July 2020
Installation, Operation and Maintenance Manual
MAN 573 Rev. 8
Replacement of mechanism seals
(see Sectional drawing)
To replace the O-Rings of the shaft (6) proceed as follows:
1.
Remove the retainer ring (21).
2.
Disassemble the shoulder washer (8). Remove the existing O-Ring (23) from its groove.
Clean the groove and the shaft carefully and lubricate it with protective grease film.
3.
Assemble the new O-Ring into its groove and lubricate it with protective grease film.
Assemble the shoulder washer (8). Assemble the retainer ring (21).
If the sealing washer (17) has to be replaced, measure the protrusion of the stop screw (30) with
reference to the housing (1) surface, so as to be able to easily restore the setting of the actuator
mechanical stop, once the maintenance procedures have been completed.
1.
Loosen the lock nut (10) and remove the stop screw (30) together with the nut (10), the
washer (28) and the sealing washer (17). Remove the sealing washer (17) from the stop
screw (30). Carefully clean and lubricate the stop screw thread and the surface on the
housing area, where the sealing washer is.
2.
Screw the new sealing washer onto the stop screw until it is in contact with the nut (10).
Assemble the washer (28) onto the sealing washer (17).
3.
Screw the stop screw into the threaded hole of the housing until it reaches its original
position (the same protrusion with reference to the housing surface). Check that the sealing
washer (17) and the washer (28) are in contact with the housing surface. Tighten the lock
nut (10).
If the sealing washer (18) has to be replaced, measure the protrusion of the thrust bearing screw (15)
with reference to the housing (1) surface, so as to be able to easily restore the setting of the position
of the thrust bearing sliding block with reference to the rack once the maintenance procedures have
been completed.
1.
Loosen the locknut (26) and remove the screw (15) together with the sliding block (19),
the nut (26), the washer (27) and the sealing washer (18). Remove the sealing washer (18)
from the screw (15). Carefully clean and lubricate the screw thread and the surface of the
housing area, where the sealing washer is.
2.
Screw the new sealing washer onto the screw until it is in contact with the nut (26).
3.
Assemble the washer (27) onto the sealing washer (18).
4.
Screw the thrust bearing screw (15), complete with the sliding block (19), into the threaded
hole of the housing until it reaches its original position (the same protrusion with reference
to the housing surface).
5.
Check that the sealing washer (18) and the washer (27) are in contact with the housing
surface. Tighten the lock nut (26).
NOTICE
After maintenance operations, carry out a few actuator operations to check that its movement is
regular and that there is no air leakage through the seals.
Maintenance
24
Section 5: Maintenance
