Mesto Neles XH Series, Installation Maintenance And Operating Instructions

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1 XH 70 en 11
7 TROUBLE SHOOTING TABLE
The following Table 3 lists malfunctions that might occur
after prolonged use.
Table 3. Trouble shooting
8 TOOLS
In addition to standard tools, the following special tools
might facilitate some phases of the work.
‰
For removal of the actuator:
- extractor (ID-code table in actuator's IMO).
This tool can be ordered from the manufacturer. Always give
the valve type designation when ordering.
9 ORDERING SPARE PARTS
When ordering spare parts, always include the following
information:
‰
type code, sales order number, serial number
‰
number of the parts list, part number, name of the
part and quantity required
This information can be found from the identification plate
or documents.
Symptom Possible fault Recommended action
Leakage through a
closed valve Wrong stop screw adjustment of the actuator Adjust the stop screw for closed position
Faulty zero setting of the positioner Adjust the positioner
Damaged seat Replace seat
Damaged closing member Replace the closing member
Closing member in a wrong position relative to the actuator Select the correct keyway in the actuator
Leakage through
body joint Damaged gasket Replace the gasket
Loose body joint Tighten the nuts or screws
Irregular valve
movements Actuator or positioner malfunction Check the operation of the actuator and
positioner
Process medium accumulated on the sealing surface Clean the sealing surfaces
Closing member or seat damaged Replace the closing member or seat
Crystallizing medium has entered the bearing spaces Flush the bearing spaces
Gland packing leaking Gland packing worn or damaged Replace the gland packing
Loose packing Tighten the packing nuts