EP Equipment CQD16, Service Manual

Page: 100 / 251

86
REV. 07/2016
HYDRAULIC SYSTEM
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7.8 Reach Cylinder
7.8.1 Cylinder Removal Precautions
Before removing the cylinder, be sure to reli-
eve the hydraulic circuit
fi rst, which is to lower
the lifting mast to the bottom. Otherwise,
when removing the tubing connected with the
cylinder, the pressured hydraulic oil within
the circuit may be sprayed out at high speed
along with the tubing, and there is risk of
causing personal injury.
Turn off the power source, so that the entire
hydraulic system will stop functioning, then
the connecting tubing can be loosened; in
order to avoid the residual pressure within the
circuit, the tubing joint should be loosened
slowly, loosen the joint by half and shake the
tubing to see if there is over
fl ow of pressured
oil, and then go on with the removal;
Cylinder is the powered actuator in hydraulic
system. Therefore, before removing the
cylinder from the equipment, the connection
part must be supported with appropriate
supporting to avoid personal injury or damage
to the equipment;
Cylinder is the powered actuator in hydraulic
system. Therefore, before removing the
cylinder from the equipment, the connection
part must be supported with appropriate
supporting to avoid personal injury or damage
to the equipment;
Upon disassembly of the cylinder, you should
know the main structure of the cylinder to
avoid sightless removal. Due to the different
size, structure, purpose of use of the
cylinders, the sequences and methods used
for removal are also different;
When removing each part, do not hammer
forcefully, it such case cannot be avoided,
please lay a copper rod to avoid damage
to the parts; special tools must be used for
the parts having such requirements, do not
hammer forcefully or pry. Fine pitch threaded
cylinder cap, after being shaken loose,
loosen it with cylinder wrench with even force,
copper rod can be used to hammer the part
that cannot easily deform, do avoid violent
shocks.
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Upon removal, the damage to cylinder
threads, oil port threads, cylinder cap threads,
piston rod surface and inner cylinder wall
should be prevented.
In order to prevent piston rod from bending or
deformation, support it wooden block when
placing.
When removing seals, the use of sharp
tools should be avoided, so as not to stab
the seals. For the seals that are difficult to
remove, soak them with boiled water, remove
them when getting softened.
Before removing, try to create conditions
to prevent the cylinder parts from being
contaminated by the surrounding dust and
impurities. For example, try to disassemble
the equipment in a clean environment; after
the disassembly, all parts should be covered
with plastic, do not cover with cotton cloth or
other cloth used during operation;
For the cylinder which is found with internal
or external leakage during use, if the piston
rod or cylinder tube is not scratched, such
case may be due to wear or aged seals.
When the seals need to be replaced, replace
with the complete set of seals in the cylinder
repair kit.
CAUTION
- For the cylinder which is found with internal
or external leakage during use, if the piston
rod or cylinder tube is not scratched, such
case may be due to wear or aged seals (when
replacing seals, replace with the complete set
of seals in the cylinder repair kit).
Pay special attention to the cylinder tube,
piston rod and other moving parts for bumps
and scratches. If only minor damage, sand
the edge point around the damaged part with
fine stone and then polish the part smooth
with metallographic sandpaper.