Electrification of rock drills : An initial study of an electromagnetic percussion concept

Abstract: The world is looking for greener solutions and so is the mining industry. This quest has led to the question whether it is possible to have a completely electric rock drill. This work carries out an initial exploration of completely electrified percussion. Furthermore, it compares the preliminary performance of an electrified rock drill against a hydraulic counterpart. A mathematical model for an electromagnetic linear motor was developed and simulated as a component in the simulation software Hopsan. This component was then incorporated into a electromagnetic rock drill model which uses components from Epiroc’s in-house developed library. The electromagnetic rock drill model was then optimised and used to obtain the performance characteristics such as impact energy and frequency which were compared against one of the hydraulic rock drill models, COP 1838. The results show that it is possible to reach the same performance as the COP 1838 with enough input current. The characteristics were then studied with respect to variation of physical parameters of the electromagnetic linear motor and input current. Finally some limitations and strengths of the electromagnetic rock drill concept are discussed and some conclusions are presented.