Look at flow coefficient, cylinder bore, and rod speed to best match pneumatic actuators and valves.
Assuming 80 psig for inlet pressure based on a typical plant operating at 100 psig with line losses and using a conservative 5-psi pressure drop for the constant A, chart average cylinder rod speed versus cylinder diameter in terms of required Cv. The accompanying tables for two and threeposition valves highlight areas where each ISO valve meets Cv requirements.
d = Cylinder diameter, in.
G = Specific gravity of the fluid (G = 1 for air)
l = Cylinder length, in.
P1= Absolute pressure at inlet port (gage pressure + 14.7), psi
P2 = Absolute pressure at outlet port, psi
Pa = Atmospheric pressure, psi
Q = Volumetric flow rate, scfm
T = Absolute temperature of air, °R
t = Time to fill cylinder, sec
V = Cylinder volume, in.3