Determination of optimal coordinates for switching processing cycles on metal-cutting machines

OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 1 Determination of optimal coordinates for switching processing cycles on metal-cutting machines Vilor Zakovorotny a , Valery Gvindjiliya b, * Don State Technical University, 1 Gagarin square, Rostov-on-Don, 344000, Russian Federation a https://orcid.org/0000-0003-2187-9897, vzakovorotny@dstu.edu.ru , b https://orcid.org/0000-0003-1066-4604, sinedden@yandex.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2021 vol. 23 no. 1 pp. 56–67 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2021-23.1-56-67 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov ARTICLE INFO Article history : Received: 08 November 2020 Revised: 05 December 2020 Accepted: 06 January 2021 Available online: 15 March 2021 Keywords : Minimization of the above cost of manufacture Quality of parts manufacturing The coordinates of the switching cycles Funding The reported study was funded by RFBR according to the research proj- ects: “Development of the theory of analysis and synthesis of controlled self-organization in a dynamic cut- ting system during processing on the example of manufacturing parts on lathes”, No. 19-08-00022; “Devel- opment of methods for analysis and synthesis of a dynamic cutting system based on the criterion of minimizing the reduced manufacturing costs”, No. 20-38-90074. ABSTRACT Introduction. One of the ways to improve the ef fi ciency of processing on machines is to coordinate the CNC program with the changing properties of the dynamic cutting system. If this takes into account the tool wear and the associated with it changes in the parameters of the dynamic cutting system, then the cutting speed to ensure the minimum wear rate is reduced along the cutting path. The corresponding feed rate is reduced even faster, since it is necessary to ensure a constant deformation displacement of the tool relative to the workpiece. The evolution of the properties of the cutting process (for matching with which the trajectories of the operating elements of the machine are corrected) depends on the power of irreversible transformations of the energy supplied to cutting. This reduces the processing ef fi ciency. Therefore, a new for the considered subject area problem of determining the coordinates of the tool movement relative to the workpiece is formulated, starting from which further processing is economically inexpedient. In this case, it is necessary, after processing the next part, to ensure the replacement of the tool and carry out its changeover. Subject. A metal-cutting machine of a turning group, the trajectories of the executive elements of which are controlled, for example, by a CNC system. The purpose of the work. Mathematical simulation and methods for determining the coordinates at which it is necessary to replace the tool. Method and methodology . The necessary conditions for the optimality of determining these coordinates are proved. Mathematical tools are provided that allow calculating the coordinates at which the given manufacturing costs take the minimum value according to the given trajectories. The probabilistic characteristics of evolutionary trajectories are taken into account. Results and discussions. The analysis of the ef fi ciency of using the technique in industry depending on the cost of the machine and tool together with its replacement and readjustment is given. The proven optimality conditions and the given mathematical tools complement the knowledge about the optimization of controlled machining processes on machines. Conclusions. The results of the study show new options for the organization of tool replacement, aimed at improving the ef fi ciency of processing by software methods using a CNC system. For citation: Zakovorotny V.L., Gvindjiliya V.E. Determination of optimal coordinates for switching processing cycles on metal-cutting machines. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2021, vol. 23, no. 1, pp. 56– 67. DOI: 10.17212/1994-6309-2021-23.1-56-67. (In Russian). ______ * Corresponding author Gvindjiliya Valery E. , Post-graduate Student Don State Technical University, 1 Gagarin square, 344000, Rostov-on-Don, Russian Federation Tel.: +7-918-583-23-33, e-mail: sinedden@yandex.ru Introduction After the publication of works [1, 2], many problems of various systems dynamics interacting with different environments began to be considered with the view of their evolutionary changes and self- organization [3–7]. The paper [3] showed that synergetic coordination of external control with the