Gas Flow Calculation W = KCAP (ASME VIII) Steam Flow Calculation  W = 51.5 KAP    (ASME VIII) Liquid Flow Calculation  Q = 22.8  (Crane No. 410) Where W = Flow, Lb/hr Q = Flow, GPM K = Coefficient of discharge    = .62 Per ASME UG 127(a) (2) (a) unless flow test data available A = actual discharge area, sq. in (See table based on nominal Rupture Disk size) P = (Set pressure x 1.10) + 14.7 = psia M = Molecular weight (use 29 for air) Z = Compressibility factor (use 1 for air) T = Absolute temperature, oF + 460 Δ P  = Set pressure x 1.10 S = Specific gravity of liquid C = Constant based on ratio of specific heats (use 356 for air) C = 520 Solving these equations for A will give the required Rupture Disk discharge area. Then select the required nominal Disk size from the table.