The design of an instrument for measuring the cutting characteristics of rocks in situ

One of the most important aspects in the selection of suitable machines for coal and rock cutting is the determination of the cutting characteristics of the material. This paper describes the research carried out into the design of a system for testing rocks under conditions which resemble, as closely as possible, those under which mining machines operate. The equipment was required to be portable and capable of being used under a wide variety of conditions; being hydraulically powered, the system could be used on the coal face or in conjunction with tunnelling machines. Initial surface trials highlighted a number of problems which were subsequently eliminated by improved design of the system. Subsequent underground trials proved that the equipment was reliable and capable of measuring quantitatively the magnitude and variation in cutting forces in different materials.