The common seamless steel pipe standards in China are as follows:
1. Seamless steel pipe for structure (GBT8162-2008). Mainly used for general structure and mechanical structure. Its representative material (brand): carbon steel, 20, 45 steel; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo, etc.
2. Seamless steel pipes for conveying fluids (GBT8163-2008). It is mainly used for conveying fluid pipelines in engineering and large-scale equipment. The representative material (grade) is 20, Q345, etc.
3. Seamless steel pipes for low and medium pressure boilers (GB3087-2008) are used to manufacture various structures of low and medium pressure boiler superheated steam pipes, boiling water pipes and superheated steam pipes, large smoke pipes, small smoke pipes and arch bricks for locomotive boilers Hot-rolled and cold-drawn (rolled) seamless steel pipes of high-quality carbon structural steel for pipes. The representative material is 10, 20 steel.
4. High-pressure boiler seamless steel pipe (GB5310-2008) is a high-quality carbon steel, alloy steel and stainless heat-resistant steel seamless steel pipe used to manufacture the heating surface of water-tube boilers with high pressure and above. The representative materials are 20G, 12Cr1MoVG, 15CrMoG, etc.
5. Seamless steel pipe for high-pressure fertilizer equipment (GB6479-2000) is a high-quality carbon structural steel and alloy steel seamless steel pipe suitable for chemical equipment and pipelines with a working temperature of -40~400℃ and a working pressure of 10~30Ma. The representative materials are 20, 16Mn, 12CrMo, 12Cr2Mo, etc.
6. Seamless steel pipes for petroleum cracking (GB9948-2006). Mainly used in boilers, heat exchangers and their transmission fluid pipelines in petroleum smelters. Its representative materials are 20, 12CrMo, 1Cr5Mo, 1Cr19Ni11Nb, etc.
7. The steel pipe for geological drilling (YB235-70) is a steel pipe used by the geological department for core drilling. It can be divided into drill pipe, drill collar, core pipe, casing and sedimentation pipe according to the purpose.
8. Seamless steel pipe for diamond core drilling (GB3423-82) is a seamless steel pipe for drill pipe, core pipe and casing for diamond core drilling.
9. Oil drilling pipe (YB528-65) is a seamless steel pipe that is thickened internally or externally at both ends of oil drilling. The steel pipe is divided into two types: threading and non-threading. The threading pipe is connected with the joint, and the non-threading pipe is connected with the tool joint by the method of butt welding.
10. Carbon steel and carbon-manganese steel seamless steel pipes for ships (GB/T 5312-2009) are suitable for the manufacture of Class I pressure-bearing piping systems, Class II pressure-bearing piping systems for ships, carbon steel and carbon steel for boilers and superheaters Manganese steel seamless steel pipe. Seamless steel pipes for pressure-bearing piping systems are classified into three grades according to design pressure and design temperature. The working temperature of the seamless steel pipe wall for boilers and superheaters should not exceed 450℃.
11. Seamless steel pipes for automobile axle casings (GB3088-82) are high-quality carbon structural steel and alloy structural steel hot-rolled seamless pipes used for manufacturing automobile axle casings and axle casings of drive axles.
12. High-pressure oil pipe for diesel engine (GB3093-86) is a cold-drawn seamless steel pipe for manufacturing high-pressure pipe of diesel engine injection system.
13. Precision inner diameter seamless steel pipe for hydraulic and pneumatic cylinders (GB8713-88) is a cold-drawn or cold-rolled precision seamless steel pipe with precise inner diameter for manufacturing hydraulic and pneumatic cylinders.
14. Cold-drawn or cold-rolled precision seamless steel pipe (GB3639-83) is a cold-drawn or cold-rolled precision seamless steel pipe with high dimensional accuracy and good surface finish for mechanical structures and hydraulic equipment. The use of precision seamless steel pipes to manufacture mechanical structures or hydraulic equipment can greatly save machining hours, improve material utilization, and help improve product quality.
15. Structural stainless steel seamless steel pipe (GB/T14975-2002) is a hot-rolled ( Extrusion, expansion) and cold drawn (rolled) seamless steel pipes.
16. Stainless steel seamless steel pipe for fluid transportation (GB/T14976-2002) is a hot-rolled (extruded, expanded) and cold-drawn (rolled) seamless steel pipe made of stainless steel for fluid transportation.
17. Special-shaped seamless steel pipe is a general term for seamless steel pipes with other cross-sectional shapes other than round pipes. According to the shape and size of the steel pipe section, it can be divided into equal-wall thickness special-shaped seamless steel pipe (code D), unequal wall thickness special-shaped seamless steel pipe (code BD), variable diameter special-shaped seamless steel pipe (code BJ). Shaped seamless steel pipes are widely used in various structural parts, tools and mechanical parts. Compared with the round tube, the special-shaped tube generally has a larger moment of inertia and section modulus, and has a larger bending and torsion resistance, which can greatly reduce the structural weight and save steel.
18. Seamless steel pipes for gas cylinders (GB18248-2000). Mainly used to make various gas and hydraulic cylinders. Its representative materials are 37Mn, 34Mn2V, 35CrMo and so on.
