Metso VD Series, Installation, Maintenance And Operation Instructions

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4.6 Change of the spring range
4.6.1 Change of the spring range: VDD, Air
to close
See Fig. 5,6 and Exploded view (Fig. 9)
We recommend that all seals be replaced when the actua-
tor has been dismantled for servicing.
The actuator must be depressurized and the supply air
pipes disconnected.

Detach the actuator.

Check that the actuator has been depressurized, and
remove air tubing from the upper case (20).

Loose and remove the short hexagon screws (23, 24,
diaphragm case bolts) and the hexagon nuts (25).

Loose and remove the the long hexagon screws (24,
tension bolts) and the hexagon nuts (25) in cross
steps to release spring tension gradually.

Remove the upper case (20).

Loose the stem nut (33) and remove the lock washer
(33a).

Remove the stem rod plate (16) with inserted o-ring
(17) from top stem (18).

Remove the diaphragm (6) and diaphragm plate (13)
and stopper (15) from the top stem (18).

Remove the spring seats (11) and springs (12).

Replace the springs (12) according to required speci-
fication.

Replace the long hexagon screws (24, tension bolts)
and the hexagon nuts (25).

Reassembling: to follow reverse procedures from the
last step through first step.
4.6.2 Change of the spring range: VDR, Air to
open
See Fig. 5,6 and Exploded view (Fig. 10)
We recommend that all seals be replaced when the actua-
tor has been dismantled for servicing.
The actuator must be depressurized and the supply air
pipes disconnected.

Detach the actuator.

Check that the actuator has been depressurized, and
remove air tubing from the lower case (10).

Loose and remove the short hexagon screws (23, 24,
diaphragm case bolts) and the hexagon nuts (25).

Loose and remove the the long hexagon screws (24,
tension bolts) and the hexagon nuts (25). in cross
steps to release spring tension gradually.

Remove the upper case (20).

Remove the spring seats (11).

Replace the springs (12) according to required speci-
fication.

Replace the long hexagon screws (24, tension bolts)
and the hexagon nuts (25).

Reassembling: follow reversed procedures from the
last step through first step.
4.7 Change of the actuator action
4.7.1 Change of the actuator action: VDD,
Air to close --> VDR, Air to open
See Fig. 5 and Exploded view.
We recommend that all seals be replaced when the actua-
tor has been dismantled for servicing.
The actuator must be depressurized and the supply air
pipes disconnected.

Detach the actuator.

Check that the actuator has been depressurized, and
remove air tubing from the upper case (20).
NOTE:
If actuator is equipped with the handwheel, rotate
handwheel to a 'AUTO' position.
CAUTION:
Diaphragm case is under spring tension and is equip-
ped with the long hexagon screws (24, tension bolts)
which must be removal last.
CAUTION:
Checking whether scratched on the top stem (18) and
dirty particles inside of the stem guide (2) and the dia-
phragm and o-rings before reassembling.
NOTE:
Lubricate seal space and new o-ring with Unisilikon L250L
or equal silicone grease.
NOTE:
Set the springs so that the coil ends are located toward
the actuator stem center, this will be assures best perfor-
mance of the actuator.
CAUTION:
Do not over tighten the hexagon screws as this could
possibly warp the diaphragm and cases, see torque
values on the table 6.
NOTE:
If actuator is equipped with the handwheel, rotate
handwheel to a 'free position`.
CAUTION:
Diaphragm case is under spring tension and is equip-
ped with the long hexagon screws (24, tension bolts)
which must be removal last.
NOTE:
Set the springs so that the coil ends are located toward
the actuator stem center, this will be assures best perfor-
mance of the actuator.
CAUTION:
Do not over tighten the hexagon screws as this could
possibly warp the diaphragm and cases, see torque
values on the table 6.
NOTE:
If actuator is equipped with the handwheel, rotate
handwheel to a 'AUTO' position.