Analysis of methods and designs of test benches for studying the process of rock cutting by different types of cutting tools of mining equipment

Frozen overburden rocks of the permafrost zone are prone to congealing upon their blasting, up to formation of a monolith, regardless of the time of year. In order to predict the decrease in the productivity level of mining equipment in such conditions, it is necessary to study the process of cutting the frozen rocks by different types of cutting tools of the mining machines. The article analyzes the existing laboratory benches and experimental devices, as well as methods of work execution that were published in research and technical literature dedicated to investigating the process of cutting hard and frozen rocks by different types of cutting tools of mining equipment. Most studies of the cutting process are carried out on homogeneous samples mainly to justify rational parameters of the cutting tools, for which the authors develop laboratory models, since it is practically impossible to cover the entire range of changes in the physical and mechanical characteristics of frozen soils in field conditions. It is noted that the existing laboratory benches and experimental devices make it possible to study the force and energy indices of the cutting processes as well as the parameters of elementary chipping depending on the depth of the cutter impact on samples and in natural conditions. At the same time, the review has shown that in the scientific and technical literature there is practically no information on laboratory or field studies of the cutting process of re-frozen blasted mass of permafrost rocks.