Emerson Fisher 3025 Instruction Manual page 17

Instruction Manual
D251402X012
13. 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.
14. The first four bolts tightened should be diametrically opposed and 90 degrees apart. Tighten these four bolts to 8
NSm (6 lbfSft).
15. Tighten the remaining bolts in a clockwise, crisscross pattern to 8 NSm (6 lbfSft).
16. Repeat this procedure by tightening four bolts, diametrically opposed and 90 degrees apart, to a torque of 16
NSm (12 lbfSft).
17. Tighten the remaining bolts in a clockwise, crisscross pattern to 16 NSm (12 lbfSft).
18. 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.
19. Once completed, no more tightening is recommended.
20. Coat the thread of three cap screws (key 32) and the internal threads of the diaphragm casing (key 3) with
anti-seize lubricant (key 202). Be sure that the cap crew beds into the spring seat are still aligned with the internal
threads of the diaphragm casing. Then install and screw alternately and slowly the three cap screws to compress
the springs.
21. Place the retaining ring (key 59) onto the stem. Install the ring (key 61) and slide the retaining ring and bend it on
the ring.
22. Place the gasket (key 72) and the flange (key 34). Insert the cap screws (key 34) and tighten them.
23. Place the diaphragm casing (key 2) so that the vent connection is diametrically opposed to the air connection of
the diaphragm casing (key 1) next to. Install the lock washers (key 23) and the cap screws (key 22) and tighten
them.
24. Apply anti-seize lubricant (key 202) to the internal thread of the two nut halves (key 10). Install the nut halves and
the retaining ring (key 11). Slide the lock washer (key 50), the diaphragm plate (key 27), the diaphragm (key 48),
the O-ring (key 20), the washer (key 55), the retaining ring (key 11).
25. Coat the internal thread of the two nut halves (key 10) with anti-seize lubricant (key 202) and tighten them until
the lock washer is completely compressed.
26. Place the diaphragm casing (key 1) so that the vent and air connection are diametrically opposed. Take care when
sliding the diaphragm casing around the stem so that the threads do not damage the bushing, O-ring or wiper ring.
Note
When you replace actuator diaphragms in the field, take care to ensure the diaphragm casing bolts are tightened to the proper
load to prevent leakage, but not crush the material. Perform the following sequence with a manual torque wrench.
CAUTION
Over-tightening the diaphragm cap screws and nuts (keys 45 and 46) can damage the diaphragm. Do not exceed 16 NSm
(12 lbfSft) torque.
Note
Do not use lubricant on these bolts and nuts. Fasteners must be clean and dry.
3025 Actuator
May 2011
17