New Doosan wheel loader
Doosan continue to extend and enhance their range of large wheel loaders with the launch of the new DL420, which succeeds and replaces the DL400. With a bucket capacity of 4.0m3, the DL420 is designed to offer improved performance in terms of ease of handling, power, serviceability and durability. It is intended to meet a wide range of material-handling needs from loading and transporting granular material (such as sand and gravel), to industrial, mining and quarrying applications.
With the addition of the DL420, the Doosan range of articulated wheel loaders includes eight models with bucket capacities from 1.5m3 to 5.0m3. Key features offered by the DL420 include more productivity at lower cost, reliability, comfort and ease of maintenance.
The 22.3-tonne DL420 is powered by the 10.8-litre, six-cylinder turbocharged Cummins QSM11 electronically-controlled engine with high-pressure unit injector system and a state-of-the-art combustion system. Emissions are well below phase III regulatory limits and fuel consumption is about 7% less when compared to the DL400.
The engine develops 209kW (284hp) at 2,000 rev/min and offers a maximum torque of 148kg.m at 1,400 rev/min, for optimal traction and breakout force in loading-transport-handling applications.
Breakout force is 210kN, an important feature for a machine of this Z kinematic class, providing a higher stripping force when working in the hardest materials.
Two working modes (standard and economical) are available to optimize the consumption/productivity ratio and adapt the loader to the work at hand.
There are four forwards travel speed ranges with maximum speeds of 6.5km/h, 12.4km/h, 18.4km/h, and 38km/h and three backwards travel speed ranges with maximum speeds of 6.5km/h, 12.4km/h and 18.4km/h. The Cummins engine allows the DL420 to reach 90% of the maximum speed in 2.3 seconds. The larger engine is also designed to provide increased durability and a longer service life.
The DL420 offers a static tipping load with a bucket of 18.9 tonnes (at maximum reach with a straight frame) and a height at bucket pivot point of 4.35m. Equipped with a pin-on bucket with teeth and tipped forward at 45 degrees, the dump height is 2.96m and the dump reach is 1.40m. The turning radius at bucket edge is 6.995m at the maximum steering angle of 40 degrees.
The DL420 uses a Powershift ZF transmission with limited slip differentials. The primary brakes are hydraulically controlled, multi-disc wet brakes.
In order to ensure a long service life to the main structural components, including the chassis, lift arms and articulations, Doosan use finite element methodology and state-of-the-art computer-aided design techniques. Using computerized modelling, they are subjected to intensive laboratory and field tests in which extreme conditions are simulated and tested.
Improved visibility, heating and air conditioning, more room, a comfortable seat, and ample storage space are all features that allow operators to work for more hours with less fatigue. The noise level in the cab is a comfortable 71.2dB(A) while the external sound level is 104.7LwA.
New features contributing to operator convenience include an integrated monitoring system, vehicle control unit (VCU) and an optional electric steering system. The integrated LCD panel displays information about the loader, engine and transmission, including the service intervals for each filter and the engine oil. The transmission can be tuned by the operator without the assistance of a mechanic. The VCU optimizes performance by controlling engine, transmission and hydraulic system variables.
Other features contributing to operator comfort and convenience are a third hydraulic control valve to use the most complex attachments and anti-pitch control. Available as an option is a system using a single lever for the control of travel functions and front-mounted attachments.
The DL420 wheel loader is designed to be economical in both use and maintenance. To reduce fuel consumption and noise, the variable-speed fan is controlled by a thermostat. The fan is reversible and tilts in order to facilitate maintenance in dusty environments. There are also large covers for service access from the ground.
Intervals between oil changes and filter replacement have been lengthened, as for the other Doosan loaders. Transmission status is easily verified and various adjustments such as compensation for disc wear are done automatically with no disassembly required.