Seamless steel pipes are categorized into thick-walled and thin-walled types based on their intended use. They have a wide range of applications.
1. General-purpose seamless steel pipes are rolled from ordinary carbon structural steel, low-alloy structural steel, or alloy structural steel, depending on their material. For example, seamless steel pipes made from low-carbon steels such as No. 10 and No. 20 are mainly used for transporting steam, coal gas, liquefied petroleum gas, natural gas, various petroleum products, and other gases or liquids. Seamless steel pipes made from medium-carbon steels such as 45 and 40Cr are mainly used to manufacture various machine parts and pipe fittings.
2. General-purpose seamless steel pipes are also supplied based on chemical composition and mechanical properties, or on hydrostatic testing. Seamless steel pipes subjected to fluid pressure must pass the hydrostatic test.
3. Special-purpose seamless steel pipes are used in boilers, geological exploration, bearings, acid resistance, etc. Examples of seamless steel pipes include: oil and gas drilling pipes, cracking pipes for petrochemicals, boiler tubes, bearing tubes, and high-precision structural steel pipes for automobiles, tractors, and aviation.
Structural seamless steel pipes are mainly used in general structures and mechanical structures. Representative materials (grades) include: carbon steel 20 and 45; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, and 42CrMo.
Seamless steel pipes for fluid transportation are mainly used in engineering and large equipment for transporting fluids. Representative materials (grades) include 20 and Q345.
Seamless steel pipes for low and medium pressure boilers are mainly used in industrial and domestic boilers for transporting low and medium pressure fluids. Representative materials are 10 and 20 steel.
Seamless steel pipes for high pressure boilers are mainly used in high-temperature and high-pressure fluid transport headers and pipelines in power plants and nuclear power plant boilers. Representative materials include 20G, 12Cr1MoVG, and 15CrMoG.
Seamless carbon steel and carbon-manganese steel pipes for shipbuilding are mainly used for Class I and II pressure-resistant pipes in ship boilers and superheaters. Representative materials include steel grades 360, 410, and 460.
Seamless steel pipes for high-pressure fertilizer equipment are mainly used for pipelines transporting high-temperature and high-pressure fluids in fertilizer equipment. Representative materials include 20, 16Mn, 12CrMo, and 12Cr2Mo.
Seamless steel pipes for petroleum cracking are mainly used in boilers, heat exchangers, and fluid transport pipelines in petroleum refineries. Representative materials include 20, 12CrMo, 1Cr5Mo, and 1Cr19Ni11Nb.
Seamless steel pipes for gas cylinders are mainly used to manufacture various gas and hydraulic cylinders. Representative materials include 37Mn, 34Mn2V, and 35CrMo.
Hot-rolled seamless steel pipes for hydraulic supports are mainly used to manufacture hydraulic supports, cylinders, and columns for coal mines, as well as other hydraulic cylinders and columns. Representative materials include 20, 45, and 27SiMn.
High-pressure seamless steel pipes for diesel engines are mainly used for high-pressure fuel lines in diesel engine injection systems. These pipes are generally cold-drawn, with 20A as a representative material.
Cold-drawn or cold-rolled precision seamless steel pipes are mainly used in mechanical structures and pressure equipment, requiring high dimensional accuracy and a smooth surface finish. Representative materials include 20 and 45 steel.
Cold-drawn seamless steel pipes and shaped steel pipes are mainly used to manufacture various structural components and parts. They are made of 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 manufacture cold-drawn or cold-rolled seamless steel pipes with precise inner diameter dimensions for hydraulic and pneumatic cylinders. Representative materials include 20 and 45 steel.
Stainless steel seamless pipes for boilers and heat exchangers are mainly used in boilers, superheaters, heat exchangers, condensers, catalytic converters, etc., in chemical plants. High-temperature, high-pressure, and corrosion-resistant steel pipes are used. Representative materials include 0Cr18Ni9, 1Cr18Ni9Ti, and 0Cr18Ni12Mo2Ti.
Structural stainless steel seamless pipes are mainly used for general structures (hotel and restaurant decoration) and mechanical structures in chemical enterprises. They are resistant to atmospheric and acid corrosion and possess a certain strength. Representative materials include 0-3Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, and 0Cr18Ni12Mo2Ti.
Fluid transport stainless steel seamless pipes are mainly used for pipelines transporting corrosive media. Representative materials include 0Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr17Ni12Mo2, and 0Cr18Ni12Mo2Ti.
Seamless steel pipes for automobile axle sleeves are high-quality carbon structural steel and alloy structural steel hot-rolled seamless steel pipes mainly used for manufacturing automobile axle sleeves and drive axle housings. Its representative materials include 45, 45Mn2, 40Cr, and 20CrNi3A.
Post time: Apr-30-2026