Actuated Disc Cutting

Establishing the fundamentals of cutter/rock interaction and rock failure mechanism

Undercutting disc technology combines the robustness and wear resistance of roller discs (mainly used on TBMs) with the efficacy of drag cutters (used on road-headers) in one single technology to cut very hard rocks. Breaking the rock under direct tension, undercutting discs consume less energy than conventional roller discs. This means that the overall power, required to mechanically excavate the rock is significantly reduced, allowing to manufacture small, agile, potent and energy efficient hard rock excavation machines specific for hard rock mining environment, the capabilities that are essential to overcome the limitations imposed by a mine’s great depth, confined spaces or hard and abrasive materials. Low energy consumption also means that the rock removal rate can be enhanced as the power of the machine is increased without having implications on life of the mechanical components. Application of mechanised and autonomous rock fragmentation in hard rock mining ultimately facilitates selective and continuous production process, ideal for many mining applications, while reducing the operational cost and improving the safety and the productivity.

This project investigates actuated undercutting discs as a suitable low-energy method for cutting hard rocks, and aims to lessen the specific energy by reducing the forces associated with the rock cutting process. For a machine with a known power, reducing the energy that is directly consumed for rock failure allows for more power to be available for enhancing the rate of rock removal.

This research takes into account the kinematics of the undercutting tools, the tool/rock interaction and the rock properties when studying the mechanics of the rock failure. Investigating the boundary condition at the cutter/rock interface and its effect on the consequential mode of failure, the project formulates the governing disc/rock interface laws. These laws allow controlling the mode of rock failure and the extent of the rock being removed to regulate and constrain the reaction forces within the limits of the machine power, while maintaining optimum performance.

Ultimately, the research outcome facilitates development of potent and energy efficient tools by preventing the energy loss in processes that are not required. This opens new avenues for the design and optimisation of the hard rock excavation technologies.

For more information about this project, please contact Dr Sevda Dehkhoda at sevda.dehkhoda@csiro.au.