CS seamless pipe is a kind of long steel. The steel pipe has a hollow section and is widely used as a pipeline for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and certain solid materials. Compared with solid steel such as round steel, steel pipe has the same flexural and torsional strength, and is lighter in weight. It is an economical section steel and is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, bicycle racks and steel scaffolding used in building construction, etc.