Control Valve What is Valve Rangeability ?
Rangeability is the ratio of maximum controllable flow to minimum controllable flow
For the control valve selection rangeability is one of the important selection factor.
Minimum and Maximum Cv of Valves are calculated .If the ratio of Cv Maximum to Cv Minimum is within the rangeability of the selected control valve ,the valve should function properly
Cv - Flow Coefficient
To know more about Control Valve sizing read the article