A335 PIPE SPECIFICATIONS

December 24, 2018

A335 PIPE SPECIFICATIONS

A/SA335

NPS 1/4″ – 24″

Schedules 40 through 160, STD, XH and XXH

Scope

This specification covers nominal wall and minimum wall seamless ferritic alloy-steel pipe intended for high-temperature service. ASTM A335 pipe ordered to this specification shall be suitable for fusion welding, bending, flanging (vanstoning), and similar forming operations.

Material & Manufacture

Pipe may be either hot finished or cold drawn with the finishing heat treatment noted below.

Heat Treatment Requirements

	P5, P9, P11, and P22
Grade	Heat Treatment Type	Normalizing Temperature Range F [C]	Subcritical Annealing or Tempering Temperature Range F [C]
	Heat Treatment Type	Normalizing Temperature Range F [C]	Subcritical Annealing or Tempering Temperature Range F [C]
P5 (b,c)	Full or Isothermal Anneal
	Normalize and Temper	*****	1250 [675]
	Subcritical Anneal (P5c only)	*****	1325 – 1375 [715 – 745]
P9	Full or Isothermal Anneal
	Normalize and Temper	*****	1250 [675]
P11	Full or Isothermal Anneal
	Normalize and Temper	*****	1200 [650]
P22	Full or Isothermal Anneal
	Normalize and Temper	*****	1250 [675]
P91	Normalize and Temper	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]
	Quench and Temper	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]

Chemical Requirements

	Grade	P-5	P-9	P-11	P-22	P-91	P-91 shall also include the following:
Element	UNS Designation	K41545	S50400	K11597	K21590	K91560	P-91 shall also include the following:
Carbon	0.15 max	0.15 max	0.05 – 0.15	0.05 – 0.15	0.08 – 0.12	V at 0.18 – 0.25
Manganese	0.30 – 0.60	0.30 – 0.60	0.30 – 0.60	0.30 – 0.60	0.30 – 0.60	N at 0.030 – 0.070
Phosphorous, max	0.025	0.025	0.025	0.025	0.020	Ni at 0.40 max
Sulfur, max	0.025	0.025	0.025	0.025	0.010	Al at 0.02 max
Silicon	0.50 max	0.25 – 1.00	0.50 – 1.00	0.50 max	0.20 -0.50	Cb at 0.06 – 0.10
Chromium	4.00 – 6.00	8.00 – 10.00	1.00 – 1.50	1.90 – 2.60	8.00 – 9.50	Ti at 0.01 max
Molybdenum	0.45 -0.65	0.90 – 1.10	0.44 – 0.65	0.87 – 1.13	0.85 – 1.05	Zr at 0.01 max

Tensile Requirements

		Seamless
		P-5	P-9	P-11	P-22	P-91	P91 shall not have a hardness not exceeding 250 HB/265 HV [25HRC].
Tensile Strength, min., psi
	ksi	60	60	60	60	85
	MPa	415	415	415	415	585
Yield Strength, min., psi
	ksi	30	30	30	30	60
	MPa	205	205	205	205	415

Permissible Variation in Wall Thickness

NPS [DN] Designator	Tolerance, % from Specified
		Over	Under
1/8 to 2 1/2 [6 to 65] incl., all t/D ratios		20.0%	12.5%
Above 2 1/2 [65], t/D < or = 5%		22.5%	12.5%
Above 2 1/2 [65], t/D > 5%		15.0%	12.5%
(t = Specified Wall Thickness; D = Specified Outside Diameter)

Elongation Requirements

Calculated Minimum Elongation Values
Elongation in 2 in. or 50 mm, min %
Wall Thickness		P5, P9, P11, P22		P91
in.	mm	Longitudinal	Transverse	Longitudinal
5/16 (0.312)	8	30	20	20
9/32 (0.281)	7.2	28	19	19
1/4 (0.250)	6.4	27	18	18
7/32 (0.219)	5.6	26		17
3/16 (0.188)	4.8	24		16
5/32 (0.156)	4	22		15
7/8 (0.125)	3.2	21		14
3/32 (0.094)	2.4	20		13
1/18 (0.062)	1.6	18		12

Permissible Variations in Outside Diameter

Outside Diameter at any point shall not vary from standard specified more than:

NPS [DN] Designator	Over		Under
	in.	mm	in.	mm
1/8 to 1 1/2 [6 to 40], incl.	1/64 (0.015)	0.40	1/64 (0.015)	0.40
Over 1 1/2 to 4 [40 to 100], incl.	1/32 (0.031)	0.79	1/32 (0.031)	0.79
Over 4 to 8 [100 to 200], incl.	1/16 (0.062)	1.59	1/32 (0.031)	0.79
Over 8 to 12 [200 to 300], incl.	3/32 (0.093)	2.38	1/32 (0.031)	0.79
Over 12 [300]	+/- 1% of the specified outside diameter

Mechanical Tests Specified

Transverse or Longitudinal Tension Test and Flattening Test, Hardness Test, or Bend Test
	For material heat treated in a batch-type furnace, tests shall be made on 5% of the pipe from each treated lot. For small lots, at least one pipe shall be tested.
	For material heat treated by the continuous process, tests shall be made on a sufficient number of pipe to constitute 5% of the lot, but in no case less than 2 pipe.
	Notes for Hardness Test:	P91 shall not have a hardness not exceeding 250 HB/265 HV [25HRC].
	Notes for Bend Test:	For pipe whose diameter exceeds NPS 25 and whose diameter to wall thickness ratio is 7.0 or less shall be subjected to the bend test instead of the flattening test.
		Other pipe whose diameter equals or exceeds NPS 10 may be given the bend test in place of the flattening test subject to the approval of the purchaser.
		The bend test specimens shall be bent at room temperature through 180 without cracking on the outside of the bent portion.
		The inside diameter of the bend shall be 1 inch [25 mm].
Hydrostatic Test		Each length of pipe shall be Hydro tested, at option of manufacture, nondestructive electric testing can be used.