9-4 EB 8052-E EN
Servicing and conversion
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 ush the valve to re-
move any dirt and/or deposited foreign particles between
the seat and plug.
Replace the trim (see section9.4.3).
Check the valve for external damage
(e.g. corrosion).
Repair any damage immediately. If necessary, put the con-
trol valve out of operation (see the 'Decommissioning' sec-
tion).
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 or piston stem move smoothly.
Version with adjustable packing
1)
: tighten the packing cor-
rectly (see information under 'Adjusting the packing' in the
'Installation' section > 'Testing the installed valve').
Unblock a blocked actuator and plug or piston stem.
WARNING! A blocked actuator or plug or piston 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 ngers is possible if they are inserted into the
actuator or valve.
Before trying to unblock the actuator or plug or piston stem,
disconnect and lock the air supply as well as the control sig-
nal. Before unblocking the actuator, release any stored en-
ergy in the actuator (e.g. spring compression). See associat-
ed actuator documentation.
If possible, check the valve's fail-safe
position by briey interrupting the air
supply.
Put the control valve out of operation (see the 'Decommis-
sioning' section). Identify the cause for the malfunction and
rectify it (see the 'Troubleshooting' section).
1)
See the 'Markings on the device' section
To Next Page
Loading...
