Size P460 Actuator - Emerson Fisher 3025 Instruction Manual

Instruction Manual
D251402X012
Key numbers refer to figures 3 through 12 unless otherwise indicated. Figure 3 and 4 show the size P460, figure 5 and
6 the size P462, figure 7 and 8 the size P460-200 and figures 9 through 12 illustrate the size P900.
It may be necessary to apply a temporary loading pressure to the actuator during the disassembly.

Size P460 Actuator

Size P460 Actuator Disassembly
1. Bypass the control valve. Reduce the loading pressure to atmospheric, and remove the tubing or piping from the
diaphragm casing (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 P460 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 and 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 locknut or cap screws and do
not remove 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), the spacer if used (key 86) and the travel
scale indicator (key 84). Loosen the stem connector halves cap screws and nuts (keys 80 and 81). Remove the stem
connector halves.
5. For an air-to-open actuator only: slowly exhaust the diaphragm pressure.
6. To separate the actuator from the valve body, remove the yoke locknut or the bolts and then lift off the actuator.
7. Remove the yoke cap screws (key 77) and then lift the actuator off the yoke.
8. Remove the lifting lug cap screws (key 44), the lifting lug (key 40) and the gasket (key 71). If required remove the
cap (key 43) and the travel stop (key 41).
WARNING
To avoid personal injury from the precompressed spring force thrusting the diaphragm casing away from the actuator,
carefully remove casing cap screws and nuts (keys 45 and 46) (step 9 below) and then relieve the spring compression by
unscrewing the nut (key 16) (step 11 below).
9. Remove all the diaphragm casing cap screws and nuts (keys 45 and 46). If required remove the vent (key 49).
10. Remove the set screws (key 57) and if used the travel stop and locknut (keys 65 and 66).
11. Relieve the spring compression by unscrewing slowly the nut (key 16).
12. Remove the washer (key 53), then lift off the diaphragm casing (key 3).
13. Remove the actuator springs (keys 30 and 31).
14. Lift off the stem and diaphragm plate assembly.
15. Unscrew the travel stop (key 54), remove ring (key 17), the wave washers (key 12), the tube (key 51), the
diaphragm plate (key 26), the diaphragm (key 47), the O-ring (key 6), the washers if used (key 64) and the travel
stop (key 14). Unbend the tab washer (key 13), remove the retaining ring (key 11) and the two nut halves (key 10).
3025 Actuator
May 2011
7