During cold drawing, only cold drawing rate or cold drawing stress control is called single control; during cold drawing, cold drawing rate and cold drawing stress are applied at the same time, which is called double control.

The quality of the inner hole finish of the cold drawn seamless tubing will bring many troubles to customers, which will not only affect the customer's yield, but also affect the quality of the finished product. So what is the finish of the inner hole of the cold drawn seamless tubing?

Stainless seamless steel pipe is a relatively common material in production, and is widely used in industrial transportation pipelines such as petroleum, chemical industry, medical treatment, food, light industry, mechanical instrumentation, etc.,among them, the thick wall of stainless seamless steel pipe is not well cooled uniformly. How to deal with this problem?

The carbon in the cs seamless pipe is very easy to react with oxygen at high temperature, Fe0+C→Fe+C0, which reduces Fe0; the reduced Fe will be oxidized again, and then reduced again.

There are various reasons for the longitudinal crack of the welded pipe, but the fundamental reason is that the welded pipe after cold drawing has a high residual stress field.

In the actual production process, the black steel seamless pipe will be polished and its coating process will be carried out to improve the corrosion resistance of the steel pipe.