ERW steel pipe

The production methods of seamless steel pipes can be roughly divided into oblique rolling method (Menesmann method) and extrusion method. The oblique rolling method (Menesmann method) is to first pierce the tube blank with oblique rolling rolls, and then extend it with a rolling mill. This method has a fast production speed, but requires high machinability of the pipe blank, and is mainly suitable for producing carbon steel and low alloy steel pipes. The extrusion method is to use a piercing machine to pierce the pipe blank or steel ingot, and then use an extrusion machine to extrude it into a steel pipe. This method is less efficient than the oblique rolling method and is suitable for producing high-strength alloy steel pipes. Both the oblique rolling method and the extrusion method must first heat the billet or ingot, and the steel pipe produced is called hot-rolled pipe. Steel pipes produced by hot working methods can sometimes be further cold worked as needed. There are two methods for cold working: one is the cold drawing method, which involves pulling steel pipes through a drawing die to gradually thin and elongate them; Another method is the cold rolling method, which applies the hot rolling machine invented by the Menesmann brothers to cold working. The cold processing of seamless steel pipes can improve the dimensional accuracy and processing smoothness of the pipes, and improve the mechanical properties of the materials.