ASTM A335/ASME SA335
P91 Seamless Ferritic Alloy-Steel Pipe
ASTM A335/ASME SA335 P91 Seamless Ferritic Alloy-Steel Pipe
Short Description:
ASTM A335 Grade P91 Seamless Ferritic Alloy-Steel Pipes will be normalized at 1900°F [1040°C] minimum, and tempered at 1350°F [730°C] minimum as a final heat treatment.
Standard Specification for Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service
ASTM A335 P91 Seamless Ferritic Alloy-Steel Pipes cover nominal (average) wall seamless alloy-steel pipe intended for high-temperature service.
ASTM A335 P91 steel is an improved 9Cr-1Mo steel. When V, Nb and other alloy elements are added into the original 9Cr-1Mo martensitic steel, the allowable stress at 550-650 ℃ is significantly higher than that of 10CrMo910 and TP304 steel. Compared with 10CrMo910 steel, under the same temperature and pressure conditions, the pipe wall thickness can be reduced by 50%. The recommended use temperature of A335 P91 steel is below 650 ℃, A335 P91 steel has good high temperature resistance and resistance Corrosion and creep resistance,
ASTM A335 P91 Seamless Ferritic Alloy-Steel Pipe Quick Details
Manufacture:Seamless process ,Hot-finished or Cold-finished
Wall thickness(WT): 2.1mm——20 mm.
Outer diameter (OD): 21 mm——509mm
Common specifications:25mm*7mm, 141.3mm*6.55mm, 323.9mm*25.4mm,
Length: 6M or specified length as required.
Ends: Plain End, Beveled End, Threaded
Additional Info
Port of Shipment: Tianjin, China
Payment Terms:T/T, LC
Delivery: 7-15 days after payment
Surface: Tubes will be varnished (Outside only) to prevent rust.
Marking: Standard + Steel Grade + Size + Heat No + Lot No
Package: Bundles (hexagonal), Wooden Boxes, Crates (steel/wooden) or as required
Materials and Manufacture
Grade P91 Pipe may be either hot finished or cold drawn with the finishing treatment.
Heat Treatment:
Grade P91 Seamless Ferritic Alloy-Steel Pipes will be normalized at 1900°F [1040°C] minimum, and tempered at 1350°F [730°C] minimum as a final heat treatment.
Alternatively, liquid quenching and tempering is allowed for thicknesses above 3 in. when we mutually agreed with the purchaser.
Chemical Composition of ASTM A335 P91
| Grade | C | Mn | P | S | Si | Cr |
| A335 P91 | 0.08-0.12 | 0.3-0.6 | ≤0.02 | ≤0.01 | 0.2-0.5 | 8.0-9.5 |
| Mo | V | N | Ni | Al | Nb | |
| 0.85-1.05 | 0.18-0.25 | 0.03-0.07 | ≤0.4 | ≤0.04 | 0.06-0.10 |
Mechanical Properties of ASTM A335 P91
| Grade | Mechanical property | ||
| Tensile Strength(MPa) | Yield Strength(MPa) | Elongation(%) | |
| P91 | ≥510 | ≥400 | ≥20 |
Outside diameter tolerances of ASTM A335 Seamless Ferritic Alloy-Steel Pipe
| NPS Designator | Over | Under | ||
| in. | mm | in. | mm | |
| 1⁄8 to 1 1⁄2 , incl. | 1 ⁄ 64 (0.015) | 0.40 | 1 ⁄ 64 (0.015) | 0.40 |
| Over 1 1⁄2 to 4, incl. | 1 ⁄ 32 (0.031) | 0.79 | 1 ⁄ 32 (0.031) | 0.79 |
| Over 4 to 8, incl. | 1 ⁄ 16 (0.062) | 1.59 | 1 ⁄ 32 (0.031) | 0.79 |
| Over 8 to 12, incl. | 3 ⁄ 32 (0.093) | 2.38 | 1 ⁄ 32 (0.031) | 0.79 |
| Over 12 | ± 1 % | |||
Hydrostatic Test
Each length of pipe shall be subjected to the hydrostatic test or nondestructive examination.
Mechanical Tests Required
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 1 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.
Marking
In addition to the marking prescribed in Specification A 999/A 999M, the marking shall include the length, the ANSI schedule number and the heat number or manufacturer’s number by which the heat can be identified.
Photos of ASTM A335 P91 Seamless Ferritic Alloy-Steel Pipe
Note: Material furnished under ASTM A335 conform to the applicable requirements of the current edition of Specification A 999/A 999M