Decommissioning And Disassembly; Decommissioning; Removing The Actuator From The Valve; 120 Cm² Version - Samson 3371 Series Mounting And Operating Instructions

Decommissioning and disassembly

9 Decommissioning and disas-
sembly
DANGER
!
Risk of bursting in the actuator.
Actuators are pressurized. Improper opening
can lead to actuator components bursting.
Before starting any work on the actuator, de-
pressurize all plant sections concerned and
the actuator.
WARNING
!
Risk of personal injury due to preloaded
springs.
Actuators with preloaded springs are under
tension. They can be identified by the long
bolts protruding from the bottom of the actu-
ator. Before starting any work on the actua-
tor, relieve the compression from the pre-
loaded springs (see section 9.3).

9.1 Decommissioning

To decommission the actuator for service and
repair work or disassembly, proceed as fol-
lows:
1. Put the control valve out of operation.
See associated valve documentation.
2. Disconnect the pneumatic air supply to
depressurize the actuator.
46
9.2 Removing the actuator
from the valve
9.2.1 120 cm² version
For mounting using crossbeam (Form B)
1. Put the control valve out of operation.
See associated valve documentation.
2. Remove the clamps of the stem connector
(A30) from the actuator.
3. Removing actuators with "stem ex-
tends" action with/without preloaded
springs: to undo the central nut (98), ap-
ply approx. 50 % signal pressure to open
the valve.
4. Unscrew the central nut (98) from the
plug stem.
5. Disconnect the signal pressure again.
6. In the "actuator stem retracts" version:
detach the external piping.
7. Lift the central nut (98) and actuator off
the valve.
8. Screw tight the central nut (98) on the
valve.
9. Screw tight the stem connector clamps
(A30) onto the actuator. Observe tight-
ening torques.
NOTICE
!
The actuator can be damaged.
Do not loosen the rod nuts (A72) that hold
the crossbeam (A17) on the rods (A11).
EB 8317 EN