Currently China's p11 steel pipe consumption accounted for the proportion of total steel is only half of the developed countries, p11 steel pipe use areas to expand for the development of the industry to provide a broader space. According to the research of China Special Steel Association p11 steel pipe branch, the future demand for China's high-pressure p11 steel pipe long steel can reach an average annual growth of 10-12%.
1. seamless steel pipe
Because of its manufacturing process, it is divided into hot-rolled (extrusion) seamless steel pipe and cold-drawn (rolled) seamless steel pipe two. Cold-drawn (rolled) tube is also divided into two kinds of round and shaped tube.
a. Process Overview
Hot Rolled (Extruded Seamless Steel Pipe): round billet→heating→piercing→three-roll tilting, continuous rolling or extrusion→detubing→dimensioning (or reduction)→cooling→billet→straightening→hydraulic test (or flaw detection)→marking→warehousing.
Cold-drawn (rolled) seamless steel pipe: round billet→heating→piercing→heading→annealing→acid washing→oil coating (copper plating)→multiple cold-drawn (cold-rolled)→billet pipe→heat treatment→straightening→hydraulic test (flaw detection)→marking→warehousing.
b. Seamless steel pipe, depending on its use, is divided into several varieties as follows:
GB/T8162-2008 (seamless steel pipe for structure). Mainly used for general structure and mechanical structure. Its representative materials (grades): carbon steel 20, 45 steel; alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo and so on.
GB/T8163-2008 (seamless steel pipe for transportation of fluids). Mainly used in engineering and large-scale equipment to transport fluid pipelines. The representative material (grade) for 20, Q345, etc..
GB3087-2008 (low and medium pressure boiler seamless steel pipe). Mainly used for industrial boilers and domestic boilers to transport low and medium pressure fluid piping. The representative material is 10, 20 steel.
GB5310-2008 (high-pressure boiler seamless steel pipe). Mainly used in power stations and nuclear power plant boilers on the high temperature, high pressure transportation fluid container and piping. The representative materials are 20G, 12Cr1MoVG, 15CrMoG and so on.
GB5312-1999 (carbon steel and carbon manganese steel seamless steel pipe for ships). Mainly used for ship boilers and superheaters with I, II level pressure-resistant pipe and so on. Representative materials are 360, 410, 460 steel grade, etc..
GB6479-2000 (high-pressure chemical fertilizer equipment with seamless steel pipe). Mainly used for fertilizer equipment to transport high temperature and high pressure fluid pipeline. The representative materials are 20, 16Mn, 12CrMo, 12Cr2Mo and so on.
GB9948-2006 (seamless steel pipe for petroleum cracking). Mainly used in petroleum refinery boiler, heat exchanger and its transportation fluid pipeline. Its representative materials are 20, 12CrMo, 1Cr5Mo, 1Cr19Ni11Nb and so on.
GB18248-2000 (seamless steel pipe for gas cylinder). Mainly used for making all kinds of gas and hydraulic cylinders. Its representative materials are 37Mn, 34Mn2V, 35CrMo and so on.
GB/T17396-1998 (hot rolled seamless steel pipe for hydraulic strut). Mainly used in the production of coal mine hydraulic support and cylinder, column, and other hydraulic cylinder, column. Its representative materials are 20, 45, 27SiMn and so on.
GB3093-1986 (high pressure seamless steel pipe for diesel engine). Mainly used for diesel engine injection system high-pressure oil pipe. Its steel pipe is generally cold-drawn pipe, and its representative material is 20A.
GB/T3639-1983 (cold-drawn or cold-rolled precision seamless steel pipe). Mainly used for mechanical structure, carbon pressure equipment, requiring high dimensional accuracy, good surface finish steel tube. Its representative material 20, 45 steel and so on.
GB/T3094-1986 (cold drawn seamless steel pipe shaped steel pipe). Mainly used in the production of various structural components and parts, its material for high-quality carbon structural steel and low alloy structural steel.
GB/T8713-1988 (Precision I.D. Seamless Steel Tubes for Hydraulic and Pneumatic Cylinders). Mainly used in the production of hydraulic and pneumatic cylinder barrel with precision internal diameter size of cold drawn or cold rolled seamless steel tube. Its representative material is 20, 45 steel and so on.
GB13296-1991 (stainless steel seamless steel pipe for boiler and heat exchanger). Mainly used in chemical enterprises, boilers, superheaters, heat exchangers, condensers, catalytic tubes and so on. Used for high temperature, high pressure, corrosion-resistant steel pipe. Its representative materials are 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti and so on.
GB/T14975-1994 (structural stainless steel seamless steel pipe). Mainly used for general structure (hotel, restaurant decoration) and chemical enterprise mechanical structure with atmospheric and acid corrosion resistance and have a certain strength of the steel pipe. Its representative materials are 0-3Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti and so on.
GB/T14976-1994 (stainless steel seamless steel pipe for fluid transportation). Mainly used for conveying corrosive media pipeline. The representative materials are 0Cr13, 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr17Ni12Mo2, 0Cr18Ni12Mo2Ti and so on.
YB/T5035-1993 (seamless steel pipe for automobile half shaft casing). Mainly used in the production of automotive half shaft casing and drive axle housing axle tube with high quality carbon structural steel and alloy structural steel hot rolled seamless steel pipe. Its representative materials are 45, 45Mn2, 40Cr, 20CrNi3A and so on.
API SPEC5CT-1999 (casing and tubing specification), is the American Petroleum Institute (American Petreleum Instiute, abbreviated as API) compiled and released in the world common. Among them: Casing: Tubing that extends from the surface of the ground into the drilled well and serves as a well-wall liner, with the tubing connected to each other by clamps. The main materials are J55, N80, P110 and other steel grades, as well as hydrogen sulfide corrosion-resistant C90, T95 and other steel grades. Its low steel grade (J55, N80) can be welded steel pipe. Oil pipe: the pipe inserted into the casing from the ground surface up to the oil layer, which is connected between the pipes through the joints or the whole. Its role is to pump the oil layer oil through the oil pipe to the ground. The main materials are J55, N80, P110, and antihydrogen sulfide corrosion of C90, the American Petroleum Institute compiled and released in the world common.