Flowserve L120 Series Limitorque Actuation Systems - Manual (Page 28)

Limitorque Actuation Systems L120 Series FCD LMENIM1201-04-AQ – 05/15
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6.3 Disassembly and Reassembly
a CAUTION: Turn off all power services before attempting to perform service on the actuator.
• Remove the actuator from the valve for complex work. Minor work, such as replacing geared limit
switch, torque switch, or motor, may be readily performed while the actuator is still on the valve.
• Potential High-Pressure Vessel. Before removing or disassembling your actuator, ensure that the
valve or other actuated device is isolated and is not under pressure.
NOTE: If the actuator is fitted with a Thrust Base (piece 100 of Figure 6.2), it is possible to remove the
actuator housing while leaving the base on the valve to accept valve thrust. However, it is preferred that
the valve be isolated from service and, if it is a rising stem, that the valve be fully open.
6.4 Disassembly of the L120-10, 20, and 40
Unless otherwise noted, piece numbers refer to the Illustrated Parts Breakdown of Figure 5.2.
1. Turn off power to the actuator.
2. Remove electrical Compartment Cover (piece 200).
3. Disconnect all electrical leads from the Torque Switch (piece 300) and Geared Limit Switch
(piece 305). Ensure that all leads and terminals are clearly marked to facilitate reassembly.
4. Remove two screws holding limit switch and one holding torque switch. Remove both items.
5. Remove four bolts holding Motor (piece 31) and three bolts holding conduit Nipple Flange
(piece 30). Remove motor, drawing motor leads through switch compartment.
6. Remove Motor Pinion (piece 38) by removing Stop Nut (piece 40).
7. Remove Worm Shaft Gear (piece 35), Flexloc Nut (piece 37), and Worm Shaft End Cap (piece 5)
and draw complete wormshaft assembly from housing.
NOTE: The wormshaft has been assembled at the factory to obtain the correct preload on the spring
packs. Do not attempt to disassemble further. If the worm shaft is worn or damaged, it is suggested
that the complete wormshaft subassembly be replaced. The actuator must be in motor operation to
remove the wormshaft assembly. When the wormshaft is partially out, the disc springs will hit the
worm gear. Pull the declutch lever forward slightly without fully engaging the declutch mechanism
and the wormshaft will come out.
8. Remove Declutch Cap (piece 11).
9. For unit size L120-10, completely withdraw the Declutch Assembly (piece 7 of Figure 6.3) from
the housing. For unit sizes L120-20 and 40, remove Declutch Input Pinion (piece 12 of Figure 6.3)
followed by the Declutch Assembly (piece 7 of Figure 6.3).
10. Remove Handwheel (piece 29) and Housing Cover (piece 27) and lift complete drive sleeve subas-
sembly from housing.