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Item type:Наукова стаття, Influence of Technological Methods of Processing on Wear Resistance of Conjugated Cylindrical Surfaces(Springer, Cham, 2021) Zablotskyi, Valentyn; Tkachuk, Anatolii; Moroz, Serhii; Prystupa, Stanislav; Svirzhevskyi, KostiantynWear of any tribological pair leads to malfunction or failure of the entire mechanism. It is known that the process of wear of friction pairs occurs in three periods: running-in, normal wear, accelerated wear (destruction). Working surfaces of parts that are formed in the manufacturing process receive micro geometric characteristics (roughness, undulation), according to the regulated technological norms. These characteristics describe the properties of the technological surface topography. However, quantitative micro geometric parameters change as they evolve during running-in, and the surface receives a new operational relief that is stable for a long time during normal wear. It is an operational relief of conjugate surfaces that characterizes the qualitative properties of parts for a long period of operation. The running-in process, which is based on complex mechanical, physical, and chemical processes, determines the overall wear resistance of parts. After this period, the physical, mechanical, and geometric characteristics of the surface acquire optimal values corresponding to the operating conditions. Rational performance characteristics during normal wear can self-sustain, and they are continuously reproduced independently in the same values. This state of the surface layer is observed before the beginning of the third stage of the life cycle. Traditionally, to ensure regulated micro geometric characteristics of the working surfaces used grinding, smoothing, and lapping diamond pastes. At the present stage of development of equipment and technology in a row with the mentioned finishing operations, there is an operation of high-speed turning, which allows reaching high purity of surfaces with the lowest cost of the technological process.Item type:Наукова стаття, Methods of Evaluating the Wear Resistance of the Contact Surfaces of Rolling Bearings(2021) Svirzhevskyi, Kostiantyn; Zabolotnyi, Oleg; Tkachuk, Anatolii; Zablotskyi, Valentyn; Cagáňová, DagmarIn modern conditions of development of mechanical engineering, high priority is given to experimental and material science aspects of assessing the wear resistance of conjugate friction surfaces, which consist of the selection of materials with high wear resistance characteristics. However, this way, you can only reduce the intensity of the wear process, but not control the wear process itself and, most importantly, the changes in the state and performance of the mating surfaces that occur as a result of the wear process. The durability of machines is laid down at the design stage and depends on the design scheme, materials used, lubricants, and other factors. An increase in the durability of mated machine parts is impossible without creating modern engineering methods for calculating wear resistance, which would consider the physical and mechanical characteristics of materials (friction pairs, modes of operation of the load node, and angular velocity), external friction conditions (environment, and lubrication), as well as the design and technological features of the friction interface. During the wear of two contiguous bodies, the unevenness of one surface is exposed to the unevenness of the other surface. In this case, the irregularities of the more durable material act similarly to the abrasive elements, cutting off the thin chip from the micro-irregularities of the surface of the less durable material. At the same time, the irregularities that cut this chip wear themselves out, just as cutting abrasive tools wear out.Item type:Наукова стаття, The Structure of Automated Control Systems for Precision Machining of Parts Bearing(2022) Trokhymchuk, Ivanna; Svirzhevskyi, Kostiantyn; Tkachuk, Anatolii; Zabolotnyi, Oleg; Zablotskyi, ValentynOne of the ways to improve the quality of bearing parts is the introduction of automatic control systems to improve the technological reliability of machines and increase the accuracy of machining of roller bearing rings. A significant advantage of these systems is that it is possible to compensate for technological factors by cheaper means compared to such as increasing the rigidity of the technological system, processing in modeswith lower productivity, processing using more passes, usingmanualmethods to compensate for wear of cutting tools, maintaining the required rigidity of the machine and the accuracy of its elements through periodic repairs. These methods are associated with either a loss of cyclical productivity or a significant loss of unproductive nature. Therefore, the errors of automated control systems should be considered as processing errors or as a scattering field of the dimensions of parts manufactured on a machine equipped with an automatic control system for precision machining. The share of error of the most automated control system in the total balance of the total size error is quite small and does not exceed 10…20%. The task of improving the accuracy and ensuring stability in technological systems is complex, so it is solved only by a comprehensive method by improving the accuracy of all elements of the technological system. Thus, automated control systems for precision machining of bearing parts is one of the main subsystems of flexible automated production in the concept of Industry 4.0.Item type:Наукова стаття, Application of Carbide Cutting Inserts as Indenters for Surface Plastic Deformation(2023-03-15) Svirzhevskyi, Kostiantyn; Zabolotnyi, Oleg; Machado, José; Tkachuk, Anatolii; Boiarska, InnaSurface plastic deformation has a high productivity and allows for products with unique operational properties, namely: a high quality of the surface layer, increased support stability of the profile of the treated surface, a strengthened surface layer, and the formation of residual compressive stresses in the surface layer. The essence of smoothing is that a tool with regulated geometric characteristics of the deforming element (indenter) under specific technological processing modes penetrates the surface layer of the workpiece and slides, deforming the microgeometry formed as a result of previous technological operations. The article considers the option of using carbide-cutting plates as deforming elements. For this, a morphological table of methods of spatial orientation of the indenter-plate has been developed, which includes 27 possible options for its installation. The algorithm for calculating the geometry of the contact zone of the indenter and the workpiece is presented. The contact interaction of the indenter plate and the workpiece was studied. On the basis of morphological analysis and conducted applied studies, rational installation angles of the deforming element were determined. The interdependence of the properties of the surface layer on the technological modes of processing was defined.