Forged flanges & fittings
ASTM A182 F304H — chemistry & properties
ASTM A182 F304H (Forged flanges & fittings, UNS S30409): chemical composition and mechanical properties. High-temperature service above about 525 °C — superheater headers, refinery heaters
Chemical composition (wt %)
| C | 0.04 – 0.1 |
| Mn | ≤ 2 |
| P | ≤ 0.045 |
| S | ≤ 0.03 |
| Si | ≤ 1 |
| Cr | 18 – 20 |
| Ni | 8 – 11 |
Mechanical properties
| Tensile strength, min | 515 MPa |
| Yield strength, min | 205 MPa |
| Elongation, min | 30 % |
| Hardness | Not specified |