14
EB 8139 EN
Design and principle of operation
3.4 Permissible differential pressures
The specifications for the standard version have a dark gray background.
3.4.1
Version FA/NC with fail-safe position: fail-close
Pressure rating
DN
15 · 20
25 · 32
40 · 50
NPS
½ · ¾
1 · 1¼
1½ · 2
Actuator
Signal
pressure
∆p
Actuator area
Thrust
30 cm²
720 N
4.0 bar
17
6
2
60 cm²
1440 N (one spring)
3.8 bar
40
16
6
2160 N (two springs)
5.4 bar
–
25
10
3.4.2
Version FE/NO with fail-safe position: fail-open
Required actuators and signal pressures to close the valve at the specified differential pres
-
sure. Assigned according to valve size and actuator area.
Control valve DN 15 · DN 20
Pressure
rating
DN
15 · 20
Control valve DN 15 (NPS ½) · DN 20 (NPS ¾)
NPS
½ · ¾
∆
60 cm²/Ø90
30 cm²/Ø63
0
3
4
5
6
7
8
5
10
15
20
25
30
35
40
p
[bar]
[bar]
pzul
Actuator
Signal
pressure
∆p
30 cm²
Ø = 63 mm
4 bar
6
5 bar
16
6 bar
26
7 bar
36
8 bar
40
60 cm²
Ø = 90 mm
3 bar
27
4 bar
40
