According to different uses, seamless steel pipes can be divided into thick-walled seamless steel pipes and thin-walled seamless steel pipes. Seamless steel pipes are widely used.
General-purpose seamless steel pipes are rolled from ordinary carbon structural steel, low-alloy structural steel or alloy structural steel according to their materials. For example, seamless pipes made of low carbon steel such as No. 10 and No. 20 are mainly used as pipelines for steam, coal gas, liquefied gas, natural gas, various petroleum products and various other gases or liquids; medium carbon steel such as 45 and 40cr The manufactured seamless pipes are mainly used to manufacture various machine fittings and pipe fittings.
General-purpose seamless steel pipes are also supplied according to chemical composition and mechanical properties, and supplied according to hydrostatic test. For seamless steel pipes subjected to fluid pressure, the hydrostatic test shall be qualified.
Special-purpose seamless pipes are used in boilers, geological exploration, bearings, acid resistance, etc. Such as petroleum geological drilling pipes, cracking pipes for petrochemical industry, boiler pipes, bearing pipes, and high-precision structural steel pipes for automobiles, tractors, and aviation.
