Valve Cv Flow Calculator
Flow through a valve of known Cv at a given pressure drop (liquid service).
Kv (metric) = 0.865 ร Cv. Control valves should take 25โ50% of system drop at design flow or they can't control.
Formula
Valve Cv Flow Calculator is a free cv flow for pump engineers, plumbers and plant designers โ instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Valve Cv Flow Calculator
Flow through a valve of known Cv at a given pressure drop (liquid service). The calculation implements Q(gpm) = Cvยทโ(ฮP(psi)/SG) (ISA-75.01.01 โ control valve sizing equations). Kv (metric) = 0.865 ร Cv. Control valves should take 25โ50% of system drop at design flow or they can't control.
How to use Valve Cv Flow Calculator
- 1Enter Valve Cv (US) (Cv = gpm at 1 psi ฮP, water).
- 2Enter Pressure drop in kPa.
- 3Enter Specific gravity.
- 4Read Flow, Flow instantly โ no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Valve Cv Flow Calculator?
- โImplements the standard formula โ Q(gpm) = Cvยทโ(ฮP(psi)/SG)
- โReference cited on-page: ISA-75.01.01 โ control valve sizing equations
- โOne-click SI โ Imperial toggle โ values convert in place, physics stays in SI
- โLive worked example: the substitution recomputes from your numbers
- โRuns entirely in your browser โ nothing uploaded, free forever
Frequently asked questions
What formula does the Valve Cv Flow Calculator use?+
It computes Q(gpm) = Cvยทโ(ฮP(psi)/SG), per ISA-75.01.01 โ control valve sizing equations. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Kv (metric) = 0.865 ร Cv. Control valves should take 25โ50% of system drop at design flow or they can't control.
Can I use this for pump selection?+
Use it to establish the duty (flow, head, NPSH, power) and then pick a pump whose curve passes through that point near best efficiency. The tool gives you the engineering numbers a supplier will ask for.
Is the Valve Cv Flow Calculator free to use?+
Yes โ completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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