Description

Carbon steel pipes are steel pipes made primarily of carbon steel (carbon content typically ≤2.1%). They combine high strength, good machinability, and cost advantages, but have poor corrosion resistance. Based on manufacturing processes, they are mainly divided into seamless pipes (hot-rolled/cold-drawn) and welded pipes (straight seam/spiral/high-frequency welded), and can be further subdivided according to application and steel grade.

Characteristics and Classification of Carbon Steel Pipes:

1. Characteristics: High strength, good toughness, excellent weldability and machinability, and relatively low cost; however, they have poor corrosion resistance (requiring galvanizing, coating, or alloying for improvement), may become brittle at low temperatures, and are not resistant to high temperatures (generally, the upper limit of operating temperature is approximately 350–450℃, depending on the steel grade); they have a relatively high density and weight, and lack insulation properties.

2. Classification (by process): Seamless carbon steel pipes (hot-rolled, cold-drawn/rolled), welded carbon steel pipes (straight seam welded ERW/LSAW, spiral welded pipes, high-frequency resistance welded HFW); By steel grade/application: Structural pipes (e.g., 20, 45, GB/T 8162), fluid transport pipes (e.g., 20, GB/T 8163), boiler tubes (e.g., 20G, GB/T 5310), pipeline steel pipes (e.g., X42–X80, GB/T 9711/API 5L), machinery manufacturing pipes (high carbon steel such as 45, requiring heat treatment); By cross-section: round pipes, special-shaped pipes (square, rectangular, etc.).

Applications of Carbon Steel Pipes:

Carbon steel pipes have a wide range of applications, mainly covering fluid transportation, mechanical structures, energy infrastructure, and emerging energy fields, specifically as follows:

1. Fluid and Gas Transportation: Used for transporting oil, natural gas, water, coal gas, steam, and chemical media (such as water supply, drainage, and gas pipelines). Common materials include 20 and 16Mn, conforming to standards GB/T8163 and GB/T9711; high-frequency welded pipes (HFW) or spiral pipes are mostly used for municipal and long-distance pipelines.

2. Mechanical Manufacturing and Structural Components: Medium and high carbon steel (such as 45) is used for load-bearing parts such as automobile drive shafts, hydraulic cylinders, machine tool spindles, and bearing sleeves; structural carbon steel (such as Q235 and Q345) is used for load-bearing frames in factory buildings, bridges, ships, and tower cranes (GB/T8162).

3. Boilers and Heat Exchange Equipment: Low and medium pressure boiler tubes (20, 20G, GB3087), high pressure boiler tubes (GB5310), petroleum cracking furnace tubes (GB9948), etc., with a typical temperature resistance ≤550℃.

4. Energy and Emerging Applications: Used for CO₂ enhanced oil recovery and storage transportation (X65–X80 grade HFW pipes), hydrogen transportation (X52 and below carbon steel or low alloy steel welded pipes), salt cavern compressed air energy storage pipelines (corrosion protection assessment required).

5. Special Engineering Fields: Geological drilling pipes, oil casing/drill pipe (API 5CT), fertilizer high-pressure equipment (GB6479, –40~400℃), marine piping systems, diesel engine high-pressure oil pipes, etc.

Specifications of Carbon Steel Pipe:

Feature	seamless	welded, seamed
Types	hot rolled seamless carbon steel pipe cold rolled seamless carbon steel pipe cold drawn seamless carbon steel pipe	Electric-Resistance Welded Pipe Longitudinal Welded Pipe Spiral Welded Pipe
Standard	astm a53, a333, a335, a355, a312, a179, a106, a106b, a105, a192, a519, a210, a671, a672, sa213 jis G3445/3454/3455/3441/3444 *din17175, din1629, din1615, din2458, en10210	a672, a795, a252, a53b, a53, a135, a500
Technique	cold rolled, hot rolled, cold drawn	erw straight seam or spiral seam(efw available)
Outer Diameter	50mm-630mm (1.96”-24.8” hot rolled seamless steel pipe); 5mm-100mm (0.19”-3.93” cold rolled/drawn seamless steel pipe)	20mm-600mm (0.78”- 23.6” straight seam weld steel pipe); 219mm-2020mm (8.62”-79.52” spiral seam weld steel pipe).
Wall Thickness	3mm-20mm (0.11”-0.78” hot rolled seamless steel pipe); 0.5mm-3mm (0.01”-0.11” cold rolled/drawn seamless steel pipe).	1.0mm-12mm (0.03”-0.47” straight seam weld steel pipe); 3mm-16mm (0.11”-0.62” spiral seam weld steel pipe).
Length	500mm-13000mm (19.6”-511.8” or random length)	300mm-12000mm(11.8”-472.4” or random length)
Grade	4140/4145/4130/4135/3087, ss400, c45, s235, s275jr, s355jr, s355j2h, p235gh tc2, p235 tr1, p235 tr2, sae1040/1020/1010/1070/1015/1018, stpg307, 40cr, 34crmo4, 20gr, 37mn, 16mnr, 20#, q345c, q195, q235c, 195c, s45c, st37/45/20/52/33 etc	sa 53 gr b, p91, q235b, q345b, q235, q195, st37, st44, s355, s135, s185, s235jr, s275jr, s355jr, etc
Shape	round, square, rectangular
Pipe Ends	plain ends, beveled ends etc
Surface Treatment	shot blasting/galvanized/painted as customer needs
Customized	length, diameter, wall thickness etc
Certificate	CE, ISO
Supply ability	20000 ton/month
Delivery Time	stock size 10 days, customize size 15-25 days, large quantity please contact with our sales person.
Packing	option one: plastic caps covered on both ends of pipes;
	option two: woven bag wrapped outside the pipes;
	option three: tied in bundle
Application	oil/gas/water fluid transportation or construction, hydraulic precision machinery parts/power/boiler/petrochemical/building industry etc
Inspection	accept the third party to check the goods quantity and quality
Moq	please chat with us about your order
Attention: please send us your order requirements to get our details with current best price within 1 hour

Standards and Classifications

Steel Grade	GB China	JIS Japan		ASTM America	Din German
Steel Grade	Steel Grade	Steel Grade	Steel Standard	Steel Grade	Steel Grade	Material	Steel Standard
Carbon Steel Pipe/Tube	（Q235）Steel Pipe/Tube	GGP STPY41	G3452 G3457	ASTM (A53 F) A283-D	(St33)	1.0033	DIN1626
	10#Steel Pipe/Tube	STPG38	G3454	ASTM A135-A A53-A	(St37)	1.011	DIN1626
		STPG38	G3456	ASTM A106-A	St37-2	1.0112	DIN17175
		STS38	G3455		St35.8 St35.4	1.0305 1.0309	DIN1629/4
		STB30	G3461	ASTM A179-C A214-C	St35.8	1.0305	DIN17175
		STB33	G3461	ASTM A192 A226	St35.8	1.0305	DIN17175
		STB35	G3461		St35.8	1.0305	DIN17175
	20#Steel Pipe/Tube	STPG42	G3454	ASTM A315-B A53-B	(St42) St42-2	1.0130 1.0132	DIN1626
		STPT42	G3456	ASTM A106-B	St45-8	1.0405	DIN17175
		STB42	G3461	ASTM A106-B	St45-8	1.0405	DIN17175
		STS42	G3455	ASTM A178-C A210-A-1	St45-4	1.0309	DIN1629/4
Low Alloy Steel Pipe/Tube	16MnSteel Pipe/Tube	STS49 STPT49	G3455 G3456	ASTM A210-C	St52.4 St52	1.0832 1.0831	DIN1629/4 DIN1629/3
Low Alloy Steel Pipe/Tube	15MnVSteel Pipe/Tube	STBL39	G3464
Low Temperature Steel Pipe/Tube	16MnSteel Pipe/Tube	STPL39	G3460	ASTM A333-1.6	TT St35N	1.0356	SEW680
	15MnVSteel Pipe/Tube	STBL39	G3464	ASTM A334-1.6	TT St35N	1.0356	SEW680
	09Mn2VSteel Pipe/Tube			ASTM A333-7.9 A334-7.9	TT St35N	1.0356	SEW680
	(06A1NbCuN)Steel Pipe/Tube	STPL46 STBL	G3460 G3464	ASTM A333-3.4 A334-3.4	10Ni14	1.5637	SEW680
	(20Mn23A1)Steel Pipe/Tube			ASTM A333-8 A334-8	X8Ni9	1.5662	SEW680
Heat resistant Steel Pipe/Tube	16MoSteel Pipe/Tube	STPA12 STBA12、13	G3458 G3462	ASTM A335-P1、A369-FP1 A250-T1、A209-T1	15Mo3	1.5414	DIN17175
	12CrMoSteel Pipe/Tube	STBA20	G3462	ASTM A335-P2、A369-FP2 A213-T2
	15CrMoSteel Pipe/Tube	STPA22 STBA22	G3458 G3462	A335-P12、A369-FP12 A213-T12	13CrMo44	1.7335	DIN17175
	12Cr1MoVSteel Pipe/Tube	STPA23 STBA23	G3458 G3462	ASTM A335-P11、A369-FP12 A199-T11、A213-T11
	Cr2Mo 10MoWVNbSteel Pipe/Tube	STPA24 STBA24	G3458 G3462	ASTM A335-P22、A369-FP22 A199-T22、A213-T22	10CrMo910	1.738	SEW610
	Cr5MoSteel Pipe/Tube	STPA25 STBA25 STPA26 STBA26	G3458 G3462 G3458 G3462	ASTM A335-P5、A389-FP5 A213-T5 A335-P9、A369-FP9 A199-T9、A213-T9	12CrMo195	1.7362	DIN17175