ABSTRACT
The common mining method in hard rock mines is drilling and blasting. Blasting vibrations, the resultant surface or mine damages and the time for smoke clearing are some reasons to substitute a mechanical – breaking or cutting – mining system for heading by blasting. Therefore the application of an impact ripper is proposed because of the small tool wear and the possibility to utilize rock properties like jointing and layering. In compact hard rock the breaking efficiency will be significantly enhanced by the introduction of additional free faces to which the tool can break. To produce such free faces the practical and economical machines are diamond wire saws and circular saws. The paper describes the theoretical backround and first results obtained from underground tests in a base metal mine.
