Size P900 Actuator - Emerson Fisher 3025 Instruction Manual

3025 Actuator
May 2011
12. Align the diaphragm casings and diaphragm holes. Be sure the vent and air connection on the diaphragm casings
are still diametrically opposed. Install the cap screws and nuts (keys 45 and 46). Tighten the diaphragm cap screws
and nuts in the following manner.
13. The first four bolts tightened should be diametrically opposed and 90 degrees apart. Tighten these four bolts to 8
NSm (6 lbfSft).
14. Tighten the remaining bolts in a clockwise, crisscross pattern to 8 NSm (6 lbfSft).
15. Repeat this procedure by tightening four bolts, diametrically opposed and 90 degrees apart, to a torque of 16
NSm (12 lbfSft).
16. Tighten the remaining bolts in a clockwise, crisscross pattern to 16 NSm (12 lbfSft).
17. After the last bolt is tightened to 16 NSm (12 lbfSft) all of the bolts should be tightened again to 16 NSm (12 lbfSft)
in a circular pattern around the bolt circle.
18. Once completed, no more tightening is recommended.
19. Screw the locknut (key 62) against the nut (key 16).
20. Place the bellows (key 68 and 69).
21. Place the gasket (key 71) and the lifting lug cap (key 40) onto one of the diaphragm casings according to the
actuator action (air-to-close: key 1, air-to-open: key 3). Coat the cap screws (key 44) with lithium grease and
tighten them.
22. If removed, place the travel stop and the locknut (keys 41 and 42) into the lifting lug cap.
23. If the actuator is equipped with a side-mounted handwheel, it is necessary to adjust the actuator travel stop
before mounting the actuator onto the side-mounted handwheel. Perform the Travel Stop Adjustment in
accordance with the procedures in the Installation section. Then refer to the Side-Mounted Handwheel Assembly
procedures in the Side- Mounted Handwheel Maintenance section to complete the actuator assembly (from step
9).
24. Lift the actuator and place it onto the yoke. Insert the cap screws (key 77) and tighten them.
25. If removed, screw the vent (key 49) into the diaphragm casing (key 3).
26. Mount the actuator onto the valve in accordance with the procedures in the Installation section.

Size P900 Actuator

Size P900 Actuator Disassembly
1. Bypass the control valve. Reduce the loading pressure to atmospheric, and remove the tubing or piping from the
diaphragm casings (key 1).
2. If the actuator is equipped with a side-mounted handwheel, refer to the Side-Mounted Handwheel Disassembly
procedures in the Side-Mounted Handwheel Maintenance section to separate the actuator and handwheel (steps 2
to 7). Then continue the Size P900 Actuator Disassembly procedure from the step 8.
3. For an air-to-open actuator only: slightly pressurize the actuator diaphragm until movement of the actuator stem is
detected. The spring force applied to the stem connector is relieved.
WARNING
To avoid personal injury due to sudden uncontrolled movement of parts, do not loosen yoke cap screws and do not remove
the parts of the stem connector when the stem connector has spring force applied to it.
4. Remove the stem connector cap screws (key 87), the anti-rotator (key 85) and the spacer if used (key 86). Loosen
the stem connector halves locknuts (keys 82 and 83). Remove the stem connector halves.
5. For an air-to-open actuator only: slowly exhaust the diaphragm pressure.
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Instruction Manual
D251402X012