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Installation, Operation and Maintenance Manual
MAN616_EAC Rev. 5
July 2020
Section 5: Maintenance
Maintenance
5.2
Extraordinary Maintenance
If there are leaks in the hydraulic cylinder, pneumatic cylinder or a malfunction in the
mechanical components, or in case of scheduled preventive maintenance, the actuator
must be disassembled and seals must be replaced with reference to the follow general
sectional drawing and adopting the following procedures.
!
WARNING
If the actuator can be operated, it is essential to take it to fail safe position, with the spring
totally extended, otherwise the actuator should be disassembled from the valve and follow
these steps described below.
•
Remove the plug (26) from the cover of the adjustment screw (26).
•
Record the length between end flange and stop-setting screw, as in Figure 25 below.
•
Bring the adjustment screw back to the maximum (26) to let the spring loosen.
Stop setting screw cover
Stop setting screw
Figure 25
!
WARNING
Before disassembling the cylinder, make sure the above operation of spring release is done.