ASME SA335 / ASTM A335 Alloy Steel Pipe Description

A335 alloy pipe is a seamless ferritic alloy steel pipe manufactured according to the ASTM A335 standard for high-temperature applications. It is widely used in high-temperature and high-pressure environments, such as power generation, petrochemicals, steam boilers, and heat exchangers. ASTM A335 seamless pipe exhibits good high-temperature resistance. At high temperatures, the strength and toughness of steel tend to decrease. However, many alloy steel grades in the A335 standard, such as P11, P22, and P91, have undergone special alloy element design and heat treatment processes, allowing them to maintain good mechanical properties at temperatures above 400℃. This is particularly important for high-temperature and high-pressure pipeline systems in thermal power plants and petrochemical plants, as it extends pipeline service life and reduces maintenance frequency.

Standard: ASTM A335

grade:P1, P2,P5,P9,P11,P91,P92

OD:10.3-660mm

WT:1.6-60mm

Length:5.8m-12m or random legth

Technical: Quenching & Tempering

Application: Gas fire power plant, coal fire power plant, headers and steam lines, Feedwater pipes, superheaters, and reheaters.

ASME SA335 / ASTM A335 Standard specification

ASME SA335 / ASTM A335 chrome-moly seamless pipes Chemical Composition

ASTM A335 Low-Alloy Steel (Grades)	UNS equivalent	C≤	Mn	P≤	S≤	Si≤	Cr	Mo
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	0.30~0.60	0.025	0.025	0.5	4.00~6.00	0.44~0.65
P5b	K51545	0.15	0.30~0.60	0.025	0.025	1.00~2.00	4.00~6.00	0.44~0.65
P5c	K41245	0.12	0.30~0.60	0.025	0.025	0.5	4.00~6.00	0.44~0.65
P9	S50400	0.15	0.30~0.60	0.025	0.025	0.50~1.00	8.00~10.00	0.44~0.65
P11	K11597	0.05~0.15	0.30~0.61	0.025	0.025	0.50~1.00	1.00~1.50	0.44~0.65
P12	K11562	0.05~0.15	0.30~0.60	0.025	0.025	0.5	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	0.5	2.65~3.35	0.80~1.60
P22	K21590	0.05~0.15	0.30~0.60	0.025	0.025	0.5	1.90~2.60	0.87~1.13
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
P92	K92460	0.07~0.13	0.30~0.60	0.02	0.01	0.5	8.50~9.50	0.30~0.60

ASME SA335 / ASTM A335 seamless ferritic Alloy-Steel Pipe Mechanical Properties

A335 Low-Alloy Pipe	UNS Number	Yield Strength ksi	Tensile Strength ksi	Elongation %	Rockwell	Brinell
P1	K11522	30	55	30	–	–
P2	K11547	30	55	30	–	–
P5	K41545	40	70	30	–	207 max
P9	S50400	30	60	30	–	–
P11	K11597	30	60	20	–	–
P12	K11562	32	60	30	–	174 max
P22	K21590	30	60	30	–	–
P91	K91560	60	85	20	–	–

Testing Requirements

Transverse/longitudinal: tension and flattening, hardness, bend tests- for material that has been heat-treated in batch furnaces, these tests shall be made on the 5% of the pipes from each heat lot number. For smaller lots, one pipe at a minimum has to be tested

ASTM A335 Gr. P91 shall have a hardness of 250 HB / 265 HV (25 HRC)

Hydro testing: shall be applied to every length of pipe

The non-destructive electric test is optional

Tolerances Diameter

A335 Pipe	Over	Under
NPS [DN]	in.	mm	in.	mm
1/8 to 1 1/2 / DN 6 to 40	1/64 (0.015)	0.4	1/64 (0.015)	0.4
Over 1 1/2 to 4 / DN 40 to 100	1/32 (0.031)	0.79	1/32 (0.031)	0.79
Over 4 to 8 / DN 100 to 200	1/16 (0.062)	1.59	1/32 (0.031)	0.79
Over 8 to 12 / DN 200 to 300	3/32 (0.093)	2.38	1/32 (0.031)	0.79
Over 12 / > DN 300	+/- 1% of the specified outside diameter

Wall Thickness

The tolerances in WT, in %, from specified are:

1/8 to 2 1/2 [6 to 65] incl., all t/D ratios: over 20%, under 12.5%

Above 2 1/2 [65], t/D < or = 5%: over 22.5%, under 12.5%

Above 2 1/2 [65], t/D > 5%: over 15%, under 12.5%

t = Specified Wall Thickness; D = Specified Outside Diameter)

Alloy Pipe Cross Reference Table Astm Vs. En Grades

Chrome Moly Pipes: Werkstoff vs EN vs ASTM
Werkstoff /DIN	EN	ASTM
1.5415	16Mo3	A335 Grade P1
1.7335	13CrMo4-5	A335 Grade P11, P12
1.7380	10CrMo9-10	A335 Grade P22
1.7362	X11CrMo5	A335 Grade P5
		A335 Grade P9
1.4903	X10CrMoVNb9-1	A335 Grade P91

A335/SA335 Alloy pipe in stock

A335 P22 Chrome Moly Alloy Seamless Pipe

A335 P9 Seamless Ferritic Alloy Steel Pipe

A335 P11 boiler tube for high temperature service

FAQ

What is ASTM a 335 material?

A335 seamless steel pipe is a type of alloy steel pipe, typically made from chromium-molybdenum alloy steel. This material gives the pipe excellent high-temperature and corrosion resistance, enabling it to perform stably in harsh environments for long periods. Common material grades include P5, P9, P11, etc., with different grades suitable for varying temperature and pressure conditions.