ASTM A335 P22 alloy steel pipe

ASTM A335 Chrome Moly Pipe

ASTM A335 Pipe (ASME S/A335, Chorme-Moly) is a seamless ferritic Alloy-Steel Pipe for high temperature service. Pipe ordered to this specification shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding. Sometimes referred to as “P Grade”, chome moly pipe is popular in P-Grades P5, P9, P11, P22, and P91.

ASTM A335 P11 alloy steel pipe

ASTM A335 P11 is the part of ASTM A335, the pipe shall be suitable for bending, flanging, and similar forming operations, and for fusion welding.

ASTM A335 P22 steel pipe

A335 is often called chrome moly pipe because of the chemical makeup of Molybdenum (Mo) and Chromium (Cr).

ASTM A335 P91 high pressure pipe

ASTM A335 P91 High pressure boiler pipesASTM A335 P91 high pressure seamless boiler pipe shall be suitable for bending, flanging, and similar forming operations, and for fusion welding.

ASTM A335 P5 High pressure boiler pipes

The range of ASTM A335 P5 pipe sizes that may be examined by each method shall be subjected to the limitations in the scope of the respective practice.

ASTM A335 P9 alloy steel pipe

ASTM A335 P9 Alloy steel pipe apply to petroleum, chemical industry, electric power, boiler, high temperature resistant, low temperature resistant, corrosion resistant.

ASTM A335 P92 High pressure boiler pipes

ASTM A335 P92 is the part of ASTM A335, The pipe shall be suitable for bending, flanging, and similar forming operations, and for fusion welding.

A335 is often called chrome moly pipe because of the chemical makeup of Molybdenum (Mo) and Chromium (Cr). Molybdenum increases the strength of steel as well as the elastic limit, resistance to wear, impact qualities, and hardenability. Moly increases the resistance to softening, restrains grain growth and makes chromium steel less susceptible to embrittlement. Moly is the most effective single additive that increases high temperature creep strength.It also enhances the corrosion resistance of steel, and inhibits pitting. Chromium (or chrome) is the essential constituent of stainless steel. Any steel with 12% or more Chrome is considered stainless. Chrome is virtually irreplaceable in resisting oxidation at elevated temperatures. Chrome raises the tensile, yield, and hardness at room temperatures. The composition chrome moly alloy steel pipe make it ideal for use in power plants, refineries, petro chemical plants, and oil field services where fluids and gases are transported at extremely high temperatures and pressures.

Chemical Composition:
Grade  C  Mn  P  S  Si  Mo
 P1  0.10-0.20  0.30-0.80  0.025  0.025  0.10-0.50  0.44-0.65
 P2  0.10-0.20  0.30-0.61  0.025  0.025  0.10-0.30  0.44-0.65
 P5  0.15max  0.30-0.60  0.025  0.025  0.50max  0.45-0.65
 P5b  0.15max  0.30-0.60  0.025  0.025  1.00-2.00  0.45-0.65
 P5c  0.12max  0.30-0.60  0.025  0.025  0.50max  0.45-0.65
 P9  0.15max  0.30-0.60  0.025  0.025  0.25-1.00  0.90-1.10
 P11  0.05-0.15  0.30-0.60  0.025  0.025  0.50-1.00  0.44-0.65
 P12  0.05-0.15  0.30-0.61  0.025  0.025  0.50max  0.44-0.65
 P15  0.05-0.15  0.30-0.60  0.025  0.025  1.15-1.65  0.44-0.65
 P21  0.05-0.15  0.30-0.60  0.025  0.025  0.50max  0.80-1.06
 P22  0.05-0.15  0.30-0.60  0.025  0.025  0.50max  0.87-1.13
 P23  0.04-0.10  0.10-0.60  0.030max  0.010max  0.50max  0.05-1.30
Mechanical Properties
Mechanical properties  P1,P2  P12  P23  P91  P92,P11  P122
 Tensile strength  380  415  510  585  620  620
 Yield strength  205  220  400  415  440  400
Heat Treatment
A / N+T
N+T / Q+T
N+T
Material & Manufacture

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

Heat Treatment Requirements
Grade Heat Treatment Type
P5, P9, P11, and P22
Normalizing Temperature Range F [C] Subcritical Annealing or Tempering
Temperature Range F [C]
A335 P5 (b,c) Full or Isothermal Anneal
Normalize and Temper ***** 1250 [675]
Subcritical Anneal (P5c only) ***** 1325 – 1375 [715 – 745]
A335 P9 Full or Isothermal Anneal
Normalize and Temper ***** 1250 [675]
A335 P11 Full or Isothermal Anneal
Normalize and Temper ***** 1200 [650]
A335 P22 Full or Isothermal Anneal
Normalize and Temper ***** 1250 [675]
A335 P91 Normalize and Temper 1900-1975 [1040 – 1080] 1350-1470 [730 – 800]
Quench and Temper 1900-1975 [1040 – 1080] 1350-1470 [730 – 800]
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.

Hydrostatic Test

The inside diameter of the bend shall be 1 inch [25 mm].
Each length of pipe shall be Hydro tested, at option of manufacture nondestructive electric testing can be used.

Ordering Information

Orders for material under this specification should include the following, as required, to describe the desired material adequately:

Quantity Feet, meters, or number of lengths
Name of material Seamless Alloy Steel Pipe
Grade P5, P9, P11, P22, P91
Manufacture Hot-finished or cold-drawn
Size using one of the following:
NPS and Schedule Number
Outside Diameter and Nominal Wall Thickness
Outside Diameter and Minimum Wall Thickness
Inside Diameter and Nominal Wall Thickness
Inside Diameter and Minimum Wall Thickness
Length Specific or Random
End Finish
Download A335 Specification

downalod-pdfAstm A335 standard specication for seamless ferritic alloy-steel pipe for high-temperature service

Referenced Documents
  • A999/A999M Specification for General Requirements for Alloy and Stainless Steel Pipe
  • E213 Practice for Ultrasonic Examination of Metal Pipe and Tubing
  • E309 Practice for Eddy-Current Examination of Steel Tubular Products Using Magnetic Saturation
  • E381 Method of Macroetch Testing Steel Bars, Billets, Blooms, and Forgings
  • E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
  • E570 Practice for Flux Leakage Examination of Ferromagnetic Steel Tubular Products
  • B36.10M Welded and Seamless Wrought Steel Pipe
  • SAE J 1086 Practice for Numbering Metals and Alloys (UNS)
  • SNT-TC-1A Recommended Practice for Nondestructive Personnel Qualification and Certification