Manitowoc Grove YB5515 Service Manual

GROVE Published 10-21-2010, Control# 198-04 10-1
5540F/YB5515 SERVICE MANUAL STEERING SYSTEM
10
SECTION 10
STEERING SYSTEM
UNITS WITHOUT RETURN-TO-CENTER STEERING
TECHNICAL DATA
Rated pump output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 gpm at 2500 rpm (20,8 l/min at 2500 rpm)
Relief valve setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2500 ±50 psi at 2500 rpm (17 225 ± 345 kPa at 2500 rpm)
DESCRIPTION
The crane can be operated in three steering modes. These
modes are selected using the steering selector switch
located to the left of the operator on the side instrument
panel. The three modes are:
• Two-wheel steering
• Four-wheel steering
• Crab steering
Two-Wheel Steering
During two-wheel steering, the rear wheels steer in the
opposite direction that the steering wheel turns. The front
wheels remain in a fixed forward position.
When turning to the right Figure 10-1, hydraulic oil under
pressure from the steering pump flows to the steering orbitrol
in the operator’s compartment. When the steering wheel is
turned to the right, hydraulic fluid is directed through port R of
the steering orbitrol to port C1 of the rear steering solenoid
valve. The rear steering solenoid valve is not energized in
two-wheel steer mode, therefore the hydraulic oil flows out
Port V1 to the rod end of the left rear steering cylinder and
the base end of the right rear steering cylinder. The left
cylinder rod retracts and the right cylinder rod extends,
turning the rear wheels to make a right turn. Return oil from
the rear steering cylinders flows back to tank through Ports
V2 and C2 of the rear steering solenoid valve, Ports C2 and
V1 of the front steering solenoid valve, Ports L and OUT of
the steering orbitrol.
Four-Wheel Steering
During four-wheel steering, the front wheels steer in the
direction that the steering wheel is turned, while the rear
wheels turn in the opposite direction. This mode provides an
extremely short turning radius. It allows the rear wheels to
follow the track of the front wheels, which is an advantage in
muddy or sandy conditions.
When turning to the right Figure 10-2, hydraulic oil under
pressure from the steering pump flows to the steering orbitrol
in the operator’s compartment. When the steering wheel is
turned to the right, hydraulic fluid is directed through port R of
the steering orbitrol to port C1 of the rear steering solenoid
valve. The rear steering solenoid valve is not energized in
four-wheel steer mode, therefore the hydraulic oil flows out
Port V1 to the rod end of the left rear steering cylinder and
the base end of the right rear steering cylinder. The left
cylinder rod retracts and the right cylinder rod extends,
turning the rear wheels to make a right hand turn. Oil under
reduced pressure from the rear steering cylinders flows back
through Ports V2 and C2 of the rear steering solenoid valve
to Ports C2 of the front steering solenoid valve. In four-wheel
steer mode, the front steering solenoid valve is actuated and
oil flows through Ports C2 and V2 to the rod end of the left
front steering cylinder and the base end of the right front
steering cylinder. The left front cylinder rod retracts while the
right front cylinder rod extends, turning the wheels to make a
right turn. Return oil from the steering cylinders flows back to
tank through Ports C1 and V1 of the front steering solenoid
valve and Ports L and OUT of the steering orbitrol.
Crab Steering
During crab steering all the wheels steer in the same
direction. This mode allows the operator to move the
machine sideways. This is especially helpful in tight areas on
the job.
Reference Only

Manitowoc Grove YB5515 Specifications

General

Brand	Manitowoc
Model	Grove YB5515
Category	Construction Equipment
Language	English