Manitowoc 999, Service And Maintenance Manual

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Reference
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INTRODUCTION 999 SERVICE/MAINTENANCE MANUAL
1-42
Published 05-16-17, Control # 233-03
CRANE SETUP SYSTEMS
See Figure 1-31
Place and hold crane mode switch in select position until the
crane setup mode is displayed. Next, turn crane mode switch
to confirm position to select and lock-in crane setup mode.
The PC locks-out other mode selections and enables the
boom hoist system, rear drum system, upperworks
accessory valve system, and the lowerworks accessory
valve system.
When an accessory valve is enabled, the low-pressure side
of the rear drum pump (5) is the pressure source to operate
upperworks accessory valve manifold (3) and lowerworks
accessory valve manifold(4).
Upperworks accessory valve manifold contains three
solenoid valves and a mast bypass valve (1). The solenoid
valves are piped in parallel but can be controlled
independently for simultaneous accessory operation. The
crane has direct-acting solenoids and do not require the
reducing valve to supply pilot pressure for shifting the spools.
Upperworks accessory valve system includes boom pin
pusher cylinder (7), gantry cylinders (8), and mast raising
cylinders (9) that are electrically enabled. When an
upperworks accessory valve is electrically enabled, an
output signal is sent from the PC to the solenoid valve for the
selected component, shifting its main spool. The PC sends a
negative output voltage to stroke low-pressure side of rear
drum pump to enable the selected accessory valve
component.
Low-pressure side of rear hoist drum motor pressure sender
(14) monitors accessory system pressure. The PC looks at
the accessory system pressure sender and holds the system
to required accessory pressure (see
Figure 1-30
) by
controlling pump stroke. The rear hoist pump’s multifunction
valve of the low pressure side, port “B”, is the accessory
system safety delta pressure across the pump of 3770 (260
BAR).
The lowerworks accessory valve system includes crawler pin
pusher cylinders (10) and carbody jack cylinders (11) that are
enabled by return-to-center hand levers. Output flow from
the lowerworks accessory system passes through control
levers when all of the levers are centered. An orifice (13)
restricts the flow, building pressure in the line that closes the
accessory pressure switch (12). The PC then knows that
none of the lowerworks accessory levers are enabled. When
a lever is manually enabled, the flow is diverted from the
switch to the desired accessory system. The pressure at the
switch bleeds away through the orifice and the accessory
pressure switch opens. The PC then sends a negative
voltage to the rear drum to increase the pressure to the
selected accessory system component. Accessory pressure
switch trips at 120 psi (8,3 bar). The PC monitors lowerworks
accessory system pressure and holds the system to 3000 psi
(207 BAR) by controlling pump stroke.
CAUTION
The boom must not be operated in Crane Setup mode for
normal operation. The PC assumes that crane is in mast
r a i s i n g p r o c e d u r e a n d b o o m p e r f o r m a n c e i s
unpredictable. Select and confirm Full Power mode after
crane set-up is complete.
CAUTION
Mast bypass valve (1), in right side enclosure, must be
turned to ON position during crane setup (assembly and
disassembly). Mast bypass valve must be turned to OFF
position during normal operation to prevent mast arms
from raising and contacting mast.
Item Accessory System Pressure Requirement PSI BAR
1 Raising Mast With Gantry Cylinders 1550 107
2 Lowering Mast With Gantry Cylinders 3500 241
3 Raising Counterweight With Gantry Cylinders 3800 262
4 Lowering Counterweight With Gantry Cylinders 3000 207
5 Raising Mast With Mast Cylinders 3000 207
6 Lowering Mast With Mast Cylinders 700 48
7 Extend Mast Arms Only 2000 138
8 Retract Mast Arms Only 2500 172
9 Boom Hinge Pin (Extend and Retract) 3000 207
10 Counterweight Pins 350 24
FIGURE 1-30