Emerson Fisher 657 Instruction Manual page 20

657 Actuator (30/30i-70/70i and 87)
June 2018
The adjustable down travel stop (figure 20) 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 18, 19, and 20.
Disassembly for Casing‐Mounted Travel Stop
Bypass the control valve. Reduce the loading pressure to atmospheric, and remove the tubing or piping from the
connection in the body (key 142).
Casing‐Mounted Adjustable Up Travel Stops
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 1 and 2, below), and carefully remove casing cap screws (key 22)
(step 3, below).
1. Thread the spring adjuster (key 12) out of the yoke (key 9) until all spring compression is relieved.
2. 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.
3. Remove the upper diaphragm casing (key 1, figures 6, 7, 8, 9, or 10) as outlined in the Maintenance section.
4. Remove the cap screws (keys 141) and separate the travel stop assembly from the upper casing.
5. Remove and inspect the O‐rings (keys 138 and 139); replace if necessary.
6. Proceed with the following procedure, based on actuator size:
D For sizes 30/30i through 60/60i, drive out the groove pin (key 140), and slide the pusher plate (key 135) off the
travel stop stem (key 133).
D For sizes 70/70i and 87, remove the retaining screw (key 174) to inspect the thrust bearing (key 175).
Casing‐Mounted Adjustable Down Travel Stops
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 1 and 2, below), and carefully remove casing cap screws (key 22)
(step 3, below).
1. Thread the spring adjuster (key 12) out of the yoke (key 9) until all spring compression is relieved.
2. 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.
3. Remove the upper diaphragm casing (key 1, figures 6, 7, 8, 9, or 10) as outlined in the Maintenance section.
4. Remove the cap screws (keys 141) and separate the travel stop assembly from the upper casing.
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Instruction Manual
D100306X012