Axle Oscillation Lockout Valve; Description; Maintenance - Manitowoc Grove RT765E-2 Service And Maintenance Manual

RT765E-2 SERVICE MANUAL

AXLE OSCILLATION LOCKOUT VALVE

Description

The axle oscillation lockout valve Figure 2-31(also called the
double solenoid valve) is used in the rear axle oscillation
lockout circuit. The valve is mounted on the left rear face of
the carrier frame rear cross member forward of the rear axle.
It consists of a valve body and two normally-closed, two-way,
two-position solenoid valves. It keeps the lockout cylinders
from oscillating unless the turntable is centered forward.
For the CE units with dual axis controllers, the axle oscillating
lockout valve is replaced with four two way solenoid
operated poppet cartridge valves installed in the ports of the
lockout cylinders.
An angle encoder located in the top of the electrical slip ring
assembly sends a CAN bus message to the RCL. The RCL
converts the data in the message to a position angle of the
superstructure relative to the carrier (slew angle). If the slew
angle is ±2° of directly over the front, the RCL sends a CAN
bus message to the Crane Control System to allow axle
oscillation. When the Crane Control System receives this
message it switches ON a digital output thus energizing the
axle oscillation solenoids. If the angle is more than 2° left or
2° right of directly over the front, the Crane Control System
switches OFF the digital output thus de-energizing the axle
oscillation solenoids.
When the axle oscillation normally closed solenoid valves
are de-energized the lockout cylinders are isolated from
hydraulic oil supply. This keeps the cylinders from oscillating
(moving up and down to damp axle movement) because
1
Item
Port B - To Right Hand Rear Axle Lockout
1
Cylinder
2 Port C - From Pump # 1, Section 2
GROVE
2
3
7543-2

Description

Published 9-04-2014, Control # 422-08
hydraulic oil cannot leave the cylinders. Instead, the
cylinders remain full of hydraulic oil and more rigid.
When the axle oscillation solenoid valves are energized and
open, hydraulic oil is allowed in and out of the cylinders,
allowing them to oscillate.

Maintenance

Removal
1. Tag and disconnect the electrical connectors to the
valve.
2. Tag and disconnect the hydraulic hoses from the valve.
Cap or plug the lines and ports.
3. Remove the hex nuts, capscrews and washers securing
the valve to the frame bracket. Remove the valve.
Installation
1. Secure the valve to the crane with the washers,
capscrews and hex nuts. Torque capscrews; refer to
Fasteners and Torque Values, page 1-16 for proper
torque value.
2. Connect the hydraulic hoses to the ports on the valve as
tagged during removal.
3. Connect the electrical connectors to the valve as tagged
during removal.
4. Verify proper operation. Refer to Proper Operation Of
Axle Oscillation Lockouts in Section 3 of the Operator's
Manual.
5. Check valve and hoses for leaks. Make repairs as
needed.
1
2
7543-1
Item
3 Port A - To Left Hand Rear Axle Lockout Cylinder
HYDRAULIC SYSTEM
3
FIGURE 2-31
Description
2
2-53