X20CrMoV11-1 / 1.4922 vs P91 / X10CrMoVNb9-1
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
X20CrMoV11-1 / 1.4922
Pipe & Tube Steel
X20CrMoV11-1 (1.4922) is the 12% chromium martensitic creep steel that carried European steam plant at 540–580 °C for decades before the 9Cr CSEF grades arrived. Huge installed base in turbines, valves and steam lines means it remains a steady maintenance and like-for-like replacement business.
Standards: DIN 1.4922 · AISI — (422 type, near)
P91 / X10CrMoVNb9-1
Pipe & Tube Steel
P91 is the 9Cr-1Mo-V-Nb creep-strength-enhanced ferritic steel that made modern ultra-supercritical power stations possible. Nitrogen and niobium carbonitrides hold its creep strength at 600 °C far beyond the older 2.25Cr and 12Cr grades, so main-steam pipework runs thinner and lighter.
Standards: DIN 1.4903 · AISI ASTM A335 P91 / A213 T91 · GB 10Cr9Mo1VNb (GB/T 5310)
Chemical composition compared (%)
| Element | X20CrMoV11-1 / 1.4922 | P91 / X10CrMoVNb9-1 |
|---|---|---|
| C | 0.17–0.24 | 0.08–0.12 |
| Si | ≤0.50 | 0.20–0.50 |
| Mn | ≤1.00 | 0.30–0.60 |
| P | ≤0.025 | ≤0.020 |
| S | ≤0.015 | ≤0.010 |
| Cr | 10.00–12.50 | 8.00–9.50 |
| Mo | 0.80–1.20 | 0.85–1.05 |
| V | 0.25–0.35 | 0.18–0.25 |
| Ni | 0.30–0.80 | ≤0.40 |
| Nb | — | 0.06–0.10 |
| N | — | 0.03–0.07 |
Properties compared
| Property | X20CrMoV11-1 / 1.4922 | P91 / X10CrMoVNb9-1 |
|---|---|---|
| Tensile strength | 800–950 MPa (quenched & tempered) | 585–760 MPa |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Creep service | Steam plant to ~580 °C — the pre-P91 generation | Power plant steam to ~600 °C |
| Yield strength | — | ≥415 MPa |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: X20CrMoV11-1 / 1.4922 · P91 / X10CrMoVNb9-1. Substitution decisions for certified parts stay with the design authority.