Decommissioning - Samson 3371 Mounting And Operating Instructions

10 Decommissioning

The work described in this section is only to
be performed by personnel appropriately
qualified to carry out such tasks.
DANGER
!
Risk of bursting due to incorrect opening of
pressurized equipment or components.
Pneumatic actuators are pressure equipment
that may burst when handled incorrectly.
Flying projectile fragments or components
can cause serious injury or even death.
Before working on the actuator:
Î Depressurize all plant sections concerned
and the actuator. Release any stored en-
ergy.
WARNING
!
Risk of personal injury due to preloaded
springs.
Actuators with preloaded springs are under
tension. These actuators can be identified by
several longer bolts with nuts protruding
from the bottom diaphragm case. Actuators
with considerably preloaded springs are also
labeled correspondingly (see 'Warnings on
the device' in the 'Safety instructions and
measures' section).
Î Only open the actuator following the in-
structions in this document. See 'Reliev-
ing the spring compression in the actua-
tor' in the 'Removal' section.
EB 8317 EN
WARNING WARNING
! !
Risk of personal injury due to exhaust air
being vented.
The actuator is operated with air. As a result,
air is vented during operation.
Î Wear eye and hearing protection when
working near the actuator.
WARNING WARNING
! !
Crush hazard arising from the moving
actuator stem.
Î Do not insert hands or finger into the
yoke while the air supply is connected to
the actuator.
Î Before working on the actuator, discon-
nect and lock the pneumatic air supply
as well as the control signal.
Î Do not impede the movement of the actu-
ator stem by inserting objects into the
yoke.
Î Before unblocking the actuator stem after
it has become blocked (e.g. due to
seizing up after remaining in the same
position for a long time), release any
stored energy in the actuator (e.g. spring
compression). See 'Relieving the spring
compression in the actuator' in the
'Removal' section.
To decommission the actuator for service
work or before removing it from the valve,
proceed as follows:
1. Put the control valve out of operation.
See associated valve documentation.
2. Disconnect the pneumatic air supply to
depressurize the actuator.
Decommissioning
10-1