scholarly journals The changes of the workpiece surfaces by hard machining by milling and burnishing

Mechanik ◽  
2018 ◽  
Vol 91 (8-9) ◽  
pp. 727-729
Author(s):  
Daniel Grochała ◽  
Emilia Bachtiak-Radka ◽  
Sara Dudzińska
Keyword(s):  
Time Use ◽  
Automotive Industry ◽  
High Hardness ◽  
The State ◽  
Functional Requirements ◽  
Technological Parameters ◽  
Shape Accuracy ◽  
Part Surface ◽  
The Impact

Today’s machines have to be characterized by increasingly better functional and operational properties. The devices should work faster, more efficiently with higher accelerations and at the same time use less energy than it was a few years ago. These requirements apply to the products from the automotive industry, aviation machine tools or machines serving people in everyday life to play or learn. At the same time, a guarantee of long and trouble-free operation is required. In connection with the above, it is increasingly difficult for the technologist to prepare parts that meet the very strict requirements of dimensional and shape accuracy and the state of the geometric structure of the surface (SGP). Also, more and more emphasis is placed on meeting the additional functional requirements of the part surface (hydrophobic or hydrophilic properties, the degree of isotropy or the ability to maintain coatings and lubricants). The paper presents the results of the work aimed at determining the effect of technological parameters of milling and burnishing when treating the surface of parts in the state improved by heat to high hardness. The work focused in particular on the determination of the impact of the strategy of the implemented treatment on changes in the value of SGP indices describing the load-bearing capacity of the surface.

scholarly journals The Contact Mechanics of Novikov’s Surface-Hardened Gearing during Running-in Process

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Alexey Beskopylny ◽  
Nikolay Onishkov ◽  
Viktor Korotkin
Keyword(s):  
Cold Deformation ◽  
Contact Fatigue ◽  
High Hardness ◽  
Contact Spot ◽  
The State ◽  
Contact Strength ◽  
Friction Forces ◽  
Contact Surfaces ◽  
Defective Surface ◽  
The Impact

The article is devoted to the analysis of the state of the contact surfaces of the higher kinematic pair in the general case of relative motion, that is, in the presence of rolling, sliding, and twisting, which is characteristic of Novikov’s circular-screw gears. The purpose of the work is to assess the impact of friction forces, the state of contact surfaces after tool processing, and the localization of the instantaneous contact spot on the level of contact—fatigue durability of gears. Power contact in the presence of geometric slippage of the mating surfaces leads to a significant change in the initial geometry and the mechanical properties of surface layers. In the existing methods of calculations of contact strength, the effect of running-in is investigated insufficiently, which leads to an incorrect result, especially for gear with high hardness of the teeth. In this work, the conditions of contact interaction close to the real requirements are studied on the basis of experimental material, numerical solution of the contact problem, determination of the terms of the contact areas of slip, and adhesion within the instantaneous spot. The shape of the instant contact spot has asymmetry and can be approximated by an ellipse with the introduction of a correction factor. The running-in period is of a plastic nature with cold deformation and reduction of the roughness of surfaces. As a result of the run-in period, the area of actual contact (tooth height) is increased by 2 or more times. It is not desirable to spread the area of contact at the area of adhesion that initiates the formation of pitting. The presence of defective surface area on the level of contact strength does not have significant influence, because of the running-in period, but increases the risk of spalling and brittle fracture.

Identification and Analysis of Residual Stresses in the Axisymmetric Workpiece Existing before and after Machining

2016 ◽  
Vol 686 ◽  
pp. 33-38 ◽  
Author(s):  
Tadeusz Otko ◽  
Wojciech Zębala
Keyword(s):  
Point Of View ◽  
Internal Stresses ◽  
Entire Volume ◽  
Shape Accuracy ◽  
Workpiece Surface ◽  
Plastic Processing ◽  
Machining Allowance ◽  
Before And After ◽  
The Impact

Semi-manufactured parts dedicated for precise machining often have internal stresses which have remained after previous cutting and plastic processing. These stresses reside in a fixed state of balance over the entire volume of the workpiece. Removal of the machining allowance is associated with a change in the state of balance and deformation of the workpiece, which affect its dimensional and shape accuracy. The study, involving non-stress removal of precisely defined volume of the machining allowance and determination of the impact of this treatment on the deformation of the workpiece surface is presented. It is important from the point of view of dimensional tolerance of the axially symmetrical workpiece, finally processed by turning.

scholarly journals The Impact Of Surface Shape Of Chip-Breaker On Machined Surface

2015 ◽  
Vol 12 (2) ◽  
pp. 24-27
Author(s):  
Michal Šajgalík ◽  
Andrej Czán ◽  
Juraj Martinček ◽  
Daniel Varga ◽  
Pavel Hemžský ◽  
...  
Keyword(s):  
Automotive Industry ◽  
Cutting Tools ◽  
Cutting Parameters ◽  
Surface Shape ◽  
Technological Parameters ◽  
Machined Surface ◽  
Chip Breaker ◽  
Cutting Insert ◽  
Chip Size ◽  
The Impact

Abstract Machined surface is one of the most used indicators of workpiece quality. But machined surface is influenced by several factors such as cutting parameters, cutting material, shape of cutting tool or cutting insert, micro-structure of machined material and other known as technological parameters. By improving of these parameters, we can improve machined surface. In the machining, there is important to identify the characteristics of main product of these processes – workpiece, but also the byproduct - the chip. Size and shape of chip has impact on lifetime of cutting tools and its inappropriate form can influence the machine functionality and lifetime, too. This article deals with elimination of long chip created when machining of shaft in automotive industry and with impact of shape of chip-breaker on shape of chip in various cutting conditions based on production requirements.

scholarly journals Increasing The Efficiency Of Thermal Processing Under The Influence Of Magnetic Fields

2020 ◽  
Vol 02 (11) ◽  
pp. 428-434
Author(s):  
Umidjon Kasimov ◽  
◽  
Zulfiyaxon Mamataliyeva ◽  
Keyword(s):  
Thermal Treatment ◽  
Magnetic Fields ◽  
Impact Toughness ◽  
Thermal Processing ◽  
Impact Resistance ◽  
Vertical Direction ◽  
Technological Parameters ◽  
The Impact

In this article it is proposed to increase the impact resistance of alloyed stamped steels during magneto thermal treatment without changing the hardness. Determination of the optimal technological parameters for magneto thermal treatment of steels 5ХНМ, ЗХЗМЗФ, 4Х5МФС, 4Х5В2ФС. It is recommended to increase the impact toughness when processing steel 4X5В2ФС with a cyclic magnet in the vertical direction of the samples during magneto thermal treatment.

scholarly journals Influence of the margin of error due to the use of aerial photographs on the interpretation of the shoreline changes: Three cases of study (Atlantic coast of Morocco)

2020 ◽  
Author(s):  
Khalid El KHALID ◽  
Mehdi Maanan ◽  
Mounir Hakkou ◽  
Bendahhou Zourarah
Keyword(s):  
Atlantic Coast ◽  
The State ◽  
Decision Makers ◽  
Aerial Photographs ◽  
Shoreline Changes ◽  
Margin Of Error ◽  
The Impact

Abstract In mesotidal environments, the monitoring of shoreline changes is hampered by the determination of this line on aerial photographs. This paper discusses and evaluates the importance of taking into account the margin of error associated in determining the state of the shoreline. To demonstrate this effect, three cases were selected and studied using aerial photographs from 1946 and 2016 (70-year period). The sites chosen on the Moroccan Atantic coast are very close to each other but evolve differently. We proved statically that the impact of taking into account the margin of error will not have the same effect on the interpretation of the results. By taking these errors into consideration, the interpretation of the results becomes more consistent and more suitable for the decision-makers.

scholarly journals HYGIENIC REGULATION FOR JOINTLY ACTING HARMFUL FACTORS AND METHODOLOGY OF ITS EXPERIMENTAL RATIONALE

2020 ◽  
Vol 99 (2) ◽  
pp. 217-221
Author(s):  
Yury N. Katulskiy
Keyword(s):  
Toxic Effect ◽  
The State ◽  
The Body ◽  
Regression Equations ◽  
Experimental Animals ◽  
Cooperative Agents ◽  
Combined Action ◽  
Exposure Levels ◽  
The Impact

With the combined action of agents, the toxic effect depends not only on the time and effects levels of each of them but also on the combinations in which these levels are located. The main problems in the experimental substantiation of hygienic regulations for this type of action are the determination of this dependence, the establishment with its help of safe combinations of exposure levels and their description. In the work methods of their solution are offered. This dependence is recommended to be obtained in the economical experiments proposed by the theory of mathematical planning. It is represented by a system of regression equations describing the dose dependencies observed at different moments after the onset of the impact (when indices are removed). In this case, the toxic effect is estimated by two indices, reflecting the degree of deviation of the state of the body of the experimental animals from the norm and the probability of this deviation. Effective and ineffective combinations are determined by this system of equations when substituting in them the values of the toxic effect corresponding to its presence or absence. In turn, hygienically safe combinations are determined by a system describing ineffective combinations of exposure levels that include stock coefficients that are reasonable for each agent. This system can be adopted as an experimentally valid hygiene regulation, which has the following advantages. It is determined by the results of the study of the joint rather than isolated action of agents, does not require the fulfillment of any conditions about the nature of this action (isoadditivity, etc.), and also takes into account not only the degree of deviation of the state of the organism of the experimental animals from the norm, but also the probability this deviation. In order to obtain the necessary information, we propose plans for experiments in which the number of groups of experimental animals is only one more than the number of cooperative agents. An example of the proposed approach is given.

scholarly journals Eco-innovation vs. environmental taxation: what is more effective for state budget?

2021 ◽  
pp. 312-323
Author(s):  
Yegana Hakimova ◽  
Yaryna Samusevych ◽  
Shahla Alijanova ◽  
Esmira Guluzade
Keyword(s):  
Random Effects ◽  
National Economy ◽  
Slovak Republic ◽  
The State ◽  
Environmental Taxation ◽  
Environmental Taxes ◽  
Panel Regression ◽  
State Budget ◽  
The Impact

The article is devoted to the comparative analysis of the use of environmental taxes and the introduction of environmental innovations in terms of impact on the parameters of revenues and expenditures of the state budget. The study includes 10 countries of Central and Eastern Europe (Bulgaria, Czech Republic, Hungary, Estonia, Latvia, Lithuania, Poland, Romania, Slovenia and Slovak Republic). The analysis period covers 2010–2019. Systematization of scientific research proves the importance of using different tools to ensure sustainable development and greening of the national economy. The main purpose of the study is to determine a more effective form of interaction between government and business in the process of transforming the national economy in the direction of more environmentally friendly products and technologies by economic and mathematical modeling of environmental taxes and eco-innovation impact of budget revenues and expenditures. The calculations consist on the several stages: 1) determining the list of relevant control variables using correlation analysis, which eliminates the problem of multicollinearity; 2) determination of the model specification (fixed or random effects) using the Hausman test; 3) identification of the generalizing effects of the impact of environmental taxation and the eco-innovation index on the indicators of budget revenues and expenditures using a generalized least squares panel regression model with random effects; 4) study of the impact of the main components of environmental taxes and components of the eco-innovation index on the parameters of the state budget using panel regression modelling; 5) determination of short-term and long-term effects of the impact of environmental taxes and eco-innovations on the parameters of budget revenues and expenditures bt auto-regression distributive lag modelling. Stata 12/SE software tools were used for calculations. The study indicates the need to transform approaches to the implementation of state environmental policy. Thus, it has been proven that government incentives for the introduction of environmental innovations in the economy can be more effective than increasing the burden of environmental taxes.

ASSESSMENT OF THE STATE OF AIR POLLUTION ON A SEGMENT OF THE CITY HIGHWAY (ON THE EXAMPLE OF MIRA AVENUE IN THE CITY OF OMSK)

2021 ◽  
Vol 72 (1) ◽  
pp. 88-95
Author(s):  
E.V. PARSAEV ◽  
◽  
I.A. TETERINA ◽  
P.N. MALYUGIN ◽  
◽  
...  
Keyword(s):  
Air Pollution ◽  
Traffic Management ◽  
Heavy Traffic ◽  
The State ◽  
Pollutant Emissions ◽  
Qualitative Assessment ◽  
Main Components ◽  
The Impact ◽  
The City

The article presents the results of experimental and theoretical studies aimed at performing a qualitative assessment of the impact of traffic management on the level of air pollution from traffic flows in different sections of one segment of the city highway. Assessment of the state of atmospher-ic air pollution on a highway with heavy traffic (Pr. Mira, Omsk city) was carried out on the basis of determination of carbon monoxide (CO) in the air as one of the main components of the exhaust gases of the traffic stream. Calculations are graphically presented, indicating the unevenness of the amount of pollutant emissions by one passenger car moving along a conditional segment of the city highway with various variations in traffic conditions due to traffic management.

scholarly journals Analysis of the level of technical development of mobile lifts with working platforms

2021 ◽  
Vol 1 (92) ◽  
pp. 149
Author(s):  
Igor Kyrychenko ◽  
Oleksandr Reznikov ◽  
Yurii Rukavyshnikov ◽  
Anton Knyshenko
Keyword(s):  
Statistical Data ◽  
General Trend ◽  
Technical Development ◽  
Technical Level ◽  
Operational Parameters ◽  
Technological Parameters ◽  
Development Methodology ◽  
The Impact ◽  
Further Development

Problem. Currently, there are about 150 manufacturers of mobile lifts with working platforms (MLWP), which constantly design and introduce into production new machines with expanded capabilities. Therefore, there is a need to determine the level of technical development of MLWP, which is not possible without the analysis of statistical data of their nomenclature depending on the classification features and operational parameters. Goal. The purpose of the work is to analyze the impact of classification features and operational parameters of MLWP on the level of their technical development. Methodology. The analytical methods of studying the statistical data were used. The methods of mathematical modulation were used to develop the general trend of the jib MLWP technical level. Results. As a result of the analysis the general trend of the technical level of the jib MLWP by the height of rise of the working platform depending on the weight of the machine, the general trend of the technical level of the jib MLWP by the magnitude of the working platform horizontal reach, and the general trend of the technical level of the jib MLWP by the height of rise of the working platform depending on the working platform horizontal reach were obtained. Originality. The telescopic and articulated lifts are usually considered as separate groups, although they have much in common, because at least one section of the jib of modern articulated lifts consists of retractable (telescopic) sections, so during the statistical analysis of the MLWP technical level, these machines were considered as a single group of jib machines. Practical value. With the help of the obtained statistical dependences of the jib MLWP technical level on the technological parameters of the machine, it is possible to assess the technical development of both an individual machine and a group of MLWP with the determination of trends for further development.

scholarly journals Experimental research on vibrational digging-up of sugar beet

2018 ◽  
Vol 5 (1) ◽  
pp. 30-41
Author(s):  
V. Adamchuk ◽  
V. Bulgakov ◽  
I. Holovach ◽  
Ye. Ignatiev
Keyword(s):  
Sugar Beet ◽  
Technological Process ◽  
Experimental Research ◽  
Statistical Processing ◽  
Technological Parameters ◽  
A Value ◽  
Crop Root ◽  
The Impact ◽  
Experimental Researches

The technological process of vibrational digging-up of sugar beet has spread in many sugar beet-sowing coun- tries. The experience of using this process demonstrated its advantages compared against other ways of dig- ging-up, but there have been scarce experimental researches of the vibrational digging-up of sugar beet from soil which makes this topic urgent for sugar beet production. Aim. The experimental determination of rational parameters and modes of the vibrational digging-up working tool to ensure the required quality of conducting the technological process of digging sugar beet from soil. Methods. The methods of planning a multifactor ex- periment, fi eld studies, statistical processing, regression analysis of the experimental data with building graphic curves were applied. Results. A new model of a tool for vibrational digging-up of sugar beet from soil has been elaborated. The accepted program and method were used to conduct experimental research on the impact of the main construction and technological parameters of the vibrational digging-up working tool of the beet harvester on the quality indices of performing the technological process of harvesting sugar beet. The energy parameters of new vibrational digging-up working tools were studied in fi eld conditions via registering the values of tenzometric sensors in different modes of the device and different parameters and working modes of the vibrational digging-up tools. Conclusions. It was established that there is a value of the vibration frequency and running depth in soil of the vibrational digging-up working tool for each value of the translational veloc- ity of the vibrational digging-up machine which corresponds to minimal losses and damage to crop roots. It was also found that the degree of crop root damage depends on the conditions of performing the technological process of vibrational digging-up (soil solidity and humidity), and the weight of damaged crop roots increases with the increase in solidity and the decrease in humidity of soil.

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