According to different applications, seamless steel pipes include thick-walled seamless steel pipes and thin-walled seamless steel pipes. Seamless steel pipes are widely used.
1. General purpose seamless steel pipes are rolled from ordinary carbon structural steel, low alloy structural steel or alloy structural steel according to the material. 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; The manufactured seamless pipes such as 45, 40Cr and other medium carbon steels are mainly used to manufacture various machine fittings and pipe fittings.
2. Seamless steel pipes for general purposes are also supplied by chemical composition and mechanical properties, and by hydraulic test. The seamless steel pipe subjected to fluid pressure shall ensure that the hydraulic test is qualified.
3. Special purpose seamless tubes are used in boilers, geological exploration, bearings, acid resistance, etc., such as petroleum geological drilling pipes, cracking pipes for petrochemicals, boiler pipes, bearing pipes, and high-precision structural steel pipes for automobiles, tractors, and aviation.
Structural seamless steel pipes are mainly used for general structures and mechanical structures. Its representative material (brand): carbon steel 20, 45 steel; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo, etc.
The seamless steel pipe for conveying fluid is mainly used for conveying fluid pipeline in engineering and large scale equipment. The representative material (grade) is 20, Q345, etc.
Seamless steel pipes for low and medium pressure boilers are mainly used for pipelines for conveying low and medium pressure fluids in industrial boilers and domestic boilers. The representative material is 10, 20 steel.
Seamless steel pipes for high pressure boilers are mainly used for high temperature and high pressure transport fluid headers and pipes on boilers in power plants and nuclear power plants. The representative materials are 20G, 12Cr1MoVG, 15CrMoG, etc.
Carbon steel and carbon manganese steel seamless steel pipes for ships are mainly used for I and II pressure-resistant pipes for ship boilers and superheaters. The representative material is 360, 410, 460 steel grades, etc.Seamless steel pipes for high-pressure fertilizer equipment are mainly used for high-temperature and high-pressure fluid pipelines on fertilizer equipment. The representative materials are 20, 16Mn, 12CrMo, 12Cr2Mo, etc.
Seamless steel pipes for petroleum cracking are mainly used in boilers, heat exchangers and their fluid pipelines in petroleum smelters. Its representative materials are 20, 12CrMo, 1Cr5Mo, 1Cr19Ni11Nb, etc.
Seamless steel pipes for gas cylinders are mainly used to make various gas and hydraulic cylinders. Its representative materials are 37Mn, 34Mn2V, 35CrMo and so on.
Hot rolled seamless steel pipes for hydraulic props are mainly used to make hydraulic supports, cylinders and columns in coal mines, as well as other hydraulic cylinders and columns. Its representative materials are 20, 45, 27SiMn, etc.
High pressure seamless steel pipe for diesel engine, mainly used for high pressure oil pipe of diesel engine injection system. The steel pipe is generally cold drawn pipe, and its representative material is 20A.
Cold-drawn or cold-rolled precision seamless steel pipes are mainly used for steel pipes for mechanical structures and carbon pressing equipment that require high dimensional accuracy and good surface finish. It represents material 20, 45 steel and so on.
Cold-drawn seamless steel pipe special-shaped steel pipe is mainly used to make various structural parts and parts, and its material is high-quality carbon structural steel and low-alloy structural steel.
Precision inner diameter seamless steel pipes for hydraulic and pneumatic cylinders are mainly used to make cold drawn or cold rolled seamless steel pipes with precise inner diameters for hydraulic and pneumatic cylinders. Its representative material is 20, 45 steel and so on.
Stainless steel seamless steel pipes for boilers and heat exchangers are mainly used for boilers, superheaters, heat exchangers, condensers, catalytic tubes, etc. in chemical enterprises. High temperature, high pressure and corrosion resistant steel pipes. Its representative materials are 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti and so on.
Structural stainless steel seamless pipes are mainly used for general structure (hotel, restaurant decoration) and mechanical structure of chemical enterprises with resistance to atmoSPHEre, acid corrosion and a certain strength of steel pipe. Its representative materials are 0-3Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti, etc.
Stainless steel seamless steel pipe for fluid transportation, mainly used for pipelines conveying corrosive media. The representative materials are 0Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr17Ni12Mo2, 0Cr18Ni12Mo2Ti, etc.
Seamless steel pipes for automobile axle casings are mainly used to make high-quality carbon structural steel and alloy structural steel hot-rolled seamless pipes for automobile axle casings and axle casings of drive axles. Its representative materials are 45, 45Mn2, 40Cr, 20CrNi3A, etc.