Valve Coefficient Tables

Select a product line below to view valve coefficients.

For reference only
Pressure Regulator - Pilot Operated and Spring Loaded
Regulator Type Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Pilot Operated Regulator

Pilot Operated *
Equal Percentage 1 1/2 0.75 0.4 0.7 0.9 1.3 1.8 2.5 3.2 3.9 4.5 5
Equal Percentage 1 1 0.74 1.1 1.8 2.4 3.4 4.8 6.6 8.5 10.2 11.9 13.2
Equal Percentage 2 1 1/4 0.75 1.8 2.8 3.9 5.4 7.7 10.5 13.6 16.2 19 21
Equal Percentage 2 2** 0.84 4 6.2 8.6 12.1 17.2 23.5 30.4 36.3 42.5 47
Equal Percentage 2 2 0.75 4.4 6.9 9.5 13.4 19.1 26 33.6 40.2 47 52
Equal Percentage 3 1 5/8 0.82 2.9 4.5 6.2 8.8 12.5 17 22 26.3 30.7 34
Equal Percentage 3 3 0.75 9.9 15.6 21.5 30.2 42.9 58.6 75.7 90.4 105.7 117
Equal Percentage 4 2 0.80 4.7 7.3 10.1 14.2 20.2 27.5 35.6 42.5 49.7 55
Equal Percentage 4 4 0.75 17.8 27.9 38.6 54.2 77 105.2 135.9 162.2 189.8 210
Equal Percentage 6 3 0.80 10.2 16 22 30.9 44 60.1 77.7 92.7 108.4 120
Equal Percentage 6 6 0.75 40.6 63.8 88.1 123.8 176 240.4 310.6 370.7 433.7 480
 

Spring Loaded Regulator

Spring-Loaded Back Pressure
Equal Percentage 2 1 1/4 0.84 1.3 2.4 4 6.7 10.4 14.4 16.9 19.7 22.1 24
Equal Percentage 2 2 0.75 4 6.2 8.6 12.1 17.2 23.5 30.4 36.3 42.5 47
Equal Percentage 3 1 5/8 0.82 2.9 4.5 6.2 8.8 12.5 17 22 26.3 30.7 34
Equal Percentage 3 3 0.75 9.9 15.6 21.5 30.2 42.9 58.6 75.7 90.4 105.7 117
* For All Non-Venting Back Pressure and Non-Venting Pressure Reducing Regulators, small pressure drops reduce the Cv of the valve:
  • Pressure drops from 10 to 12 psi, multiply valve Cv by 0.9
** with Removable Seat
High Pressure Stem Guided Non-Balanced Control Valve
  Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
High Pressure Control Valve Stem Guided
Equal Percentage 1 1/8 0.73 0.01 0.02 0.03 0.04 0.06 0.09 0.15 0.26 0.32 0.34
Equal Percentage 1 1/4 0.66 0.05 0.10 0.14 0.19 0.29 0.58 0.93 1.27 1.63 1.99
Equal Percentage 1 1/2 0.78 0.16 0.32 0.47 0.60 0.93 1.74 2.99 4.41 5.65 6.49
Linear (Nominal) 1 1/8 0.58 0.1 0.4 0.5 0.7 0.9 1 1 1 1.1 1.1
Linear (Nominal) 1 3/16 0.59 0.2 0.5 0.77 1 1.3 1.4 1.5 1.5 1.5 1.5
Linear (Nominal) 1 1/4 0.78 0.28 0.72 1.11 1.5 1.8 1.95 2.08 2.13 2.15 2.17
Linear (Nominal) 1 3/8 0.91 0.4 1.1 1.6 2.2 2.7 2.9 3.1 3.2 3.2 3.2
Linear (Nominal) 1 1/2 0.94 0.7 1.9 2.9 4 4.8 5.2 5.5 5.6 5.7 5.7
Equal Percentage 2 1/4 0.65 0.1 0.14 0.19 0.23 0.27 0.55 0.82 1.12 1.62 1.72
Equal Percentage 2 7/16 0.60 0.1 0.3 0.5 0.7 1 1.5 2.6 3.8 4.8 5.4
Equal Percentage 2 & 3 * 5/8 0.58 0.3 0.5 0.9 1.1 1.4 2.3 3.9 6.4 8.7 10.8
Equal Percentage 2 & 3 * 7/8 0.66 0.4 0.9 1.57 2.1 3 4.2 6.3 9.6 13 17
Linear (Nominal) 2 & 3 * 1/4 0.55 0.4 1 1.5 2 2.5 2.7 2.8 2.9 2.9 3
Linear (Nominal) 2 & 3 * 3/8 0.77 0.53 1.33 2.06 2.8 3.4 3.6 3.9 4 4 4
Linear (Nominal) 2 & 3 * 1/2 0.78 0.94 2.38 3.67 4.97 5.98 6.48 6.91 7.06 7.13 7.2
Linear (Nominal) 2 & 3 * 3/4 0.80 1.6 4 6.2 8.4 10.1 11 12 12 12 12
Linear (Nominal) 2 & 3 * 1 0.77 2.8 7 11 15 18 19 20 21 21 21
Quick Opening 1 1/8 0.73 0.39 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40
Quick Opening 1 3/16 0.74 0.77 0.90 0.92 0.92 0.92 0.92 0.92 0.92 0.92 0.92
Quick Opening 1 1/4 0.68 0.88 1.51 1.67 1.71 1.73 1.74 1.74 1.74 1.74 1.74
Quick Opening 1 3/8 0.74 1.02 2.40 3.36 3.64 3.73 3.78 3.82 3.83 3.86 3.86
Quick Opening 1 1/2 0.90 1.09 2.46 4.17 5.03 5.27 5.45 5.60 5.72 5.85 5.93
Quick Opening 1 1 0.65 N/A N/A N/A N/A N/A N/A N/A N/A N/A 9.95
Quick Opening 2 1/4 0.65 1.23 1.82 1.87 1.87 1.87 1.87 1.87 1.87 1.87 1.87
Quick Opening 2 3/8 0.76 1.65 3.41 3.77 3.83 3.84 3.84 3.84 3.84 3.84 3.84
Quick Opening 2 1/2 0.80 2.26 4.35 5.87 6.36 6.51 6.58 6.61 6.63 6.63 6.63
Quick Opening 2 3/4 0.78 2.16 4.61 7.23 9.19 10.2 10.6 10.9 10.9 10.9 10.9
Quick Opening 2 1 0.7 2.54 5.58 9.30 12.3 14.2 15.1 15.5 15.6 15.6 15.8
Quick Opening 2 1 1/2 ** 0.75 N/A N/A N/A N/A N/A N/A N/A N/A N/A 29.8
* 2" body with 2" flanges, and 2" body with 3" flanges
** Soft Seat. Maximum pressure drop for this trim is 300 PSI
High Pressure Cage Guided Balanced Control Valve
Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
High Pressure Control Valve Cage Guided
Equal Percentage 2 & 3 * 1 1/2 0.75 0.6 1.3 2.2 3.4 5 8.6 14 21 26 28.6
Equal Percentage 2 & 3 * 2 0.76 2 4 6 8 11 20 33 45 51 57
Equal Percentage 3 2 0.75 2.9 4.9 7.4 9.5 12 17.4 28.9 40.8 48.1 52.6
Equal Percentage 3 3 0.75 4 6 10 13 16 26 54 83 97 107
Equal Percentage 4 3 0.75 4 6 9 12 16 25 52 81 95 115
Equal Percentage 4 4 0.75 9 13 18 26 36 64 104 148 197 222
Equal Percentage 6 4 0.75 9 13 18 26 36 64 104 148 197 222
Equal Percentage 6 6 0.75 7 20 45 78 108 140 222 318 399 431
Equal Percentage 8 6 0.75 47 60 90 106 119 139 173 243 294 453
Equal Percentage 8 8 0.75 51 55 64 134 162 330 452 527 571 630
Modified EP 8 8 0.75 51 53 235 362 485 584 665 699 745 810
Equal Percentage 10 6 0.75 26 37 46 53 56 58 104 146 655 655
Equal Percentage 10 8 0.75 21 22 27 103 209 429 596 663 695 884
Modified EP 10 8 0.75 28 72 420 509 632 678 769 814 832 1091
* 2" body with 2" flanges, and 2" body with 3" flanges
Three Way Control Valve
  Valve Type Trim Type Connection Size (in.) Trim Size (in.) Cf Cv (Thru port) Cv (Lower port)
Three Way Control Valve
High Pressure N/A 1 13/16 0.70 8.3 13.8
High Pressure N/A 2 1 1/2 0.70 27.7 38.1
Splitter Valve N/A 2 1 1/4 0.70 7.5 10.5
Splitter Valve N/A 2 1 1/2 0.70 27.7 38.1
Non-Freeze Dump Valve
  Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Non Freeze Dump Valve
Linear (Nominal) 1 1/4 0.72 0.28 0.72 1.11 1.50 1.80 1.95 2.08 2.13 2.15 2.11
Linear (Nominal) 1 3/8 0.74 0.4 1.1 1.6 2.2 2.7 2.9 3.1 3.2 3.2 3.96
Linear (Nominal) 1 1/2 0.77 0.7 1.9 2.9 4 4.8 5.2 5.5 5.6 5.7 6.34
Quick Opening 1 1/4 0.76 N/A N/A N/A N/A N/A N/A N/A N/A N/A 1.85
Quick Opening 1 3/8 0.71 N/A N/A N/A N/A N/A N/A N/A N/A N/A 4.15
Quick Opening 1 1/2 0.73 N/A N/A N/A N/A N/A N/A N/A N/A N/A 5.11
Metering Valve
  Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Metering Valve
Equal Percentage
1 1/4 0.72 0.28 0.72 1.11 1.50 1.80 1.95 2.08 2.13 2.15 2.11
1 1/2 0.78 0.16 0.32 0.47 0.6 0.93 1.74 2.99 4.41 5.65 6.49
2 1/4 0.65 0.10 0.14 0.19 0.23 0.27 0.55 0.82 1.12 1.62 1.72
2 7/16 0.60 0.1 0.3 0.5 0.7 1 1.5 2.6 3.8 4.8 5.44
2 5/8 0.58 0.3 0.5 0.9 1.1 1.4 2.3 3.9 6.4 8.7 10.76
2 7/8 0.66 0.4 0.9 1.57 2.1 3 4.2 6.3 9.6 13 17.4
2 1 1/2 0.75 0.6 1.3 2.2 3.4 5 8.6 14 21 26 28.60
2 2 0.76 2 4 6 8 11 20 33 45 51 57
3 2 0.75 2.9 4.9 7.4 9.5 12 17.4 28.9 40.8 48.1 52.6
3 3 0.75 4 6 10 13 16 26 54 83 97 107
Low Pressure Control Valve
  Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Low Pressure Control Valve
Equal Percentage 1 1/2 0.86 0.5 0.7 1 1.4 2.1 2.8 3.6 4.3 5.1 5.6
Modified EP 1 1 0.86 1.1 1.8 2.4 3.4 4.8 6.6 8.5 10.2 11.9 13.2
Equal Percentage 2 1 1/4 0.84 1.3 2.4 4 6.7 10.4 14.4 16.9 19.7 22.1 24
Modified EP 2 2 * 0.75 4 6.2 8.6 12.1 17.2 23.5 30.4 36.3 42.5 47
Modified EP 2 2 0.75 4.4 6.9 9.5 13.4 19.1 26 33.6 40.2 47 52
Equal Percentage 3 1 5/8 0.82 2.9 4.5 6.2 8.8 12.5 17 22 26.3 30.7 34
Modified EP 3 3 0.75 9.9 15.6 21.5 30.2 42.9 58.6 75.7 90.4 105.7 117
Equal Percentage 4 2 0.80 4.7 7.3 10.1 14.2 20.2 27.5 35.6 42.5 49.7 55
Modified EP 4 4 0.75 17.8 27.9 38.6 54.2 77 105.2 135.9 162.2 189.8 210
Equal Percentage 6 3 0.80 10.2 16 22 30.9 44 60.1 77.7 92.7 108.4 120
Modified EP 6 6 0.75 40.6 63.8 88.1 123.8 176 240.4 310.6 370.7 433.7 480
Pneumatically Operated Liquid Dump Valves
  Model Type Trim Type Body Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Pneumatically Operated Dump Valve
Low Pressure High Volume (LPHV) Linear (Nominal) Thru 2 1 1/2 .75 5.7 8.4 12 14.9 17.6 19.8 22.3 24.4 26.2 28.9
2 2 .75 8.3 15.3 21.5 27.2 31.6 36 39.3 41.6 44 45.8
3 2 .75 11.6 21.5 30.5 38.6 45.7 51.3 55.6 59.1 61.6 64
3 3 .75 17 32.3 46 58.6 70.4 79.6 87.4 94 98.7 103
4 3 .75 17.8 32.9 48.6 61.2 73.1 84.8 94.5 102 108 114
4 4 .75 22.7 42 61.3 76.2 91.3 106 118 128 135 142
Angled 2 1 1/2 .75 3.7 7.9 12.5 15.7 18.6 21.4 24.1 27.2 30.1 33.3
2 2 .75 9.7 16.1 23.3 29.2 35.1 39.3 43.6 46.5 49.4 51.4
3 2 .75 12.5 22.9 32.2 41.8 49.4 56.2 60.8 65.3 68.4 71.7
3 3 .75 18.8 34.8 49 63.7 75.6 86.7 93.9 101 107 113
4 3 .75 18.4 35.5 52 67.9 84.7 96.4 110 120 130 137
4 4 .75 23.6 44.7 64.2 83.2 103 117 132 142 154 162
Diaphragm Balanced N/A 2 1 1/2 0.79 5 8.5 11.7 14.6 17 19 20.5 21.6 22.6 23.3
3 2 1/4 0.79 6.7 11.1 15.6 20.3 23.8 29.2 33.4 37.2 40.7 43.8
4 3 0.79 12 18.9 25.8 32.8 39.9 46.9 53.7 60 65.7 70.1
6 4 7/8 0.79 14.2 21 31.6 61.2 98.3 139 179.7 217.6 250.2 277
Piston Balanced Throttling 4 4 0.75 11.7 18.1 24.8 36.8 58.3 86.1 114 137 152.8 160
Lever Operated Liquid Dump Valves
Model Type Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Lever Operated Dump Valve
Diaphragm Balanced Linear (Nominal) 2 1 1/2 0.79 5 8.5 11.7 14.6 17 19 20.5 21.6 22.6 23.3
3 2 1/4 0.79 6.7 11.1 15.6 20.3 23.8 29.2 33.4 37.2 40.7 43.8
4 3 0.79 12 18.9 25.8 32.8 39.9 46.9 53.7 60 65.7 70.1
6 4 7/8 0.79 14.2 21 31.6 61.2 98.3 139 179.7 217.6 250.2 277
Piston Balanced 2 1 1/2 0.79 5 8.5 11.7 14.6 17 19 20.5 21.6 22.6 23.3
3 2 1/4 0.79 6.7 11.1 15.6 20.3 24.8 29.2 33.4 37.2 40.7 43.8
4 3 0.79 12 18.9 25.8 32.8 39.9 46.9 53.7 60 65.7 70.1
Piston Balanced Throttling 2 1 1/2 0.75 3.5 5 7.4 9.6 11.8 13.9 16.2 18.4 20.4 22.7
2 2 0.75 6.6 12.3 18.4 24.2 29.5 34.1 38 41.2 44 47
3 3 0.75 12.7 18.7 29 41 52.9 63.4 71.9 78.4 83.7 89
Weight Operated Dump Valves
  Trim Type Connection Size (in.) Trim Size (in.) Cf Cv at Stem Travel (% Open)
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Weight Operated Dump Valve
Linear (Nominal) 2 2 0.75 0.6 0.9 4.2 8.9 13.8 18.4 23.4 28.3 33 36.5
2 w/ Reducer Orifice 0.75 - - - - - - - - - 10.7
3 3 0.75 0.7 11.5 21.1 29.1 37.8 48.1 60 72.6 84.2 93.3
3 w/ Reducer Orifice 0.75 - - - - - - - - - 11.0
4 4 0.75 1.4 18.6 38.4 56.6 76.9 98.8 120.5 142.2 159.9 173.5
6 6 0.75 1.5 32.6 68.1 103.8 146.4 195 247 294 337.2 371.9