New-generation compact excavators from Doosan
Doosan have launched two new-generation 6-tonne compact excavators - the new DX62R-3 reduced tail swing (RTS) and DX63-3 conventional tail swing models.
Designed as replacements for the existing DX60R and DX55E machines, the new models incorporate advances in a number of areas to maximize performance, versatility, operator comfort, durability, ease of maintenance and serviceability with minimum impact on human health and the environment.
One of the features on the new 6-tonne excavators is the increase in hydraulic performance, which has been boosted with a 33% increase in maximum flow rate to 132 litres/min. In addition, the hydraulic system now incorporates a load-sensing system which is said to guarantee high hydraulic performance and allows smooth and efficient combined operations. Two-way auxiliary hydraulic flow is also available for the primary auxiliary circuit for operating high-flow attachments.
This is complemented by a significant increase in the digging forces - the bucket digging force is now 4.4 tonnes, 7% above the previous models, and the arm digging force is 10% higher at 2.9 tonnes. This is combined with a longer arm for a better overall working range. The traction force has also been increased by 5% to 5.6 tonnes and travel speeds have been increased in both the low range (2.6km/h) and the high range (4.7km/h).
High-comfort cab
The space available in the new ROPS operator cab is similar to that found on much larger medium- and heavy-duty machines.
The cab, which has a large entrance and exit, offers a low noise level of 73 dBA. A high capacity heating and air conditioning system is fitted as standard, with fully adjustable vents installed at both the front and rear of the operator's seat to maximize efficiency.
The interior of the cab has been ergonomically designed to optimize operator comfort and features an increased foot rest area and an additional cup holder. The openness of the cab provides a wide field of view and good all-round visibility. The cab lighting, sun visor and side mirror all contribute to a safe and pleasant working environment for the operator.
The position and angle of the seat cushion, as well as the position of the consoles, can be adjusted to suit the operator. Additional comfort is provided by the seat back pocket and the lumbar support. A seat heater is available as an option.
Both new excavators are designed for easy, precise controllability with the left and right control stands ergonomically placed for convenient operation. The proportional hydraulic joystick levers have comfortable grips that allow the operator to perform smooth, precise actions.
A new full-colour 5.7in LCD monitor allows operators to control auxiliary flow and to monitor functions such as service periods. The control panel provides comprehensive information about the status of the machine. There is also an anti-theft protection via a password lock-out system.
Hydraulic flow control is provided via roller software for control of auxiliary hydraulic flow (Aux1/Aux2), boom swing (offset) and tilting operations. In addition, auto down shift and dozer float levelling functions are all now available on the new models.
Safety features included as standard include lock valves on the arm and the boom cylinders and an overload warning device. Other standard features include an electric refuelling pump and a defroster for the windscreen.
The DX62R-3 and the DX63-3 models are powered by Stage IIIA compliant 36.2kW liquid-cooled Yanmar 4TNV94L diesel engines running at a maximum speed of 2,200 rev/min. Electronic injection together with automatic idle ensures optimum fuel efficiency at all times.
The low noise and emission levels of both models ensure they are suitable for operation in noise-sensitive areas and at night.
Easy maintenance
The advanced technology used in the DX62R-3 and DX63-3 excavators complements the powerful performance with simple, easy-maintenance procedures. Convenient check points make it easy to do routine maintenance, while a tilting cab simplifies service work.
The large-capacity radiator allows performance in severe and continuous operations. Access to the radiator and cooler is easy, making cleaning a simple process. Various parts of the engine can be accessed from the side, with the engine oil and fuel filter attached to the engine body extending out for easy maintenance.
The large-capacity two-stage forced air cleaner removes over 99% of airborne particles, reducing the risk of engine contamination and lengthening the intervals for cleaning and cartridge change. Integrated grease piping is designed for easy maintenance of the swing bearing and swing cylinder. The fuse box is conveniently located in a section of the storage compartment behind the operator's seat. Space is also provided for easy adjustment or replacement of the fan belt.
