CV Flow Calculator

What Is the Cv Flow Coefficient?

Cv is the flow coefficient of a valve — the gallons per minute (GPM) of water at 60°F that flows through a fully open valve with a 1 psi pressure drop. It sizes control valves for liquid service.

Cv Flow Formula

\(Q\) is volumetric flow in GPM, \(\Delta P\) is pressure drop in psi, and \(SG\) is specific gravity relative to water. For water at room temperature, \(SG = 1\).

Example: Cv = 10 with 100 psi drop and SG = 1 gives \(Q = 10 \times \sqrt{100} = 100\) GPM.

Applications

Cv sizing is used in process control, HVAC hydraulics, chemical plant valve selection, and piping design where pressure drop and flow rate must be matched to valve capacity.