scholarly journals Technological prerequisites for the energy efficiency increase of the engine cylinder bore processing

2021 ◽  
Vol 279 ◽  
pp. 01001
Author(s):  
Lydmila Safarova ◽  
Andrey Malikov ◽  
Alexandr Yamnikov ◽  
Olga Yamnikova

An example of the rationalization of the current technology for manufacturing a cylinder of a small-sized diesel engine at PA “TULAMASHZAVOD” from a cast iron is given. It is shown that lowpower obsolete equipment leads to an increase in the number of technological operations and equipment used. However, even if all the generally accepted technological recommendations are followed, only 80% of the parts meet the requirements for the required parameters of accuracy and quality of the cylinder bore surface. Studies have found that the main reasons for insufficient quality are the presence of residual stresses in the casting, which cannot be removed during artificial aging, as well as insufficient accuracy and rigidity of metal cutting equipment at turning and boring operations. The use of more powerful and accurate modern equipment is theoretically and experimentally justified, which, due to increased refinement, allows reducing the number of machining operations. Replacement of artificial thermal aging by natural, combined with the replacement of shaft furnaces for heat treatment of workpieces with chamber furnaces of lower power and higher capacity, reduce energy consumption for the manufacturing by almost 4 times.

2020 ◽  
Vol 854 ◽  
pp. 64-73
Author(s):  
Ilya V. Gorshkov ◽  
M.A. Popov

Modern methods of machining of bed slideways with the required parameters of accuracy and quality of the processed surfaces are considered in order to increase productivity in the treatment of the surface of machine stands. To improve productivity, the finishing sanding operation has been replaced with finishing milling to ensure the required roughness, flatness and parallelism. The method of replacement of technological operations as exemplified by processing of a bed made of gray cast iron of grade “СЧ-20” is studied. The priority method of increasing the productivity of the processing of machine slideways of metal-cutting equipment, based on the use of cutting ceramics during the processing of the bed as a final technological operation, is determined. Based on the microstructural characteristics of oxide-carbide cutting ceramics, a uniform method of equipping cutters with cutting inserts with equal lifespan is used to increase productivity and achieve the required surface finish. This method of the milling cutter layout allows for longer life and provides the required margin of tool accuracy as well as allows predicting premature wear of the cutting tool. The results of the work are the identification of the patterns of influence of structural parameters of cutting ceramics on the quality of machine slideways of metal-cutting equipment in the selective formation of instrumentation. Studies have shown that the quality of machining depends on the microstructure characteristics of each insert used in the machining process when using interchangeable multi-sided oxide carbide ceramic inserts. The increase in productivity and quality of machining is achieved by monitoring the microstructure of the cutting oxide-carbide ceramics.


2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Xueping Zhang ◽  
Zaoyang Zhou ◽  
Zhenqiang Yao ◽  
Lifeng Xi

Abstract The dimensional accuracy of engine cylinder bore at multiscale has a tremendous influence on engine performances including friction power loss, vibration, leak tightness between piston and cylinder, and wear resistance. Tremendous researches were devoted to predict the dimensional accuracies of the honed cylinder by means of analytical, experimental, and numerical simulation methods. The dimensional quality of the honed cylinder bore was usually determined by establishing the relationship between honing parameters and dimensional accuracies of the honed cylinder bore. However, most researches predicted dimensional accuracy at macroscale or surface texture at microscale, respectively. Few efforts were devoted to predict the dimensional quality of honed cylinder bore at both macroscale and microscale levels simultaneously. To explore a new understanding of the honing mechanism of the cylinder bore, a multiscale model is proposed to predict the dimensional accuracy and surface texture of cylinder bore generated from the honing process at the macroscale and microscale simultaneously. The model aims to integrate both microscale factors including honing stone abrasives distribution, abrasive wear process, previous cylinder surface topography, and macroscale factors including cylinder geometric features and honing head motion trajectory into a multiscale analytical analysis. A force matching method is adopted in the multiscale predictive model to determine the feed depth in the honing of the cylinder bore. Thus, the proposed multiscale analytical model possesses an excellent capacity to simultaneously predict the roundness and cylindricity of the honed cylinder bore, as well as the surface texture/roughness of the honed cylinder bore in terms of Abbott-Firestone curve. The simulated results also revealed that the material removal process is closely related to the initial shape deviations of the cylinder bore, which cannot be corrected, compensated, or eliminated by the subsequent honing process given the deviations are associated with wavelengths higher than 27 mm under the given honing condition.


2020 ◽  
Vol 25 (1) ◽  
pp. 82-86
Author(s):  
V.S. Antipenko ◽  
◽  
Yu.N. Kharitonov ◽  
N.S. Nikolaeva ◽  
◽  
...  

For the optimal choice of metal-cutting equipment for the production of parts of various industries, in particular metal-cutting machines, various studies, including marketing, are required. Improving the quality of manufactured products is achieved by creating and selecting size ranges (ranges) of metal-cutting equipment that fully satisfy current and future consumer demands. The total cost of ownership to optimize the selection of metal cutting equipment is an element of marketing research. Optimizing your total cost of ownership will help you make the right decision when purchasing equipment.


1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.


Author(s):  
M. Z. Haq ◽  
M. R. Mohiuddin

The paper presents a thermodynamic analysis of a single cylinder four-stroke spark-ignition (SI) engine fuelled by four fuels namely iso-octane, methane, methanol and hydrogen. In SI engines, due to phenomena like ignition delay and finite flame speed manifested by the fuels, the heat addition process is not instantaneous, and hence ‘Weibe function’ is used to address the realistic heat release scenario of the engine. Empirical correlations are used to predict the heat loss from the engine cylinder. Physical states and chemical properties of gaseous species present inside the cylinder are determined using first and second law of thermodynamics, chemical kinetics, JANAF thermodynamic data-base and NASA polynomials. The model is implemented in FORTRAN 95 using standard numerical routines and some simulation results are validated against data available in literature. The second law of thermodynamics is applied to estimate the change of exergy i.e. the work potential or quality of the in-cylinder mixture undergoing various phases to complete the cycle. Results indicate that, around 4 to 24% of exergy initially possessed by the in-cylinder mixture is reduced during combustion and about 26 to 42% is left unused and exhausted to the atmosphere.


Author(s):  
H.M. Magid

Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions. Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process. Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis. Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height. Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ). Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.


Author(s):  
Guicheng Wang ◽  
Chunyan Zhang ◽  
Hongjie Pei ◽  
Yunming Zhu ◽  
Chungen Shen ◽  
...  

The surface quality is always the crucial element of machined quality in precision ultra-precision metal cutting. A new concept that the surface integrity should include the edge quality of parts is put forward In this paper, the weight value of a series of characteristic parameters of surface integrity are calculated with using analytic hierarchy process, three basic methods of evaluating surface integrity are presented, and the comprehensive evaluation system has been formed which will theoretically play a great important role on rapid development in the precision machining.


2017 ◽  
Vol 2 (2) ◽  
pp. 3-8
Author(s):  
Ольга Медведева ◽  
Olga Medvedeva ◽  
Александр Янюшкин ◽  
Aleksandr Yanyushkin ◽  
Павел Архипов ◽  
...  

In the paper there are emphasized problems connected with the use of diamond metal bond abrasive discs at the processing of hard alloys. The reasons of cutting capacity decrease are pointed out which limit a wide-spread use of a diamond metal bond tool. It is established that for the achievement of a required productivity and quality of ready products is possible at the expense of the application of electro-chemical and electro-physical methods of stropping and also due to the improvement of abrasive disc designs. This work reports the investigations of a cutting capacity of diamond discs at the working of hard alloys by a combined method of electro-chemical grinding with simultaneous continuous stropping. As an output parameter there was accepted a cutting capacity factor of a diamond which was assesses according to the changes in effective working capacity. On the basis of the results of the experimental data processed there were obtained theoretical models of the dependence of the cutting capacity factor upon electric and mechanical constituents of the modes of combined electro-chemical grinding. A complex of investigations directed to the detection of efficient modes ensuring the stability of cutting capacity in diamond metal bond discs is carried out. It is experimentally confirmed that the application of the method of combined electro-chemical grinding with the simultaneous continuous disc stropping at working hard alloy materials allows increasing diamond disc cutting capacity by 15% in comparison with other methods of the diamond working of such materials.


2020 ◽  
Vol 6 (Extra-C) ◽  
pp. 320-325
Author(s):  
Elena V. Konvisarova ◽  
Tatiana A. Levchenko ◽  
Vadim V. Shcherbakov ◽  
Ilia S. Vzdorik ◽  
Maxim N. Kriuchkov

The purpose of the study is to determine the ways which intensify the investment activity of enterprises in the Russian Far East. They performed the comparative analysis of the rating methods used in the Russian Federation to assess the investment attractiveness of the regions. It was revealed that a common characteristic of the analyzed methods is to consider the infrastructural factor and their institutional environment, and, in particular, the presence and quality of the business support infrastructure. These factors directly affect the investment attractiveness of a single enterprise and project, as they form the investor's attitude. To increase the investment attractiveness of the Russian Far East regions, it is necessary to use the experience of the Asia-Pacific countries. The work formulated recommendations on the application of Chinese experience in relation to Russian territories with preferential economic regimes. To solve the problem of efficiency, increase and intensity the investment activities of enterprises, the concept of management. accounting tool application is proposed.    


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