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Maintenance
Safety, Operation and Maintenance Manual - Aug 2012
5-89
SY115C9/135C/155H Crawler Hydraulic Excavator
5.8.8.3 Nitrogen pressure in accumulator (control oil circuit) - check
Note:
In continuous operation with low nitrogen pres-
sure in the accumulator, the remaining pres-
sure in hydraulic circuit will not be released
once failure occurs to your machine.
The accumulator contains pressurized nitrogen, which may explode due to improper op-
eration, thus resulting in machine damage and personal injury. The following items must
be observed when handling the accumulator:
●
Some pressure remains in the hydraulic circuit. Never face the opening from which oil
may squirt when disassembling a hydraulic device. In addition, loosen the bolts slowly.
●
Never dismantle the accumulator.
●
Be away from
fi
re sources.
●
Never punch or weld the accumulator.
●
Never bump or roll the accumulator. Keep it free from any impacts.
●
Vent the air completely when handling the accumulator. Consult your Sany distributor
to do this job.
Functions of the accumulator
The accumulator stores the pressure of the
control circuit. Even if the engine is turned off,
the control oil circuit allows you to achieve the
following operations:
●
Operate the control lever to lower the work
equipment. The work equipment will fall
due to gravity.
●
The pressure in hydraulic circuit can be re-
leased.
The installation location of the accumulator is
shown in the right illustration.
Fig. 5-100
CZ135B-1104029
WARNING