Alloy Steel P91 Pipes.
Seamless pipe to the specified material standard Supplied to ASTM A335 / ASME SA335 P91.
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Mill test certificate (EN 10204 3.1) supplied with material; third-party inspection on request.
Quick details
| Material grade | Alloy steel P91 (UNS K90901) |
|---|---|
| Standard | ASTM A335 / ASME SA335 P91 |
| Type | Seamless |
| Size range | 1/8" to 24" NB (6 to 600 DN); larger sizes on enquiry |
| Usage / application | Supercritical boiler headers, Main steam piping, Heat-recovery steam generators |
| Test certificate | Mill test certificate (EN 10204 3.1) supplied with material; third-party inspection on request. |
| Business type | Stockist and supplier |
| Location | 231/235, Sant Sena Maharaja Marg, Mumbai, Maharashtra 400004, India |
Also searched as: Alloy steel P91 pipe, Alloy steel P91 seamless pipe, ASTM A335 P91 pipe, UNS K90901 pipe, 1.4903 pipe
Product information for purchasing teams
P91 is a modified chromium-molybdenum alloy steel pipe grade specified under ASTM A335. Specify the required type, condition and design requirements, including the applicable welding and heat-treatment procedures. Wall thickness must follow the approved design.
Exact specification, availability and commercial details are confirmed against your enquiry.
Alloy Steel P91 Pipes specifications
| Material standard | ASTM A335 / ASME SA335 P91 |
|---|---|
| Grade | Alloy steel P91, UNS K90901, W.Nr 1.4903 |
| Size range | 1/8" to 24" NB (6 to 600 DN); larger sizes on enquiry |
| Schedules | Specify the required schedule or wall thickness against the applicable dimensional standard |
| Dimensional standards | ASME B36.10M, where specified by the order |
| Lengths | Single random, double random and cut-to-length |
| Ends | Plain, bevelled or threaded |
| Inspection | Third-party inspection on request |
| Documents | Mill test certificate (EN 10204 3.1) supplied with material; third-party inspection on request. |
Related designation references
| Grade | UNS | Werkstoff Nr. | EN / BS | JIS |
|---|---|---|---|---|
| Alloy steel P91 | K90901 | 1.4903 | X10CrMoVNb9-1 | STPA 28 |
Cross-standard references are not automatic substitutes. Confirm the exact product form, specification, composition, class and condition before accepting a substitution.
Chemical composition, %
| Grade | C | Mn | Si | P | S | Cr | Mo | V | Nb | N |
|---|---|---|---|---|---|---|---|---|---|---|
| Alloy steel P91 | 0.08 – 0.12 | 0.30 – 0.60 | 0.20 – 0.50 | ≤ 0.020 | ≤ 0.010 | 8.00 – 9.50 | 0.85 – 1.05 | 0.18 – 0.25 | 0.06 – 0.10 | 0.030 – 0.070 |
Mechanical properties
| Property | Value |
|---|---|
| Tensile strength | ≥ 585 MPa |
| Yield strength | ≥ 415 MPa |
| Elongation | ≥ 20% longitudinal |
| Hardness | 190 – 250 HB |
Values per ASTM A335 P91 Type 1. Confirm against the current edition of the standard and your purchase specification.
Density: 7.77 g/cm³
Types we supply
- Seamless
Applications
- Supercritical boiler headers
- Main steam piping
- Heat-recovery steam generators
- High-temperature refinery service
Questions buyers ask
Which standard covers Alloy Steel P91 Pipes?
Alloy Steel P91 Pipes are supplied to ASTM A335 / ASME SA335 P91.
What sizes of Alloy Steel P91 Pipes does Steel Impex India supply?
Size range: 1/8" to 24" NB (6 to 600 DN); larger sizes on enquiry. Schedules: Specify the required schedule or wall thickness against the applicable dimensional standard. Exact availability is confirmed for each enquiry.
Do Alloy Steel P91 Pipes come with a mill test certificate?
Mill test certificate (EN 10204 3.1) supplied with material; third-party inspection on request.
What should I send for the Alloy Steel P91 Pipes quotation?
Send grade, standard, dimensions, length, quantity and certificate requirements.
Where is Steel Impex India located?
Steel Impex India is at 231/235, Sant Sena Maharaja Marg, Mumbai, Maharashtra 400004, India We supply across India.