Innovation: Wirtgen Surface Miners detect more and extract more

Wirtgen surface mining is an attractive option for many companies due to its high level of mining quality and efficiency, optimum exploitation of mineral deposits and environmentally friendly process. After all, where the conventional mining method requires different equipment for the individual steps involved – be it drilling, blasting, crushing or loading – with a surface miner, a single machine takes care of everything.

Selective mining is a key feature. Here, Wirtgen surface miners successively remove up to 83 cm of the surface material in layers. Because the cutting depth can be adjusted and regulated precisely, even thin seams of valuable mineral can be extracted precisely from along the dividing layer with the dead rock (intermediate rock veins, i.e. unworkable material).

With the new camera system, selective mining is now even more precise thanks to simple visualization of the rock interface. To this end, two cameras are mounted at the level of the cutting drum. In order to compensate for the slope of the layers, which are not always horizontal, one camera is attached on the left and the other on the right. These cameras transmit 1:1 photos of the surface to a double monitor in the cabin. The machine operator can accurately detect the transition from valuable mineral to interburden based on the different colors and/or structures of the two minerals and can then adjust the cutting depth, if required.

Thanks to this precision mining process, a greater quantity of material with a high degree of purity is loaded onto the trucks and transferred to the processing plants while the interburden remains in the mine. The result: fewer truck loads and above all greater efficiency in the processing plants. This significantly reduces downstream process costs.

At the end of processing, a much larger quantity of high-quality, sellable minerals remains than when the useful minerals are extracted by conventional means. For mining companies, this equates to an increase in profits.

The second innovation also maximizes profits. This is because Wirtgen's newly developed cutting drum unit for the Surface Miner 4200 SM has been specially designed for the windrowing method. Capable of outputs up to 15% higher than a standard cutting drum unit, it will also reduce tool consumption by up to 15%. These advancements are the result of an optimized milling drum design. The essential feature here is the increased tool spacing of 75 mm – this being the horizontal distance between the tool cutting tracks. This boosts the cutting performance so that more minerals can be deposited behind the Surface Miner in windrows.

Increased tool spacing also means that there are fewer cutters on the cutting drum – and that means fewer tool changes. The immediate effect: Downtime is also reduced. Overall, the surface miner can mine more minerals over a longer period of time than was possible to date working with a standard cutting drum in windrow mode.

Offering a wide variety of cutting drum configurations, Wirtgen can deliver the most productive cutting drum unit for each application and to match the composition of the material to be mined, both for windrowing and for direct loading via a conveyor belt.