🔩 ASME B16.5 Flange P-T Rating
Compute maximum allowable pressure for flanges at design temperature. Supports Class 150–2500, material groups 1.1–2.2, and gasket factor lookup per ASME B16.20.
📝 Configuration
P_max = P_150(T) × Class_Factor × Material_Factor
Gasket: m, y per ASME B16.20
📊 Results
Configure inputs and click Compute to view results.
📘 Methodology
ASME B16.5 Ratings
Pressure-temperature ratings define the maximum allowable working pressure at a given temperature for each class. The base table is for Class 150, Group 1.1 material, and higher classes are scaled by standardized factors (e.g., Class 300 = 2.63× Class 150).
Material Groups
Materials are grouped by composition and strength. Group 1.1 (carbon steel A105) is the reference. Austenitic stainless steels (Groups 2.1/2.2) have different high-temperature behavior. Material factors adjust the base rating accordingly.
Gasket Factors
ASME B16.20 defines gasket factor m (maintenance factor) and minimum seating stress y (psi). Higher m and y values indicate a tighter, more reliable seal but require greater bolt loads. Spiral wound (m=3.0) is the most common industrial gasket.