Casing‐Mounted Adjustable Up Travel Stops - Emerson FISHER 657 Instruction Manual

657 Actuator (30-70 and 87)
December 2010
The casing‐mounted adjustable up travel stop (figures 14 or 15) limits the actuator stroke in the upward direction. To
adjust, first relieve actuator loading pressure before removing the travel stop cap (key 187, figure 14 or 15). Loosen
the travel stop nut (key 137). Then turn the travel stop stem (key 133) clockwise into the diaphragm case to move the
actuator stem downward (or counter‐clockwise to move the stem upward). Finally, tighten the travel stop nut and
replace the travel stop cap.
The adjustable down travel stop (figure 16) limits the actuator stroke in the downward direction. To adjust, first relieve
actuator loading pressure before removing the travel stop cap (key 187). Then loosen the jam nut and adjust the stop
nut (keys 189 and 54) either down on the stem to limit travel, or up on the stem to allow more travel. Lock the jam nut
against the stop nut, then replace the closing cap.
Instructions are given below for disassembly and assembly. Perform the disassembly only as far as necessary to
accomplish the required maintenance; then, begin the assembly at the appropriate step.
Key numbers are shown in figures 14, 15, and 16.
Disassembly for Casing‐Mounted Travel Stop
1. Bypass the control valve. Reduce the loading pressure to atmospheric, and remove the tubing or piping from the
connection in the body (key 142).
WARNING
To avoid personal injury from the precompressed spring force thrusting the upper diaphragm casing (key 1) away from the
actuator, relieve spring compression (steps 2 and 3, below), and carefully remove casing cap screws (key 22) (step 4,
below).
2. Thread the spring adjuster (key 12) out of the yoke (key 9) until all spring compression is relieved.
Casing‐Mounted Adjustable Up Travel Stops
1. Remove the travel stop cap (key 187) and loosen the travel stop nut (key 137). Rotate the travel stop stem (key
133) counter‐clockwise until the travel stop assembly is no longer compressing the spring.
2. Remove the upper diaphragm casing (key 1, figures 6, 7, or 8) as outlined in the Maintenance section.
3. Remove the cap screws (keys 141) and separate the travel stop assembly from the upper casing.
4. Remove and inspect the O‐rings (keys 138 and 139); replace if necessary.
5. For sizes 30 through 60, drive out the groove pin (key 140), and slide the pusher plate (key 135) off the travel stop
stem (key 133).
For sizes 70 and 87, remove the retaining screw (key 174) to inspect the thrust bearing (key 175).
Casing‐Mounted Adjustable Down Travel Stops
1. Remove the travel stop cap (key 187). Unscrew the jam nut and stop nut (keys 189 and 54) until the travel stop
assembly is no longer compressing the spring. Remove the jam nut and stop nut.
2. Remove the upper diaphragm casing (key 1, figures 6, 7, or 8) as outlined in the Maintenance section.
3. Remove the cap screws (keys 141) and separate the travel stop assembly from the upper casing.
4. Remove and inspect the O‐ring (keys 139); replace if necessary.
5. Loosen the stop nut (key 54), then unscrew the travel stop stem (key 133) out of the actuator stem. The lower
diaphragm plate can now be removed.
Assembly for Casing‐Mounted Travel Stop
1. Reassemble the up or down travel stop in the reverse order of the disassembly steps, being sure to apply lubricant
as shown by the lubrication boxes (key 241) in figures 6, 7, 8, 14, 15, or 16, as appropriate.
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Instruction Manual
D100306X012