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Ball Valves - Flow Coefficients Cv

Flow coefficients - Cv - for typical ball valves - reduced and full bore.

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 - C_v - for full bore valves:

For full table - rotate the screen!

Typical flow coefficients - *C_v -* for full bore valves
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 C_v	26	50	94	260	480	750	1300	2300	5400	10000	16000	24000	31400	43000	57000

Reduced Bore Valves

Typical flow coefficients - C_v - for reduced bore valves:

For full table - rotate the screen!

Typical flow coefficients - *C_v -* for reduced bore valves
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 C_v	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 C_v for the valve selected.

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