ASTM A335 Grade P91 Alloy Steel Seamless Pipes

Hebei Zhongji Is A Global Leading Supplier For Your A335 P91 Alloy Steel Seamless Pipes Needs.

SA/A335 P91 seamless pipe is a kind of chrome moly pipes (ASME S/A335, Chrome-Moly) listed in ASTM A335, which has become a standard in the power generation industry and the petrochemical industry, not only because of its tensile strength, corrosion resistance and high-temperature strength, but also because of its cost-effectiveness. Chrome Moly Pipes are popular in P-Grades P5, P9, P11, P22, P91 and P92. The most common use of grades P11, P22 and P91 is in the powder industry and petrochemical plants, Grades P5 and P9 are commonly used in refineries. 

We stock a full range of the following A335 Chrome Moly Pipe grades

SA/A335 P91 Seamless Pipes Sizes

1/4” Nominal to 24”O.D. Seamless Alloy Pipe
Wall Thickness – Schedule 40 through XXH

Chrome Moly Pipe Specifications & Grades

SA335 & A335 – Grades P5, P9, P11, P22, P91, P92
A691 1-1/4 Chrome through 9 Chrome (Welded Alternative to A335)

SA/A335 P91 Seamless Pipe Specifications

A/SA335

NPS 1/4″ – 24″

Schedules 40 through 160, STD, XH and XXH 

SA/A335 P91 Seamless Pipe Dimensions

SA/A335 P91 Seamless Pipe Weight

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.

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Material & Manufacture

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

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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]
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]

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SA/A335 P91 Seamless Pipe 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
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

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SA/A335 P91 Seamless Pipe Mechanical Properties

		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

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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)

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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

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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

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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.

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