The key components of Surface mining technology

Cutting drum

The mechanically driven cutting drum works against the direction of travel. Extremely robust tools on the drum mine the material by cutting and crushing it. The tools are arranged on the drum in the shape of a helix. Ejectors on the cutting drum assist in transferring the small-sized material to the conveyor system.

Conveyor system

The primary conveyor picks up the material in the drum housing and transports it towards the rear of the machine, where it is then accepted by the slewing and height-adjustable discharge conveyor. The discharge conveyor either loads the material onto trucks or dumpers, or discharges it to the side of the machine. The discharge height can be adapted to the height of the transport vehicles.

Automatic levelling system

Mining the material in precisely the required thickness is crucial for the selective mining of rock layers. That is the job of the machine’s automatic levelling system: It maintains the specified cutting depth.

Two control loops – one for each machine side – continually match the actual cutting depth with the pre-selected target values. This is achieved by optical or mechanical sensors scanning a reference surface. Changes in the reference plane level are compensated by means of proportional control. The automatic system responds quickly and without overshooting.

Slope sensors can additionally be used for levelling when the cut surface needs to have a particular cross slope.