Seamless Steel Pipe

Seamless Steel Pipe

The seamlesssteel pipe usually has a specification of 8-1240×1-200 mm, which represents outer diameter ×wall thickness (unit: mm). According to different production methods, it can bedivided into hot-rolled one and cold-rolled (drawn) one. In general, thehot-rolled type is divided into general steel pipe, low and medium pressureboiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainlesssteel pipe, petroleum cracking tube, geological steel pipe, and so on. The cold-rolled(drawn) seamless steel pipe is also applicable to the above classification andincludes extra precision steel tube, carbon thin-wall steel tube, alloythin-wall steel pipe, stainless steel thin-wall tube, shaped steel tube, etc.

The hot-rolled seamless pipe generally comes with an outer diameter of over32mm and wall thickness of 2.5-75mm. In addition, the cold-rolled one achievesan outer diameter of 6mm and wall thickness of 0.25mm, while the outer diameterof the thin-wall tube can reach 5mm with the wall thickness less than0.25mm.  This indicates that thecold-rolled one has a higher dimensional accuracy than the hot-rolled one.However, the hot-rolled piece enjoys smaller deformation resistance and largerdeformation amount, due to the high rolling temperature. In the piping andplumbing system, hot-rolled tube is often used with the pipe diameter more than57mm, while the cold-drawn (rolled) pipe is commonly used with the diameterless than 57mm.

Generally, theseamless steel pipe is made of 10 #, 20 #, 30 #, 35 #, 45 #, and other highquality carbon structural steel, or 16Mn, 5MnV, and other low-alloy structuralsteel, or 40Cr, 30CrMnSi, 45Mn2, 40MnB, and other alloy structural steel. Theone made of 10 #, 20 # and other low-carbon steel is commonly used forconveyance of fluids. The one made of 40Cr, 45 #, and other medium carbon steelis usually used for the manufacture of mechanical parts of automobiles,tractors, etc. All the pipes must go through the flattening test to ensureenough strength. The hot-rolled steel pipe can be delivered directly in thestate of hot rolling with or without special heat treatment, while the finalcold-rolled pipe is processed with heat treatment.

Seamless SteelPipe

The seamless steel tube with hollow cross-section iswidely used to convey fluids such as oil, gas, water and some solid materials.Compared with round steel and other solid steel, the steel pipe is lighterwhile maintaining the same bending and torsion resistance. Hence, thiseconomical product is broadly applied in the manufacture of structural partsand mechanical parts, such as oil drill pipe, automobile transmission shaft,bicycle frame, and steel scaffolding used on construction sites. When used to manufactureannular parts like rolling bearing ring and lifting jack, it can improve thematerial utilization, simplify the manufacturing process, thus saving materialand machining time. What’s more, it is also an indispensable material in themanufacture of various conventional weapons, such as gun and cannon.

According todifferent cross-sectional area shapes, the steel pipe can be divided into roundpipe and shaped pipe. As a circle gains the largest area among other shapeswith the same perimeter, so the round pipe can transport more fluids than thepipe of other shapes. In addition, the ring cross section can withstandinternal or external radial pressure force more uniformly, so the vast majorityof steel pipe is circular in cross section. However, the round tube has somelimitations. For example, under the condition of plane bending, the circulartube is not as good as square, rectangular tube in bending strength. Hence, thesquare or rectangular tube is frequently used in the manufacture of farmmachinery skeleton, steel and wood furniture. Furthermore, other cross-sectionshapes of the pipe are also available in accordance with different uses.

Pipe Types with DifferentApplications
1. Structural seamless steelpipe (GB/T8162-2008) is used for general structure and mechanical structure.
2. Fluid seamless steel pipe (GB/T8163-2008) is used for general conveyance ofwater, oil, gas and other fluids.
3. Low and medium pressure boiler seamless steel pipe (GB3087-2008) is a hotrolled or cold rolled (drawn) pipe made of high-quality carbon structuralsteel. It can be used in the manufacture of a variety of superheated steampipes and hot boiling water pipes for low and medium pressure boiler, as wellas superheated steam tubes and arch tubes for locomotive boiler.
4. High pressure boiler seamless pipe (GB5310-2008) is a high-quality carbonsteel, alloy steel and heat-resistant stainless steel pipe used in themanufacture of heating water tube for high pressure boiler.
5. Chemicalfertilizer seamless pipe (GB6479-2000) is a high quality carbon structuralsteel and alloy steel pipe applicable to the chemical equipment and pipelinewith the working temperature of -40 ~ 400 ℃ and working pressure of 10 ~30Ma.
6. Petroleum seamless steel pipe (GB9948-2006) is applicable to petroleumrefinery furnace tubes, heat exchangers and pipeline.
7. Geological drilling steel pipe (YB235-70) is provided for the geologicaldepartment to conduct core drilling. It can be divided into drill pipe, drillcollar, core pipe, casing and precipitation tube, etc. according to differentuses.
8. Diamond core drilling seamless steel pipe (GB3423-82) is applicable to drillpipe, core rod, casing used for diamond core drilling.
9. Oil drill pipe (YB528-65) is an internal or external upset pipe used in oildrilling. It has sub-threading and threading two types, with the threading pipeconnected with joints and non-threading pipe welded and linked with tooljoints.
10. Ship carbon steel seamless steel pipe (GB5213-85) is used for ship class Iand II pressure piping, boiler, and superheater,with the temperature for pipe wall not exceeding 450 ° C.
11. Automobile axle casing seamless steel pipe (GB3088-82) is a hot-rolled pipewhich is made of quality carbon structural steel and alloy structuralsteel.  It is suitable for themanufacture of automobile axle tube.
12. Diesel engine high pressure oil pipe (GB3093-2002) is a cold-drawn one usedfor high-pressure tubing in diesel injection system.
13. Hydraulic and pneumatic cylinder seamless steel pipe with precisioninternal diameter (GB8713-88) is manufactured with cold drawing or coldrolling.
14. Cold drawn orcold rolled precision seamless steel pipe (GB3639-2000) with high dimensionalaccuracy and good surface finish can greatly reduce the mechanical processingtime, improve material utilization, and help to improve the product qualitywhen used in the manufacture of mechanical structure, hydraulic equipment, etc.
15. Structural stainless steel seamless pipe (GB/T14975-2002) is a hot-rolled(extrusion, expansion) and cold drawn (rolled) tube. It is widely used toproduce anti corrosion pipeline, structural parts, and components in chemical,petroleum, textile, medical, food, machinery and other industries.
16. Fluid transportation stainless steel seamless pipe (GB/T14976-2002) is hotrolled (extrusion, expansion) or cold drawn (rolled) for conveying fluids.
17. Shaped seamless steel pipe is the general term for pipes of other crosssection shapes in addition to the circular tube. According to different shapesand sizes of cross-section, the pipe can be further divided into equal wallthickness type (code D), unequal wall thickness type (code BD), and variablediameter type (code BJ). It is widely used in various structural parts, toolsand mechanical parts. Compared with the round tube, the shaped pipe generallyhas a greater moment of inertia and cross-section modulus and better bendingand torsion resistance, so as to greatly reduce structural weight and savesteel consumption.
18. Low-temperature seamless steel pipe (GB/T18984-2003) applies to -45 ° C ~-195 ° C cryogenic pressure vessel piping and low temperature heat exchangertube.

1. Structural Seamless Steel Pipe
Nationalstandard: GB/T8162-2008
Material: 10, 20,35, 45, 40Mn2, 45Mn2, 27SiMn, 20Cr, 40Cr, 20CrMo, 35CrMo, 38CrMoA1, 50CrV,30CrMnSi ASTM A500-98
Internationalstandard: ASTM A501-98 ASTN A519-98 JIS G3441-1994

2. Fluid Conveyance Seamless Steel Pipe　
Nationalstandard: GB/T8163-2008
Material: 10#,20#, Q295, Q345
Internationalstandard: ASTM A53-98 ASTM A192 ASME S192 JIS G3452-1998 FIS G3454-1998 DIN1629-1984

3. Oil Well Pipe, Coupling Feed Tube,Line Pipe
Nationalstandard: API SPEC 5CT APE SPEC 5L
Material: J55,N80A,B,X42　
Internationalstandard: API　

4. High Pressure Boiler Seamless Pipe
National standard:GB5310-2008
Material: 20G,20MnG, 25MnG, 15MoG, 20MoG, 12Cr1MoVG, 15CrMoVG, 12Cr2MoG, 12Cr2MoWVTiB,12Cr3MoVSiTiB
International standard:ASTM A106-96a, ASTM A210C, ATSM A213-95a, JIS G3461-1988, JIS G3462-1998, DIN17175-1979, BS3059: Part 2: 1990

5. Low and Medium Pressure Boiler Seamless Steel Pipe
Nationalstandard: GB3087-2008
Material: 10#, 20#
Internationalstandard: ASTM A179, ASTM A192, ASTM SA179,SA192, BS3059　

6. Chemical Fertilizer High PressureSeamless Steel Pipe
Nationalstandard: GB6479-2000
Material: 10#,20G, Q345, Q390, 10MoVNb, 12CrMo, 15CrMo, 12Cr2Mo
Internationalstandard: ISO 9329-2-1997, ASTM A161-94

7. Petroleum Cracking Seamless Steel Pipe
Nationalstandard: GB9948-2006
Material: 10#,20#, 12CrMo, 15CrMo, 1Cr2Mo, 1Cr5Mo
Internationalstandard: JIS G3441-1988

8. Automobile Axle Casing Seamless Steel Pipe
Nationalstandard: Q/OHAD001-1997 YB/T5035-1998
Material: 45Mn2,45#, 25MnCr
International standard:DIN 1629-1984

9. Hydraulic Prop Hot Rolled SeamlessSteel Pipe
Standard:Q/OHAD010-2007 GB/T17398-2007
Material: 27SiMn

10. Ship Carbon, Carbon-Manganese Steel Seamless Pipe
Standard:GB/T5312-1999
Material: Q320,Q360, Q410, Q460, Q490
Internationalstandard: DIN 2391-1994

11. Cold Drawn Precision Seamless SteelPipe
Standard:GB/T3639-2000 GB/T8713-88
Material: 10#,20#, 35#, 45#, 30CrMo

12. Geological Drilling Seamless SteelPipe
Standard:YB/T5052-93 YB235-70
Material: DZ40,DZ50

13. Cannon Seamless Steel Pipe
Standard: YBn1-86
Material: 40Mn2,D60

14. Mandril Seamless Steel Pipe
Standard:Q/OHAD003-94
Material: 1CrMo

15. Bearing Seamless Steel Pipe
Standard:YB/Z12-77YJZ84
Material: GCr15

16. Ribbed Rebar Connecting Sleeve Seamless Steel Pipe
Standard:Q/OHAD011-1997a
Material: 10#,20#

17. Gas Cylinder Seamless Steel Pipe
Material: 34Mn2V,30CrMo, 35CrMo, 45#

The seamless steel pipe is manufactured conforming to ISO9001 international qualitymanagement system, ISO14001 environmental management system and ISO18001occupational health safety control system. Our carbon steel pipes, alloy steelpipes and stainless steel pipes can be provided with various specifications andmaterials. In collaboration with TianjinPipe Group Corp, Shanghai BaoshanSteel Corporation, ChengduSteel Factory, Jiangsu Chengde Steel Factory, Baotou Steel (Group) Corporation,Anshan Iron and Steel Corp,and steel pipe manufactures in US, Britain,Japan, Germany, Italy, etc. They are widely used inpipeline projects in petroleum, chemical, natural gas, nuclear power,thermoelectricity, metallurgy, thermal pipe network, shipbuilding, papermaking,construction, etc.