What is Control Valve Cv and Why is it Important? If you work in Instrumentation, Process Control, or Industrial Automation, understanding Control Valve Cv (Flow Coefficient) is essential. Cv represents the amount of water (in US gallons per minute) that flows through a fully open valve with a 1 psi pressure drop at 60°F. It helps engineers select the correct control valve for the required flow conditions. For liquid flow, the formula is: Q = Cv × √(ΔP / SG) Where: Q = Flow Rate Cv = Flow Coefficient ΔP = Pressure Drop Across the Valve SG = Specific Gravity of the Fluid A higher Cv means the valve can pass more flow, while the pressure drop and fluid properties also affect the final flow rate. Correct Cv selection improves process stability, control accuracy, energy efficiency, and valve life. Post navigation PSI vs BAR – Do You Know the Difference?
