Samson EB 8111 EN, Монтаж и эксплуатация

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9-4 EB 8111/8112 EN
Servicing
Inspection and testing Action to be taken in the event of a negative result:
Check the valve's seat leakage. Shut off the section of the pipeline and flush the valve to
remove any dirt and/or deposited foreign particles between
the seat and plug.
Check the valve for external damage
(e.g. corrosion).
Remove any damage immediately. If necessary, put the
control valve out of operation (see the 'Decommissioning'
section).
Check the valve accessories to ensure
they are mounted properly.
Tighten the connections of the valve accessories.
Check to ensure that the actuator and
plug stem move smoothly.
Unblock a blocked actuator and plug stem.
WARNING! A blocked actuator or plug stem (e.g. due to
seizing up after remaining in the same position for a long
time) can suddenly start to move uncontrollably. Injury to
hands or fingers is possible if they are inserted into the
actuator or valve.
Before trying to unblock the actuator or plug stem,
disconnect and lock the pneumatic air supply as well as the
control signal. Disconnect the supply voltage. Before
unblocking the actuator and piston stem, release any stored
energy in the actuator (e.g. spring compression). See
associated actuator documentation.
If possible, check the valve's fail-safe
position by briefly interrupting the air
supply.
Put the control valve out of operation (see the
'Decommissioning' section). Identify the cause for the
malfunction and rectify it (see the 'Troubleshooting' section).
9.2 Preparing the valve for
service work
1. Lay out the necessary material and tools
to have them ready for the service work.
2. Put the control valve out of operation (see
the 'Decommissioning' section).
3. Remove the actuator from the valve. See
associated actuator documentation.
How to remove or mount the actuator for
service work depends on the type of attach-
ment (form B or form C, see the 'Mounting
the actuator onto the valve' section).
To remove the actuator (form B) from the
valve, the central nut (98) must be loosened.
Note