Innovative Technologies Liebherr

The design and innovative technologies allow the Liebherr PR 734 Litronic crawler bulldozers to cope with layer-by-layer soil displacement or surface planning, and in coal mines these machines are used for loosening of overburden, preparation of excavator sites, construction and cleaning of roads.

The guarantor of the outstanding operational qualities of the "German" is, first of all, the advanced solutions implemented in the creation of the engine-transmission part and the control system. "Heart" of the bulldozer is the company's 6-cylinder diesel Liebherr D 936-L A6, which, with a working volume of 10.5 liters, develops 204 liters. from. The engine is designed for extreme conditions and at the expense of working at a reduced speed provides high reliability, economy and motor resources. The fuel injection system type PLD (pump-tube-injector), four valves per cylinder, a turbocharger with cooling air injection and electronic control of the working processes provide a sufficient reserve of power to work in any situation. The friendliness of the motor to the environment corresponds to the current environmental standards.
The forced lubrication system under pressure and the crankcase of increased depth ensure the reliable operation of the bulldozer engine when driving along slopes steepness up to 45 °. The updated electronic control system Litronic in addition to the traditional function of protecting the motor from overloads by automatically maintaining a balance between speed and tractive effort controls the deviation from operating parameters and computer diagnostics of malfunctions.

Continuous hydrostatic transmission with separate independent drive of tracks does not have a number of components that are traditional for many bulldozers, such as torque converter, gearbox, differentials, friction clutch . With this drive, the PR 734 Litronic performs equally confidently the working operations, moving both forward and reverse. The electronic system Litronic continuously adjusts the speed of the tracks (in the range from 0 to 11 km / h) and torque, optimizing the tractive effort depending on the changing external load.

The machine is able to move along any curvilinear trajectory and unfold on the spot around its geometric center. The reinforced side reducers are distinguished by their high endurance. Double gliding seals with automatic tightness control ensure their reliable protection. Optimal regulation of the engine, hydraulic pump and hydraulic motors of the transmission reduces fuel consumption even under the most stressful operating conditions. The parking brakes in the onboard gearboxes that are automatically switched on when the machine is stopped provide additional safety. The Liebherr PR 734 Litronic load-bearing frame is made of high-profile box-section profiles, which ensures a high strength of the structure for bending and torsion. In this case, the most critical elements are made in the form of cast parts. Modifications to the bulldozer, L, XL and LGP, differing in the dimensions of the running trolley (as well as the length and width of the caterpillar propulsors) are designed to work on surfaces with different bearing capacity (loose soil, rock, marshy terrain, etc.). All varieties PR 734 Litronic can be equipped with bulldozer dumps and rippers of several types. The quick-change adapter for the work equipment reduces the time for installing and dismounting the dumps up to several minutes.

Comfort and ergonomics

The cab of the Liebherr PR 734 Litronic can be envied by many competitors. Its trump cards are elastic suspension, impressive internal volume, impressive area of tinted glazing, side sliding windows, efficient windshield wipers and powerful outdoor lighting. The integrated safety cage provides reliable protection in case of tipping (ROPS standard) and falling objects (FOPS standard). Due to the enhanced soundproofing, the noise level in the cabin does not exceed 78 dB (A), which is noticeably lower than prescribed by legislative requirements. The place of the operator bribes exemplary ergonomics and comfort, which, undoubtedly, creates the conditions for productive work. A comfortable chair with individual suspension, seat belts, a variety of adjustments to the position of the pillow and backrest, and adjustable head restraints and armrests will impress any user. All instrumentation and controls are in the best viewing zone and are easily accessible. On the combined instrument panel, analogue indicators and safety devices are logically arranged, as well as a liquid crystal display, which displays many diagnostic parameters and performance indicators of the main systems of the bulldozer. With the help of a single joystick, the operator can easily control the forward and reverse, as well as curvilinear movement, including a turn in place. Another joystick serves to control the working equipment (blade and ripper). Comfortable microclimate in the cabin provides high-performance ventilation and heating systems, and if necessary air conditioning. You can not also fail to note the quality plastic used in the interior decoration, and a roomy storage box with an electrical connector with a voltage of 12 V for connecting a mini fridge. For ease of maintenance, the bulldozer cab can be folded back by an angle of 40 'with the built-in manual hydraulic jack . For the same purpose, all control points of the engine systems are located on one side.