The article contains a description of the design solutions proposed by the authors for a hybrid wind turbine bearing, in which the sliding part takes over the load to the turbine shaft after reaching the shaft rotation speed, ensuring hydrodynamic lubrication of the plain bearing and relieving the rolling bearing. This allows for low starting resistance of the power plant and ensures quiet operation during use. Two conceptual solutions of a hybrid bearing were presented, differing in the shape of the plain bearing journal. A mechanism for automatic switching of the load between a rolling and a plain bearing was developed. A solid simulation model of this mechanism was built in the Autodesk Inventor—Dynamic Simulation software Inventor Professional 2023 environment, and its operation was simulated. The results confirmed the usefulness of using this design in shaft-bearing systems of wind turbines with a vertical axis of rotation. Based on the simulation, the speed at which the thrust roller bearing will be released was determined. Technical parameters of a plain bearing with a spherical journal shape were calculated. The height of the lubrication gap and the shaft rotational speed at which the bearing load capacity index reaches a critical value were determined.

The article discusses laboratory methods and the corresponding computational methods verifying compliance with the normative requirements regarding the lateral correction force of the powered roof support. The currently used flat model only allows for checking the normative requirement in relation to the sum of active forces of the correction cylinders installed in the roof support. Determining the required value of the active force of each cylinder is possible due to the simplified FEM model of a powered roof support, described in the research work, treated as a uniform weightless elastic body loaded with a concentrated force recreating the weight of the roof support located on an inclined longwall panel. The third analysed computational method involves determining the reaction in the four correction cylinders of the roof support, creating a spatial, statically indeterminate system of forces. It enables determining the range of variability of the response in the correction cylinders as a function of the distribution of floor pressure on the roof support base. The discussed computational methods were used to determine, for example, the lateral correction force of one of the types of powered supports used in a longwall panel inclined at an angle of 35°. The usefulness of the discussed calculation methods at various stages of the designing process of the powered support and its certification has been confirmed.

The problem of cooperation of powered roof support with the floor in the aspect of shaping its design is presented. From the analysis of the simplifying assumptions considered so far in the methods for determination of roof support’s base pressure on the floor, it results that they are not satisfied in the case of bases of the catamaran type, commonly used in currently manufactured roof supports. Model of cooperation of the base lying on the floor, prepared by the finite elements method is described and the results of computer simulation of the base action on the floor are given. Considering the results of numerical analyses, the factors influencing the pressure distribution of the base on the floor as well as its maximal value, have been identified.

Analysis of the rock mining process using an experimental cutterhead employing milling and chipping processes is the subject of this article. Based on a bibliographic review of the energy consumption of rock mining and wear and tear of various mining tools, a stand test programme for the rock mining process using the experimental cutterhead was developed. Based on the following measured parameters—hydraulic motor supply pressure and displacement, hydraulic motor shaft speed, cutterhead web depth, cutterhead tilt angle relative to the mining direction, feed pressure in the advance cylinder, duration of each mining stages, cutterhead travel distance, angle of the cutterhead chipping part, and known physical and strength parameters of the mined rock—the following parameters were determined: cutterhead advance speed, cutterhead advancing force, cutterhead driving motor power, advancing cylinder power, and the parameters of energy consumption in the mining process, including specific energy of mining, specific energy of feed, and specific energy of cutting. The effects of cutterhead advance speed and tilt angle on the specific mining energy and the grain size distribution of the mined rock were determined. Analysis of test results enabled the development of the procedure for selecting the most favourable parameters of rock mining technology when using an experimental cutterhead.