Flow Coefficient, Opening and Closure Curves of Full Bore Ball Valves

Flow Coefficient, Opening and Closure Curves of Full Bore Ball Valves

Flow Coefficient and Flow Factor Values

The table below list typical maximum flow coefficient, Cv, and flow factor, Kv, values for full bore ball valves:

Nominal Diameter Max Cv Max Kv
Inch mm gpm.psi (m³/hr).bar
1″ 25 90 78
2″ 50 470 407
3″ 80 1200 1038
4″ 100 2500 2163
6″ 150 5600 4844
8″ 200 10000 8650
10″ 250 16000 13840
12″ 300 23000 19895
14″ 350 31300 27075
16″ 400 41000 35465
18″ 450 52000 44980
20″ 500 65000 56225
24″ 600 94000 81310
26″ 650 110000 95150
28″ 700 128000 110720
30″ 750 147000 127155
32″ 800 167000 144455
36″ 900 211000 182515
40″ 1000 261000 225765
42″ 1050 288000 249120
48″ 1200 376000 325240

Cv & Kv Fraction vs Angle Closure Curve Chart

This graph shows the Cv or Kv valve fraction vs opening and closing angle of a full bore ball valve:

Full Bore Ball Cv Fraction

The full closure curve of a ball valve is then the above graph multiplied by the valve’s flow coefficient or factor.

Cv vs Angle Closure Curve Values Table

The tables below list the full Cv vs angle closure and opening curves for various valve diameters:

 

Full Bore Ball Valve Cv vs Angle for Different Diamters
  1″ 2″ 3″ 4″
0° 0 0 0 0
10° 3 15 39 81
20° 5 27 68 142
30° 9 45 116 242
40° 15 76 193 403
50° 23 118 300 625
60° 35 180 460 958
70° 58 301 768 1600
80° 77 404 1032 2150
90° 90 470 1200 2500
         
  6″ 8″ 10″ 12″
0° 0 0 0 0
10° 180 322 516 741
20° 317 567 907 1303
30° 541 967 1547 2223
40° 902 1611 2578 3706
50° 1400 2500 4000 5750
60° 2147 3833 6133 8817
70° 3584 6400 10240 14720
80° 4816 8600 13760 19780
90° 5600 10000 16000 23000
         
14″ 16″ 18″ 20″
0° 0 0 0 0
10° 1009 1321 1676 2094
20° 1774 2323 2947 3683
30° 3026 3963 5027 6283
40° 5043 6606 8378 10472
50° 7825 10250 13000 16250
60° 11998 15717 19933 24917
70° 20032 26240 33280 41600
80° 26918 35260 44720 55900
90° 31300 41000 52000 65000
         
24″ 26″ 28″ 30″
0° 0 0 0 0
10° 3029 3544 4124 4737
20° 5327 6233 7253 8330
30° 9087 10633 12373 14210
40° 15144 17722 20622 23683
50° 23500 27500 32000 36750
60° 36033 42167 49067 56350
70° 60160 70400 81920 94080
80° 80840 94600 110080 126420
90° 94000 110000 128000 147000
         
32″ 36″ 40″ 42″
0° 0 0 0 0
10° 5381 6799 8410 9280
20° 9463 11957 14790 16320
30° 16143 20397 25230 27840
40° 26906 33994 42050 46400
50° 41750 52750 65250 72000
60° 64017 80883 100050 110400
70° 106880 135040 167040 184320
80° 143620 181460 224460 247680
90° 167000 211000 261000 288000
         
48″
0° 0
10° 12116
20° 21307
30° 36347
40° 60578
50° 94000
60° 144133
70° 240640
80° 323360
90° 376000

 

Kv vs Angle Closure Curve Values Table

The tables below list the full Kv vs angle closure and opening curves for various metric valve diameters:

Ball Valve Kv vs Angle for Different Diameters
(mm) 25 50 75 100
0° 0 0 0 0
10° 3 13 33 70
20° 4 23 59 123
30° 8 39 100 209
40° 13 65 167 348
50° 19 102 260 541
60° 30 156 398 829
70° 50 260 664 1384
80° 67 350 893 1860
90° 78 407 1038 2163
         
(mm) 150 200 250 300
0° 0 0 0 0
10° 156 279 446 641
20° 274 490 784 1127
30° 468 836 1338 1923
40° 780 1394 2230 3205
50° 1211 2163 3460 4974
60° 1857 3316 5305 7626
70° 3100 5536 8858 12733
80° 4166 7439 11902 17110
90° 4844 8650 13840 19895
         
(mm) 350 400 450 500
0° 0 0 0 0
10° 872 1143 1449 1812
20° 1534 2010 2549 3186
30° 2617 3428 4348 5435
40° 4362 5714 7247 9058
50° 6769 8866 11245 14056
60° 10379 13595 17242 21553
70° 17328 22698 28787 35984
80° 23284 30500 38683 48354
90° 27075 35465 44980 56225
         
(mm) 600 650 700 750
0° 0 0 0 0
10° 2620 3066 3568 4097
20° 4608 5392 6274 7205
30° 7860 9198 10703 12292
40° 13100 15330 17838 20486
50° 20328 23788 27680 31789
60° 31169 36474 42443 48743
70° 52038 60896 70861 81379
80° 69927 81829 95219 109353
90° 81310 95150 110720 127155
         
(mm) 800 900 1000 1050
0° 0 0 0 0
10° 4655 5881 7275 8027
20° 8186 10343 12793 14117
30° 13964 17643 21824 24082
40° 23273 29405 36373 40136
50° 36114 45629 56441 62280
60° 55374 69964 86543 95496
70° 92451 116810 144490 159437
80° 124231 156963 194158 214243
90° 144455 182515 225765 249120
         
(mm) 1200
0° 0
10° 10480
20° 18430
30° 31440
40° 52400
50° 81310
60° 124675
70° 208154
80° 279706
90° 325240

See Also