A. Overview of process flow
Hot rolling (extrusion seamless steel tube) : round tube billet → heating → perforation → three-high cross rolling, continuous rolling or extrusion → tube release → sizing (or reducing) → cooling → billet → straightening → hydrostatic test (or flaw detection) → marking → storage.
Cold-drawn (rolled) seamless steel tube: round tube billet → heating → perforation → heading → annealing → pickling → oil coating (copper plating) → multi-pass cold drawing (cold rolling) → billet → heat treatment → straightening → hydrostatic test (flaw detection) → marking → storage.
B. Seamless steel pipes are divided into the following varieties because of their different uses:
Seamless steel tubes for structural use Mainly used in general structure and mechanical structure. Its representative material (grade) : carbon steel 20, 45 steel; Alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo, etc.
GB/T8163-1999 seamless steel tubes for conveying fluids Mainly used in engineering and large equipment on the transport of fluid pipeline. Representative materials (brand) for 20, Q345, etc.
Gb3087-1999 (seamless steel tubes for low and medium pressure boilers) It is mainly used in the pipeline of industrial boiler and domestic boiler conveying low and medium pressure fluid. Representative material for 10, 20 steel.
GB5310-1995 (seamless steel tubes for high-pressure boilers) It is mainly used for high temperature and high pressure conveying fluid collecting box and pipeline on the boiler of power station and nuclear power station. The representative material is 20G, 12Cr1MoVG, 15CrMoG, etc.
Seamless steel tubes of carbon steel and carbon-manganese steel for ships GB5312-1999 Mainly used in Marine boiler and superheater for CLASS I, II pressure tube, etc. Representative material for 360, 410, 460 steel class.
GB1479-2000 (seamless steel tubes for high-pressure fertilizer equipment) Mainly used for conveying high temperature and high pressure fluid pipeline on fertilizer equipment. Representative materials are 20, 16Mn, 12CrMo, 12Cr2Mo, etc.
GB9948-1988 (seamless steel tubes for petroleum cracking) It is mainly used in boilers, heat exchangers and fluid conveying pipelines of petroleum smelters. Its representative materials are 20, 12CrMo, 1Cr5Mo, 1Cr19Ni11Nb and so on.
GB18248-2000 (seamless steel tube for gas cylinders) Mainly used for making all kinds of gas and hydraulic cylinders. Its representative materials are 37Mn, 34Mn2V, 35CrMo, etc.
GB/T17396-1998 (hot rolled seamless steel tubes for hydraulic struts) Mainly used in the production of coal mine hydraulic support and cylinders, columns, and other hydraulic cylinders, columns. Its representative materials are 20, 45, 27SiMn, etc.
GB3093-1986 (seamless high-pressure steel tubes for diesel engines) Mainly used for high pressure oil pipe of diesel engine injection system. Its steel pipe is generally cold drawn pipe, its representative material is 20A.
GB/T3639-1983 (cold drawn or cold rolled precision seamless steel tube) Mainly used for mechanical structure, carbon pressing equipment, high dimensional precision, good surface finish steel pipe. Its representative material 20, 45 steel, etc.
GB/T3094-1986 (cold-drawn seamless steel tube shaped steel tube) Mainly used for making various structural parts and parts, its material is high quality carbon structural steel and low alloy structural steel.
Seamless precision inner diameter steel tubes for hydraulic and pneumatic cylinders GB/T8713-1988 It is mainly used for making cold drawn or cold rolled seamless steel tubes with precise inner diameter for hydraulic and pneumatic cylinder. Its representative material is 20, 45 steel, etc.
GB13296-1991 seamless stainless steel tubes for boilers and heat exchangers It is mainly used in boilers, superheaters, heat exchangers, condensers and catalytic tubes in chemical enterprises. High temperature, high pressure and corrosion resistant steel tubes. Its representative materials are 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti and so on.
GB/T14975-1994 seamless steel tubes for structural use Mainly used in general structure (hotel, hotel decoration) and chemical enterprise mechanical structure used in the atmosphere, acid corrosion and has a certain strength of steel pipe. Its representative materials are 0-3Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti and so on.
GB/T14976-1994 (seamless stainless steel tubes for fluid transport) Mainly used for conveying corrosive medium pipeline. Representative materials are 0Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr17Ni12Mo2, 0Cr18Ni12Mo2Ti and so on.
YB/T5035-1993 (seamless steel tube for automobile semi-axle sleeve pipe) It is mainly used for the production of high quality carbon structural steel and alloy structural steel hot rolled seamless steel tube for the axle sleeve of automobile and the axle housing of drive axle. Its representative materials are 45, 45Mn2, 40Cr, 20CrNi3A and so on.
Post time: Sep-16-2021