Hybrid technological equipment: on the issue of a rational choice of objects of modernization when carrying out work related to retrofitting a standard machine tool system with an additional concentrated energy source

Abstract

Introduction. Improving the competitiveness of manufactured products is impossible without achieving high rates of resource and energy saving, while providing modern machine tools with the proper level of production flexibility in combination with guaranteed high values of processing productivity and the required level of parts manufacturing quality. Insufficient or excess capacity of technological equipment leads to a decrease in its economic efficiency, an increase in capital costs and, as a result, an increase in the cost of production. In the machine tool industry, which is a strategically significant and basic industry for the modernization of mechanical engineering, there is a special interest in the development of a new type of technological equipment that makes it possible to implement methods for modifying the surface layers of parts by processing it with concentrated energy sources. The combination of two processing technologies (mechanical and surface-thermal operations) in the conditions of integrated equipment makes it possible to level the shortcomings of monotechnologies and obtain new effects that are unattainable when using technologies separately. Ensuring an optimal level of quality — one of the unconditional requirements of a market economy — is a priority when developing the overall concept of technological equipment. Thus, it should be noted that the required and specific set of consumer properties are laid down during the design. And, therefore, the problem of quality optimization belongs to the field of forecasting and should be comprehensively addressed at the initial stage of developing the concept of technological equipment. The purpose of this research is to rationally choose the objects of modernization when carrying out work related to retrofitting a standard machine tool system with an additional concentrated energy source. Methods: Theoretical studies of the possible structural composition and layout of hybrid equipment during the integration of mechanical and surface-thermal processes were carried out taking into account the main provisions of structural synthesis and components of metal-cutting systems. During the research, issues related to the main provisions of system analysis, the geometric theory of surface formation, the design of metal-cutting equipment, methods of mathematical and computer modeling were raised. Results and discussion. Theoretical studies is found that currently, most of the parameter-oriented (dimension) series of general-purpose metal-cutting machines, built according to the law of geometric progression with a constant denominator, are the cause of multiple duplication of individual size ranges on machines of the same series. This gives grounds to talk about an unreasonable increase in the number of its members and, as a result, to an increase in the cost of designing, manufacturing and operating equipment. The authors adhere to the point of view that in order to ensure maximum efficiency of hybrid metal-cutting equipment, it is necessary to implement a parameter-oriented series built with a variable denominator. Such a principle of forming a parameter-oriented series makes it possible to provide an almost equal probability of processing a surface of any size with maximum productivity with a threefold overlap of ranges. Approbation of the technique for forming the structure of parametric series is carried out. It is theoretically proven that during the operation of vertical milling machines of the operating parameter-oriented series with the denominator φ = 1.26 (GOST 9726-89), there is a multiple overlap of individual size ranges, reaching a ninefold value in a certain range of sizes, which, of course, affects the efficiency of the existing machine tool holding. In turn, when synthesizing a promising parametric series of vertical milling machines with a cross table, it was shown that the new parameter-oriented series has a smaller number of members. Reducing the range of manufactured and modernized machine tools will increase the serial production and reduce current expenses on repairs and maintenance. Moreover, this effect is achieved while maintaining the flexibility of the machine tool holding.