16
EB 8039 EN
Maintenance
Table 4:
Control pressure and max. differential pressure Δp
max
Valve size
DN
15
20
25
32
40
50
65
80
100
NPS
½
¾
1
–
1½
2
2½
3
4
Flow coefficient
K
VS
6.3
10
14
25
31
40
72
90
170
C
V
7.5
12
16
–
36
47
84
105
200
Max. control pressure
1)
6 bar/88 psi
Standard version
Fail-close
Min. control pressure to open the
valve at Δp
max
4 bar/58 psi
Max. perm.
differential
pressure
∆p
max
Vapors, gases A
B
20 bar/290 psi
16 bar/235 psi
10 bar/145 psi
10 bar/
145 psi
Liquids B
A
16 bar/235 psi
10 bar/145 psi
5 bar/73 psi
Fail-open
Min. control pressure to close the
valve at Δp
max
4.5 bar/65 psi
4 bar/
58 psi
Max. perm. differential pressure
Δp
max
for vapors, gases or liquids
20 bar/290 psi
16 bar/235 psi
10 bar/145 psi
Special version for
fail-close version for higher differential pressure Δp
Min. control pressure to open the
valve at Δp
max
5.5 bar/80 psi
–
Max. perm. differential pressure
Δp
max
for vapors, gases or liquids
2)
30 bar/435 psi
20 bar/290 psi
7 bar/102 psi
–
1)
The pressure must not exceed the nominal pressure of the valve body.
2)
For direction of flow B
A
Summary of Contents for 3351
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