Metso VD Series, Installation, Maintenance And Operation Instructions

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6 DA 70 en 15
4.8 Adjustment for valve stem
4.8.1 Model VDD, Air to close
See Fig. 5, 6, 7, 8 and 9.

With the handwheel or pneumatically, stroke the
actuator to the rated range or stroke.

Unscrew the socket head screws (27) and hexagon
nut (28) by one turn.

Using the stem lock nut, unscrew the stem until the
plug touches the seat.

Release the pressure in the actuator or returned the
handwheel to raise the stem.

Line up the stroke indicator (32) with the clamp
arrow (26) and check actuator for operation.

To adjust with rotating valve stem if the stroke is
inconsistent with the rated stroke.

Tighten the socket head screws (27) and hexagon
nut (28) after adjusted the rated stroke.
4.8.2 Model VDR, Air to open
See Fig. 5, 6, 7,8 and 9.

Keep the actuator stem is fully extended.

Unscrew the socket head screws (27) and hexagon
nut (28) by one turn.

Using the stem lock nut, unscrew the stem until the
plug touches the seat.

With the handwheel or pneumatically, stroke the
actuator to raised the plug off the seat.

Line up the stroke indicator (32) with the clamp
arrow (26) and check actuator for operation.

To adjust with rotating valve stem if the stroke is
inconsistent with the rated stroke.

Tighten the socket head screws (27) and hexagon
nut (28) after adjusted the rated stroke.
4.9 Maximum & minimum stopper
See Fig. 8
5 MALFUNCTIONS
6 TOOLS
Removal of the actuator

wrench set (mm)

hex socket wrench set

chisel and hammer (10 pound)

drivers
7 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.
CAUTION:
Avoid to turn the valve plug and stem when plug is on
seat ring to prevent the seating line from being dama-
ged.
CAUTION:
Avoid to turn the valve plug and stem when plug is on
seat ring to prevent the seating line from being dama-
ged.
Fig. 8 Max./Min. stopper
Model VDD
Maximum stop
Optional Adjustable Limit stop
Model VDR
Minimum stop
Optional Adjustable Limit stop
Table 7. Possible malfunctions
Symptom Possible cause Action
Irregular or slow operation Low supply pressure Make sure that supply pressure complies with minimum
force required by valve.
Check that supply air pipes are large enough.
Positioner fault Check positioner operation.
Valve fault Check that valve functions properly without actuator.
Incorrect actuator rating Contact manufacturer to check rating.
Leak in diaphragm case or O-rings Replace O-rings. See sect. 4.2 or 4.3, depending on
actuator type.
NOTE:
Always use original spare parts to make sure that the valve
functions as intended.