Models describing the process of mining of dense rock with a symmetrical dise tool and a high pressure water jet are described in the article. Results obtained in earlier research work on the process of rock mining using a high pressure water jet and a symmetrical disc tool are compared with results of the models.

Assumptions for the process of hydromechanical mining of rock using a single symmetrical disc tool along a circle route were made based on the obtained conclusions. It has been shown that due to significant discrepancies between the real results and results obtained from the analysed models, these models must be adjusted or new ones developed.

On the basis of the results obtained from the conducted research empirical as well as analytical and empirical models were developed, describing the process of rock mining using a high pressure water jet and hydromechanical mining of rocks using a symmetrical disc tool along a circle route. The research was conducted at a special research station for research on single mining tools. Work conditions there were close to real conditions of the mine wall, simulated for a diameter close to 1 200 mm.

The processes of rock mining both using a high pressure water jet and using a symmetrical disc tool with or without the assistance of high pressure water jets were examined separately. A computer program was created on the basis of the developed models, thereby enabling calculation of the load of the symmetrical disc tool mining along a circular route and the mining effect during mining for pre-set parameters.

Diagrams for selected parameters, obtained with the aid of the computer program and illustrating the most favourable parameters for the operation of the system, are presented as follows: symmetrical disc tool - high pressure water jets with the least weight on the tool, the lowest unit mining energy or the greatest quantity of mined output, and comparison of results when mining mechanically and hydromechanically.

The results obtained for the examined research area show the effect high pressure water jet assistane on the load of the symmetrical disc tool mining along a circular route and on the effect and energy consumption of the mining process