Samson 3251-E, Mounting And Operating Instructions

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EB 8052-E EN 9-5
Servicing and conversion
9.2 Preparation for servicing
or conversion work
Risk of personal injury due to incorrect
removal of the anti-rotation fixture under
tension.
Once the actuator has been mounted on the
valve and the assembly is ready for use, the
clamps (301) of the anti-rotation fixture on
the plug stem are under tension.
Î
Follow the instructions in this document
during mounting or removal.
Î
Do not loosen the screws (303) of the
anti- rotation fixture while the force
generated by the supply air and/or the
actuator springs is transmitted to the
actuator stem and the stem (9).
Î
First remove the actuator from the valve
or ensure it cannot transmit any forces to
the actuator stem before removing the
anti-rotation fixture on the plug stem.
Risk of control valve damage due to incor-
rect servicing or conversion.
Î
Do not attempt to perform service or
conversion work yourself on valve
versions with pressure balancing.
Î
Contact our after-sales service for service
or conversion work on valve versions
with pressure balancing.
1. Lay out the necessary material and tools
to have them ready for the intended
work.
2. Put the control valve out of operation (see
the 'Decommissioning' section).
3. Remove the actuator from the valve. See
associated actuator documentation.
To remove an actuator with "stem extends"
fail-safe action and/or with preloaded
springs, a certain signal pressure must be
applied to the actuator (see associated actu-
ator documentation). Afterwards, the signal
pressure must be removed and the air supply
disconnected again and locked.
The valve can remain installed in the pipeline
during service or conversion work, provided
the valve installation conditions permit it. If
this is not the case, we recommend removing
the valve from the pipeline before perform-
ing such work (see the 'Removal' section).
The following service and/or conversion
work can be performed after preparation is
completed:
− Replace the gaskets (see section 9.4.1)
− Replace the packing (see section 9.4.2)
− Replace the trim (see section 9.4.3)
WARNING !
NOTICE
!
Note
Tip