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Journal articles on the topic 'Double-sided grinding'
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1
Zhou, Hai, Xiao Ming Xu, Xiang Gao, and Huan Feng. "Research on Subsurface Damage Layer Detection during Substrate Processing." Advanced Materials Research 797 (September 2013): 673–78. http://dx.doi.org/10.4028/www.scientific.net/amr.797.673.
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Double-substrate angle polishing is presented for detecting depth of sub-surface damage layer during sapphire substrate grind process. Bimorph overlap bond is used in the double-substrate angle polishing, and when measuring the beveled corrosion crack, measurement errors caused by the traditional angle polish which results in fussy boundaries between polished bevel and the edge of the original wafer plane is avoided. Also digital length measurement is used to measure specimens polished bevel machining contours, then calculate accurate slant angles, eliminate errors of inaccurate angle values and improve measurement accuracy. This experiment has tested the length of mono-crystal polished bevel crack is 175um, the angle of slant is 4.85°. According to theoretical calculation, the double-sided grinding substrate subsurface damage layer is 15um, and the depth of double-sided crystal surface is about 30um. Grinding parameters: 320# boron carbide aqueous solution, lapping pressure 110g/cm2, grinding speed 30r/min.
2
Nikitina, I., and A. Polyakov. "SPECIFIC FEATURES OF THERMAL PROCESSES IN DOUBLE-SIDED FACE GRINDING MACHINES." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 6, no. 1 (2021): 82–94. http://dx.doi.org/10.34031/2071-7318-2021-6-1-82-94.
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The paper presents an analysis of thermal processes in the bearing system of a double-sided face grinding machine. Experimental data on temperatures and displacements obtained when the machine is idling and when imitating the grinding process with the help of electric heaters of various powers are used for analysis. The performed studies have shown that thermal deformations of double-sided face grinding machines with an arc trajectory of workpiece feed occur in a wide range in magnitude and direction. It can violate the main requirement for the precise operation of the machine - the symmetry of processing conditions at both ends of the workpiece. From the experiments, the absolute value of the non-parallelism of the grinding wheels after three hours of operation is established; it is almost twice the value of the removed allowance. Analysis of the kinetic change in the deformations of the supporting system of the machine tool during operation under thermal load shows that as it warms up, the relative position of the grinding wheels gradually changes from the state "wider at the bottom" to the state "narrower below". This leads to a spontaneous change in the dynamic tuning of the technological system and a corresponding change in the processing accuracy. Changes in the dynamic tuning of the technological system with varying intensity continue throughout the entire operating time of the machine.
3
Nikitina, I. P., and A. N. Polyakov. "Experimental study of double-sided face grinding machine tool." Journal of Physics: Conference Series 1399 (December 2019): 044026. http://dx.doi.org/10.1088/1742-6596/1399/4/044026.
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Lytvyn, Oleksandr, and Kalchenko Dmytro Kalchenko. "INVESTIGATION OF THE PROCESS OF DOUBLE-SIDED GRINDING OF TORCHES OF PUSHERS WITH DIFFERENT DIAMETRERS." TECHNICAL SCIENCES AND TECHNOLOG IES, no. 2 (12) (2018): 86–93. http://dx.doi.org/10.25140/2411-5363-2018-2(12)-86-93.
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Urgency of the research. In machine tools, automotive, agricultural engineering, manufacturing, where it is necessary to ensure high accuracy of surfaces of parts with different diameters of faces, it is required to adhere to high requirements for the quality of geometric sizes, roughness and accuracy of molding. Target setting. Grinding of end surfaces of parts with different diameters of faces, is carried out on two-sided end-grinding machines. The specific gravity of grinding in the total complexity of mechanical processing is constantly increasing and at the present stage it is about 30 % in the machine tool industry, in the automotive industry more than 38% of the total complexity of processing. Actual scientific researches and issues analysis. On the two-sided end-grinding machines of the Saturn company (Germany) the processing of round ends of parts is done with a circular feed to the processing area. Abrasive wheels are used without calibrating plots, which requires a lot of processing to obtain the required precision, which reduces the productivity of grinding. The disadvantage of the method is that the processing of parts with different face diameters is not considered. Uninvestigated parts of general matters defining. It is necessary to improve the processing efficiency of parts by developing the methods of two-sided polishing of the ends of pushers with different diameters oriented grinding wheels with and with-out calibrating sections, and also the rotation or without rotation of the workpiece on the calibration section, at least one revo-lution. The research objective. Improving the accuracy of finishing the end surfaces of parts of various diameters with grinding wheels, is achieved by the fact that the shaping of the ends of the smaller diameter is performed by the maximum diameter of the flat end of one circle, and the shaping of the end face of a larger diameter – the calibration section of the second circle, the length of which is equal to the diameter of the larger end and filled with diamond pencil, which moves along a radius, which coincides with the radius of the location of the axes of the parts in the feed drum. The statement of basic materials. In order to ensure the processing of parts in one pass and the necessary precision of processing, in large-scale and mass production, a grinding method oriented circles with calibrated sections with one-sided arrangement of ends of one diameter is used. The calibration sections are then made of different lengths, depending on the diameter, respectively, larger and smaller. Conclusions. The universal method of practical application of model of accuracy of shaping of ends of parts of different diameters, oriented grinding circles with and without calibration plots has been suggested. The presented method simplifies the grinding of the grinding wheel. It does not require special editing and allows to use regular editing.
5
Wu, Nan Xing, Fei Cheng, and Da Hai Liao. "Finite Element Contact Analysis and Life Analysis of Gears in the Double-Sided Grinding Machine." Applied Mechanics and Materials 778 (July 2015): 218–21. http://dx.doi.org/10.4028/www.scientific.net/amm.778.218.
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The contact fatigue life of gears has direct influences on the working life of the double-sided grinding machine, in the actual using process, the contact fatigue life of gears cannot meet the requirements of working because of many factors. This paper uses the finite element software ANSYS, establishs the two-dimensional model of gears, and analyzes and calculates it, the research shows that: life expectancy of gears is 2.13 years, so gears should have carburizing or carbonitriding heat treatment to fit process requirements, gears can live up to 5.82 years, it can fit the technological requirements of gear life of 5 years. It is some practical value for increasing the working life of the double-sided grinding machine and improving the stability and accuracy of the whole machine.
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Volodymyr, Kalchenko, Kalchenko Vitalіі, Kolohoida Antonina, Yeroshenko Andrii, and Kalchenko Dmytro. "Building a model of dressing the working surfaces of wheels during the two-side grinding of round end faces at CNC machines." Eastern-European Journal of Enterprise Technologies 1, no. 1 (115) (2022): 86–93. https://doi.org/10.15587/1729-4061.2022.252642.
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This paper reports the spatial mathematical modeling of the process of dressing the working surface of grinding wheels for implementing the double-sided grinding of the ends of cylindrical components. Parts with high-precision end surfaces that are commonly used include bearing rollers, piston fingers, crosspieces of cardan shafts, and others. The geometric accuracy of surfaces is ensured by simultaneously grinding the ends at two-sided end-grinding machines with crossed axes of the part and wheels that operate under a self-blunting mode. Before starting the machining, the wheels are dressed in a working position. Moreover, the total orientation angle of the tools is selected subject to the condition of uniform distribution of allowance along the rough sections of wheels. Dressing involves a single-crystal diamond tool with a variable feed. That ensures different development of the surface of abrasive tools, which prolongs their operating time between dressings and improves overall stability. The constant size of micro irregularities at the calibration site enhances the quality of machining. The calibration site is made in the form of a straight line belonging to the plane that passes through the axis of rotation of the wheel and is perpendicular to the plane of the machined part. Based on the spatial mathematical models of the processes of removal of allowance and shape formation when dressing the wheel, the surface of the grinding wheel was investigated. Mathematical models for shaping the ends of parts when grinding with wheels with conical calibration sites have been proposed; it is shown that when applying the proposed machining scheme, there is no geometric error in the size of the part. In addition, due to the uniform distribution of the allowance along the rough area of the wheel, the quality of the surface layer of the ends of parts increases. The devised method for dressing the working surface of wheels could be used to grind the ends of non-circular components.
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Volodymyr, Kalchenko, Kalchenko Vitalіі, Kolohoida Antonina, Kalchenko Olga, and Kalchenko Dmytro. "Building a model of the process of shaping tapered calibrating areas of wheels at the two-sided grinding of round ends." Eastern-European Journal of Enterprise Technologies 2, no. 1 (116) (2022): 62–70. https://doi.org/10.15587/1729-4061.2022.253660.
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This paper reports the spatial modeling of the dressing process of grinding wheels with a conical calibration area to enable two-sided end grinding of cylindrical parts. Components with cylindrical end surfaces are common in the industry, for example, bearing rollers, crosses, piston fingers, and others. High requirements are put forward for the accuracy and quality of the end surfaces. The most efficient is to machine them simultaneously on a double-sided face grinding machine. To improve the quality, grinding is carried out by oriented wheels. The wheel’s angle of rotation in the vertical plane is chosen subject to the uniform distribution of the allowance along a working surface; this makes it possible to reduce the temperature in the cutting zone and improve machining conditions. To improve the accuracy, grinding wheels are provided with a conical calibration area whose rectilinear generatrix is in the plane passing through the axis of wheel rotation and is perpendicular to the end of the part. The minimum permissible length of the calibration area depends on the diameter of the parts being machined; that makes it possible to utilize the work surface more efficiently. Two wheels are dressed simultaneously using diamond pencils that are symmetrically installed in a part feed drum. The angular velocity when dressing the rough area of the wheel is constant, which ensures its different development, and it gradually decreases when dressing the calibration area to provide for its constant roughness. In general, this prolongs the resource of grinding wheels and the quality of machining. The wheels are given axial movement to ensure the straightness of the cone calibration area. The dressing technique reported here can be used on machines equipped with a numerical software control system and without it. It could also be applied in the machining of parts with non-round ends
8
Wang, Lijuan, Zhongwei Hu, Yiqing Yu, and Xipeng Xu. "Evaluation of Double-Sided Planetary Grinding Using Diamond Wheels for Sapphire Substrates." Crystals 8, no. 7 (2018): 262. http://dx.doi.org/10.3390/cryst8070262.
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Nikitina, I., A. Polyakov, and D. Voronin. "EXPERIMENTAL MEASURES TO IMPROVE THERMAL CHARACTERISTICS IN DOUBLE-SIDED FACE GRINDING MACHINES." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 7, no. 9 (2022): 116–26. http://dx.doi.org/10.34031/2071-7318-2022-7-9-116-126.
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The results of full-scale and computational experiments to improve the thermal characteristics of the machine tool are presented. This can lead to a decrease or achieve symmetry of the resulting thermal deformations. The implementation of four schemes for the redistribution of heat fluxes is considered: the heat flux of the main electric motors, directed under the protective casing of the drive pulley, and the heat flux of the belt drive are removed through special windows in the casing to the environment; jointly with the first scheme of redistribution of heat fluxes, cooling of the ends of the grinding headstocks is provided with the help of an impeller fixed on each drive pulley; jointly with the second scheme, heat flux isolation from the left and right electric motors is provided; heating the ends of the machine tool bed. The first three schemes are implemented at idling of the machine tool; the fourth scheme is implemented when the machine is operating under thermal load. The joint implementation of three schemes makes it possible to reduce the displacement of the right circle at idle by 1.5 times, the left circle practically did not move. The test of the first three circuits during the operation of the machine tool under a thermal load does not reveal significant changes in the thermal characteristics. The implementation of the fourth heat flux redistribution scheme help to compensate for thermal deformations from heating in the central part of the bed and reduce changes in the angular position of the grinding wheels.
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Kalchenko, Volodymyr, Dmytro Kalchenko, Volodymyr Venzhega та Sergiy Ryabov. "ПІДВИЩЕННЯ ТОЧНОСТІ ТА ПРОДУКТИВНОСТІ ОБРОБКИ ТОРЦІВ РОЛИКІВ ПІДШИПНИКІВ КОЧЕННЯ". TECHNICAL SCIENCES AND TECHNOLOGIES, № 3(17) (2019): 9–17. http://dx.doi.org/10.25140/10.25140/2411-5363-2019-3(17)-9-17.
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Urgency of the research. High-precision and productive machining of the ends of the rollers of the roller bearings is an urgent and important scientific and practical task, the solution of which will allow both to prolong the life of the bearings and to reduce their production, and therefore to increase the level of competitiveness of production. Target setting. The main requirements relating to the rollers of the rolling bearings are to ensure the high accuracy of size, shape, quality of end surfaces with high productivity of the machining process. Actual scientific researches and issues analysis. The main directions of improving the accuracy and productivity of two-sided grinding are to increase the rigidity of the machine-tool-tool-part system, to reduce the thermal impact, to improve the kinematic characteristics of the workpiece movement in the treatment area, to optimize the design and characteristics of grinding wheels. Uninvestigated parts of general matters defining. One of the most promising areas for improving the accuracy and productivity of the double-sided grinding process is to use the effect of crossing axes of grinding wheels and billets with special tool profiling. The purpose of the article. To analyze the factors that affect the accuracy and productivity of machining the end surfaces of parts on two-sided grinding machines and to develop a new high-performance method of processing the end surfaces of the rollers of the roller bearings, which would provide the possibility of assembly between the rolling bodies and the rings, not by a selective method. The presentation of the main material. The combined editing of the two planes of grinding wheels on two-sided grinding machines enables to obtain a larger diameter of the calibration section. In this case, the entire allowance is cut off in the area adjacent to the gauge. The calibration section at the inlet of the parts in the treatment area does not participate in cutting off the seam allowance, has high stability and at the outlet forms the final accuracy of the end surfaces. Conclusions and suggestions. The paper proposes a new high-performance method of single-pass machining of the end surfaces of the rollers of the roller bearings on two-sided grinding machines with oriented grinding wheels, which have a calibration section, which ensures high accuracy of processing. This method allows to reduce the scattering range of sizes and to go to the method of complete interchangeability when assembling the bearing units.
11
Nikitina, I., A. Polyakov, and D. Voronin. "SIMULATION OF THE THERMAL DEFORMATION BEHAVIOR OF DOUBLE SIDED FACE GRINDERS." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 7, no. 1 (2022): 90–101. http://dx.doi.org/10.34031/2071-7318-2021-7-1-90-101.
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The paper presents the result of modeling the thermal deformation behavior of the bearing system of a double-sided face grinder. Two modes of its operation is considered: idling and working strokes. Spindle bearings, heat fluxes from coolant, and heat fluxes from motors are considered as the main heat sources. The preliminary values of heat and convective fluxes are assigned according to well-known methods used in engineering calculations of machine tools. Refinement of the values of heat and convective fluxes is carried out according to the results of experimental values of temperatures and temperature displacements. In the thermal model, convective heat transfer is assigned to 450 surfaces. Heat flows are assigned to 161 surfaces. The simulation is run in Ansys for 6 hours of machine tool operation. Ansys uses a ten-node Solid227 element as a typical finite element. The problem of thermoelasticity is solved in a related setting. The error in modeling thermal processes did not exceed 0,5 degree, the error in modeling temperature displacements did not exceed 5 microns. The results of computer simulation confirmed the relative experimental positions of the left and right grinding wheels characteristic of this range of machines. At idle, the relative position of the grinding wheels represented the state «wider at the bottom», and during the working stroke, the state «at the bottom narrower» is recorded. The illustrations of the FEM model and contour plots for the temperature field and temperature displacements of the bearing system of the machine tool for two modes of its operation are presented.
12
Kozeruk, A. S., V. V. Safonov, M. I. Filonova, V. O. Kuznechik та V. I. Yurinok. "Double-Sided Processing оf Low-Hardness Lenses". Science & Technique 24, № 1 (2025): 33–39. https://doi.org/10.21122/2227-1031-2025-24-1-33-39.
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The scheme of a device for processing lenses with convex-concave spherical surfaces of the negative meniscus type of average diameter, which allows flexible and wide control over the process of simultaneous bilateral abrasive shaping of the noted optical parts, is considered in the paper. Mathematical modeling of the processing of spherical surfaces using the free grinding method using a tool in the form of a mushroom and a cup was carried out. An analytical expression is obtained for calculating cutting paths, which, according to F. Preston’s formula, are proportional to the amount of material removed from the work-piece being processed. The calculation of cutting paths in the diametrical sections of the processed spherical surfaces was carried out. The calculation was performed for various values of such parameters of processing modes as the amplitude of the reciprocating rotational movement of the tools and the number of their double strokes per minute, as well as the rotation speed of the lens. In this case, the section with the greatest divergence of sliding paths was considered and the relative value of these paths was determined, which is proportional to the processing accuracy. Research has been carried out to establish that when correcting macro-errors on the actuating surface of the lens, it is most effective to change the amplitude of the reciprocating rotational movement of the tools, and these changes should be made within the range from the minimum value of this amplitude, determined by the design features of the specific basic technological equipment, to its value 0.65 of the diameter of the work-piece. In this case, to minimize local errors of the latter, it is advisable to set its rotation speed to 60–70 rpm.
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Mahamad Sahab, Abdul Rahim, Nor Hayati Saad, Amirul Abdul Rashid, et al. "Effect of Double Sided Process Parameters in Lapping Silicon Wafer." Applied Mechanics and Materials 393 (September 2013): 259–65. http://dx.doi.org/10.4028/www.scientific.net/amm.393.259.
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Silicon wafer is widely used in semiconductor industries for development of sensors and integrated circuit in computer, cell phones and wide variety of other devices. Demand on the device performance requires flatter wafer surface, and less dimensional wafer variation. Prime silicon wafer is hard and brittle material. Due to its properties, double sided lapping machine with ceramic grinding agent were introduced for machining high quality standard silicon wafers. The main focus is the silicon wafer with high accuracy of flatness; to reduce total thickness variation, waviness and roughness. In this paper the lapping experiment and analysis showed that the double sided lapping machine is able to produce total thickness variation less than 10 um at controlled process parameters within short processing time. Machining using low mode method reduced the total thickness variation (TTV) value. The lapping load and speed directly reflected the performance and condition of final silicon wafer quality.
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Chen, Gen, Zhongwei Hu, Lijuan Wang, and Yue Chen. "Modeling of Material Removal Rate for the Fixed-Abrasive Double-Sided Planetary Grinding of a Sapphire Substrate." Materials 17, no. 15 (2024): 3688. http://dx.doi.org/10.3390/ma17153688.
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Double-sided planetary grinding (DSPG) with a fixed abrasive is widely used in sapphire substrate processing. Compared with conventional free abrasive grinding, it has the advantages of high precision, high efficiency, and environmental protection. In this study, we propose a material removal rate (MRR) model specific to the fixed-abrasive DSPG process for sapphire substrates, grounded in the trajectory length of abrasive particles. In this paper, the material removal rate model is obtained after focusing on the theoretical analysis of the effective number of abrasive grains, the indentation depth of a single abrasive grain, the length of the abrasive grain trajectory, and the groove repetition rate. To validate this model, experiments were conducted on sapphire substrates using a DSPG machine. Theoretical predictions of the material removal rate were then juxtaposed with experimental outcomes across varying grinding pressures and rotational speeds. The trends between theoretical and experimental values showed remarkable consistency, with deviations ranging between 0.2% and 39.2%, thereby substantiating the model’s validity. Moreover, leveraging the insights from this model, we optimized the disparity in the material removal rate between two surfaces of the substrate, thereby enhancing the uniformity of the machining process across both surfaces.
15
Hasegawa, Yuhji, Takashi Sasaki, Nobuhide Itoh, and Hitoshi Ohmori. "Characteristics of ELID-lap Grinding for Double Sided : Characteristics of ELID pre-dressing." Proceedings of Yamanashi District Conference 2002 (2002): 121–22. http://dx.doi.org/10.1299/jsmeyamanashi.2002.121.
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Wang, Lijuan, Zhongwei Hu, Congfu Fang, Yiqing Yu, and Xipeng Xu. "Study on the double-sided grinding of sapphire substrates with the trajectory method." Precision Engineering 51 (January 2018): 308–18. http://dx.doi.org/10.1016/j.precisioneng.2017.09.001.
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Kalchenko, Volodymyr, Andriy Yeroshenko, Volodymyr Venzhega, and Dmytro Kalchenko. "EXPERIMENTAL STUDIES OF GRINDING OF THE ENDS OF BEARING ROLLERS ON THE MODERNIZED TWO-SIDED END GRINDING MACHINE 3342ADO." Technical Sciences and Technologies, no. 3(29) (2022): 67–76. http://dx.doi.org/10.25140/2411-5363-2022-3(29)-67-76.
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Rolling bearing rollers are very important components of rolling bearings, the end surfaces of which are processed in mass and serial production on two-sided end grinding machines. They must be manufactured in accordance with the require-ments of GOST 25255-82 "Rolling bearings. Rollers cylindrical long. Technical conditions" made of bearing steel ShKh 15 according to GOST 801-78. The end surfaces of the rollers of rolling bearings are subject to high requirements for the accuracy of dimensions, shape and quality of the end surfaces while ensuring high processing productivity. Therefore, it is very important to find new reserves of the process.The analysis of research and publications showed the importance of the thermal effect and rotation of the workpieces in the processing zone during double-sided face grinding on the productivity, accuracy and quality of the processed end surfaces. This becomes even more important when grinding with crossed axes of wheelsand workpieces, since a special profile adjust-ment of the wheel is carried out, which makes it possible to obtain an area for removing the rough allowance and a calibration area on the surface of the wheel. At the same time, the entire allowance is cut inthe area adjacent to the calibration area. The calibration area at the entrance of the parts to the processing area does not participate in cutting the allowance, has high stability and forms the final accuracy of the end surfaces at the exit.The purposeof the article is to conduct experimental studies of the temperature on the ends of the machined bearing rollers along the processing coordinate and the rotation of the machined rollers in the closed zone between two grinding wheels along the processing coordinate on a modernized end-grinding machine 3342 ADO.The work proposed for the first time a new way of adjusting grinding wheels on a two-sided face grinding machine 3342 ADO, which made it possible to obtain a calibration area of grinding wheels of the correct geometric shape (without concavity). For this, the system of straightening of the basic face grinding machine 3342 ADO was modernized, which ensured the syn-chronization of the movements of the product feeding disc with the diamond pencil located on it for straightening the calibration area and the movement along the axis of the headstock of the rotating grinding wheel. All movements were controlled by the CNC system with a specially developed control program.
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Kalchenko, Volodymyr, Vitalіі Kalchenko, Antonina Kolohoida, Olga Kalchenko, and Dmytro Kalchenko. "Building a model of the process of shaping tapered calibrating areas of wheels at the two-sided grinding of round ends." Eastern-European Journal of Enterprise Technologies 2, no. 1 (116) (2022): 62–70. http://dx.doi.org/10.15587/1729-4061.2022.253660.
Full textAbstract:
This paper reports the spatial modeling of the dressing process of grinding wheels with a conical calibration area to enable two-sided end grinding of cylindrical parts. Components with cylindrical end surfaces are common in the industry, for example, bearing rollers, crosses, piston fingers, and others. High requirements are put forward for the accuracy and quality of the end surfaces. The most efficient is to machine them simultaneously on a double-sided face grinding machine. To improve the quality, grinding is carried out by oriented wheels. The wheel’s angle of rotation in the vertical plane is chosen subject to the uniform distribution of the allowance along a working surface; this makes it possible to reduce the temperature in the cutting zone and improve machining conditions. To improve the accuracy, grinding wheels are provided with a conical calibration area whose rectilinear generatrix is in the plane passing through the axis of wheel rotation and is perpendicular to the end of the part. The minimum permissible length of the calibration area depends on the diameter of the parts being machined; that makes it possible to utilize the work surface more efficiently. Two wheels are dressed simultaneously using diamond pencils that are symmetrically installed in a part feed drum. The angular velocity when dressing the rough area of the wheel is constant, which ensures its different development, and it gradually decreases when dressing the calibration area to provide for its constant roughness. In general, this prolongs the resource of grinding wheels and the quality of machining. The wheels are given axial movement to ensure the straightness of the cone calibration area. The dressing technique reported here can be used on machines equipped with a numerical software control system and without it. It could also be applied in the machining of parts with non-round ends
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Song, De Bo, Xiang Long Zhu, Ren Ke Kang, Zhu Ji Jin, Shuang Ji Shi, and Bi Zhang. "Experimental Research on Dressing Parameters of the Plate in Planetary Double-Sided Grinding Process." Materials Science Forum 874 (October 2016): 172–77. http://dx.doi.org/10.4028/www.scientific.net/msf.874.172.
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Dressing parameters, which directly affect the flatness of the plate, are very important in planetary double-sided grinding dressing process. In this paper, trajectory and velocity equations of grit are studied. By comparing to the trajectory density of different annular regions, this paper puts forward an evaluation method of the shape of the plate and explores the impact of rotation speed on the shape of the plate. Finally, the experiments are performed by adjusting the rotation speed of the sun wheel and the plate. The results show that the flatness of the plate can be dressed below 0.01 mm, which validates the correctness of the theory.
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Volkov, D. I., and B. V. Tsvetkov. "Double-Sided Deep Grinding of Gas Turbine Engine Blades with Highly Porous CBN Tools." Russian Engineering Research 43, no. 12 (2023): 1499–503. http://dx.doi.org/10.3103/s1068798x2312033x.
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Kalchenko, Volodymyr, Vitalіі Kalchenko, Antonina Kolohoida, Andrii Yeroshenko, and Dmytro Kalchenko. "Building a model of dressing the working surfaces of wheels during the two-side grinding of round end faces at CNC machines." Eastern-European Journal of Enterprise Technologies 1, no. 1 (115) (2022): 86–93. http://dx.doi.org/10.15587/1729-4061.2022.252642.
Full textAbstract:
This paper reports the spatial mathematical modeling of the process of dressing the working surface of grinding wheels for implementing the double-sided grinding of the ends of cylindrical components. Parts with high-precision end surfaces that are commonly used include bearing rollers, piston fingers, crosspieces of cardan shafts, and others. The geometric accuracy of surfaces is ensured by simultaneously grinding the ends at two-sided end-grinding machines with crossed axes of the part and wheels that operate under a self-blunting mode. Before starting the machining, the wheels are dressed in a working position. Moreover, the total orientation angle of the tools is selected subject to the condition of uniform distribution of allowance along the rough sections of wheels. Dressing involves a single-crystal diamond tool with a variable feed. That ensures different development of the surface of abrasive tools, which prolongs their operating time between dressings and improves overall stability. The constant size of micro irregularities at the calibration site enhances the quality of machining. The calibration site is made in the form of a straight line belonging to the plane that passes through the axis of rotation of the wheel and is perpendicular to the plane of the machined part. Based on the spatial mathematical models of the processes of removal of allowance and shape formation when dressing the wheel, the surface of the grinding wheel was investigated. Mathematical models for shaping the ends of parts when grinding with wheels with conical calibration sites have been proposed; it is shown that when applying the proposed machining scheme, there is no geometric error in the size of the part. In addition, due to the uniform distribution of the allowance along the rough area of the wheel, the quality of the surface layer of the ends of parts increases. The devised method for dressing the working surface of wheels could be used to grind the ends of non-circular components.
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Wang, Lijuan, Zhongwei Hu, Yue Chen, Yiqing Yu, and Xipeng Xu. "Material removal mechanism of sapphire substrates with four crystal orientations by double-sided planetary grinding." Ceramics International 46, no. 6 (2020): 7813–22. http://dx.doi.org/10.1016/j.ceramint.2019.11.284.
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Li, Qingliang, Shichao Xiu, Cong Sun, Yunlong Yao, and Xiangna Kong. "Analysis of the uniformity of material removal in double-sided grinding based on thermal–mechanical coupling." International Journal of Advanced Manufacturing Technology 119, no. 5-6 (2022): 3363–75. http://dx.doi.org/10.1007/s00170-021-08457-6.
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Kozeruk, A. S., Y. L. Malpica, M. I. Filonova, V. I. Shamkalovich, and R. O. Dias Gonzalez. "MATHEMATICAL MODELING OF OPERATIONAL ZONE FOR TECHNOLOGICAL EQUIPMENT USED FOR DOUBLE-SIDED PROCESSING OF LENSES." Science & Technique 17, no. 3 (2018): 204–10. http://dx.doi.org/10.21122/2227-1031-2018-17-3-204-210.
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A mathematical modeling of geometric and kinematic relations has been made in respect of an operational zone for one of the standard machine tool sections which is used for simultaneous double-sided abrasive processing of highly-accurate lenses with a small rigidity (with a thin centre) under free lapping conditions. An analytical expression has been obtained for calculation of a sliding velocity in an arbitrarily selected point either on a surface to be processed or on a processing surface. As the proposed technology for simultaneous double-sided processing presupposes oscillatory motion of only processing tools then in order to eliminate a joint opening (a local contact fault between lapping surfaces of a tool and a work-piece) length of a drive piece must be not less than a specified value. In this case a convex tool is rigidly connected with a drive piece and it makes a reversing rotary motion (an oscillatory motion) around a centre of the processed spherical surface and a hinged joint of the centre with an output element of the technological equipment actuation mechanism is realized by transition of the drive piece ball end with a spherical seat in the output unit. In order to reveal analytical dependence of tool drive piece length on radius value of the processed spherical lens surface and friction coefficient in the contact zone of the tool and a work-piece the paper has considered a flow pattern of force while processing concave surfaces of lenses having small radius of curvature in case when the tool is positioned at the top. The friction coefficient included in the obtained expression has been determined for grinding while using suspensions of М40, М28, М10 micro-powders in a cast-iron grinding instrument and polishing while using polyrhythm suspension in a pitch and urethane-foam polisher. A method of the inclined plane has been used in this case and following the method a work-piece of optical glass has been initially lapped to the tool with the help of the appropriate abrasive suspension and the required angle has been determined at the moment when the work-piece started its sliding movement along the tool surface.
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Kalchenko, Volodymyr, Volodymyr Venzhega, Yaroslav Kuzhelnyi, and Valeriy Klimenko. "Technological methods of improving the quality and productivity of processing car engine parts." Automobile transport, no. 52 (July 26, 2023): 25–31. http://dx.doi.org/10.30977/at.2219-8342.2023.52.0.03.
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Problem. The most high-precision parts of the car engine are camshaft and crankshaft, parts that require two-sided processing of the end surfaces: piston pins, valve springs. Traditional processing methods are used in their manufacture and repair. Therefore, taking into account the large volumes of car production, the improvement of existing and development of new processing methods is very important. Goal. The purpose of this work is the analysis and improvement of existing methods and the implementation for new ones of processing the specified parts to increase the productivity and accuracy of their processing. Methodology. The processing of support necks and cams is expedient to be carried out in one installation during deep high-speed grinding with crossed axes of the circle and camshaft due to stabilization of the cutting depth and feed along the contour with uneven rotation of the part. The method of high-speed milling of camshaft cams with crossed axes of the tool and parts on CNC machines is also promising. Root and connecting rod necks of crankshafts can be processed in one installation by deep high-speed grinding with crossed axes of the circle and the part due to stabilization of the depth of cutting and feed along the contour with uniform rotation of the part. For end surfaces, it is possible to introduce single-pass processing on double-sided end grinding machines with oriented grinding wheels with calibration areas. Results. The obtained results indicate a 25-30% increase in productivity and processing accuracy of the specified parts. Originality. It is used when processing the effect of the intersection of the axes of the tool and the part and carrying out a special correction of the tool, which allows to obtain a calibration area. Practical value. The proposed methods improve the parameters of accuracy, roughness and productivity of processing, which is an important scientific and practical task, whose solution will allow to increase the service life of car components and assemblies, reduce the cost of their production, and raise the level of competitiveness of products and services.
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Kalchenko D., D. "Theoretical and experimental study of double-sided grinding process of round face ends by orientated wheels with calibrating sections." Scientific journal of the Ternopil national technical university 89, no. 1 (2018): 100–112. http://dx.doi.org/10.33108/visnyk_tntu2018.01.100.
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Kamchatna-Stepanova, Kateryna, and Oleksandr Klochko. "MODERN METHODS OF GEAR MILLING OF HARDENED LARGE-MODULE GEARS." Scientific Journal of Polonia University 43, no. 6 (2021): 312–23. http://dx.doi.org/10.23856/4340.
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The latest developments of modern methods of high-speed gear milling of large-module cylindrical gears, both for preliminary grinding of teeth and for final blade processing of gears, are considered. For high-speed blade gear processing, promising designs of worm carbide cutters have been developed, manufactured and implemented. The technological regulations of blade gear processing for the operation of each of the design solutions of worm carbide cutters have been developed. The design of a special double-body worm cutter for double-sided cutting has been developed. It is shown that the carbide cutting elements of the milling cutters, which are placed only along the lines of the machine engagement of the tool and the workpiece, make it more economical compared to the known designs of similar tools. The application of the developed technological methods of pre-blade processing of the teeth of hardened wheels with carbide cutters reduces the labor intensity of low-performance gear grinding operations, depending on the wheel module, by 3-4 times by reducing the allowance from 1.5–2.5 mm on the tooth side to 0.3–0.5 mm, and also allows you to ensure the gear processing process is economical by reducing the consumption of carbide plates. The developed technological studies of ensuring the quality of gear processing of large-module cylindrical wheels allow us to solve the scientific and technical problem associated with the production of large-module gears with high-hardness teeth while improving the quality of their manufacture, reducing labor costs and reducing material consumption.
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Kalchenko, Volodymyr, Volodymyr Venzheha, Oleksandr Lytvyn, and Dmytro Kalchenko. "INVESTIGATION OF THE PROCESS OF TORCHES DOUBLE-SIDED GRINDING OF PUSHERS WITH DIFFERENT DIAMETERS WITH CALIBRATION PARTS AND WITHOUT THEM." TECHNICAL SCIENCES AND TECHNOLOG IES, no. 1(11) (2018): 25–31. http://dx.doi.org/10.25140/2411-5363-2018-1(11)-25-31.
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Khan, Muhammad Saleem, Zenab Qayyum, Aneela Wakeel, and Muhammad Adil. "Selection of Joint Preparation Procedure based on Cost-effectiveness and Defects analysis of Double-V SMAW Joint." International Journal of Advanced Natural Sciences and Engineering Researches 7, no. 5 (2023): 117–24. http://dx.doi.org/10.59287/ijanser.912.
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Double sided shielded metal arc welded joint has wide applications in fabrication sector for production of critical joints but the root pass in those joint leads to many defects, mainly due to the sudden cooling because the adjacent base material is at room temperature in the start of welding and compromises the quality of the weldments. In the fabrication industry, root pass removal is a routine practice for producing quality joints using grinding and air carbon arc gouging. In this research, comparative study of cost-effectiveness and defects analysis of the above root pass removal procedures have applied to the double-v mild steel shielded metal arc welded joint for the selection of better procedure. For cost calculation of joints, labor cost (LC), energy cost (EC), material cost (MC) and overhead cost taken into account and defects examined by the visual inspection, liquid penetrant test, radiographic test and optical microscope. The results showed overall 4.7% lower cost and enhanced quality in terms of macro/micro-defects for ground joint. The major contribution to the lower cost of ground joint has given by the consumables and energy but in defects analysis, only width difference in both sides’ reinforcement i.e., front and back have observed for gouged joint and relatively more numbers of micro-defects.
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Kalchenko, Dmytro. "THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF THE PROCESS OF DOUBLE-SIDED GRINDING THE END FACES WITH SKEW AXES OF CYLINDRICAL PARTS, AND CIRCLES WITH CALIBRATED PARTS." TECHNICAL SCIENCES AND TECHNOLOG IES, no. 4(10) (2017): 44–53. http://dx.doi.org/10.25140/2411-5363-2017-4(10)-44-53.
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Serikov, Yu B. "Stone inventory of the site complex “Koksharovsky Hill sanctuary — Yuryinskoe settle-ment” (based on materials of excavations in 2013 and 2015)." VESTNIK ARHEOLOGII, ANTROPOLOGII I ETNOGRAFII, no. 1(64) (March 15, 2024): 5–18. http://dx.doi.org/10.20874/2071-0437-2024-64-1-1.
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The article presents detailed statistical, typological and mineralogical characteristics of stone products from the “Koksharovsky Hill sanctuary — Yuryinskoe settlement” complex of sites derived from the excavations of A.F. Shorin conducted in 2013 and 2015. By these excavations, the eastern part of the sacred space of the sanctuary and the adjacent to it section of the settlement Yuryinskoe were investigated. A noticeable admixture of the Mesolithic (16.35 %), as well as Eneolithic and Bronze Age stone products (1.4 %), was found within the complex. The main body of the stone complex of items belongs to the Neolithic (82 %). The technology of stone knapping was focused on obtaining 1.2–2.1 cm wide plates. The plates were processed mainly by ventral retouching, and they served as the initial semi-finished product for manufacturing knives, arrowheads, scrapers and points. Double-sided retouching was used to process arrowheads and knives. Adzes, axes and arrowheads were made by means of abrasive technique. Processing tools were represented by hammers, pestles, bumpers, retouchers, abrasives and grinding plates. Talc products were widely used. Non-utilitarian items were represented by two talc and quartzite discs, and a miniature talc “iron”. About 30 types of mineral raw materials, obtained mainly from local sources, were used on the site. Of these products, 30 % have preserved the primary (prevalently tile-like) crust.
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Fedorchenko, A. Yu, M. V. Seletskiy, and A. I. Lebedintsev. "Investigation of Ornamented Bone Items from the Olskaya Site Using Three-Dimensional Modelling." Problems of Archaeology, Ethnography, Anthropology of Siberia and Neighboring Territories 27 (2021): 702–9. http://dx.doi.org/10.17746/2658-6193.2021.27.0702-0709.
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This paper discusses the practical application of three-dimensional modelling technologies in studying bone artefacts with engraved images of the paleometal era. To achieve the study goal, we carried out a comprehensive analysis of the antler crest obtained from excavations at the Olskaya site, one of the key archaeological sites of the Tokarev culture in the Northern Priokhotye. The artefact under discussion has a complex geometric pattern, which made it possible to use it to test various tools of 3D modelling technology. As a result of our research, we reconstructed the operational sequence of the item production, which involved splitting a reindeer antler to obtain a blank, planing, double-sided cutting of teeth, surface preparation by grinding, ornamentation, and perforation. The linear ornamentation on the crest makes up a composition of horizontal motifs as stripes of small rectangles and zigzags made in double lines. 3D scanning technologies made it possible to obtain accurate data on the morphometric parameters of decorative elements, the sequence of their application and the tools used. As a result of our measurements, we found out that the metric characteristics ofwhole rectangles in the ornamented composition differ significantly. The study results showed a minimum difference in the cut lines ’depth, both in rectangles of all rows and diagonal stripes. The revealed features made it possible to assume that one master who used the same tool cut the ornament. The nature of the processing traces shows that the design of the teeth and decoration were made with different tools. The obtained data indicate the presence of specialization in the toolkit of bone carving production and a generally high level of bone processing technologies among the Tokarev culture people.
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Polyakov, A., I. Nikitina, and V. Pozevalkin. "CREATION OF A DIGITAL MODEL OF THE MACHINE TOOL THERMAL DEFORMATION SYSTEM." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 9, no. 11 (2024): 116–31. https://doi.org/10.34031/2071-7318-2024-9-11-116-131.
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The paper presents a methodology for building a digital model of the thermo-deformation system of a machine tool used in the creation of digital twins of machine tools for which their thermoelastic behavior is relevant, based on the solution of the thermoelasticity problem. Ansys Workbench and Ansys Twin Builder platforms are used as special software that allows you to create a digital model. A double-sided face grinding machine was used as an object of modeling, for which experimental studies were conducted ealier. The experimental data allowed us to form the target values of the optimization problem. A general methodology for building a digital model based on the use of the FMI standard for the exchange of dynamic libraries has been developed. The paper shows the practical application of the digital model of the machine tool to solve the problem of identification of the thermo-deformation model of the machine tool. The identification problem was solved in an extremal formulation. The analysis of the effectiveness of the use of six optimization methods is presented: the Quasi-Newton method; Pattern search; Multi-Objective Genetic Algorithm; Mixed-Integer Sequental Quadratic Programming; Adaptive Multiple-Objective; Adaptive Single-Objective. The methods of Mixed-Integer Sequental Quadratic Programming and Adaptive single-Objective were preferred in terms of efficiency. Their application allows to obtain the refined parameters of the model with the error of achieving the target values of modeling less than 2 %.
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Serikov, Yu B. "STONE INVENTORY OF THE CENTRAL PART OF THE SANCTUARY KOKSHAROVSKY HILL (BASED ON THE MATERIALS OF EXCAVATIONS IN 1995 AND 2011)." Вестник Пермского университета. История, no. 1 (64) (2024): 5–25. http://dx.doi.org/10.17072/2219-3111-2024-1-5-25.
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Koksharovsky Hill is the most famous and most studied cult site of the Middle Trans-Urals. It is located within the boundaries of the Yuryinskoie Neolithic settlement on the southern shore of the Koksharovsky peat bog, forming a cohesive unit with it. While ceramic complexes and products of the sacred purpose of the hill have been extensively documented in many publications, the stone inventory has only been partially and selectively published. The article analyzes the complex of stone products from the central part of the Koksharov-sky hill in detail. There is a slight admixture of Mesolithic and Eneolithic on the site, but the main part of the stone inventory (about 90%) belongs to the Neolithic era. The technology of stone splitting was focused on ob-taining plates with a width of 1.0–2.3 cm (69%). Among the plates with secondary processing, those with re-touching from the back are the most prevalent (75%). The preferred raw materials for plate produc-tion were weakly siliceous rocks, such as light gray weakly siliceous rock and siltstone. On the sites of the Koksharovsky peat bog, this raw material can be considered a marker of the Neolithic era. The plates were used as blanks for the manufacture of knives, arrowheads, darts, scrapers, and points. Double-sided retouching was used to process arrowheads and knives, while abrasive techniques were used in the manufacture of axes, adzes, and knives. Other products found on the site include drills, abrasives, lapels, pestles, hammers, fishing sinkers and tool blanks. Of particular note is the presence of 200 fragments of split grinding plates. Their fragmentary nature and quantity clearly indicate the use of grinding plates in certain rituals. As with any cult sites, there are significant series of crushed stone, whole and split pebbles on the hill. The site also contains evidence of the use of about 20 types of mineral raw materials, mainly of local origin. Almost 40% of the products have preserved their primary crust. It should be also noted that a noticeable series of sacred products has been found in the cen-tral part of the hill, including a stone hammer in the form of a beaver's head, fragments of Neolithic vessels with zoomorphic rivets, a clay “ironing” and other clay crafts.
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Kozeruk, A. S., Y. L. Malpica, M. I. Filonova, and V. O. Kuznechik. "Investigations on Stresses in Optical Components with Spherical Surfaces." Science & Technique 18, no. 5 (2019): 416–21. http://dx.doi.org/10.21122/2227-1031-2019-18-5-416-421.
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The paper has substantiated an expediency to fix lenses with a thin center (biconcave, flat concave and negative meniscus) to a non-operational cylindrical surface. This avoids their temperature distortion at the blocking stage which is a reason for occurrence of irremovable micro and macro errors on executive surfaces of a component after its unblocking and it causes astigmatism in an image which is formed by an optical-electronic device. The paper considers a method for attachment of a lens to its side surface and it contains a design description of the device for mechanical attachment of the studied lenses during their simultaneous double-sided abrasive processing under free-grinding conditions. The paper presents a methodology for determination of a stressed state in lenses, which is based on a mathematical model of a uniform elastic isotropic deformation of a solid body. This approach takes into account a finite element method which consists in an approximation of a body under study with the help of a model presenting a set of elements with a finite number of freedom degrees which are interrelated at node points. The investigations have been executed with the purpose to study a nature of deformation distribution in a lens which made it possible to establish a directly proportional dependence of displacements in the center of the part on the magnitude of clamping forces. The paper reveals an insignificant influence of a clamping force magnitude and elastic characteristics of a lens on an optimum position of an application plane of its clamping forces. A non-contact method for monitoring errors on a polished lens surface using an interferometer with a reference front surface has been proposed in the paper.
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Balashov, V. N., S. N. Judaev, and A. A. Gnevashev. "Strong interaction between the workpiece with abrasive wheels of double side grinding." Izvestiya MGTU MAMI 7, no. 2-2 (2013): 242–44. http://dx.doi.org/10.17816/2074-0530-68269.
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This article describes how two-sided grinding in mobile centers. The description of the force interaction of abrasive wheels with the workpiece. The possibility of reducing the elastic strain in bilateral grinding through setting up the machine.
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Яруллин, Фанис, Fanis Yarullin, Равиль Ибятов, et al. "RESULTS OF FIELD STUDIES OF SOIL-TILLAGE TOOLS WITH ELLIPSOVID DISKS." Vestnik of Kazan State Agrarian University 14, no. 2 (2019): 123–27. http://dx.doi.org/10.12737/article_5d3e17361cada0.88786874.
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This paper presents the results of field studies of a rotary tool for soil tillage, consisting of a frame on which is placed a working section in the form of elliptical discs with double-sided grinding. The major axes of the ellipsoid disks are inclined to the axis of rotation. A rotating roller is installed behind the working section to level and compact the field surface. The aim of this work is to substantiate the rational values of the technological parameters of the rotary tool on the basis of experimental studies in field conditions of the soil tillage depth, combing of the treated field surface and the degree of soil crumbling under various operating conditions of the unit. To determine the processing depth and the degree of soil crumbling, standard methods were used. Grating was determined using the device IP-250. As a result of research, it was found that, at a given processing depth of 80 mm and an increase in the speed of movement of the rotary tool to 3.61 m/sec., the ridge surface of the field decreases to 14-15 mm, and then begins to increase. This is explained by the fact that at high speeds the rotational roller does not have time to destroy lumps, which leads to an increase in combing. It was also found that with an increase in the speed of movement up to 3.61 m/sec. and a processing depth of 80 mm, the soil crumbling degree increases to 86-87%, and with a further increase in speed it begins to decrease. This is explained by the fact that at elevated speeds of aggregate’s movement, the working units of the rotary tool begin to deepen from the soil, as a result of which the predetermined depth of tillage and its high crumbling cannot be maintained. Thus, rational values of the speed of a rotary tool’s movement with elliptical disks ranging from 3.33 to 3.88 m/sec., which ensure the fulfillment of agrotechnical requirements for surface tillage, are determined.
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Khot, Tanvi, Priya Lele, Vidya Dodwad, Nishita Bhosale, Manasi Yewale, and Sarah Mariam. "Comparative evaluation of the effectiveness of three commercially available desensitizing mouthwash on dentinal tubule occlusion: An in vitro scanning electron microscopic study." Journal of International Society of Preventive and Community Dentistry 13, no. 5 (2023): 426–32. http://dx.doi.org/10.4103/jispcd.jispcd_97_23.
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Abstract Aim: To compare and evaluate the effectiveness of three commercially available desensitizing mouthwashes on dentinal tubule occlusion in vitro using a scanning electron microscope (SEM). Materials and Methods: Twenty-seven premolar maxillary teeth were collected and cleaned to remove debris and tissue using an ultrasonic scaler. Enamel was removed with the help of a high-speed plain cut tungsten carbide fissure bur under continuous water spray. Dentinal discs measuring 5 mm × 5 mm × 3 mm were prepared from the coronal region of the extracted teeth using a double-sided carborundum disc and straight micromotor handpiece. Using carborundum paper, the discs were polished and washed with distilled water. The discs were etched using 37% phosphoric acid to remove any smear layer that was caused by the grinding process and to simulate dentinal hypersensitivity by opening the dentinal tubules. The specimens were again washed and stored in distilled water until use. Samples were then randomly allocated into Group A: calcium sodium phosphosilicate mouthwash, Group B: potassium nitrate mouthwash, and Group C: dipotassium oxalate monohydrate mouthwash. The specimens were immersed in a test tube filled with the respective mouthwash and vigorously shaken for 60 s for simulating the natural mouth rinsing action. This procedure was repeated for 7 days, twice daily. To compare and assess the proportion of dentinal tubule occlusion, all the samples were processed and examined under an SEM. Results: The efficacy of the mouthwash on the obliteration of dentinal tubules was compared using the Kruskal–Walis analysis of variance test followed by the post hoc Mann–Whitney U test for pairwise comparison. Group A showed completely occluded tubules in 5 (55.6) and mostly occluded tubules in 4 (44.4). Group B showed mostly occluded in 4 samples (44.4) and partially occluded in 5 samples (55.6) and Group C showed completely occluded tubules in 3 samples (33.3) and mostly occluded tubules in 6 samples (66.7). A P value of 0.05 or less is regarded as statistically significant. *P ≤ 0.05 is statistically significant. Between Group A and Group B as well as between Group B and Group C, there was a statistically significant difference. However, a statistically significant difference between Group A and Group C does not exist. Conclusion: The calcium sodium phosphosilicate group was shown to have the most occlusion of the dentinal tubule, followed by dipotassium oxalate monohydrate and potassium nitrate group.
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Guo, Linhai, Lingxue Meng, Chunlei Li, Hangyu Yue, Hui Wang, and Li Tian. "Growth of Diamond on Si, SiC, Mo and Diamond Substrates for Heat Spreader, Optical Window, and Surface Graphitized Devices." ECS Meeting Abstracts MA2024-02, no. 33 (2024): 4908. https://doi.org/10.1149/ma2024-02334908mtgabs.
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Introduction Diamond, owing to its exceptional impact resistance, high thermal conductivity, broad-spectrum optical transparency, elevated breakdown field strength, and superior carrier mobility, finds widespread application in diverse fields such as high-power laser windows, efficient heat spreader, and high-performance semiconductor devices. Experimental 1. Heteroepitaxial Growth of Polycrystalline Diamond on Si, SiC, and Mo Substrates: In this part, substrates employed include double-side polished 4H-polytype SiC, (100) single-side polished single-crystal Si wafers, and Mo substrates. Ultrasonic grinding of substrates using diamond powder ethanol suspension to promote the dispersion of nucleation seeds, followed by sequential ultrasonic cleaning in acetone, ethanol, and deionized water. Subsequently, MPCVD was used for diamond growth, using hydrogen, methane, oxygen, and a mixture of hydrogen and nitrogen as reaction gases. Using different processes to produce efficient heat sinks and high-power laser windows. 2. Homoepitaxial Growth of Single-Crystal Diamond on Diamond Substrates: In the homoepitaxial growth process, (100) double-side polished single-crystal diamond substrates are utilized. No need for ultrasonic grinding steps, cleaning steps are the same as above. Then use MPCVD for homogeneous epitaxial growth of single-crystal diamond. 3. Investigation of Graphitized Surface Devices on Diamond: This study also investigated the graphitization devices on diamond surfaces. A high-temperature metal-catalyzed method is employed to promote surface graphitization of diamond. Firstly, polish and clean the diamond. Subsequently, a 300 nm thick nickel layer is deposited on the diamond surface. Rapid thermal annealing is then performed at 1300°C to form a highly conductive graphite layer. This process successfully prepares capacitor samples with a graphite-diamond-graphite three-layer structure. Results and Discussion 1. High-Power Laser Window Plates: The fabricated laser window plates utilize Si, SiC and Mo substrates, employing an ultra-low nitrogen growth process with a growth rate of approximately 3.7 µm/h. After double-sided polishing, the thickness reaches 1 mm. At room temperature, the transmittance at 10.6 µm wavelength approaches the theoretical maximum, reaching 67.9%. The overall thermal conductivity exceeds 1950 W/mK, approximating that of single-crystal diamond. Raman spectroscopy and XRD results indicate that the primary component is polycrystalline diamond with a (110) crystallographic orientation. Laser testing results demonstrate that these window plates possess a high laser-induced damage threshold with a peak energy of 60 J/cm2 and a peak power of 12 MW/mm2, capable of withstanding high-power CO2 laser output. 2. Heat Spreader: This study involves depositing diamond on Si and SiC substrates, forming diamond-based composite materials. This significantly improves the heat dissipation efficiency of the devices, bringing their performance closer to theoretical limits. The deposition process employs a low-nitrogen technique to balance growth rate and defect density, achieving a growth rate of approximately 5 µm/h. Raman spectroscopy and XRD results indicate that the primary component is polycrystalline diamond with a (110) crystallographic orientation. Although the increased nitrogen content results in lower optical transmittance compared to optical window plates, the grain size can be increased from 124 nm to 22 μm through production process adjustments, thereby enhancing thermal conductivity. Test results demonstrate that the thermal conductivity of the Si-diamond composite material reaches 450 W/mK,3 times that of single-crystal Si. The SiC-diamond composite material achieves a thermal conductivity of 500 W/mK,3.5 times that of SiC. 3. Single-Crystal Diamond: The transmittance and thermal conductivity of single-crystal diamond grown by homoepitaxial growth are superior to those of polycrystalline diamond. However, limitations in size and growth conditions restrict its large-scale application in heat spreaders and optical windows. Single-crystal diamond is more suitable for manufacturing semiconductor devices such as diamond capacitors, Schottky diodes, and hydrogen-terminated MOSFETs. The author has conducted research on doping of single-crystal diamond. Characterization through Raman spectroscopy, XRD, and TEM confirms that the primary component is single-crystal diamond with a (100) crystallographic orientation. The dislocation density is below 103/cm2, meeting the stringent requirements for semiconductor devices. 4. Graphite-Diamond-Graphite Capacitors: Utilizing prepared diamond, graphite-diamond-graphite capacitors were fabricated. Measurements using a semiconductor parameter analyzer revealed a high capacitance value of 4 nF. TCAD simulation indicated a breakdown voltage as high as 1100 V. This research explores a novel method for diamond capacitor fabrication. Conclusions Diamond heteroepitaxial grown on Si, SiC, and Mo substrates has prepared high-power laser windows with 67.9% optical transmittance at 10.6 μm wavelength, and composite materials with thermal conductivity enhanced to 3-3.5 times that of the original materials. Homoepitaxially grown diamond on single-crystal diamond substrates exhibits a dislocation density below 10³/cm², meeting the requirements for semiconductor device substrates. Furthermore, this research has developed a novel diamond capacitor fabrication technique, yielding capacitors with a capacitance of 4 nF and a breakdown voltage of 1100 V.
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Khramcov, M. V., N. M. Chairkina, E. N. Dubovtseva, and S. A. Myznikov. "Stone-tool assemblage of the Eneolithic settlement of Tolum-1 in the Konda River Basin." VESTNIK ARHEOLOGII, ANTROPOLOGII I ETNOGRAFII, no. 3(62) (September 15, 2023): 14–25. http://dx.doi.org/10.20874/2071-0437-2023-62-3-2.
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In 2020, the expedition of Poengurr and the Institute of History and Archaeology of the Ural Branch of RAS investigated the settlement of Tolum-1, which functioned during the Neolithic, Eneolithic, Bronze and Early Iron Ages. The site is located in the north of Western Siberia, in Kondinsky District of Khanty-Mansi Autonomous Ok-rug — Yugra. Structure (dwelling) No. 3 containing a complex of stone tools and pottery of the Enyi type, as well as the adjoint area, were investigated by an excavation trench of an area of 499 m2. On the settlement, 108 stone items were found, the large part of which concentrates within the boundaries of dwelling No. 3. The research is based upon the method of technical and typological analysis of stone-tool assemblage, implying the development of a typology of stone tools and the study of their production technology taking into account the quality of the or-namental raw materials used by the ancient population. According to the raw-material composition of the stone-tool assemblage, mainly represented by soft rocks (grey-green slate, burgundy schist, etc.) and, to a lesser ex-tent, by flint of various colors, quartz and quartzite, the ancient population of this region did not have continuous sources of high-quality ornamental raw materials. Prevailing on the settlement are the tools for woodworking (drillbit-shaped tools, adzes, chisels), and also found were knives and a representative collection of arrowheads. Items for stone processing are few: a hammer-stone, a retoucher, and two cores. There is a higher presence of unprocessed pebbles and tiles, and chips and fragments of polished products. The main technological chain on the site was production of polished tools from local gray-green slate by chipping off and subsequent grinding. The production of flint tools by splitting and retouching was insignificant. The stone assemblage of the Tolum-1 settle-ment finds analogies in the complexes of the Enyi type of the north of Western Siberia. Certain categories and types of products are more widespread — double-sided retouched fish-shaped arrowheads are found in quantity in the Trans-Urals, polished leaf-shaped arrowheads with a groove — in the Eneolithic sites of the north of Wes-tern Siberia, while polished arrowheads with a tapered truncated base were found among the Eneolithic materials of the Surgut Ob Basin and on the sites with the Ushya ceramics of the Neolithic Period of the Konda lowland. Polished rounded and teardrop-shaped pendants are found in the funerary and, to a lesser extent, settlement complexes of the Trans-Urals and Western Siberia in the Late Neolithic — Eneolithic. A series of radiocarbon dates obtained for the settlement of Tolum-1 and other sites of the Enyi type in the north of Western Siberia, as well as the technical and technological characteristics and morphology of the stone inventory of the settlement under consideration, and a wide range of analogies leave open the possibility of attributing the structure No. 3 to the Eneolithic Period, within the span of the calibrated dates in the interval of 3600–2600 BC.
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Li, Qingliang, Gensheng Zhang, Shichao Xiu, Xiannan Zou, and Yingbo Zhao. "Analysis of grinding fluid efficiency in double-sided grinding." International Journal of Advanced Manufacturing Technology, August 22, 2023. http://dx.doi.org/10.1007/s00170-023-12125-2.
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Никитина, И., I. Nikitina, А. Поляков, and A. Polyakov. "EXPERIMENTAL INVESTIGATION OF THE TEMPERATURE AND ACCURACY CHARACTERISTICS OF DOUBLE-SIDED FACE GRINDING MACHINE." Bulletin of Belgorod State Technological University named after. V. G. Shukhov, November 20, 2019, 112–20. http://dx.doi.org/10.34031/2071-7318-2019-4-11-112-120.
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The paper proposes a methodology for experimental studies of double-sided face grinding machines on the criterion of heat resistance, including: method of simulating a grinding process; measurement of temperature; measurement of changes in relative angular position of the circles; the measurement of processing errors. The proposed methods for experimental studies of the thermal behavior and errors in the machining of a double-sided face grinder allow for fine-tuning of the machine under production conditions. At the same time, preliminary tests of a double-sided face grinder show that when grinding an industrial batch of cylindrical rollers, excessive temperatures are distributed unevenly across the machine nodes both at idle and during grinding. The ends of the spindle heads and the stand have the greatest excess temperature when working at idle, and when grinding - on the surface of the machine, located in close proximity to the grinding zone. The nature of changes in excess temperatures of characteristic points and coolant when simulating the grinding process on the machine completely coincided with the experimental data obtained on a working machine.
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"Double-sided deep grinding of gas turbine engine blades with highly porous CBN tool." Vestnik Mashinostroeniya, October 2023, 812–17. http://dx.doi.org/10.36652/0042-4633-2023-102-10-812-817.
Full textAbstract:
The results of the implementation of high-porous cubic boron nitride (CBN) grinding wheels in the operation of double-sided deep grinding of the fir-tree profile of the locking element of the turbine blade are presented. The features of designing the working layer of the CBN wheel for this operation are described. Recommendations for the selection of the characteristics of diamond dressing rollers are formulated. The principles of organizing an efficient production process when introducing CBN grinding wheels are described. Keywords: deep grinding, part, gas turbine engine, working turbine blade, grinding wheel dressing, diamond profile roller, highly-porous CBN grinding wheels. d_i_volkov@rsatu.ru, boris_tsvetkov@mail.ru
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Zhang, Chao, Xian Wu, Hongfei Yao, et al. "Experimental research on the double-sided grinding of PCBN materials with different microstructures." International Journal of Refractory Metals and Hard Materials, February 2025, 107126. https://doi.org/10.1016/j.ijrmhm.2025.107126.
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Yang, Yongming, Zhonghou Wang, Lei Liu, Zhaoyao Shi, and Aizoh Kubo. "Influence of Topological Modification in Double-Sided Grinding by Forming Method Based-On the Angle Error of Intersecting Shaft on Gear Transmission." SSRN Electronic Journal, 2022. http://dx.doi.org/10.2139/ssrn.4024109.
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