New Holland Workmaster 75, Руководство по обслуживанию

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HYDRAULIC - PNEUMATIC - ELECTRICAL - ELECTRONIC SYSTEMS - PRIMARY HYDRAULIC POWER
SYSTEM
PRIMARY HYDRAULIC POWER SYSTEM - Component identification
Introduction and circuit identification
The hydraulic system on the WORKMASTER 75 tractor
is for mechanical lift assembly to raise and lower the lift
arms in turn three point linkages and for remote control
valves.
The high pressure hydraulic circuit is of open center load
sensing type.
In this system, hydraulic lift and remote control valve are
connected in series and pump flow is continuously circu-
lating through the hydraulic system even when the circuit
are not being operated.
The priority of operation is given to the order of compo-
nents in the circuit, that is remote valves and hydraulic
lift. This means for example when fully operating a re-
mote valve the lift will not operate at the same time.
The open center high pressure hydraulic circuit with me-
chanically controlled hydraulic lift is shown in
PRIMARY
HYDRAULIC POWER SYSTEM - Hydraulic schema
(A.10.A)
and includes the components shown in the
Remote control valve - Static description (A.10.D)
and PRIMARY HYDRAULIC POWER SYSTEM - Static
description (A.10.A) .
Pump
Open center hydraulic pump assembly is a high pressure
gear pump,
(1) . See Hydraulic pump - Static descrip-
tion (A.10.A) of this Section for more details on pump.
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Filter
Full-flow spin on type filter, (1) , directly mounted on suc-
tion side of the pump.
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A.10.A / 9