New crawler tractor from Liebherr
Liebherr have added the PR 744 Litronic to their Series 4 range of crawler tractors. The new machine has been designed to increase production capacity compared with its predecessor, reduce operating costs and improve driving comfort. An important area of design was the re-engineering of the complete drive train, while maintaining the hydrostatic principle.
The engine capacity of the PR 744 Litronic has been increased by 7% to 184kW (250hp), compared with the previous model. To make optimum use of this output, the operating weight has also been increased to 28.2 tonnes.
The machine is controlled by the new fourth-generation Litronic system, which features an integral operational data memory that can be read using the multifunction display. The new Litronic system also matches the steering behaviour of the machine to the driving speed, increasing the working capacity when cornering. The PR 744 Litronic automatically uses the ‘turn the counter-rotating tracks’ function if a particularly tight turn is made.
The demand-controlled hydraulics and the float position incorporated into the single-lever controller, as well as the fast lowering function, ensure that the working equipment can be controlled quickly and precisely. Longer tracks also contribute to maximum working capacity by allowing more pulling force to be transmitted.
The PR 744 Litronic is the first Liebherr crawler tractor to be fitted with the new Liebherr D 936 L diesel engine that complies with Stage III/Tier 2 emissions regulations. The electronic engine-management system ensures that maximum torque is always available depending on the current power requirement. At the same time the combustion process is controlled so that harmful emissions are reduced.
The crawler tractor is also fitted with a new cab that features ergonomically optimized joysticks for drive and hydraulics, more space, extra storage areas, an additional cool-box container, all-round view of the working area and working equipment, and reduced noise levels.
