Ball Valves - Flow Coefficients Cv
A conventional ball valve is normally not used as a throttling valve since a partial flow will create high velocity flow tear at the ball and the seal.
Full Bore Valves
Typical flow coefficients - Cv - for full bore valves:
For full table - rotate the screen!
| Valve Size | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| inches | 1/2 | 3/4 | 1 | 1 1/2 | 2 | 2 1/2 | 3 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 |
| mm | 12 | 19 | 25 | 37.5 | 50 | 62.5 | 75 | 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 |
| Flow Coefficient Cv |
26 | 50 | 94 | 260 | 480 | 750 | 1300 | 2300 | 5400 | 10000 | 16000 | 24000 | 31400 | 43000 | 57000 |
Reduced Bore Valves
Typical flow coefficients - Cv - for reduced bore valves:
For full table - rotate the screen!
| Valve Size | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| inches | 3 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 |
| mm | 75 | 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 |
| Flow Coefficient Cv |
420 | 770 | 1800 | 2500 | 4500 | 8000 | 12000 | 14000 | 18000 | 22000 |
These values are suitable for estimates only. Since the bore in valves varies the valve manufacturer should always be consulted for the actual Cv for the valve selected.
Related Topics
• Control Valve Sizing
Control Valve terminology, bodies, trim, flow characteristics, Cv and Kv sizing, noise, actuators, positioners and more.
• Piping Systems
Calculate dimensions of pipes and tubes. Pressure drop calculations and head loss charts. Use of different piping materials. Insulation of pipes and tubes and heat loss diagrams.
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