Issuing body
ASTM
Latest edition
A335/A335M-22
Region
USA, Global
Equipment items
1
Scope
Cr-Mo alloy steel pipe (P11, P22, P91, etc.) for elevated-temperature service.
Key requirements (7)
- Seamless ferritic alloy-steel pipe for high-temperature service.
- Grades: P5, P9, P11, P12, P22, P91, P92 (Cr-Mo content varies).
- P22 (2.25Cr-1Mo): widely used in refineries, power plants up to ~600 °C.
- P91 (9Cr-1Mo-V): high-temp creep resistance up to ~625 °C; mandatory PWHT.
- Heat treatment: normalized + tempered (or Q&T for some grades).
- Welding consumables matched to base metal (e.g., E9018-B3 for P22).
- Used for boiler tubes, superheaters, reheaters, hydrogen reformers.
Related standards (1)
Applied to 1 equipment item
Piping & Fittings