National Crane 600H, Service Manual

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HYDRAULIC SYSTEM SERVICE MANUAL 600H
2-2
08-19-2022 Control # 092-13
Description Symbol
Hydraulic Reservoir - Stores, cools, and
cleans machines hydraulic fluid supply.
Hydraulic Return Lines - Terminated at (1)
below fluid level (2) above fluid level.
Hydraulic Pump - (1) fixed displacement
(2) variable displacement.
Power Source - Powers hydraulic pump
(1) combustion engine, (2) electric motor.
Hydraulic Motors - (1) unidirectional,
(2) bidirectional.
Pump Disconnect - Disconnects pump
from power source.
Continuous Line - Supply or return lines.
Connecting Lines - Branch lines
connected to main line.
Dashed Line - Pilot pressure.
Dotted Line - Case drain or load sense.
Chain Line - Enclosure of two or more
functions contained in one unit.
Pressure Transducer - Hydraulic/
electrical located in lift cylinder circuit for
cranes RCL circuit.
1 2
1
2
2
1
1
2
Filter - Removes contamination from
hydraulic fluid.
Filter with Bypass Valve - Bypass valve
allows hydraulic fluid to bypass the filter if
the filter becomes clogged.
Accumulator - Used to either develop flow
or absorb shock.
Check Valve - Creates back pressure.
Orifice - In-line fixed restriction.
Adjustable Orifice - In-line restriction used
for control device.
Hydraulic Oil Cooler - Cools hydraulic
fluid.
Temperature Switch - Regulates the
hydraulic fluid temperature.
Hydraulic Pressure Switch - Senses
hydraulic pressure to energize electrical
components.
Flow Switch - Illuminates indicator light to
indicate a fault.
Relief Valve - Protects system from being
over pressurized.
Pressure Reducing Valve - Regulates
maximum pressure.
Shuttle Valve - Used to direct maximum
pressure to components.
Description Symbol
REFERENCE ONLY