Authors:Vitalii Lysenkov, Dmitriy Demin Pages: 6 - 11 Abstract: The object of research in the paper is the process of bottom pressing in the manufacture of disposable sand molds. The existing problem is that in practical conditions it is almost impossible to determine the forces acting in the molding mixture in the process of lower pressing. This leads to the fact that in the real process, with the selected pressing modes, the requirements regarding the density of the mixture in the furnace during the manufacture of the half-form may not be met. To solve this problem, it is proposed to build a method that does not require measurement of effort in the system, but allows to obtain dynamic characteristics of the pressing process based on an adaptive approach to determining the technological effort. It is hypothesized that it is possible to evaluate the dynamic characteristics of the compaction process in an industrial process without measuring the forces acting in the system during lower pressing. This can be done regardless of which drive is used - pneumatic or hydraulic. It is demonstrated how the kinematic characteristics of the process can be determined based on the use of D-optimal plans on a segment. The proposed method includes 12 points that involve the implementation of experimental and industrial studies directly on the operating equipment based on the use of D-optimal plans and further adaptation of the process of finding the force acting on the molding mixture. The adaptation is based on a preliminary assessment of the kinematic characteristics of the pressing process and involves the calculation of the technological effort that ensures the achievement of the given time of the coordinate of the lower plane of the molding mixture obtained from the equation of kinetics. The results of the implementation of the method make it possible to identify different stages of the pressing process and the distribution of the density of the mixture along the height of the column of the molding mixture. The practical implementation of the method can help in setting up the control system of the lower pressing process depending on the equipment parameters. Therefore, the presented research will be useful for machine-building enterprises that have foundries in their structure, where shaped castings are made in one-time sand molds. PubDate: 2023-09-26 DOI: 10.15587/2706-5448.2023.288152 Issue No:Vol. 5, No. 1(73) (2023)
Authors:Mykola Zenkin, Andrii Ivanko, Vasyl Kokhanovskyi Pages: 12 - 19 Abstract: The object of research is computerized polygraphic systems, their technologies, current development trends and prospects for application in modern polygraphic production. The study solves the problem of determining current trends in the field of computerized printing systems, as well as developing forecasts for their future, taking into account modern technological innovations and the possibility of their application in printing. It was determined that the modern world is experiencing rapid technological changes. The integration of computer technologies in various branches of production not only optimizes processes, but also opens up new opportunities for development and innovation. The results were obtained: it was found that computerized polygraphic systems are becoming more and more widespread, providing the opportunity to improve product quality, reduce production costs and increase productivity. It has been proven that modern printing technologies demonstrate an impressive dynamic of progress, taking place in the context of intensive development of information and communication industries. The printing industry adapts quickly, assimilating modern technological advances and immediately implementing them into the production process. It has been confirmed that computer printing systems are actively developing, responding to the increase in market requirements and contributing to the improvement of print quality. Today's technologies, including 3D and 4D printing, digital stencil technology, laser engraving and central print management system (CPMS), are already integrated into the printing industry, providing automation, precision and efficiency. The obtained research results make it possible to ensure the industrial production of more individual, multifunctional and flexible products, expanding the horizons for printing companies. Forecasting the development of technologies and their application in printing production allows companies to always be one step ahead of competitors, rationally invest in innovation and effectively respond to changing market conditions. Given the globalization of the market and the growing demands for the quality of printing products, the ability to anticipate future trends and adapt to them is becoming a key success factor for manufacturers. PubDate: 2023-10-31 DOI: 10.15587/2706-5448.2023.290273 Issue No:Vol. 5, No. 1(73) (2023)
Authors:Pavlo Anikin Pages: 20 - 27 Abstract: The object of the research is the possibilities of using a wireless communication system for feedback to improve the additive manufacturing process of a part using the arc welding technology with temperature control for heat propagation. The problem to be addressed includes determining the geometric properties, print topology, and temperature control regimes for the mentioned part. It also involves the installation of telecommunications sensors and cameras for temperature monitoring, conducting simulation calculations using ABAQUS software, and physical experiments. The results of the work include simulating the additive manufacturing process at necessary hierarchical system levels, considering specific requirements and obtaining the required geometric dimensions. Residual stresses have been analyzed, software-related heat propagation issues have been discussed, the influence of cooling on production quality has been verified, and optimal print parameters have been created. Additionally, the potential use of a feedback telecommunication system with telecommunication devices such as cameras and laser sensors for temperature control has been explored. The obtained data has been used for the possibility of generating an automated program for robot control during the additive manufacturing process. Based on the data obtained, residual stress values and defects in the produced samples were determined. A real experiment was conducted, and the results of the real experiment were compared and analyzed. The assessment of the impact of the feedback telecommunication system on the additive manufacturing process using arc welding with heat propagation control through cooling periods in practice allows for improved printing quality, technology of the produced part, cost reduction, and speeding up the production process. PubDate: 2023-10-31 DOI: 10.15587/2706-5448.2023.290204 Issue No:Vol. 5, No. 1(73) (2023)
Authors:Stefan Zaichenko, Denys Derevianko, Roman Kulish Pages: 28 - 31 Abstract: The work considers the problem of determining the factors of energy efficiency of industrial parks in the conditions of military aggression in the conditions of the introduction of the National Economic Strategy and regulatory influence on Industrial Parks in Ukraine. The energy efficiency of industrial parks primarily depends on the main parameters of the selected technological processes that are embedded in the basis of enterprises and their productivity. A significant factor affecting the environmental friendliness and energy efficiency of industrial parks is the method of energy generation. On the basis of the analysis of the work of enterprises operating in conditions of military aggression, the main factors determining the energy efficiency of electricity production have been determined. Such factors are the overall efficiency of the power generating unit, which is determined by monitoring and diagnosing the power unit. Analyzing changes in energy efficiency, the characteristics of the power part of one of the most powerful diesel engines were selected. It is obvious that the diesel locomotive will consume more fuel to generate energy with a decrease in efficiency. The main diagnostic factors of generating equipment that affect the energy efficiency of industrial parks in conditions of military aggression are: the ratio of currents in compressor and depressurized modes, the real degree of compression, and as a result, the efficiency of the power plant. On the basis of the determined factors, the effectiveness of the implementation of the system of monitoring and diagnosing the power units of energy-generating equipment of enterprises in the conditions of military aggression was determined. Recommendations have been established to minimize fuel consumption and reduce emissions to ensure the main principles of industrial parks, environmental friendliness and energy efficiency. PubDate: 2023-10-28 DOI: 10.15587/2706-5448.2023.289928 Issue No:Vol. 5, No. 1(73) (2023)
Authors:Viktor Svitlytskyi, Sergii Iagodovskyi, Nataliia Bilenko Pages: 32 - 36 Abstract: The object of research is the drill string bottom structure using the correcting devices of drilling modes to control the dynamics of the drill string. The work is aimed at the study of longitudinal, torsional and transverse oscillations when adjusting the axial load on the bit by using a drilling shock absorber with a two-link characteristic. A dynamic model of the drill string during the drilling process is presented, which is a concentrated-continuous nonlinear system that interacts with the ball bit and the downhole engine as a source of energy. It is shown that elastic oscillations of all types affect the interaction of the bit with the outcrop rock. In order to evaluate drilling performance, it is necessary to take into account not only longitudinal, torsional and transverse oscillations, but also parametric oscillations, which are associated with the deformation of the weighted drill pipe under axial loads and during its rotation in the process of deepening the hole. It was found that transverse vibrations of weighted drill pipes, as a flexible element, during the drilling process are, as a rule, parametric in nature. They lead to the appearance of additional stresses in the elements of the column and, as a result, to the acceleration of their destruction and accelerated wear of the bit arms and rolling bearings. It is proved that in the future, for the development of dynamic models, it is necessary to take into account their hydrodynamics and the type, design and parameters of the applied punching elements. The obtained research results can be applied in practice in the process of designing the structure of the drill string bottom structure (DSBS) using correcting devices of drilling modes to control the dynamics of the drill string, by using a drilling shock absorber with a two-link characteristic in order to correct the axial load on the bit. PubDate: 2023-10-31 DOI: 10.15587/2706-5448.2023.290145 Issue No:Vol. 5, No. 1(73) (2023)
Authors:Sergii Sagin, Arsenii Sagin Pages: 37 - 43 Abstract: The operation process of marine diesel engines when using fuel with a sulfur content of no more than 0.1 % was chosen as the object of the study. Similar types of fuel are characterized by a lower auto-ignition temperature and higher calorific value. During combustion, this leads to an increase in the rate of fuel combustion and the degree of pressure increase during combustion, precisely because of this, the dynamic loads on the parts of the cylinder-piston group and diesel engine bearings increase. Also, this (due to the increase in temperature at the end of combustion) creates conditions for an increase in the concentration of nitrogen oxides in diesel exhaust gases. This (namely, the change in dynamic and thermal loads that occur during the use of fuels with a reduced sulfur content in marine diesel engines) leads to the occurrence of emergency situations. As a method of managing the risk of such emergency situations, the reconfiguration of the high-pressure fuel equipment, namely the change of the advance angles of the fuel supply, is proposed. The research was carried out on a vessel intended for the transportation of containers and on which a marine diesel engine 8K80ME-8.2-TII MAN-Diesel & Turbo was installed as the main engine. Combustion pressure, the degree of pressure increase during combustion, the temperature of exhaust gases, and the concentration of nitrogen oxides in exhaust gases were chosen as the indicators for evaluating the use and implementation of the proposed method. It has been experimentally proven that this results in an increase in the environmental sustainability of diesel operation by 3.61–10.97 %, an increase in thermal stability – up to 2.54 %, and an increase in dynamic stability – up to 4.82 %. This is due to the shift of the self-ignition and combustion process towards expansion and the corresponding decrease in pressure and temperature at the end of combustion. The most favorable use of this method is on modern diesel engines that have an electronic fuel injection control system, so they do not require mechanical reconfiguration of fuel pumps. Taking this into account, the method based on the change of fuel advance angles is defined as the one that provides management of the risk factors of emergency situations when using low-sulfur fuel in marine diesel engines. PubDate: 2023-10-31 DOI: 10.15587/2706-5448.2023.290198 Issue No:Vol. 5, No. 1(73) (2023)
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