Manitowoc 2250 Service Maintenance Manual

Reference Only
Manitowoc Published 07-19-16, Control # 249-01 1-61
2250 SERVICE/MAINTENANCE MANUAL INTRODUCTION
1
Lower Accessory System Components
General
The lower accessory system components include the boom
hinge pin cylinders, boom handling cylinders, rigging winch
motor, and crawler pin cylinders. During normal operation
the lower accessory solenoid valves are “motor spooled,”
where both cylinder ports and tank port of the valve spool
section are connected in the center position and open to the
tank.
The auxiliary pump is the hydraulic pressure source to
operate the upper and lower accessory system components.
Hydraulic fluid from the auxiliary pump flows through the
auxiliary system’s disable-relief valve HS-12. Hydraulic fluid
enters the upper accessory valve and flows through the
variable output control valve HS-20 and hydraulic quick
disconnect to the lower accessory valve.
The auxiliary system’s disable-relief valve HS-12 is
controlled by the PC. During normal operation the relief valve
is open and excess fluid from the auxiliary pump is dumped
through the valve to the tank. When a component of either
accessory system is enabled, an input signal is sent to the
programmable controller (PC). The PC sends a 12 V output
signal to the auxiliary system’s disable-relief valve HS-12
that adjusts system pressure to 276 bar (4,000 psi).
When a lower accessory system switch is enabled, the PC
sends a variable 0 to 12 V output signal to the variable
output control valve HS-20. The variable-control valve output
is adjustable from 0 to 57 L/min (0 to15 gpm) with the speed
control rotary switch on the setup remote control.
Boom Hinge Pins
See Figure 1-36 and Figure 1-37 for the following.
Boom hinge pins cannot be disengaged until the cylinder
lock cover on the front of the rotating bed is open.
With the engine running, power is available to the setup
remote control when the cable is connected at the air valve
junction box on the left side of the rotating bed.
Boom Hinge Pins Engage
When the power button is pressed and the boom hinge pins
switch is held in the DOWN (engage) position, an input
signal is sent to the PC. The PC sends a 12 V output signal
to the auxiliary system’s disable-relief valve HS-12 that
adjusts system pressure to 276 bar (4,000 psi).
The boom hinge pins engage solenoid HS-10 and are
enabled by the PC to shift the solenoid valve in the engage
position. Hydraulic fluid enters the upper accessory valve
and flows through the variable output control valve HS-20
and hydraulic quick disconnect assembly to the lower
accessory valve.
Hydraulic fluid exits the valve assembly and flows to the
piston end of the hinge pin cylinders, engaging the pins to
connect the boom to the adapter frame. Fluid from the rod
end of the cylinders flows through the valve assembly
through the hydraulic quick disconnect and to the tank.
When the power button or boom hinge pins switch is
released, the PC sends a 0 V output to shift the spool of
solenoid HS-10 to the center position.
Boom Hinge Pins Disengage
When the power button is pressed and the boom hinge pins
switch is held in the UP (disengage) position, an input signal
is sent to the PC. The PC sends a 12 V output signal to the
auxiliary system’s disable-relief valve HS-12 that adjusts the
system pressure to 241 bar (3,500 psi).
The boom hinge pins engage solenoid HS-11 and are
enabled by the PC to shift the boom hinge pin solenoid valve
in the disengage position. Hydraulic fluid enters the upper
accessory valve and flows through the variable output
control valve HS-20 and hydraulic quick disconnect
assembly to the lower accessory valve.
Hydraulic fluid exits the valve assembly and flows to the rod
end of the hinge pin cylinders, disengaging the pins from the
boom and adapter frame. Fluid from the piston end of the
cylinders flows through the valve assembly through the
hydraulic quick disconnect and to the tank.
When the power button or boom hinge pins switch is
released, the PC sends a 0 V output to shift the spool of
solenoid HS-10 to the center position.

Manitowoc 2250 Specifications

General

Brand	Manitowoc
Model	2250
Category	Construction Equipment
Language	English