45
Installation, Operation and Maintenance Manual
MAN 564 Rev. 6
June 2020
Maintenance
Section 5: Maintenance
Replacement of hydraulic cylinder seals (see Figure 41) only for ALGA-MHP hydraulic
handpump manual override
If there are leaks in the hydraulic cylinder or a malfunction in the mechanical components,
or in case of scheduled preventive maintenance, the actuator must be dis-assembled
and seals must be replaced with reference to the sectional drawing and adopting the
following procedures:
1.
Remove the nuts (item 16) and the washers (item 15) from the tie rods (item 10)
at the end flange (item 13) side.
2.
Slide off the end flange and the tube (item 12).
3.
Remove the screws (item 2-Figure 41) and the cover (item 1-Figure 41).
4.
Unscrew the piston rod (item 6) threaded end from the adaptor bush
(item 30-Figure 41) of guide block (item 14-Figure 41).
5.
Slide off the piston rod from the head flange (item 2).
6.
Disassemble the head flange from the mechanism housing (item 8-Figure 41) by
removing the screws (item 7-Figure 41) only if the gasket (item 36-Figure 41) has
to be replaced because damaged.
Seals replacement
Prior to reassemble check that the actuator components are in good conditions and clean.
Lubricate all the surfaces of the parts, which move in contact with other components, by
recommended oil (SHELL OMALA S4 WE or equivalent). If the O-ring must be replaced,
remove the existing one from its groove, clean the groove carefully and lubricate it
with protective oil film. Assemble the new O-ring into its groove and lubricate it with a
protective oil film.
1.
Replace the O-rings (3) of the head flange (2).
2.
Replace the O-ring (3) of the end flange (13).
For replacement of piston rod seal ring (4) and of the O-ring (5) proceed as follows:
1.
Remove the existing Teflon seal ring (4) and the O-ring (5) from their groove.
2.
Clean the groove carefully and lubricate it with a protective oil film.
3.
Assemble the new O-ring into its groove and lubricate it with a protective oil film.
4.
Assemble the new Teflon seal ring (4) into the flange groove, on the rubber
O-ring (5), by bending it: take care that the bending radius is as large as possible
to avoid damaged the seal. Then enlarge the seal ring with your fingers so as to
restore its round shape: pay attention not to utilize any tools, which can damage
the seal ring.
