Control Valve · Glossary
What is Kv Flow Factor?
Symbol: Kvm³/h at 1 barControl Valve
Kv flow factor is the flow of water in m³/h through a valve with a pressure drop of 1 bar; it is the metric version of Cv.
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Kv Flow Factor Explained
Kv is used in Europe and in IEC standards. It is converted to Cv by multiplying by 1.156.
The same corrections for viscosity, piping and choked flow apply as for Cv.
Kv Flow Factor Formula
Kv = Q × √(SG ÷ ΔP)
| Q | flow (m³/h) |
| SG | specific gravity, water = 1 |
| ΔP | pressure drop (bar) |
Example: 50 m³/h of water at 1 bar drop: Kv = 50, so Cv ≈ 57.8.
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Calculators for Kv Flow Factor
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Frequently Asked Questions
What is Kv Flow Factor?
Kv flow factor is the flow of water in m³/h through a valve with a pressure drop of 1 bar; it is the metric version of Cv.
Is Kvs the same as Kv?
Kvs is the Kv at full rated travel, the catalogue value.
Why do Kv and Cv differ by 1.156?
The units differ: m³/h and bar against US gpm and psi.
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