2-32 Published 08-25-09, Control # 077-04
HYDRAULIC SYSTEM RT9130E SERVICE MANUAL
DIRECTIONAL CONTROL VALVES
Description
General
The directional control valves direct and control hydraulic oil
flow from the pumps to the boom lift and telescope cylinders,
each hoist motor, each swing motor, the counterweight
removal/cab tilt cylinders, and the front steer cylinders via
the steer control valve. The swing and front steer directional
control valve and the boom lift/telescope hoist directional
control valve are located on the outside of the right
superstructure side plate. The counterweight removal/cab tilt
directional control valve is located between the left and right
superstructure side plates forward of the hose reel. Each
valve bank is removed and installed as an assembly.
Main Directional Valve (Hoist/Telescope/Lift)
The boom lift/telescope/hoist directional control valves
(Figure 2-19) are sectional, hydraulic remote pilot actuated
three position four way, pressure compensated, closed
center directional valves. The inlet section contains a pump
unloading valve and load sense relief valve set at 3310 kPa
(4800 psi) protecting the main and auxiliary hoist sections.
The unloading valve has a 1379 kPa (200 psi) standby or
pump margin pressure setting. The telescope inner mid
section has port relief’s set a 2068 kPa (3000 psi) for extend
and 2413 kPa (3500 psi) for retract. The center mid/outer
mid telescope section has a two-stage port relief. When
unpressurized it is set for center mid cylinder extend at 1724
kPa (2500 psi). When pressurized it is set for the outer mid
cylinder at 2068 kPa (3000 psi). The retract port relief for
both the center and outer mid sections is set at 2413 kPa
(3500 psi). All working sections have a two position three
way solenoid LMI lockout valve in each pilot end cap. Both
telescope cylinder’s solenoid valves are proportionally
controlled by the LMI system.
Swing and Front Steer Directional Valve
The swing section of the swing and front steer valve
(Figure 2-18) is a sectional, hydraulic remote pilot actuated
three position four way open center directional control valve.
Both working ports have 1724 kPa (2500 psi) port relief
valves and anti void check valves to provide make-up oil to
the swing motors when the valve is centered. The steer
section is a load sense priority type flow control valve. On a
load sense signal from the cab steering control valve the
spool shifts directing 4.9 lpm (18.5 gpm) to the cab steering
control unit. The load sense port maintains a constant 862
kPa (125 psi) standby pressure. Any excess flow is directed
upstream to the swing section. The circuit is protected by a
1724 kPa (2500 psi) load sense relief valve.
Counterweight Removal/Cab Tilt Directional Control
Valve
The counterweight removal/cab tilt directional control valve
is a sectional, hydraulic remote pilot actuated three position
four way, pressure compensated, closed center directional
valve. It is plumbed in parallel with the boom lift/telescope/
hoist directional control valve. The inlet section contains a
load sense relief valve set at 1724 kPa (2500 psi) protecting
all four working sections.
Maintenance
Hoist/Lift/Telescope Directional Valve Removal
1. Tag and disconnect the hydraulic lines from the valve.
Cap or plug the lines and ports.
2. Remove the capscrews, flatwashers, and lockwashers
securing the valve. Remove the valve.
Hoist/Lift/Telescope Directional Valve Installation
1. Place the valve on the turntable upright and fasten it with
the capscrews, flatwashers and lockwashers. Torque
the capscrews 97.6 to 105.7 Nm (72 to 78 pounds-foot).
2. Connect the electrical connectors to the valve as tagged
during removal.
3. Connect the hydraulic lines to the valve as tagged during
removal.
Swing/Steer Directional Valve Removal
1. Tag and disconnect the hydraulic lines from the valve.
Cap or plug the lines and ports.
2. Remove the capscrews, flatwashers and lockwashers
securing the valve. Remove the valve bank.
Swing/Steer Directional Valve Installation
1. Place the valve on the turntable upright and secure it
with the capscrews, flatwashers and lockwashers.
Torque the capscrews 23 to 25.7 Nm (17 to 19 pounds-
foot).
2. Connect the hydraulic lines to the valves as tagged
during removal.
Counterweight Removal/Cab Tilt Directional Valve
Removal
1. Tag and disconnect the hydraulic lines from the valve.
Cap or plug the lines and ports.
2. Remove the capscrews, flatwashers, nuts and
lockwashers securing the valve. Remove the valve
bank.
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