A world premiere at Munich, the Doosan wheel loader: the 14.5 tons DL250.

Bauma 2007: Following the line of top models in the range, which have already been extremely successful in Europe, Doosan is starting the renewal of its smaller wheel loaders by introducing the DL250.

A few key words sum up the care and attention exercised by Doosan in the development of this new loader: greater performance, first class comfort, excellent reliability and ease of maintenance.

The Engine and performance

This new Doosan DL250 loader is powered by the Doosan DL06 engine, developed with a net nominal power of 165 HP (121 kW). This turbo charged common rail engine is equipped with air to air inter-cooling, 4 valves per cylinder and exhaust gas recirculation, which help to ensure that the emissions generated are significantly lower than the limits stipulated by the Phase III regulations.

This engine offers 9% more torque than the engine of the Mega 250-V which it replaces, resulting in better responsiveness of the engine and, ultimately, in a shorter cycle time for the machine.

This engine is equipped with an electronic control system making more precise adjustment possible as well as offering two operating modes: standard and economy for lighter work. The electronic control system can also facilitates the diagnostics in the case of breakdown.

The standard bucket capacity has been increased at the same time.

The Cabin and driving comfort

With the importance of the operator’s well being in mind, Doosan has provided a first class operating area. In comparison with the old Mega 250-V, there is no less than 15% more space and 20% greater visibility for the operator.

The visibility has been increased by repositioning the operator’s seat and increasing the surface area of the windscreen, and t he new fluid and rounded lines of the back cover also result in better visibility to the rear.

Access to the machine is easy thanks to a door that now opens 180° and inclined steps. Once installed in the comfortable seat, which is provided with numerous adjustment options, and the angle & height of the steering wheel has been set the operator is in the ideal operating position to allow him to safely & comfortably operate the machine, regardless of his build.

The ventilation has also been strengthened by increasing the number of ventilation outlets. The noise level in the cabin has been greatly reduced by optimising numerous elements: notably, the exhaust and the machine cooling fan, which is now speed controlled dependent on the machines operating temperatures. The noise in the cabin is only 72 dB(a).

The DL250 is easy to drive. The bucket and lifting may be controlled either by a mono lever with an integrated forwards and reverse control or a system of multiple “finger type” levers. The third hydraulic function is standard.

Gears can be selected manually or automatically with a manual kick-down facility. The operator can select between two different automatic settings, for normal use 2 nd, 3 rd and 4 th gears only are used, with manual kick down allowing use of 1 st gear, but for some very heavy applications use of all 4 gears without manual intervention can be selected.

The bucket suspension system was also revised to offer excellent driver comfort even with an empty bucket thanks to a new suspension valve and accumulator.

Reliability and maintenance

Doosan uses top quality elements. This was a basic instruction, which the designers took into account throughout the development phases.

Doosan engines are renowned for their reliability as are the ZF transmission and axles used.

But Doosan wants to go even further. All the structural elements, such as the chassis for example, have been reviewed using finite element three-dimensional analyses and, if necessary, reinforced in order to increase the machine’s life span. Detailed analyses has also been carried out on numerous elements, and these various elements were then tested in the laboratory and in the field and then, if necessary, modified to increase their reliability.

The tolerances in relation to the machine construction have also been greatly improved to limit some movements, that in time that may result in premature wear and tear. Elements have also been reinforced.

The periodic servicing of the machine has been reduced by half which is equivalent to hundreds of hours’ work during the machines life. For example, the engine oil change frequency is now every 500 hours and 2,000 hours in the case of hydraulic oil.

To achieve this, different elements had to be improved such as the capacity and quality of some filters. The air filter now has double the life span and some elements have been added like a pre-filter on the primary fuel pump or a water-separating filter for the fuel.

The materials for all the pins (buckets, boom and cylinders) have been improved to reduce the time required for lubrication.

In order to reduce clogging in the radiator in dusty environments and to facilitate its maintenance, a reversible fan motor is now fitted.

In conclusion, the Doosan DL250 machine has been completely rethought and has benefited from all the experience in the field contributed by the operators and all the maintenance staff.

The DL 250 offers the user maximum performance, comfort and reliability. It includes excellent added value.

Key to the illustrations

1. DL250 at work
2. Cabin
3. DL06 Engine
4. View of the chassis per finished element

For more information concerning this press release, please contact:

Virginie Pauly
Construction Equipment Marketing Assistant