Komatsu PC138USLC Operation & Maintenance Manual page 352

ATTACHMENTS AND OPTIONS
Accumulator (for High Pressure)
(If equipped)
When a breaker is in use, this accumulator (5) serves to assure the
number of breaker hammering by lowering pulsation in the
hydraulic pump discharging pressure. Its another function is to
protect the pump.
Consult each manufacturer of breaker to decide if an accumulator
may well be installed on your machine.
Table for Additional Circuit and Parts Required for Mounting Breaker
( white circlet indicates an item necessary to install)
Additional filter
Hydraulic
breaker
Cracking pressure of low-pressure safety valve
Main valve 24.53 MPa (250 kg/cm
Selector valve 17.17 MPa (175 kg/cm
Breaker Circuit Additional Oil Filter
This filter (6) is used to prevent deterioration of the hydraulic oil
when using the breaker.
The oil flows through this only when the selector valve is at the
breaker position.
NOTICE
Always install an additional filter in the return circuit on machines
equipped with a hydraulic breaker.
Accumulator (for Low Pressure)
(If equipped)
This accumulator (7) is installed to protect an oil cooler, when a
breaker is used.
Consult each manufacturer of breaker to decide if an accumulator
may well be installed in your machine.
Accumulator
Attachment circuit Control circuit
(go/return)
2
, 3550.0 PSI)
2
, 2490.0 PSI)
MACHINE READY FOR ATTACHMENT
Low-pressure safety valve
Main valve Selector valve
6 - 7