ASTM A335 High Pressure Steel Pipe

Dec 04, 2025

What is A335 Material

ASTM A335 seamless steel pipe is a standard established by the American Society for Testing and Materials (ASTM) to regulate seamless ferritic alloy steel pipes for high-temperature service. This standard covers various grades, such as P1, P2, P5, P9, P11, P22, P91, etc., each with specific chemical compositions and performance characteristics to meet the demands of different high-temperature and high-pressure environments. ASTM A335 seamless steel pipes are primarily used in high-temperature and high-pressure piping systems in industries like power generation and petrochemicals. In the power sector, they are commonly employed in components such as boiler superheaters, reheaters, and main steam pipes. These components must withstand high-temperature and high-pressure steam impacts, requiring exceptional high-temperature strength, oxidation resistance, and creep resistance from the pipe material.

A335 Alloy Steel Pipe specification

Product Name	Alloy Steel Pipe
Material	Alloy Steel
Pipe Length	Single Random Length and double Random Length.SRL:3M-5.8M DRL:10-11.8M or As clients requested length
Size	Size 1/4" to 24" Outside Diameter 13.7 mm to 609.6 mm
Wall thickness	SCH10, SCH20, SCH30, STD, SCH40, SCH60, SCH80, SCH100 SCH120, SCH160, XS, XXS
Standard	ASTM A 335 Grade P1, P2, P5, P9, P9A, P11, P22.ASTM A213 T1B, T1, T2, T5, T9, T9A, T11, T12, T22.A199 T5, T9, T11, T22. DIN 17175 15 Mo 3, 13 Cr Mo 44, 10 Cr Mo 910, 14 Mo V 63, X 20 Cr Mo V 121. JIS G3458/G3462/3467
Applications	1.Fluid pipe 2. Power Plant 3. Structure pipe 4. High and low pressure Boiler tube 5. Seamless steel tubes for petroleum cracking 6. Conduit pipe 7. Scaffolding pipe pharmaceutical and ship building etc
Certificate	ISO/PED/TUV/SGS/LR/BV
Main Market	Asia, Middle East, Europe, America, Africa, Australia, etc

A335 Seamless Alloy Steel Pipe for high termperature service Chemical Composition(%):

Grade	UNS Designation	Composition, %
		Carbon	Manganese	Phosphorus,	Sulfur	Silicon	Chromium	Molybdenum	Others
		Carbon	Manganese	max	max	Silicon	Chromium	Molybdenum	Others
P1	K11522	0.10–0.20	0.30–0.80	0.025	0.025	0.10–0.50	-	0.44–0.65	-
P2	K11547	0.10–0.20	0.30–0.61	0.025	0.025	0.10–0.30	0.50–0.81	0.44–0.65	-
P5	K41545	0.15 max	0.30–0.60	0.025	0.025	0.50 max	4.00–6.00	0.45–0.65	-
P9	S50400	0.15 max	0.30–0.60	0.025	0.025	0.25–1.00	8.00–10.00	0.90–1.10	-
P11	K11597	0.05–0.15	0.30–0.60	0.025	0.025	0.50–1.00	1.00–1.50	0.44–0.65	-
P12	K11562	0.05–0.15	0.30–0.61	0.025	0.025	0.50 max	0.80–1.25	0.44–0.65	-
P15	K11578	0.05–0.15	0.30–0.60	0.025	0.025	1.15–1.65	-	0.44–0.65	-
P21	K31545	0.05–0.15	0.30–0.60	0.025	0.025	0.50 max	2.65–3.35	0.80–1.06	-
P22	K21590	0.05–0.15	0.30–0.60	0.025	0.025	0.50 max	1.90–2.60	0.87–1.13	-
P23	K41650	0.04–0.10	0.10–0.60	0.03	0.01	0.50 max	1.90–2.60	0.05–0.30	V 0.20–0.30
									Cb 0.02–0.08
									B 0.0005–0.006
									N 0.030 max
									Al 0.030 max
									W 1.45–1.75
P91	K91560	0.08–0.12	0.30–0.60	0.02	0.01	0.20–0.50	8.00–9.50	0.85–1.05	V 0.18–0.25
									N 0.030–0.070
									Ni 0.40 max
									Al 0.04 max
									Cb 0.06–0.10
P92	K92460	0.07–0.13	0.30–0.60	0.02	0.01	0.50 max	8.50–9.50	0.30–0.60	V 0.15–0.25
									N 0.03–0.07
									Ni 0.40 max
									Al 0.04 max
									Cb 0.04–0.09
									W 1.5–2.00
									B 0.001–0.006

A335 Cr-Mo alloy steel pipe Mechanical Properties:

A335 Cr-Mo Alloy Steel Pipe Mechanical Properties:

‌Heat Treatment Technology‌

Through processes like full annealing, normalizing with tempering, residual stress from processing is eliminated and grain structure is refined. Key steps include:

Heating to 900-950°C followed by air cooling

Tempering at 650-700°C

Strict control of heating and cooling rates