Pressure & Wall Thickness Calculator ASME B31.3 Para. 304.1.2
Thickness from Pressure
Pressure from Thickness
Input Parameters
mm
MPa
°C
MPa
mm
ASME B31.3 Para. 304.1.2
Thickness from Pressure
t = ( P × D ) / ( 2 × (S×E + P×Y) ) + c
tmin = t / (1 - mill_tol)

// Reverse (MAWP from thickness)
P = 2SE(t-c) / (D - 2Y(t-c))
Variables
t = req. thickness (mm)  |  P = pressure (MPa)
D = outside diameter (mm)  |  S = allow. stress (MPa)
E = quality factor  |  Y = temp. coeff.  |  c = corrosion (mm)
Results
Fill in inputs and click Calculate.
🔘 Spectacle Blind / Line Blank Dimensions — ASME B16.48-2010
Metric (mm)
NPS Inside Dia. B (mm) Outside Dia. O (mm) Centerline A (mm) Thickness t (mm) Web Width W (mm)
📋 Pipe Schedule — ASME B36.10M (Carbon & Alloy Steel)
NPSOD (mm)Schedule Wall (mm)Wall (in)ID (mm) Weight (kg/m)
Elbow (LR)
Elbow (SR)
Elbow (3D)
Tee / Cross
Reducer
Cap
🔩 Long Radius Elbows — ASME B16.9-2018
📂 Allowable Stress — ASME B31.3 Table A-1 (MPa)
MaterialSpecGrade 20°C100°C150°C 200°C250°C300°C350°C400°C