2023 № 98 Різання та інструменти в технологічних системах

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https://repository.kpi.kharkov.ua/handle/KhPI-Press/65691

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Increasing the accuracy of defectoscopy by the method of active thermography of products made of non-metallic heterogeneous materials and used in engineering
(Національний технічний університет "Харківський політехнічний інститут", 2023) Tonkonogyi, Vladimir; Stanovskyi, Oleksandr; Holofieieva, Maryna; Levynskyi, Oleksandr; Klimov, Serhiy
Nowadays, non-metallic heterogeneous materials are widely used in mechanical engineering, which is primarily due to their unique properties, such as strength, light weight, corrosion resistance, and high vibration, sound, and heat insulation characteristics. At the same time, non-destructive control methods that would allow to obtain the most complete picture of the defective state of products made of such materials are of great importance. The main task of the work is the development of optimal algorithms for determining each defect of a product made of non-metallic heterogeneous material with the establishment of its exact location, including the depth of occurrence, as well as its geometric parameters. The method of thermal non-destructive testing is considered promising. Studies of the accuracy of determining the parameters of defects in non-metallic heterogeneous materials by the specified method have been carried out.
Roundness error and topography of hard turned surfaces
(Національний технічний університет "Харківський політехнічний інститут", 2023) Sultana, Jakiya; Sztankovics, István
Accuracy and topography are significant indicators of precision machined high-quality surfaces. Case hardened steel (16MnCr5) was analyzed to obtain information about the effects of technological data and the connections between the analyzed accuracy (roundness) and roughness parameters (Sa, Sz, Ssk, Sku). It was found that the feed rate has a significant influence on the roundness and the roughness parameters, and there are strong relationships between the roundness and these roughness parameter values: the correlation coefficients varied between 0.78 and 0.85.
Analysis of selected function-defining 2D surface roughness parameters in tangential turning
(Національний технічний університет "Харківський політехнічний інститут", 2023) Sztankovics, István
Among other, more frequently analysed surface topography parameters, the function-defining parameters must be analysed in different machining procedures to outline their application possibilities. These values are the core roughness, the reduced peak height, the reduced valley depth, the skewness, and the kurtosis of the roughness profiles. Tangential turning is a promising machining procedure, which can produce ground-like surfaces with twist-free properties by defined cutting edged tools. The achievable productivity is also very high. Therefore, in this paper, these roughness parameters were analysed from 2D roughness profiles measured on surfaces machined by tangential turning.
Improving the efficiency of maintenance process in manufacturing systems using industry 4.0 tools
(Національний технічний університет "Харківський політехнічний інститут", 2023) Hermans, Marc; Tamás, Péter
In ever bigger quest to maximal efficiency, this article wants to show a route for Total Production Maintenance (TPM) at maximal efficiency. By bringing the digital twin into the real world, this essay wants to show how a digital twin can be used as a reliable basis for controlling the running line. But before the digital twin can be used at its maximal potential, a common ground must be defined not only in calculating Overall Equipment Effectiveness (OEE), but also in categorizing TPM tasks according to 3 factors of OEE. The paper outlines the foundations of a new concept that has not been applied in practice
Experimental investigation of tribology-related surface topography parameters and hardness of 16MnCr5 case hardened steel
(Національний технічний університет "Харківський політехнічний інститут", 2023) Nagy, Nora
Tribological properties are determinant in the functionality of contacting surfaces of machine elements. The wear resistance or load bearing capacity influence the lifetime of these parts. In this study tribology-related surface topography parameters (Ssk, Sbi) and the hardness of hard turned surfaces are analyzed after hardness and topography measurements. Correlation coefficients were calculated for their relationships. It was found that the cutting parameters affect the wear resistance and the hardness in the opposite direction.
Optimisation of interrupted grinding parameters according to the temperature criterion
(Національний технічний університет "Харківський політехнічний інститут", 2023) Novikov, Fеdir
In the paper analytical optimization of discontinuous grinding parameters according to temperature criterion is carried out and on its basis conditions for significant reduction of cutting temperature, which consist mainly in increasing the number of contacts of working ledges of discontinuous wheel with fixed cross-section of machined workpiece, are determined. It is established by calculations that providing 20 contacts the cutting temperature may be reduced up to 3 times in comparison with the conventional grinding by a continuous wheel. This is achieved in the conditions of deep interrupted grinding with relatively low workpiece speed, as in the conditions of traditionally used multipass interrupted grinding not more than 6 contacts of working ledges of an interrupted wheel with the fixed cross-section of the workpiece are realized and the cutting temperature is reduced only in the range of 50 %. It is established by calculations that the minimum of cutting temperature at discontinuous grinding is achieved under conditions of equality of lengths of the working shoulder and the notch on the discontinuous grinding wheel and their reduction. It is also established that excess of the length of the working ledge over the length of the notch of the discontinuous wheel leads to insignificant increase of the cutting temperature. This reduces the wear of the discontinuous wheel and increases the machining capacity without actually increasing the cutting temperature. The paper shows that the obtained theoretical solutions are a necessary condition for ensuring a significant reduction of cutting temperature in discontinuous grinding. A sufficient condition should be considered as complete or partial cooling of grinding zone between contacts of machined workpiece with working jaws of discontinuous grinding wheel by intensive supply of effective technological media into the grinding zone.
Investigation of face milled surface topography on C45 workpiece assuming movement at 30° and 60° to feed direction
(Національний технічний університет "Харківський політехнічний інститут", 2023) Nagy, Antal; Kundrak, Janos
When surfaces with anisotropic texture are moved in different directions related to their assembled counterpart during operation, the friction conditions change, as they are determined by the lay of the topographies. In the article, contributing to the exploration of this characteristic, we analyze the inhomogeneity of the topography on a face milled plane surface with a symmetrical setting in sections at an angle of 30° or 60° to the feed direction. Roughness profiles are recorded at 13 pointslocated equidistantly from each other in each measurement plane, and the degree and distribution of the roughness deviations are determined on the surface.
Analyzing surface integrity elements of hard turned 16MnCr5 steel
(Національний технічний університет "Харківський політехнічний інститут", 2023) Molnar, Viktor
Surface integrity plays a determinant role in the functional requirement of precision machined parts. In the automotive industry billions of components are manufactured by using case hardened steels. In this study some surface integrity elements, such as surface roughness or residual stress are analyzed based on systematic machining experimental plan to optimize the applied cutting parameters. Recommendations are made for these parameters based on the measurement data and some widely used functional requirements.
Regularities of vibration finishing and grinding processing and directions of improvement of its intensity and quality
(Національний технічний університет "Харківський політехнічний інститут", 2023) Mitsyk, Andrii; Fedorovich, Vladimir
The data on the labor intensity of manufacturing engineering products and the share of finishing and grinding operations in the total labor costs of their manufacture are presented. The list and the degree of mastering the technological operations of finishing and grinding processing, performed in the conditions of machine-building industries during the last years are given. The grounds are given for highlighting the method of vibration processing as the most promising for ensuring complete mechanization of the process of finishing and cleaning, as well as achieving high technological characteristics of the surface roughness of parts. An assessment was made of the influence of modes, the trajectory of the movement of the reservoir and the grain size of the granules of the abrasive medium on metal removal. It is indicated that the intensity and quality of vibration treatment is estimated quantitatively by the weight removal of metal and qualitatively by the roughness of the processed surface. It is indicated that the determining factor in this case is the speed of the oscillating movement of granules and parts, the difference of which represents the speed of vibration processing, depending on the speed of the oscillating movement of the medium. It is noted that in order to increase the productivity of the process, it is necessary to increase the speed of the medium by increasing the frequency and amplitude of the reservoir oscillations. The layer-by-layer transmission of a force impulse from the bottom of the reservoir to the bulk medium is considered. The physical meaning of increasing productivity by increasing the amplitude of the reservoir oscillations is indicated. The conditions for obtaining metal removal are indicated, which provide increased efforts for the interaction of granules with parts at high micro-cutting speeds. Experimental studies are described to determine the influence of the amplitude and frequency of oscillations on the results of vibration finishing and grinding. Graphic dependences of metal removal were obtained for various ratios of the sample weight to the weight of the medium granule. The dependence of metal removal on the ellipticity coefficient and the amplitude of the reservoir oscillations was obtained in a similar way. It is noted that the vertical component of the amplitude during in-plane oscillations of the reservoir is the determining factor of the complex influence of the parameters of the ellipse coefficient of the trajectory of the reservoir and its amplitude of oscillations. It has been established that when using a coarse-grained abrasive, the penetration of grains into the metal of the part occurs to a greater depth and larger metal chips are removed with a large metal removal. With a small grain size of the abrasive, small chips are removed with a small metal removal and a decrease in the height of micro-roughness.
Optimisation of operator-machine assignment problem using excel solver
(Національний технічний університет "Харківський політехнічний інститут", 2023) Bányai, Tamá; Meczkó, Viktória
Although the fourth industrial revolution has greatly accelerated the automation of production processes, the importance of human resources has not diminished, as evidenced by the fact that multinational companies are increasingly investing more and more effort in determining the optimal allocation of machines and operators. In this paper, the authors present an approach to the operator-machine assignment task through a suitable model. The mathematical model presented issuitable to support the design of an appropriate human resource management strategy and the implementation of operative human resource management tasks in production systems of different sizes.
Modern developments related to the directed impact on the cutting surface of a diamond abrasive tool and its contact zone in the processes of machining (review)
(Національний технічний університет "Харківський політехнічний інститут", 2023) Lavrinenko, Valerii; Fedorovich, Vladimir; Ostroverkh, Yevgeniy; Solod, Volodymyr
This article provides information on modern developments in the direction of directed impact on the cutting surface of a diamond-abrasive tool and its contact zone in machining processes. For the most part, such processing is faced with issues of influence on the cutting surface of diamond tools, including ruling mechanical and electrophysical, taking into account the defectiveness of the diamonds that undergo processing, the directed influence on the surface of such diamonds, thermal and modification of the surface of diamonds. Such developments make it possible to significantly intensify processing processes and increase the efficiency of the diamond abrasive tool. That is why, in this review, the main attention is paid to the presentation of modern developments, known from scientific publications, mainly for the last 5 years, related to the above-mentioned issues.
Determination of reliable area sizes for 3D roughness measurement
(Національний технічний університет "Харківський політехнічний інститут", 2023) Zaghal, Jawad; Benke, Márton
Surface roughness characterization plays an important role in the qualification of machined surfaces. As a result of the development of high resolution 3D scanning techniques, researchers and technologists have more possibilities to analyze surface topography in a more detailed way. The purpose of this study is determining the minimal measurement area size of surfaces hard machined by single-point and abrasive tools. Some important height parameters were analyzed: Sa, Sq, Sp, Sv, Ssk and Sku. It was found that the minimum area sizes vary for the different roughness parameters, however, in several cases minimization is possible, depending on the purpose of the surface analytics.

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