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Section H Steering
9803/7130
Section H
3 - 2
Issue 1
Basic System Operation
Hydraulic Operation
The main components of the steering system are the priority
valve A, load sensing steer unit B, hydraulic tank C, front
steer ram D and rear steer ram E and steer setting valve F.
When the steering wheel is turned, a pressure demand is
sensed at the priority valve A via load sensing line LS.
Oil from the hydraulic pump G is then distributed via the
priority valve to the steer unit B.
When left turn is selected, oil is distributed from steer unit B
to the rear steer ram E. When right turn is selected, oil is
delivered to the front steer ram D.
When the steering lock is held, the pressure signal LS
ceases, flow from the hydraulic pump is now distributed to
the main hydraulic circuit via the priority valve A.
Maximum steering system pressure is controlled by a relief
valve located in the steering unit B.
DD
EE
FF
AA
GG
CC
LS
BB
AA
FF
BB