GB Standard Classification and Use of Seamless Pipe

1. seamless pipe for structure (gb/t8162-2008) is a seamless pipe for general structure and mechanical structure.

2. seamless pipe for fluid transportation (gb/t8163-2008) is a general seamless pipe used to transport water, oil, gas and other fluids.

3. seamless pipes for low and medium pressure boilers (gb3087-2008) are used to manufacture superheated steam pipes, boiling water pipes for low and medium pressure boilers of various structures and superheated steam pipes for locomotive boilers, large smoke pipes, small smoke pipes and arch bricks high-quality carbon structural steel hot-rolled and cold-drawn (rolled) seamless pipes for pipes.

4. seamless pipes for high-pressure boilers (gb5310-2008) are high-quality carbon steel, alloy steel and stainless heat-resistant steel seamless pipes for the heating surface of water-tube boilers with high pressure and above.

5. high-pressure seamless pipe for fertilizer equipment (gb6479-2000) is a high-quality carbon structural steel and alloy steel seamless pipe suitable for chemical equipment and pipelines with a working temperature of -40 to 400 ℃ and a working pressure of 10 to 30 ma.

6. seamless pipes for petroleum cracking (gb9948-2006) are seamless pipes suitable for furnace tubes, heat exchangers and pipelines in petroleum refineries.

7. steel pipes for geological drilling (yb235-70) are steel pipes used for core drilling by geological departments. they can be divided into drill pipes, drill collars, core pipes, casing pipes and sedimentation pipes according to their purposes.

8. seamless pipe for diamond core drilling (gb3423-82) is a seamless pipe for drill pipe, core rod and casing for diamond core drilling.

9. petroleum drilling pipe (yb528-65) is a seamless pipe used for thickening inside or outside at both ends of oil drilling. there are two types of steel pipes: wire and non-wired. wired pipes are connected by joints, and non-wired pipes are connected with tool joints by butt welding.

10. carbon steel seamless pipes for ships (gb5312-85) are carbon steel seamless pipes used in the manufacture of class i pressure-resistant piping systems, class ii pressure-resistant piping systems, boilers and superheaters. the working temperature of the carbon steel seamless pipe wall does not exceed 450℃, and the working temperature of the alloy steel seamless pipe wall exceeds 450℃.

11. seamless pipes for automobile axle sleeves (gb3088-82) are high-quality carbon structural steel and alloy structural steel hot-rolled seamless pipes used in the manufacture of automobile axle sleeves and drive axle axle tubes.

12. high-pressure oil pipes for diesel engines (gb3093-86) are cold drawn seamless pipes used to manufacture high-pressure pipes for diesel engine injection systems.

13. precision inner diameter seamless pipes for hydraulic and pneumatic cylinders (gb8713-88) are cold-drawn or cold-rolled precision seamless pipes with precise inner diameters for the manufacture of hydraulic and pneumatic cylinders.

14. cold-drawn or cold-rolled precision seamless tubes (gb3639-83) are cold-drawn or cold-rolled precision seamless tubes for mechanical structures and hydraulic equipment with high dimensional accuracy and good surface finish. the use of precision seamless pipes to manufacture mechanical structures or hydraulic equipment can greatly save mechanical processing man-hours, improve material utilization, and at the same time help improve product quality.

15. structural stainless steel seamless pipe (gb/t14975-2002) is a hot-rolled stainless steel made of corrosion-resistant pipes and structural parts and parts widely used in chemical, petroleum, textile, medical, food, machinery and other industries ( extruded, expanded) and cold drawn (rolled) seamless tubes.

16. stainless steel seamless pipes for fluid transportation (gb/t14976-2002) are hot-rolled (extruded, expanded) and cold-drawn (rolled) seamless pipes made of stainless steel for fluid transportation.

17. special-shaped seamless pipe is a general term for seamless pipes with cross-sectional shapes other than round pipes. according to the different shape and size of the steel pipe section, it can be divided into equal wall thickness special-shaped seamless pipe (code d), unequal wall thickness special-shaped seamless pipe (code bd), variable diameter special-shaped seamless pipe (code bj). special-shaped seamless pipes are widely used in various structural parts, tools and mechanical parts. compared with round pipes, special-shaped pipes generally have larger moments of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce structural weight and save steel.

18. seamless steel pipes for low-temperature pipelines (gb/t18984-2003) are seamless steel pipes for -45℃～-195℃ low-temperature pressure vessel pipes and low-temperature heat exchanger pipes.

generally, china seamless steel pipes are made of 10, 20, 30, 35, 45 and other high-quality carbon steels such as 16mn, 5mnv and other low-alloy structural steels or 40cr, 30crmnsi, 45mn2, 40mnb and other composite steels by hot rolling or cold rolling. seamless pipes made of low carbon steel such as 10 and 20 are mainly used for fluid transportation pipelines. seamless pipes made of medium carbon steel such as 45 and 40cr are used to manufacture mechanical parts, such as stressed parts of automobiles and tractors.