Emerson Process Management FISHER 657 - Manual (Page 13)

Instruction Manual
D100306X012
657 Actuator (30-70 and 87)
December 2010
13
WARNING
To avoid personal injury from the precompressed spring force thrusting the upper diaphragm casing (key 1) away from the
actuator, thread the spring adjuster (key 12) out of the yoke until all spring compression is relieved, then carefully remove
casing cap screws (key 22).
3. Remove the diaphragm casing cap screws and nuts (keys 22 and 23, figures 6, 7, or 8), and lift off the upper
diaphragm casing and handwheel assembly.
4. If necessary, the handwheel assembly can be separated from the diaphragm casing by removing the cap screws
(key 141). This may be necessary to replace the O‐ring (key 139), or for ease of handling.
5. Loosen the travel stop locknut (key 137), and turn the handwheel (key 51) counter‐clockwise. Remove the cotter
pin and stop nut (keys 247 and 54), then lift off the handwheel.
6. Unscrew the travel stop locknut (key 137) from the handwheel stem (key 133), and turn the stem out of the
bottom of the body (key 142). A screwdriver slot is provided on the top of the stem for this purpose.
7. Replace the O‐ring (key 138) in the body (key 142).
8. For a handwheel assembly used on sizes 30 through 60 actuators, complete the disassembly by driving out the
groove pin (key 140, figure 9) and sliding the pusher plate (key 135, figure 9) off the stem.
For a handwheel assembly used on a sizes 70 or 87 actuator, complete the disassembly by unscrewing the retaining
screw (key 174, figure 10) and removing the thrust bearing and pusher plate (keys 175 and 135, figure 10). Because
the retaining screw (key 174) has left‐hand threads, turn clockwise to loosen.
Assembly for Top‐Mounted Handwheel
1. For a handwheel assembly used on sizes 30 through 60 actuators, coat the end of the handwheel stem (key 133,
figure 9) with anti‐seize lubricant (key 244). Slide the pusher plate (key 135, figure 9), onto the stem, and drive in
the groove pin (key 140, figure 9) to lock the pieces together.
For a handwheel assembly used on a sizes 70 or 87 actuator, pack the thrust bearing (key 175, figure 10) with
anti‐seize lubricant (key 244). Place the thrust bearing in the pusher plate (key 135, figure 10), slide the two parts onto
the handwheel stem (key 133). Coat the retaining screw threads with thread locking sealant (key 242). Insert and
tighten the retaining screw (key 174, figure 10).
2. Coat the O‐ring (key 138) with lithium grease (key 241), and insert the O‐ring in the body (key 142).
3. Coat the threads of the handwheel stem (key 133) with anti‐seize lubricant (key 244). Screw the stem into the body
(key 142).
4. Thread the travel stop locknut (key 137) onto the handwheel stem (key 133).
5. Place the handwheel (key 51), and the stop nut (key 54) on the handwheel stem (key 133). Tighten the hex nut to
fasten the parts together. Secure the nut with the cotter pin (key 247).
6. If the body (key 142) was separated from the upper diaphragm casing (key 1, figures 6, 7, or 8), lubricate the O‐ring
(key 139) with lithium grease (key 241), and place the O‐ring in the body. Align the holes in the diaphragm casing
and the body, insert the cap screws (key 141), and tighten them evenly following a crisscross pattern to ensure a
proper seal.
7. Position the upper diaphragm casing (key 1) on the diaphragm (key 2) and align the holes.
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 tightening sequence with a manual torque wrench for
size 30‐70 and 87 actuators.