Mainly used as petroleum geological drilling pipe, petrochemical cracking pipe, boiler pipe, bearing pipe and high precision structural pipe for automobile, tractor, aviation and so on.

The first thing to control the production of thick-walled spiral pipe is to improve the plastic toughness of the steel pipe, improve the cleanliness of the steel, reduce harmful inclusions and improve the overall quality of the steel pipe. A reasonable cooling system is used in the production process to avoid internal cracks and improve the quality of the steel pipe from various aspects.

Spiral pipe production process requires more procedures, the last step is to reduce the roll speed, roll speed is the key parameter of the perforating process, roll speed from low to high change process, there is a critical roll speed to begin to appear delamination. When the roll speed is low, the billet is easy to form a hole cavity; roll speed is high, the billet and 45# structural spiral steel pipe is easy to form layering defects. In order to eliminate the billet and 45 # structure spiral steel pipe delamination defects, the roll speed should be reduced to the beginning of the delamination of the critical roll speed below.

Spiral pipe in the production process of reasonable control of the heating temperature, through the determination of thermoplastic curve, select the optimal heating temperature. Billet heating should also pay attention to have enough holding time to reduce the deformation resistance and improve the 45# structural thick-walled spiral pipe plastic toughness.