Komatsu PC450-8, Operation & Maintenance Manual

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HIGH REACH DEMOLITION EQUIPMENT 27M
PURGING AIR PROCEDURES
7-41
PURGING AIR PROCEDURES 7
PURGING PROCEDURE TO REMOVE AIR FROM HYDRAULIC CYLINDER
LINES.
7
NOTICE
Follow this procedure whenever hydraulic circuits have been disconnected and reconnected.
1. Run the engine at low idle speed to extend and retract the cylinder 4 to 5 times. For both extension and
retraction, stop the cylinder approximately 100mm before the end of the stroke.
2. In addition extend and retract the cylinder to the stroke ends 3 to 4 times.
3. Again extend and retract the cylinder 4 to 5 times to the stroke ends to completely purge air from the hydraulic
circuit.
4. On completing these operations, run the engine at normal speed.
PROCEDURE FOR PURGING AIR FROM BOOM LOCK VALVE PPC
CIRCUIT
7
WARNING
While monitoring oil temperature, loosen the cap of the
hydraulic oil tank to release residual pressure (purge air) in
the tank.
1. PRECAUTIONS FOR PURGING AIR FROM BOOM LOCK
VALVE PPC CIRCUIT.
1. To mount the demolition high reach boom and arm, purge air
from the boom lock valve PPC circuit before operating the cyl-
inder.
2. To assemble the demolition high reach work equipment,
purge air from the boom lock valve PPC circuit before the cyl-
inder rod side work equipment is mounted.
3. To remove the PPC circuit hoses, stop the engine and oper-
ate the control levers and pedals to release residual pressure
in the circuit.
4. For safety, during air purging, close the stop valve in the work
equipment piping.
Cylinder rod side
Cylinder bottom
bracket side
Boom lock valve