Ball Valves

The below CV values are used to give an indication of flow rates for ball valves. CV value is an imperial measure of flow in US gallons per minute of water at 60° fahrenheit with a pressure drop of 1 psi across the valve. This is used as a guide and is not a linear progression.

V Port Ball Valves Flow Rate (CV)

Valve Size Ball Angle 15% 20% 30% 40% 50% 60% 70% 80% 90% 100%
1/2" 30°* 0.1 0.1 0.2 0.3 0.5 0.8 1.1 1.6 2.2 2.6
60° 0.1 0.1 0.3 0.5 0.9 1.4 2 3.3 4.4 6
3/4" 30°* 0.1 0.2 0.5 0.7 1.1 1.8 2.4 3.3 4.5 5.4
60° 0.1 0.2 0.7 1 1.7 2.8 4 6.5 9 12
1" 30°* 0.1 0.3 0.8 1.3 2.3 3.5 5.1 9.8 8.5 10
60° 0.2 0.4 1.1 1.8 3.4 5.3 7.9 12.3 15.3 21
1 1/4" 30°* 0.2 0.4 1.1 2 3.7 5.5 8 10 13 15
60° 0.2 0.6 1.8 3 5.5 9.5 12.8 19 26 39
1 1/2" 30°* 0.3 0.6 1.6 3 5 7.5 11 14 17 20
60° 0.4 0.8 2.5 4 8 13 19 27 40 52
2" 30°* 0.4 1.2 3.8 6 10 15 23 31 43 60
60° 0.4 1.5 4.6 9 16.5 27 39 55 83 110
2 1/2" 30°* 0.4 1 4 8 12 18 28 37 62 75
60° 0.4 1.5 5 10 21 34 53 75 103 150
3" 30°* 0.5 1.2 4 8 14 23 33 46 65 82
60° 0.5 2.5 6 14 25 40 65 91 128 165
4" 30°* 0.6 2 6 15 29 48 71 100 130 159
60° 0.7 3 11 25 40 59 90 141 212 356
6" 30°* 0.9 3.2 14 33 60 103 155 220 280 350
60° 2 5 22 60 110 190 285 416 586 800

* 60° Balls as standard with 30° Ball by special order


Flow Rate for two way Full Bore ball valves (CV)

Size BSP DN (mm) CV when fully open
¼” 8 18
⅜” 10 20
½” 15 23
¾” 20 55
1” 25 95
1 ¼” 32 155
1 ½” 40 260
2” 50 440
2 ½” 65 710
3” 80 1050
4” 100 2040
 

3 Way Reduced Port Threaded Ball Valves

Size Cv Kv (m3/h)
1/4" 12.8 11
3/8" 12.8 11
1/2" 15.2 13
3/4" 17.5 15
1" 36.2 31
1-1/4" 45.5 39
1-1/2" 72.4 62
2" 120.2 103
2-1/2" 239.2 205
3" 270.7 232
4" 480.8 412

3 Way Full Bore Flanged Ball Valves

Size Cv Kv (m3/h)
1/2" 15.2 13
3/4" 23.3 20
1" 45.5 39
1-1/4" 58.4 50
1-1/2" 112 96
2" 224.1 192
2-1/2" 308.1 264
3" 409.6 351
4" 762.1 653