Technical description, Engine, Main winches – Liebherr LR 1280 User Manual
Page 6: Luffing jib winch, Boom winch, Swing, Crawlers, Control, Noise emission, Hydraulic system
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Engine
Power rating according to ISO 9249, 450 kW (603 HP) at 1900 rpm
Engine type
Liebherr D 9508 A7
Fuel tank
238 gal capacity with continuous level indicator
and reserve warning
Engine complies with NRMM exhaust certification EPA / CARB Tier 3 and
97/68 EC Stage III
Main winches
Line pull (1
st
layer)
max. 47,400 lbs
Line pull (7
th
layer)
33,100 lbs
Rope diameter
28 mm
Drum diameter
28.7 inch
Rope speed ft/min
0 – 453
Rope capacity in 7 layers
1,870 ft
The winches are outstanding in their compact design and easy assembly.
Propulsion is via a planetary gearbox in an oil bath.
Load support by the hydraulic system; additional safety factor provided by a
spring loaded, multi–disc holding brake.
The main winches use pressure controlled, variable flow hydraulic motors. This
system features sensors that automatically adjust oil flow to provide max. winch
speed depending on load.
Option – winch with freefall system:
Clutch and braking functions on the freefall system are provided by a compact
designed, low wear and maintenance free multi–disc brake.
Luffing jib winch
Line pull
max. 23,150 lbs
Rope diameter
20 mm
Jib luffing
51 sec. from 15º to 78º
Boom winch
Line pull
max. 48,000 lbs
Rope diameter
24 mm
Boom up
137 sec. from 15º to 86º
Swing
Consists of rollerbearing with external teeth, swing drive with fixed axial
piston hydraulic motor, spring loaded and hydraulically released multi–disc
holding brake, planetary gearbox and pinion.
Both swing modes are possible – speed control or free swing.
A multi–disc holding brake acts automatically at zero swing motion.
Swing speed from 0 – 1.8 rpm continuously variable.
Crawlers
Propulsion through axial piston motor, hydraulically released spring loaded
multi–disc brake, crawler tracks, hydraulic chain tensioning device.
Flat track shoes
47.2 inch
Drive speed
0 – 0.87 mph
Control
The control system – developed and manufactured by Liebherr – is designed
to withstand extreme environmental conditions such as temperature,
vibration and electromagnetic interference and to meet all requirements that
are needed in heavy duty crane operation.
Complete machine operating data are shown on a high resolution display.
Standard operational information is displayed by means of graphical
symbols, fault indications are displayed in plain text (more than 15 languages
available).
The cranes are equipped with proportional control for all main movements,
which can be carried out simultaneously.
The crane is operated with 2 multi–directional joysticks, the right for winch I
and boom, the left for winch II and swing control.
Option:
Bi–directional double T–levers for simultaneous boom and luffing jib
operation.
The crawlers are activated by the two central foot pedals. Additionally, hand
levers can be attached to the pedals.
Remote control for assembly of counterweight and boom hinge pins.
Noise emission
Noise emissions correspond with 2000/14/EC directive on noise emission by
equipment used outdoors.
Technical description
6
LR 1280
Hydraulic system
An axial displacement pump supplies the open loop hydraulic system for boom
luffing, jib luffing and travel. The main hoist winches and swing are operated in
a closed loop system. All functions can be operated simultaneously. To
minimize peak pressure an automatic working pressure cut–off is integrated in
a pump. All filters are electronically monitored.
The use of synthetic environmentally friendly (biodegradable) oils is possible.
Working pressure
max. 5076 PSI
Oil tank capacity
238 gal