EB 8048 EN
17
Design and principle of operation
3.3 Additional fittings
Safety guard
For operating conditions that require in-
creased safety (e.g. in cases where the valve
is freely accessible to untrained staff), a safe-
ty guard must be installed to rule out a crush
hazard arising from moving parts (actuator
and plug stem). Plant operators are responsi
-
ble for deciding whether a guard is to be
used. The decision is based on the risk posed
by the plant and its operating conditions.
Test connection
A pressure sensor can be connected at the
test connection (4.4) in the valve bonnet of
the special valve version with packing to
monitor the diaphragm for leakage.
1
Valve body
3
Plug
4.1
Spring
4.2
Packing
4.3
Washer
4.4
Test connection
5
Valve bonnet
5.1
Guide bushing
5.2
Threaded bushing
5.3
Yoke
5.4
Screws
5.5
Travel indicator scale
5.6
Clamp
6
Plug stem
6.1
Stem connector nut
6.2
Lock nut
6.3
Diaphragm
6.4
Grub screw
7
Stem connector
8
Actuator
8.1
Actuator stem
8.2
Ring nut
8.3
Compression spring
8.4
Rolling diaphragm
9
Signal pressure connection
10
Vent screw