Cv Flow Calculator
Get Cv from Q (gpm), ΔP (psi), and specific gravity (SG).
How to Use This Calculator
- Enter liquid flow Q in gpm.
- Enter pressure drop ΔP across the valve in psi.
- Enter specific gravity SG relative to water.
- Click Calculate to get Cv.
Formula
Q = Cv · √(ΔP / SG)
Rearranged: Cv = Q / √(ΔP/SG). Valid for incompressible liquids under standard conditions.
Frequently Asked Questions
What about gases?
Gas sizing uses different relations (choked/unchoked flow). This tool is for liquids.
Units?
This standard definition assumes Q in gpm and ΔP in psi. SG is unitless.