Seamless Steel Pipes are perforated by the whole round steel, and the steel pipes without welds on the surface are called seamless steel pipes. According to the production method, seamless steel pipe can be divided into hot-rolled seamless steel pipe, cold-rolled seamless steel pipe, cold drawn seamless steel pipe, extruded seamless steel pipe, pipe jacking, etc. According to the cross-section shape, seamless steel pipes are divided into circular and special-shaped pipes. Special-shaped pipes have many complex shapes, such as square, oval, triangle, hexagon, melon seed, star and winged pipes. The maximum diameter is 900mm and the minimum diameter is 4mm. According to different uses, there are thick wall seamless steel pipe and thin wall seamless steel pipe. Seamless steel pipes are mainly used as drilling pipes for petroleum geology, cracking pipes for petrochemical industry, boiler pipes, bearing pipes and high-precision structural steel pipes for automobiles, tractors and aviation.
