Technical data, Hydraulic system, Swing – Liebherr LRB 255 User Manual
Page 5: Auxiliary winch, Crawlers, Control, Noise emission, Rope crowd system, Engine, Main winch with freefall

LRB 255
5
Technical data
Hydraulic system
The main pumps are operated by a distributor gearbox. Axial piston
displacement pumps work in open circuits supplying oil only when
needed (flow control on demand).
The hydraulic pressure peaks are absorbed by the integrated
automatic pressure compensation, which relieves the pump and
saves fuel.
Pumps for working tools
2x 400 l/min and 1x 350 l/min
Separate pump for kinematics
129 l/min
Separate pump for crowd system
300 l/min
Hydraulic oil tank
1000 l
Max. working pressure
350 bar
No auxiliary power packs are required as application specific
hydraulics supply power to all components.
The cleaning of the hydraulic oils occurs via an electronically
monitored pressure and return filter.
Any clogging is shown on the display in the cab.
The use of synthetic environmentally friendly oil is also possible.
Swing
Consists of triple-row roller bearing with external teeth and two
swing drives, fixed axial piston hydraulic motor, spring loaded and
hydraulically released multi–disc holding brake, planetary gearbox
and pinion. Selector for 3 speed ranges to increase swing precision.
Swing speed from 0 – 4.5 rpm is continuously variable.
Auxiliary winch
Line pull (effective)
80 kN
Rope diameter
20 mm
Drum diameter
320 mm
Line speed
0 - 48 m/min
Crawlers
Propulsion through axial piston motor, hydraulically released spring
loaded multi–disc brake, maintenance free crawler tracks, hydraulic
chain tensioning device.
Drive speed
0 – 1.5 km/h
Track force
622 kN
Width of 3-web track shoes
900 mm
Control
The control system – developed and manufactured by Liebherr – is
designed to withstand extreme temperatures and the many heavy–
duty construction tasks for which this machine has been designed.
Complete machine operating data are displayed on a high resolution
monitor screen. A GSM modem allows for remote inquiry of machine
data and error indications. To ensure clarity of the information on
display, different levels of data are shown in enlarged lettering and
symbols.
Control and monitoring of the sensors are also handled by this high
technology system. Error indications are automatically displayed on
the monitor in clear text. The machine is equipped with proportional
control for all movements, which can be carried out simultaneously.
Two joysticks are required for operation. Pedal control can be
changed to hand control.
Options :
PDE : Process data recording
Noise emission
Noise emissions correspond with 2000/14/EC directive on noise
emission by equipment used outdoors.
Rope crowd system
Crowd force push/pull
450/450 kN
Line pull (effective)
150 kN
Rope diameter
24 mm
Line speed
0 - 87 m/min
The winches are noted for compact, easily mounted design.
Propulsion is via a maintenance-free planetary gearbox in oil bath.
Load support by the hydraulic system; additional safety factor by
a spring–loaded, multi–disc holding brake. All line pull values are
effective values. The efficiency factor of approx. 25% has already
been deducted.
Engine
Power rating according to ISO 3046, 670 kW (898 hp) at 1900 rpm
Engine type
MAN D 2842 LE
Fuel tank
795 l capacity with continuous level
indicator and reserve warning
Engine complies with NRMM exhaust certification EPA/CARB Tier 2.
Main winch with freefall
Line pull (effective)
200 kN
Rope diameter
30 mm
Line speed
0 - 89 m/min