Engineering Data 
CPV has conducted extensive flow tests and has established flow constants as Cv factors for each size valve.  The Cv is defined as the gallons of water in a one minute period that will flow thru a valve in the full open position creating a pressure drop of 1 psi. 
  The pressure drop orfor liquids can be calculated using formula #1 and inserting the proper specific gravity. 
  The pressure drop for gases can be calculated by using formula #2 and inserting the proper specific gravity of the gas. 
Cv Factors
ORIFICE 
SIZE  INCH  MM
GLOBE 
Cv
ANGLE 
Cv
0
.218
5.5
1
.313
8.0
2
.438
11.1
3
.500
12.7
4
.625
15.9
5
.813
20.7
 
.9
2.0
4.3
6.1
9.2
16.2
 
1.3
2.8
6.0
8.5
12.9
22.7
 
 
Specific Gravity
GAS S.G.
 
LIQUID S.G.
 
AIR*  1.0
ARGON  1.377
CO2  1.516
HELIUM  0.138
HYDROGEN  0.069
NITROGEN  0.966
OXYGEN  1.103
 
WATER*  1.0
ACETONE  0.79
ALCHOHOL  0.79
BENZENE  0.902
KEROSENE  0.815
 
*@68°F/20°C		 Panel Mount Information 
ORIFICE 
SIZE INCH MM
G OPEN 
INCH MM
H 
INCH MM
J MAX. 
INCH MM
K 
INCH MM
0
.218
5.5
1
.313
8.0
2
.438
11.1
3
.500
12.7
4
.625
15.9
5
.813
20.7
 
4.53
115.1
4.80
122.0
5.41
137.4
6.50
165.1
6.38
162.1
7.72
196.1
 
3.50
88.9
3.50
88.9
3.50
88.9
4.50
114.3
5.25
133.4
7.25
184.2
 
.25
6.4
.44
11.2
.44
11.2
.69
12.1
.56
14.2
.88
22.4
 
1.20
30.5
1.20
30.5
1.53
38.9
1.78
45.2
1.78
45.2
2.16
54.9
 
  
 
Standard and custom fittings
 
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CPV Manufacturing, Inc.  Phone: (215) 386-6508  Fax: (888) 387-9043