Doosan powers ahead with Stage V
By Joe Sargent12 November 2019
Korean manufacturer Doosan Infracore has launched its new 36 tonne Stage V crawler excavator, the DX350LC-7.
The crawler is the first Stage V model to feature Doosan’s D-ECOPOWER technology, providing operators with higher productivity and lower fuel consumption per hour, compared with its predecessor.
As well as higher performance and cost savings, the new DX350LC-7 Stage V excavator provides a more comfortable operator environment, improved uptime and, is expected to provide a better return on investment, than the former Stage IV model.
Improved feedback to the operator through the joystick results in improved machine control and less operator fatigue. The acceleration and deceleration of the excavator workgroup functions are smoother, allowing operators to perform repetitive swinging and digging motions with less jerking movements.
The D-ECOPOWER technology focuses on the role of the hydraulics system by utilising an electronic pressure-controlled pump within a closed centre hydraulic system. This is said to accomplish a boost of up to 26% in productivity and up to 12% improvements in fuel consumption, depending on the selected mode.
In the system, a closed centred main control valve minimises pressure loss, while the electric pressure-controlled pump manages and optimises engine power more effectively. Nine sensors are used to detect the amount of hydraulic oil necessary to accomplish a specific task and precisely meter the amount of oil required rather than continuously forcing a fixed amount of oil through the system, improving efficiency.
Onboard software is utilised to electronically reproduce the full benefits of an open centre hydraulic system with lower energy losses. The hydraulic system and engine horsepower are fully optimised and synchronised, further reducing power loss within the system.
To meet Stage V engine emission regulations, the new DX350LC-7 excavator is powered by the latest generation Doosan DL08 diesel engine, providing 209 kW of power at 1800 RPM.
The new engine employed in this design is achieves its Stage V certification without the need for exhaust gas recirculation (EGR). Without EGR the quantity of air available during combustion is greater in volume, increasing the temperature of the process and greatly reducing the amount of particulates produced. This, combined with diesel oxidation catalysts (DOC), diesel particulate filters (DPF) and selective catalytic reduction (SCR) after-treatment technology ensures reduced emissions.
Service intervals for the DPF have also been reduced, with no maintenance required until the machine has operated for 8000 hours.