The Shaft Boring Cutterhead (SBC) was developed for mechanized full-bottom shaft sinking in hard rock to a depth of 1,000 meters. The cutterhead is conical in shape and equipped with disc cutters. The excavation sequence is highly automated.
The excavation chamber is filled during the advance and can thus also be used as a shaft sump for water ingress from the geology. The conical cutterhead has a speed of 2 to 3.5 revolutions per minute and thus achieves an advance rate of about 1 centimeter per minute depending on the geology.
By means of liquid mucking, a pump system transports the drill cuttings from the excavation chamber through the machine to a separation plant. Here fine and coarse material is separated from the suspension. Coarse material is transferred to the shaft conveyor by buckets, while fine material is pumped to the surface with a separate slurry circuit, which is also available for shaft drainage.
After an advance of 1 meter has been sunk, the SBC attached to the shaft ropes is lowered.
The possibility of installing shaft lining from a work deck of the SBC is adapted to the requirements of the project.
Proven technology as the basis for new developments
The components used in the SBC have proven themselves worldwide in Herrenknecht shaft sinking and tunnel boring machines.
Although on the SBC work steps are carried out in parallel, the machine concept has significantly increased work safety compared to conventional shaft sinking. During excavation, the personnel are not exposed to the unlined shaft wall. Also, contact with silicate or other dust is reduced to a minimum.
With the further development of existing technologies and profound engineering know-how, Herrenknecht opens up new business areas. In the field of mining in particular, innovative machine concepts are needed to safely and efficiently develop deposits even at great depths.