A335 P11 Pipe MAWP Calculator
ASTM A335 -P11 Alloy Steel Pipe SMLS 1 1/4Cr-1/2Mo-Si
Material Properties
Specification
A335 P11
Description
ASTM A335 -P11 Alloy Steel Pipe SMLS 1 1/4Cr-1/2Mo-Si
Tensile Strength
60 ksi
Yield Strength
30 ksi
B16.5 Flange Group
Group 1.9 — Alloy Steel 1¼Cr-½MoMin Design Temperature
-20 °F
Y Coefficient
Ref 3 — Ferritic steels
Calculator Settings
Custom Wall Thickness
Allowable Stress vs Temperature
Matching Flange Group
Group 1.9 — Alloy Steel 1¼Cr-½Mo(A182 F11 Cl.2, A217 WC6, A387-11)
Disclaimer: This calculator is for guidance only. Results are based on ASME B31.3-2024 allowable stresses for seamless pipe (Ej=1.0, W=1.0). Always verify against the current edition of the standard. The engineer of record is responsible for all design decisions.
References
- ASME B31.3-2024 — Process Piping, Table A-1
- ASME B36.10M — Welded and Seamless Wrought Steel Pipe
- ASME B16.5-2020 — Pipe Flanges and Flanged Fittings


