Thomas Armstrong purchase latest Doosan wheel loaders
North West-based Aggregates operator takes delivery of two Doosan DL420 loading shovels
CUMBRIA-based Thomas Armstrong (Aggregates) Ltd have acquired two new Doosan DL420 wheel loaders from Carlisle-based Lloyd Ltd, the Doosan dealer fro Cumbria and southern part of Scotland. Operating at Thomas Armstrong quarries in Overby and Newcowper, the new machines represent the third generation of Doosan wheel loaders to be purchased by the company during the last 10 years.
The new Doosan DL420 wheel loaders have replaced the previous generation Doosan DL400 units which, in turn, succeeded two of Doosan’s Mega 400 generation wheel loaders formerly owned by Thomas Armstrong.
Frank Harkness, director of Thomas Armstrong, said: ‘The previous Doosan DL400 wheel loaders ran with no major issues for the last six years, as did the Mega models before them. The DL400s had each run up an impressive 14,500 hours and our drivers really liked them. When we came to replace them, we tested products from virtually every other major manufacturer, but the operators still expressed a strong preference for the new Doosan DL420 machines.’
With a bucket capacity of 4.0 cubic metres, the 22.3-tonne DL420 machine is powered by an 11-litre turbocharged, electronically controlled engine with a high-pressure unit injector unit and state-of-the-art combustion system. The engine develops 209kW (284hp) at 2,000 rev/min and offers a maximum torque of 148kg.m at 1,400 rev/min. Breakout force is among the highest in its category at 210kN.
The third-generation wheel loaders provide a static tipping load with 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 while dump reach is 1.4m. The turning radius at bucket edge is 6.995m at the maximum steering angle of 40 degrees.
Overby Quarry contains natural glacial sand deposit which is mined directly from the face by the Doosan DL420 wheel loader. The sand is loaded by the unit into a screening machine which separates different grades of gravel and sand. The screened sand is then stockpiled by the wheel loader for later use or loaded directly into trucks, mostly owned by Thomas Armstrong, for delivery to customers in the region.
The DL420 wheel loader at Newcowper Quarry works similar hours and works on a variety of applications. One of the main jobs for the loader is supplying a wash plant which grades materials into different sizes. The machine is also being used for remedial work around the quarry, as Newcowper is about to come to the end of its working life.
