First publishedin World Highways
The Doosan DX530LC-5 has a customised 18m boom for working in water and 900mm-wide tracks to keep the unit's ground pressure low
German contractor Kieswerke Silzen Peissen has purchased three new Doosan machines for the company’s Silzen-based operations for gravel extraction above and below water.
The new machines comprise the Doosan DL420-5 wheeled loader, a custom-made long-reach 60 tonne DX530LC-5 excavator and the state-of-the-art wheeledloader DL420CVT-5, with CVT, denoting a continuously variable transmission.
Silzen Peissen’s two plants in Silzen comprise about 70ha of approved mining area, of which around 20ha - called Plant 1 - is being developed underwater. Material obtained from the water in Plant 1 is cleaned in the company's washing systems, making it ready for sorting.
Plant 1 produces mainly concrete aggregates, screes and special building materials for golf courses and riding arenas as well as special sands for playgrounds.
The second one, Plant 2, in Silzen has been operating for about 15 years and is directly opposite Plant 1. Plant 2 produces materials for the road building sector. The permit for this work covers around 40 hectares.
The two wheeled loaders are used in above-ground mining and for loading operations while the DX530LC-5 excavator is responsible for extraction and earthworks underwater at Plant 1.
Underwater work was previously carried out using a nearly 40-year-old scraper that had to be replaced at short notice. The new excavator had to meet strict requirements, such as working in water up to 9m deep. It also had to be delivered within two months.
Dealer Atlas Hamburg offered a solution: a Doosan DX530LC-5 with a customised 18m boom. Other modifications include 900mm-wide tracks to keep the ground pressure as low as possible. Stability with the long boom was increased by widening the undercarriage and by adding a three-tonne counterweight. For machine control, Atlas Hamburg installed a 2D control system from Zimmermann. This helps the operator work efficiently and accurately, even without being able to see the attachments at the end of the boom.
In addition, the Doosan DX530LC-5 excavator uses a submerged quick coupler, a 1.7m³ Hardox dumping bucket for underwater construction and a 2,800mm pivoting trough for earthworks above water.
It all added up to value for money, said Norma Henkensiefken, owner of Kieswerke Silzen Peissen.
The latest addition to the fleet at KSP is the Doosan DL420CVT-5 wheeled loader, the first model in the Doosan wheeled loader range to be equipped with a continuously variable transmission. A CVT transmission is composed of a hydraulic motor combined with a hydraulic pump which provides a smooth and continuous speed variation.
"Compared to the DL420-5 with conventional gearboxes and also compared to other comparable machines in our fleet, the DL420CVT-5 delivers significantly more power with lower fuel consumption," said Jens Rausch, operations manager at KSP.