Manitowoc 2250 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-06-15, Control # 040-13 1-75
2250 SERVICE/MAINTENANCE MANUAL INTRODUCTION
1
MAX-ER™ 2000 DESCRIPTION OF
OPERATION
MAX-ER Components
The line legend for all schematic is shown in Figure 1-45.
The MAX-ER 2000 combines a model 2250 crane with mast
and boom butt mounted load drum with a wheeled
counterweight assembly. The luffing jib attachment is also
described in this section, as it is usually part of most MAX-ER
2000’s. See Operation topic in Section 3 of MAX-ER 2000
Operator Manual for MAX-ER attachment operation
instructions or luffing jib attachment operation instructions.
The MAX-ER 2000 wheeled counterweight assembly
consists of the following components (see Figure 1-46
):
• Wheeled Counterweight Assembly - is suspended
from mast by straps and hydraulic cylinders. An arm
connects the wheeled counterweight trailer to the rear of
the crane. Trailer wheels can be turned to permit crane
travel or swing when trailer wheels are on the ground.
• Counterweight Straps and Cylinders - suspends
wheeled counterweight assembly from the mast. The
strap cylinders automatically raise and lower the
counterweight in response to changes in load (weight of
lifted load and boom angle).
• Load Sensing Pin – in the gantry left side back hitch
measures load tension created by the lifted load. The
load-sensing pin sends a proportional 0.8 to 8.0 voltage
signal to the crane PC. The crane PC enables electrical
and hydraulic systems to automatically extend and
retract the counterweight strap cylinders to raise and
lower wheeled counterweight assembly in response to
changes in back hitch tension.
• Crane Programmable Controller (PC) - controls crane
and MAX-ER systems.
• MAX-ER Programmable Controller (PC) - operates
the attachment’s electrical and hydraulic systems to
automatically raise and lower the wheeled
counterweight assembly in response to electronic
signals from the load sensing pin, pressure senders, and
cylinder limit switch.
• Strap Cylinder Limit Switch - limits how high the
wheeled counterweight assembly is raised.
MAX-ER Hydraulic Attachments
See Hydraulic Schematic in Section 2 of this manual.
Hydraulic attachments include wheeled counterweight trailer
cylinders, mast stop cylinders, jib strut cylinders, and load
drum 9 in boom butt. Hydraulic fluid to operate attachments
is from auxiliary pump on the crane. In MAX-ER mode,
hydraulic fluid to operate drum 9 system is from travel
system pumps, boom hoist charge pump and fan auxiliary
pump.
In this section a hydraulic system that is open means fluid
can flow in the circuit. Each hydraulic solenoid valve in this
manual is assigned an HS number. The HS number
identifies each hydraulic solenoid valve.
Auxiliary Pump
The main crane hydraulic tank supplies hydraulic fluid for all
attachments. The auxiliary pump draws fluid from crane
hydraulic tank through suction manifold. The current
auxiliary pump supplies pressurized hydraulic fluid between
2,200 psi (152 bar) and 2,900 psi (200 bar) to mast
accumulator system, MAX-ER accessory valve, and crane
accessory valve. The auxiliary pump pressure is monitored
and controlled by the mast accumulator pressure sender.
NOTE: Past MAX-ER’s have unloader valves that allow
hydraulic pressure up to 3,500 psi (241 bar).
Line Legend For All Schematics
High Pressure Hydraulic, Positive Electrical,
Manifold Air
Negative Electrical (Ground)
Low Pressure Hydraulic, Electrical Signal,
Exhaust Air
Control or Pilot Pressure Hydraulic,
Regulated Air
Case Return Pressure Hydraulic
Hydraulic Suction Manifold Pressure
Not Active Line or Circuit
FIGURE 1-45
HS-40 Strap Cylinders Lower (Extend)
HS-41 Strap Cylinders Raise (Retract)
HS-42 Swing/Crab - Steering Cylinder Extend
HS-43 Straight - Steering Cylinder Retract
HS-44 Left Jack Extend
HS-45 Left Jack Retract
HS-46 Right Jack Extend
HS-47 Right Jack Retract
HS-48 Center Jack Extend
HS-49 Center Jack Retract
HS-50 Tongue Cylinder Extend
HS-51 Tongue Cylinder Retract
HS-52 Steering Pins Engage
HS-53 Steering Pins Disengage
HS-54 Crawler Travel/Drum 9 Diverting
HS-55 Boom Hoist/Drum 9 Diverting
HS-56 Drum 9 Brake

Manitowoc 2250 Specifications

General

Brand	Manitowoc
Model	2250
Category	Construction Equipment
Language	English