Installing Cylinder
4. Screw one nut onto the rack rod. Screw the nut down until the spring washers are completely
compressed, then back the nut off until the washers return to their normal shape.
5. Screw the other nut onto the rack rod and tighten the two nuts against each other.
6. Replace the extension cap onto the actuator housing.
7. Reconnect power to the actuator.
8. Adjust the position stops as described in the "Position Stop" section.
9. Pipeline flow may now be restored.
Disassembling Actuator
When tapered plug 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 actuator is removed. To avoid this problem, place the plug in the lowest position before removing
the actuator.
1. Discontinue flow and relieve pipeline pressure.
Accidental operation of power actuator can cause personal injury or equipment damage.
Disconnect and lock out power to actuator before servicing.
2. Apply air pressure to the port in the cylinder cap (the end farthest from the actuator housing)
until the valve has moved to the end of its stroke.
3. Turn off the supply pressure to the cylinder, then disconnect the tubing from both cylinder ports
4. Disconnect and lock out the pneumatic, hydraulic, or electrical power to prevent accidental
operation of the actuator.
5. Scribe corresponding lines on the valve and actuator to help align them during installation.
6. Remove the lock nut from the top of the wrenching square.
7. Remove the four socket head screws and wrenching square.
8. Note the position of the pointer, then remove the two socket head screws and slide the pointer
off the actuator.
9. Remove the plug adjusting nut from the stud and slide the bearing washer off the stud.
10. Scribe corresponding lines on the actuator cover
and housing, then remove the cover screws and
cover from the top of the actuator.
11. Mark the teeth of the rack and gear as shown in
Figure 5 and lift the gear sector out of the actuator.
12. Remove the rack from the housing.
July 2016
Cylinder Operated G-Series Actuator
(Continued)
Page 9
DeZURIK
Figure 5 – Scribe Marks
D10191