beautypg.com

Technical description, Hydraulic system, Swing – Liebherr LB 20 User Manual

Page 11: Auxiliary winch, Crawlers, Control, Noise emission, Rope crowd system, Engine, Kelly winch with freewheeling

background image

LB 20

11

Technical description

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 63 gal/min

Separate pump for kinematics

36 gal/min

Hydraulic oil tank

159 gal

Max. working pressure

5076 PSI

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 – 3.5 rpm is continuously variable.

Auxiliary winch

Line pull effective (1

st

layer)

17.985 lbf

Rope diameter

20 mm

Line speed

0-233 ft/min

Crawlers

Propulsion through axial piston motor, hydraulically released spring
loaded multi–disc brake, maintenance-free crawler tracks, hydraulic
chain tensioning device.

Drive speed of telescopic undercarriage

0 – 1.1 mph

Track force

103,415 lbf

Width of 3-web grousers

27.6 inch

Transport width

9.8 ft


Option:
Width of 3-web grousers

31.5 inch

Transport width

11.2 ft

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/GPRS telematics module allows for remote
inquiry of machine data and operational conditions. 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.
Option:
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

67,445/67,445 lbf

Line pull (effective)

33,725 lbf

Rope diameter

24 mm

Travel

47.6 ft

Line speed

0-256 ft/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 9249, 270 kW (362 hp) at 2000 rpm
Engine type

Liebherr D 936 A7 SCR

Fuel tank

185 gal capacity with continuous level

indicator and reserve warning

Engine complies with NRMM exhaust certification EPA/CARB Tier 4i
or 97/68 EC Stage III B.

Kelly winch with freewheeling

Line pull effective (2

nd

layer)

40,465 lbf

Rope diameter

28 mm

Line speed

0-259 ft/min