DeZURIK
Manual G-Series Actuators on PEC Eccentric Valves
Changing Mounting Positions
8. Make sure the plug is still touching the valve seat, then using the new gear, liberally grease
the teeth and journals then drop the gear in over the plug hex making sure the edge of the
gear is close to or will touch the stop screw.
NOTE: The gear has two different length journals. The longer journal must engage the plug
and the shorter journal must stick up thru the actuator cover.
9. Set a new cover gasket on the housing, then install and fasten the top cover on the housing;
make sure the scribe marks line up.
10. Test actuate the valve by turning the handwheel to open the valve. The valve plug must go
90° from the seat and stop as the gear sector hits the stop lug that is cast in the cover. Now
turn the handwheel to close the valve, the plug should contact the seat before the gear hits
the stop screw. If the valve does not operate as described, remove the cover from the gear
housing and make sure the edge of the gear is touching or very close to the stop screw when
the plug is in the closed position.
11. When you are satisfied that the valve is operating properly, put the valve in the closed
position. With the cover bolted in place, slide the pointer and wrenching nut down the plug
stud so it rests on top of the gear sector; the pointer should point to indicate the correct valve
position.
12. Place the spring washers on the plug stud as shown in Figure 5.
13. Screw the lock nut down the plug stud until it is tight and the spring washers are completely
compressed, then back the nut off one full turn.
14. Adjust the position stops. See "Position Stops" section.
Changing Actuator to 90°/270° Positions on 12"–20" (300–500mm) Valves
with Size 16 Actuator Only
When eccentric valves are mounted in a vertical pipeline, or mounted in a horizontal pipeline with the
plug stem horizontal, gravity can cause the plug to swing to a lower position in the valve body when
the gear sector is removed. To avoid this problem, place the plug in the lowest position before
removing the gear sector.
1.
Discontinue flow and relieve pipeline pressure.
2. Remove the lock nut, spring washers, wrenching nut and pointer from the plug stud.
3. Scribe corresponding lines on the actuator cover and housing, then remove the cover screws
and cover from the top of the actuator.
4. Mark which teeth of the rack and gear are engaged and lift the gear sector out of the actuator.
5.
Remove the screws fastening the adapter to the valve.
6. Take out the screws fastening the actuator housing to the adapter.
7. Rotate the adapter on the valve, and the actuator on the adapter until the holes line up and
the actuator is in the desired position. Replace all of the screws.
8. Find the tooth that was marked on the gear sector and count over clockwise five teeth. This is
the tooth that will engage with the marked tooth on the rack. Install the gear sector using the
new tooth engagement, and be sure the gear sector fits on the plug stem properly.
D10063
(Continued)
Page 14
August 2012
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