scholarly journals Use of the toolholder with the oriented stiffness for ultrasonic turning

2021 ◽  
Author(s):  
Oleksandr Shevchenko ◽  
Serhiy Manzyuk
Keyword(s):  
Cutting Force ◽  
Experimental Studies ◽  
Ultrasonic Vibrations ◽  
New Device ◽  
Increase Productivity ◽  
Ultrasonic Cutting ◽  
Elastic Elements

An effective way of processing difficult-to-machine materials is ultrasonic cutting, which is carried out by applying ultrasonic vibrations to the movement of the cutter and contributes to a significant reduction in cutting force and increase processing productivity. The article presents the results of research on the efficiency of using a new device for ultrasonic cutting with an electrostrictive vibrating drive. The source of ultrasonic vibrations is an electrostrictive vibratory drive, which provides oscillations in the range of 10 - 20 kHz with amplitude of 10 - 15 microns. Experimental studies have confirmed the effectiveness of the proposed design of the toolholder to transmit the wave of ultrasonic vibrations almost perpendicular to the axis of the vibratory drive, which allows you to unload the vibrating drive from the cutting force and use vibration pulses only to deform elastic elements by the amplitude of ultrasonic vibrations. The device provides conditions for processing of difficult-to-process materials, allows increasing accuracy of processing of details, to reduce roughness of the processed surfaces and to increase productivity of processing.

Воздействиеультразвуковогополянадинамическуювязкостьводы

2019 ◽  
pp. 27-29
Author(s):  
P. Vikulin ◽  
K. Khlopov ◽  
M. Cherkashin
Keyword(s):  
Dynamic Viscosity ◽  
Experimental Studies ◽  
Ultrasonic Field ◽  
Maximum Effect ◽  
Ultrasonic Frequency ◽  
Ultrasonic Vibrations ◽  
Wastewater Disposal ◽  
Laboratory Setup ◽  
Sonic Treatment ◽  
The Impact

Enhancing water purification processes is provided by various methods including physical ones, in particular, exposure to ultrasonic vibrations. The change in the dynamic viscosity of water affects the rate of deposition of particles in the aquatic environment which can be used in natural and wastewater treatment. At the Department Water Supply and Wastewater Disposal of the National Research Moscow State University of Civil Engineering experimental studies were conducted under laboratory conditions to study the effect of ultrasound on the change in the dynamic viscosity of water. A laboratory setup has been designed consisting of an ultrasonic frequency generator of the relative intensity, a transducer (concentrator) that transmits ultrasonic vibrations to the source water, and sonic treatment tanks. Experimental studies on the impact of the ultrasonic field in the cavitation mode on the dynamic viscosity of the aqueous medium were carried out the exposure time was obtained to achieve the maximum effect.Интенсификация процессов очистки воды осуществляется с помощью различных методов, в том числе и физических, в частности воздействием ультразвуковых колебаний. Изменение динамической вязкости воды влияет на скорость осаждения частиц в водной среде, что может быть использовано в процессах очистки природных и сточных вод. На кафедре Водоснабжение и водоотведение Национального исследовательского Московского государственного строительного университета в лабораторных условиях проведены экспериментальные исследования по изучению влияния ультразвука на изменение динамической вязкости воды. Разработана схема лабораторной установки, состоящая из генератора ультразвуковых частот с соответствующей интенсивностью, преобразователя (концентратора), передающего ультразвуковые колебания в исходную воду, и емкости для озвучивания. Выполнены экспериментальные исследования по влиянию ультразвукового поля в режиме кавитации на динамическую вязкость водной среды, получено время экспозиции для достижения максимального эффекта.

scholarly journals Experimental Evaluation of Airlift Performance for Vertical Pumping of Water in Underground Mines

2021 ◽  
Author(s):  
Parviz Enany ◽  
Oleksandr Shevchenko ◽  
Carsten Drebenstedt
Keyword(s):  
Water Flow ◽  
High Efficiency ◽  
Experimental Studies ◽  
Theoretical Models ◽  
Injection System ◽  
Experimental Investigations ◽  
Flow Mode ◽  
New Device ◽  
Riser Pipe ◽  
Airlift Pump

AbstractThis paper presents experimental studies on the optimization of air–water flow in an airlift pump. Airlift pumps use compressed gas to verticall transport liquids and slurries. Due to the lack of theoretical equations for designing and predicting flow regimes, experimental investigations must be carried out to find the best condition to operate an airlift pump at high efficiency. We used a new air injection system and different submergence ratios to evaluate the output of a simple pump for vertical displacement of water in an underground mine. The tests were carried out in a new device with 5.64 m height and 10.2 cm circular riser pipe. Three air-jacket pipes, at different gas flows in the range of 0.002–0.09 m3/s were investigated with eight submergence ratios. It was found that with the same air flow rate, the most efficient flow of water was achieved when an air jacket with 3 mm diameter holes was used with a submergence ratio between 0.6 and 0.75. In addition, a comparison of practical results with two theoretical models proposed by other investigators showed that neither was able to accurately predict airlift performance in air–water flow mode.

Experimental study and multi-objective optimization of process parameters during turning of 100Cr6 using C-type advanced coated tools

2021 ◽  
pp. 095440622110431
Author(s):  
LR Bhandarkar ◽  
PP Mohanty ◽  
SK Sarangi
Keyword(s):  
Cutting Force ◽  
Distance Measure ◽  
Experimental Studies ◽  
Cutting Speed ◽  
Bearing Steel ◽  
Depth Of Cut ◽  
X Ray ◽  
Coated Tools ◽  
Reduction Coefficient ◽  
Machining Parameter

The drive of this research is to examine the machinability of 100Cr6 bearing steel using advanced C-type cutting tools. Experimental studies investigated the effects of machining variables on the surface quality, chip reduction coefficient and cutting force. Seven advanced coated tools were checked for characterization by micro hardness (VHN), adhesion quality, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS). The experimental trials were planned by Taguchi’s L18 orthogonal array using a mixed-level design. Two numerical machining variables feed rate and cutting speed, and one categorical machining variable tool type was taken into consideration while a constant depth of cut was kept for all trails. A combined Taguchi-Satisfaction function distance measure approach was implemented for multi-response optimization. The most promising machining parameter setting for minimization of surface roughness, cutting force, and chip reduction coefficient was identified. The most important process parameter was found to be tool-type. Ceramics tools are found to be best trailed by WC coated tools under most of the conditions. Lower tool wear was observed in the CBN tool as compared to others.

Ultrasonic Cutting of Switchgrass and Miscanthus Stems

2018 ◽  
Vol 34 (2) ◽  
pp. 343-353
Author(s):  
A. Bulent Koc Koc ◽  
Bo Liu
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Frequency ◽  
Cutting Speed ◽  
Particle Size Reduction ◽  
Element Analysis ◽  
Cutting Energy ◽  
High Frequency Vibrations ◽  
Ultrasound Assisted ◽  
Ultrasonic Cutting

Abstract. Ultrasound-assisted cutting has been used to cut materials with high precision, improved quality and reduced cutting forces. The research objective was to investigate the effects of high-frequency vibrations on the cutting force and cutting energy of switchgrass and miscanthus stems. Laboratory experiments were conducted on individual biomass stems at cutting speeds between 3 and 400 mm/s. An experimental cutting system with an ultrasound generator, an ultrasonic blade, a load cell, and a data acquisition system was developed. The custom designed blade was 5-cm wide and vibrated at 19.551 kHz with 2.8 µm tip vibration amplitude. There were significant measured differences in the cutting forces and cutting energies between conventional cutting and ultrasonic cutting of switchgrass and miscanthus stems (p < 0.05). These results suggest that the use of high-frequency vibrations reduce cutting force and cutting energy of both switchgrass and miscanthus stems. Ultrasound-assisted cutting reduced the cutting energy of switchgrass by 66.85% at 100 mm/s and miscanthus by 80.58% at 30 mm/s. However, ultrasonic cutting did not have a significant effect on the cutting force and cutting energy when the cutting speed was equal to or greater than the blade tip vibration speed. The results of this research should be useful for adapting the ultrasonic technology in biomass harvesting, particle size reduction, and processing equipment. Keywords: Biomass, Blades, Energy, Finite element analysis, Miscanthus, Switchgrass, Ultrasonics.

scholarly journals The mathematical models for cutting force calculation during structural and corrosion-resistant steels` parts processing

2019 ◽  
Vol 298 ◽  
pp. 00099
Author(s):  
Alexey A. Zhdanov ◽  
Oleg A. Kursin ◽  
Pham Xuan Bach
Keyword(s):  
Mathematical Models ◽  
Cutting Force ◽  
Experimental Studies ◽  
Additional Parameter ◽  
Corrosion Resistant ◽  
Cutting Force Components ◽  
Force Components ◽  
Quantitative Indicators ◽  
Force Calculation ◽  
Thermo Physical Properties

The paper shows that conventional mathematical models for calculating the cutting force components during the turning process, represented in reference guides on engineering, give drastic errors reaching 100 percent or more for various tool-workpiece couples. These errors interfere with applying reference values of the cutting force for any further calculations, equipment selection, workpiece positioning scheme, workpiece deformation value due to the elastic of the technological system elements during processing and etc., because of the insufficient reliability of the results of such calculations. The paper proposes mathematical models obtained as a result of experimental studies, which allow for increasing the accuracy of the calculation of the components of the cutting force by introducing an additional parameter – i.e., the value of thermo EMF of the test running into the calculation formulas. This approach enables to reduce the error in the calculation of the components of the cutting force up to ± 15%. In addition, the need for the development of specific mathematical models for various groups of materials machined is shown, which is due to the peculiarities of contact processes in the machining of various groups of steels, as well as to qualitative and quantitative indicators of the thermo-physical properties of the materials of tool-workpiece contact couples.

Development of the Two-Dimensional Ultrasonic Cutting System Based on the Mechanism of Single-Excitation Elliptical Vibration by Means of Opening Chutes on the Horn

2016 ◽  
Vol 693 ◽  
pp. 1272-1278
Author(s):  
Jie Li ◽  
Feng Jiao ◽  
Ying Niu ◽  
Long Fei Shi
Keyword(s):  
Cutting Force ◽  
Ultrasonic Vibration ◽  
Two Dimensional ◽  
Vibration Cutting ◽  
Elliptical Vibration ◽  
Cutting Experiments ◽  
Cutting System ◽  
Ultrasonic Vibration Cutting ◽  
Ultrasonic Cutting ◽  
Force Characteristics

Based on the mechanism of single-excitation elliptical vibration by means of opening chutes on the horn, a novel two-dimensional ultrasonic cutting system was developed. Vibration characteristics of the two-dimensional ultrasound cutting system were researched and the longitudinal and bending amplitude of the system with different number of chutes were obtained. By using developed two-dimensional ultrasonic vibration cutting systems, series of cutting experiments were carried out and cutting force characteristics were researched compared with that in traditional cutting.

scholarly journals A device for reducing the siltation of the front chamber of the pumping station in irrigation systems

2021 ◽  
Vol 274 ◽  
pp. 03001
Author(s):  
Boborakhim Urishev ◽  
Sobir Eshev ◽  
Fakhriddin Nosirov ◽  
Ulugbek Kuvatov
Keyword(s):  
Hydraulic Structure ◽  
Experimental Studies ◽  
Calculated Data ◽  
Bottom Layer ◽  
Design Parameters ◽  
Pipeline System ◽  
New Device ◽  
Water Jets ◽  
Pumping Stations ◽  
Calculation Methodology

It has been determined that the reduction of siltation of the front chamber is necessary because the deposited sediments seriously violate the planned hydraulic structure of the flow when water is sucked up by pumps, as a result of which their efficiency decreases. The method of calculating the pipeline system of a new device designed to significantly reduce the siltation of the front chamber of irrigation pumping stations by artificially creating turbulence in the water flow in the bottom layer of the structure is presented. This calculation methodology is based on the use of the theory of flooded water jets, which makes it possible to determine the main characteristics of the jet. The latter allows calculating the design parameters of the pipeline system. The results of experimental studies are presented to compare the calculated data with the results of experiments, as well as to determine the effectiveness of the proposed device for a significant reduction in siltation of the front chamber of irrigation pumping stations.

scholarly journals Manufacturing Parts for Hydraulic Systems of Agricultural Machinery under Conditions of Ultrasonic Cutting

2020 ◽  
Vol 30 (4) ◽  
pp. 624-636
Author(s):  
Vladimir A. Skryabin
Keyword(s):  
Cutting Force ◽  
Cutting Speed ◽  
Special Device ◽  
Hydraulic Systems ◽  
Agricultural Machinery ◽  
Part Surface ◽  
Processing Accuracy ◽  
Thin Walled ◽  
Ultrasonic Cutting

Introduction. The article deals with the problem of reducing the efforts when processing thin-walled bushings for hydraulic systems of agricultural machines with the ultrasonically activated cutting tool to achieve the specified processing accuracy and surface roughness of parts. Materials and Methods. The article describes the technological standards for ultrasonic cutting. To assess the change in the tangential cutting force, a special device was developed to activate ultrasonically the tool for tangential cutting and corresponding experiments were carried out. Results. An upgrading of a screw-cutting lathe equipped with a special device for ultrasonic cutting of low rigidity thin-walled parts is currently being carried out. The upgraded lathe consists of blocks for processing and measuring experimental research data connected to a personal computer. The upgraded lathe allows evaluating the change in cutting forces under traditional turning and ultrasonic cutting to achieve the specified accuracy and roughness of the part surface during the processing process. Discussion and Сonclusion. Processing low rigidity parts on the modernized equipment has shown that providing the effective conditions of manufacturing thin-walled bushings for agricultural machinery (cutting depth and cutting speed) decreases radial and tangential components of the cutting force that helped to reduce the energy consumption of the cutting process and to stabilize quality of the processing.

scholarly journals Cutting Force Prediction and Experiment Verification of Paper Honeycomb Materials by Ultrasonic Vibration-Assisted Machining

2020 ◽  
Vol 10 (13) ◽  
pp. 4676 ◽  
Author(s):  
Wenjun Cao ◽  
Jun Zha ◽  
Yaolong Chen
Keyword(s):  
Finite Element ◽  
Cutting Force ◽  
Ultrasonic Vibration ◽  
Core Material ◽  
Disc Cutter ◽  
Honeycomb Core ◽  
Cutting Force Prediction ◽  
Paper Honeycomb ◽  
Ultrasonic Cutting ◽  
Core Materials

The disc-cutter is a finishing tool for the ultrasonic-cutting of paper honeycomb-core material. The cutting state directly affects the machining accuracy and surface quality of the workpiece. The cutting force is an important physical quantity and the cause of ultrasonic cutting defects of the honeycomb-core material. Due to differences in the mechanical properties and cutting performance of honeycomb-core materials and commonly used metal materials, existing metal-cutting-force models cannot be applied to the calculation of ultrasonic cutting forces in the processing of honeycomb-core materials. In response to this problem—combined with actual working conditions using the ABAQUS finite element analysis software—a finite element simulation model of the ultrasonic vibration-assisted cutting force of the disc-cutter on the honeycomb-core material was established, and the cutting curves and values were obtained. The experiment of ultrasonic vibration cutting of the disc-cutter proves that from the surface morphology of the honeycomb core, the milling-width has the greatest influence on the cutting force, and the cutting-depth has the smallest influence on the cutting force. The maximum error between the cutting force experimental results and the finite element simulation results under the same cutting conditions was 13.2%, which means that the established cutting-force finite element model is more accurate and can be used to predict the cutting in honeycomb ultrasonic vibration-assisted cutting-force value. Finally, based on the response surface method, a three-dimensional cutting force prediction model of the ultrasonic cutting honeycomb core of the disc-cutter was established by using the simulation model data. The results of this study can provide a useful basis for the improvement of cutting performance and processing efficiency in the processing of paper honeycomb-core materials.

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