WP11 (1¼Cr-½Mo, Grade 11) is the intermediate chrome-moly grade — the workhorse of boiler and steam line piping for moderate elevated temperature service. Excellent balance of strength, toughness, and...
WP11 (1¼Cr-½Mo, Grade 11) is the intermediate chrome-moly grade — the workhorse of boiler and steam line piping for moderate elevated temperature service. Excellent balance of strength, toughness, and weldability. Less demanding PWHT requirements than WP22 and WP91. Widely specified for boiler superheaters, steam headers, and main steam lines in subcritical power plants.
| Property | Value |
|---|---|
| Grade | WP11 (P11) |
| ASTM / ASME | ASTM A234 WP11 Cl.1 / Cl.3 |
| UNS Number | — |
| Chromium (Cr) | 1.0–1.5% |
| Nickel (Ni) | ≤0.30% |
| Molybdenum (Mo) | 0.44–0.65% |
| Max/Min Service Temp | 550°C |
| Fitting Standard | ASME B16.9 / MSS SP-43 |
| Size Range | ½" NB to 48" NB |
| Certificate | EN 10204 3.1 MTC |
Send type, size, schedule, quantity, standard. We respond within 4 hours with pricing and availability.