Valve Pressure Drop from Cv
Pressure a valve of known Cv eats at your flow — find out what that ball valve costs you.
Drop rises with flow SQUARED — a valve passing 2× the flow burns 4× the pressure. Cv data is on every valve datasheet; use it instead of guessing K.
Formula
Valve Pressure Drop from Cv is a free valve pressure drop for pump engineers, plumbers and plant designers — 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 Pressure Drop from Cv
Pressure a valve of known Cv eats at your flow — find out what that ball valve costs you. The calculation implements ΔP(psi) = SG·(Q/Cv)² (ISA-75.01.01). Drop rises with flow SQUARED — a valve passing 2× the flow burns 4× the pressure. Cv data is on every valve datasheet; use it instead of guessing K.
How to use Valve Pressure Drop from Cv
- 1Enter Valve Cv (US).
- 2Enter Flow in L/s.
- 3Enter Specific gravity.
- 4Read Pressure drop instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Valve Pressure Drop from Cv?
- ✓Implements the standard formula — ΔP(psi) = SG·(Q/Cv)²
- ✓Reference cited on-page: ISA-75.01.01
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Valve Pressure Drop from Cv use?+
It computes ΔP(psi) = SG·(Q/Cv)², per ISA-75.01.01. 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?+
Drop rises with flow SQUARED — a valve passing 2× the flow burns 4× the pressure. Cv data is on every valve datasheet; use it instead of guessing K.
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 Pressure Drop from Cv free to use?+
Yes — 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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