Maximum Allowable Working Pressure for Steel Pipe

ASME B31.8-2022 – Tables 841.1.6, 841.1.7, 841.1.8

Design Parameters (ASME B31.8-2022)

Facility Type *

Location Class *

Design Factor (F): Not computed

Design Pressure (psi) *

Longitudinal Weld Joint Quality Factor (E) *

Joint Factor (E): Not selected

Temperature Derating Factor (T) *

Temp Factor (T): Not selected

MAWP Formula (ASME B31.8):
P = (2 × SMYS × F × E × T × t) / D

P = pressure (psi), SMYS (psi), F = design factor, E = joint factor, T = temp factor, t = wall thickness (in), D = outside diameter (in)

Design Factor (F)

Not computed

Joint Factor (E)

Not selected

Temp Factor (T)

Not selected

Design Pressure

Not specified

NPS 1/8" to 42" – ASME B31.8-2022

Grade A (30,000 psi)

Grade B (35,000 psi)

X42 (42,000 psi)

X52 (52,000 psi)

X60 (60,000 psi)

X65 (65,000 psi)

X70 (70,000 psi)

Meets design pressure

Does not meet design pressure

NPS (in)	Outside Diameter (in)	Schedule	Wall Thickness (in)	Grade A	Grade B	X42	X52	X60	X65	X70