During operation, the hinge connections of mine supports practically stop rotating. This is due to the fact that, as a result of the aggressive mine water and strong dustiness, the diametrical clearance of 1-2 mm between the axis and the bushing is tightly filled with oxides and coal dust, especially in the connections of the base. This circumstance leads to the fact that the axes (pins) in the hinges lose their mobility and require significant effort for their dismantling. To repair the mechanized mine support, it is necessary to dismantle the hinge connections, which are formed by axes and holes in levers (traverses), base ears, and overlaps. Currently, the dismantling of hinge connections of mine supports is carried out using manual impact tools. This operation is extremely labor-intensive, physically heavy, and belongs to hazardous work. The goal of the study is to improve the working conditions of the operator during the dismantling process of axes in hinge connections of mine supports by using a mechanized specialized hydraulic press. To achieve the set goal, the following tasks must be solved: to determine the maximum permissible disassembly force of the axes, taking into account the strength of the load-bearing structure elements; to develop a concept of a mechanized hydraulic press, including the composition of the installation, the general technical description, the principle of operation, the kinematic scheme, and the tool. Studies have been carried out on the deformation modeling of mine support elements under load using the SOLIDWORKS Simulation calculation module to determine the maximum permissible disassembly force of the axes. It has been shown that the disassembly load of the shaft support axis with a force of more than 1000 kN leads to the loss of the structural strength reserve, which is unacceptable. An effective technology for dismantling the axes of a mechanized mine support has been proposed. A concept of an original specialized hydraulic press "Kit-100" for dismantling axes has been developed, which allows replacing the physically heavy and dangerous work of the operator with a lighter, mechanized process.

In modern mechanical engineering, a method of single-operation extraction of cylindrical parts from a metal grid with a square mesh is known, which, in particular, has found application for the manufacture of microphone casings. Further improvement of the technology of extracting parts from a metal mesh in the direction of increasing the relative height of the stamped part is associated with the use of a multi-operation method of extraction. The study of this process will allow to significantly reduce the limit coefficient of extraction and thereby significantly increase the relative height of the part. Therefore, the work aimed at improving the technology of manufacturing parts from a metal mesh due to the use of a multi-operation method of extraction is an urgent scientific and practical task. The purpose of the study is to improve the technology of manufacturing cylindrical parts from a metal mesh by using a multi-operation method of drawing. The result of the work is the study of physical limitations that determine the limiting coefficient of multi-operational extraction of cylindrical parts from a metal mesh. The phenomenon of elasticity of the mesh wires was revealed, as a result of which the side wall of the part acquires a curved, close to conical shape. The physical similarity between the process of deformation of a single wire of a metal mesh during multi-operation drawing and the process of bending a flat workpiece is shown, which allows determining the technological effort of each drawing operation using formulas for calculating the bending force. In addition, two forms of instability of the process of multi-operational drawing of cylindrical parts from a metal grid with a square mesh were revealed, and a new method of drawing was proposed, which creates such stamping conditions, in which asymmetric deformation of the part (irreparable defect) is not observed, and separate additional means for cutting the edge of the stamped parts are not used.

In modern mechanical engineering, electrical discharge machining (EDM) methods are widely used for machining bodies of rotation from difficult-to-machine materials. Those methods ensure sparing cutting and make it possible to machine any electrically conductive material irrespective of its physical and chemical properties, in particular hardness. There is a known method for dimensional machining of bodies of rotation with electric arc using a wire electrode tool that is pulled along in the machining area thus "compensating" for that tool's EDM wear and tear. The machining accuracy is therefore significantly heightened. However, when implementing this method, an effect of splashing the working fluid outside the working area of the machine and a pronounced luminous effect from the burning of the electric arc in the machining area are observed. That worsens the working conditions. In addition, when pulling the wire electrode tool along the convex surface of the electrode holder, the sliding friction arises, which eventually leads to mechanical destruction of the contact point. As a result, a deep kerf is formed on the electrode holder. When the depth of the kerf reaches the diameter of the wire electrode tool, the destruction of the electrode holder by the electric arc begins. Consequently, the durability of the electrode holder in the known method is unsatisfactory. A method of dimensional machining of bodies of rotation with electric arc using a wire electrode tool with the immersion of the machining area in the working fluid has been proposed, which makes it possible to improve the working conditions of the operator by eliminating the effect of fluid splashing and removing the luminous effect of arc burning in the machining area. In addition, it has been proposed to make the electrode holder in the form of a roller that rotates with a guide groove for the wire electrode tool, while the nozzle for creating the transverse hydrodynamic fluid flow has been proposed to be mounted in a separate fixed housing that is adjacent to the electrode holder. This technical solution replaces the sliding friction with the rolling one thus enhancing the durability of the electrode holder. Mathematical models of the process characteristics of the DMA-process (dimensional machining with electric arc) for bodies of rotation using a wire electrode tool with the immersion of the machining area in the working fluid have been obtained that make it possible to control the machining productivity, the specific machining productivity, the specific electric power consumption, and the roughness of the surface machined.

The basis of any knowledge is the knowledge of the essence of the object. In this, in fact, is the main task of science. The logic of the development of knowledge leads to the need to clearly distinguish what constitutes the essence of the object, from what it seems, as we see it. Essence is a nodal point of internal communication of the main moments, sides of the object, and comprehend the essence of the object, it is to understand the causes and conditions of its occurrence, its determining properties, the laws of his life, characteristic of his contradictions, trends of development. In this connection, it has been shown that dimensional electric arc machining has a natural connection and the same physical nature with known methods of electrodischarge processing, and the dissimilarity of the methods of electrodischarge processing, their removal, which are observed, are only different forms of detection of the same physical essence. The stages of the development of electrodischarge processing are described, which allows us to conclude that the dimensional machining of an electric arc has a natural connection with known methods of electrodischarge processing, based on the use of a non-stationary arc discharge, and its appearance is prepared by the previous development of electrodischarge processing, is the natural development of the latter, and, consequently, dimensional electric arc processing can be considered as a method of electrodischarge processing. It is clear that the size of the electric arc can not solve all the problems of electrodischarge processing, therefore, not only does it exclude, but also envisages the widespread use of known methods of electrodischarge processing-electroscope, electromotive pulse and electrocontact, each of which has its own characteristics, has its area of industrial application and is continuously improved, complementing each other. Therefore, it can be noted that with the advent of dimensional machining with an electric arc, the technological capabilities of electrodischarge processing in general have increased significantly, its economic efficiency and competitiveness has increased with other methods of metal working and, above all, with the processing of metals by cutting.. electric arc, electrospark processing, electroimpulse processing, electrocontact processing, electrodischarge processing, dimensional electric arc processing (