Round steel -- tube blank -- Inspection -- Heating -- perforation -- sizing -- hot rolling -- flat head -- Inspection -- pickling -- spherical annealing -- cold drawing -- forming -- mouth alignment -- inspection.

1. Seamless steel pipe for structure (GB / T8162-1999) is a seamless steel pipe for general structure and mechanical structure. 2. Seamless steel pipe for fluid transportation (GB / t8163-1999) is a general seamless steel pipe used to transport water, oil, gas and other fluids. 3. Seamless steel pipe for low and medium pressure boiler (GB3087-1999) is a high-quality carbon structural steel hot-rolled and cold drawn (rolled) seamless steel pipe for manufacturing superheated steam pipe, boiling water pipe of low and medium pressure boiler and superheated steam pipe, large smoke pipe, small smoke pipe and arch brick pipe for locomotive boiler. 4. Seamless steel pipe for high pressure boiler (GB5310-1995) 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 boiler with high pressure and above. 5. High pressure seamless steel pipe for fertilizer equipment (GB6479-2000) is a high-quality carbon structural steel and alloy steel seamless steel pipe suitable for chemical equipment and pipelines with working temperature of - 40 ~ 400 ℃ and working pressure of 10 ~ 30mA. 6. Seamless steel pipe for petroleum cracking (gb9948-88) is a seamless steel pipe suitable for furnace tubes, heat exchangers and pipes in petroleum refineries. 7. The steel pipe for geological drilling (yb235-70) is the steel pipe used by the geological department for core drilling. According to the purpose, it can be divided into drill pipe, drill collar, core pipe, casing and sedimentation pipe. 8. Seamless steel pipe for diamond core drilling (gb3423-82) is a seamless steel pipe for drill pipe, rock core rod and casing used for diamond core drilling. 9. Oil drilling pipe (yb528-65) is a seamless steel pipe used for internal or external thickening at both ends of oil drilling. The steel pipe is divided into turning wire and non turning wire. The turning wire pipe is connected with the joint, and the non turning wire pipe is connected with the tool joint by butt welding. 10. Marine carbon steel seamless steel pipe (gb5213-85) is a carbon steel seamless steel pipe for manufacturing class I pressure pipe system, class II pressure pipe system, boiler and superheater. The working temperature of carbon steel seamless steel pipe wall shall not exceed 450 ℃, and that of alloy steel seamless steel pipe wall shall not exceed 450 ℃. 11. Seamless steel pipe for automobile half shaft sleeve (gb3088-82) is a high-quality carbon structural steel and alloy structural steel hot-rolled seamless steel pipe for manufacturing automobile half shaft sleeve and drive axle housing shaft pipe. 12. High pressure oil pipe for diesel engine (gb3093-2002) is a cold drawn seamless steel pipe for manufacturing high pressure pipe of diesel engine injection system. 13. Precision inner diameter seamless steel pipe (GB8713-88) for hydraulic and pneumatic cylinder barrel is a cold drawn or cold rolled precision seamless steel pipe with precision inner diameter for manufacturing hydraulic and pneumatic cylinder barrel. 14. Cold drawn or cold rolled precision seamless steel pipe (GB3639-2000) is a cold drawn or cold rolled precision seamless steel pipe with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. Selecting precision seamless steel pipe to manufacture mechanical structure or hydraulic equipment can greatly save machining hours, improve material utilization and improve product quality. 15. Stainless steel seamless steel pipe for structure (GB / T14975-2002) is a hot-rolled (extruded, expanded) and cold drawn (rolled) seamless steel pipe made of stainless steel for corrosion-resistant pipes, structural parts and parts widely used in chemical, petroleum, light textile, medical, food, machinery and other industries. 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.