Valve Flow Coefficient (Cv)
Solve the liquid sizing relation Q = Cv x sqrt(dP / SG) for Cv, flow, or pressure drop.
Example
You enter
- Solve for flow
- Fluid liquid
- Specific gravity 1
- Cv 10
- Pressure drop (psi) 25
You get
- Flow (GPM) 50
Checked against published worked examples from: ISA-75.01 / Crane TP-410 (control-valve sizing).
Details, formula, and sources
ScopeThe gas / compressible regime is flagged. Per ISA-75.01 / Crane TP-410.
Formula or tableLiquid: Q = Cv * sqrt(dP / SG), solved for Cv, flow Q (gpm), or pressure drop dP (psi). The gas / compressible regime uses a different (choked-aware) equation and is flagged, not computed.
Source and editionISA-75.01 / Crane Technical Paper 410 (TP-410) control-valve sizing relation, by name.
Free accessISA / Crane licensed; the incompressible liquid Cv relation is public and reproduced in valve-sizing references.
What governsEstimate. AHJ and licensed professional govern.
API field namessolve_for, fluid, specific_gravity, cv, dp_psi, flow_gpm
- Flow regime incompressible, non-choked liquid; specific gravity is relative to water at 60 FISA-75.01 / Crane TP-410