Fisher GX 3-Way, Инструкция по эксплуатации, Страница: 10 / 28

Instruction Manual
D103312X012
GX 3-Way Valve and Actuator
July 2017
10
b. Remove the stem connector nut half (key 23), stem connector bolt half (key 24), and travel indicator (key 26).
c. Push the valve plug stem (key 3) down until it contacts the lower seat.
d. Loosen the locknut (key 28) and thread the lower stem connector (key 27) down until it clears the top of the
valve plug stem (key 3).
D
For HT construction, loosen locknut (key 108) and thread the stem extension (key 106) down as far as possible
(see figure 12).
e. Shut off the air pressure and disconnect the separate air supply to the lower diaphragm casing (as shown in figure
11).
WARNING
To avoid personal injury or property damage by uncontrolled movement of the actuator yoke (key 8), loosen the body/yoke
nuts (figure 11, key 7) by following the instructions in the next step. Do not remove a stuck actuator yoke by pulling on it
with equipment that can stretch or store energy in any other manner. The sudden release of stored energy can cause
uncontrolled movement of the actuator yoke.
Note
The following step also provides additional assurance that the valve body fluid pressure has been relieved.
2. For fail‐up constructions, as shown in figure 8:
a. Connect a separate air supply to the air supply connection on the upper casing (shown in figure 8) and apply
sufficient air pressure to move the plug/stem to mid‐travel.
b. Remove the stem connector nut half (key 23), stem connector bolt half (key 24), and travel indicator (key 26).
c. Shut off the air pressure and disconnect the air supply to the upper casing.
3. Valve body nuts (key 7) attach the actuator yoke (key 8) to the valve body (key 1). Loosen these nuts approximately
3mm (1/8 inch).
D
For HT constructions,
see figure 12. Nuts (key 7) attach the yoke extension (key 105) to the valve body (key 1).
Loosen these nuts approximately 3mm (1/8 inch). It is not necessary to loosen the nuts which attach the
actuator yoke (key 8) to the yoke extension.
4. Then loosen the valve‐to‐yoke gasketed joint by either rocking the actuator yoke or prying between the valve and
yoke. Work the prying tool around the yoke until it loosens.
WARNING
If there is evidence of process fluid under pressure leaking from the joint, retighten the valve body/joint nuts and return to
the Warning at the beginning of the Maintenance section to ensure proper steps have been taken to isolate the valve and
relieve process pressure.
5. If no fluid leaks from the joint, loosen the packing follower (key 29) two turns to relieve the packing compression
load.
6. Remove the body nuts (key 7) completely.