scholarly journals DETERMINATION OF THE MODE OF FUNCTIONING OF THE CENTRIFUGAL-GRAVITATIONAL SEPARATOR OF THE GRINDING DEVICE

2021 ◽  
pp. 64-71
Author(s):  
Anatolii Spirin ◽  
Igor Tverdokhlib ◽  
Mykhailo Zamriі
Keyword(s):  
Vertical Axis ◽  
Material Point ◽  
Conical Surface ◽  
Design Parameters ◽  
Rational Form ◽  
Direction Of Movement ◽  
Rotary Drum ◽  
Separation Of Mixtures

The peculiarity of harvesting legumes is the need to process their heap on grater devices with subsequent separation. To improve the technical and economic performance of seed heap processing equipment, it is advisable to combine wiping and separation operations by combining a grater working body and a separating rotating sieve of cylindrical or conical shape. The analysis of influence of geometry of rotary sieve drums allows to define the rational form and parameters of work of the separating device which will provide the necessary quality of seed material. Analysis of the literature on the processes of sieve separation of grain and seed mixtures showed the advantages of centrifugal separators with a rotating sieve surface. Improving the efficiency of separation of mixtures by rotary sieves is achieved by the simultaneous use of centrifugal, Coriolis and gravitational forces. The aim of the study is to increase the efficiency of separation of seed heaps of legumes after treatment with a grater device by determining the trajectory of the seeds along the rotational surfaces. Earlier, the authors developed a grater-separating unit in which a cylindrical perforated drum is used to remove unworn seeds. This design does not use the surface of the sieve effectively enough. To increase the uniformity of the load on the steaming surface of the rotary drum, it is advisable to reduce its area in the direction of seed movement. To do this, use a conical separating surface to reduce the radius of the cone in the direction of movement of the material. When considering the movement of a particle, it is represented as a material point with mass m moving along a conical surface that rotates around a vertical axis. As a result of theoretical researches the dependence which defines time of stay of a particle on a sieve depending on a coordinate (length of a generating cone) is received. A graphical interpretation of this dependence for certain values of design parameters is also presented. As a result of research, it was found that increasing the residence time of the material on the sieve due to the use of a conical surface increases the yield of pure seeds, and also contributes to the uniform loading of the sieve surface, which improves the quality of the source material.

scholarly journals CAUSES OF POOR QUALITY CASING OF DIRECTIONAL WELLS AT THE DRILLING DEPARTMENT «UKRBURGAZ» AND METODS FOR THEIR ELIMINATION

2019 ◽  
pp. 26-35
Author(s):  
I. M. Kovbasiuk ◽  
O. B. Martsynkiv ◽  
B. O. Martsynkiv
Keyword(s):  
Field Data ◽  
Drilling Fluid ◽  
Field Research ◽  
Poor Quality ◽  
Design Parameters ◽  
Geological Conditions ◽  
Casing Strength

The analysis of modern studies and field data relating to directional wells casing at the enterprises of “Ukrburgas” drilling company has been carried out in the article. In particular, complications with casing strings, which happened when casing directional wells at these enterprises, data on the non-admission of casing strings to the total depth, a brief description of works aimed at restoring the quality of well casing, are considered. Main reasons of complications, damages and failures during well casing process have been determined. It has been found out that casing string failures mostly happened in the areas of intensive wellbore deviation. The reasons of directional wells poor quality casing taking into account the results of new theoretical, experimental and field research have been systemized. Cases of wells poor quality casing are supposed to be divided into two groups: 1) casing strings damage, 2) non-admission of casing strings to the total depth and violation of string integrity. Each of the groups is classified in accordance with the types of poor casing. The main reason of directional wells poor quality casing are failures caused by wrong casing strength calculations, violation of casing well technology, casing strings wear, mining and geological conditions. The non-admission of the columns to the total depth and poor-quality joining of sections are minor, which arise due to the low passability of the well, inaccurate determination of the depth of the well, geological conditions, etc. Measures to prevent complications, damages and accidents during well casing, in particular, work on forming the necessary wellbore profile, maintaining the design parameters of drilling fluid, and compliance with the requirements of enterprise standards during preparation works, lowering, cementing and final casing works have been worked out.

Determination of Power Output and Impact on the Rheological Parameters of Raw Materials during Rolling

2016 ◽  
Vol 20 (2) ◽  
pp. 135-142
Author(s):  
Petro Daniłowicz Stadnyk ◽  
Igor Grigorowicz Dobrotvor ◽  
Katarzyna Szwedziak
Keyword(s):  
Power Output ◽  
Raw Materials ◽  
Rolling Process ◽  
Product Layer ◽  
Rational Approach ◽  
Rheological Parameters ◽  
Design Parameters ◽  
Layer Analysis

AbstractThe paper presents mathematical modelling of determining the power output over the rolling materials in the gap rotating rollers taking into account the rheological parameters of the final product. Determination of these parameters will reduce energy consumption, increase efficiency and reduce loss of material during production. This solution, suggested in the article, allows determination of the overall quality of the rolled product layer. Analysis of experimental results revealed that the main features of the machine provide the necessary stable shape products and provide good rheological parameters of these products. Rheological testing indicators allow for a rational approach to a decision to operate a rolling process. At the same time they improve quality control methods and will have an impact on the design parameters of rollers and modes of chambers. The proposed method not only allows obtaining a predetermined pressure, but also allows defining the optimal shape of the gap, wherein the pressure gradient is constant.

scholarly journals REGARDING THE QUALITY OF ASSEMBLY OF THE SCREW CONNECTIONS OF THE MOUNTING ASSEMBLY OF BALL BEARINGS

2021 ◽  
Vol 3 (163) ◽  
pp. 12-15
Author(s):  
V. Lus’
Keyword(s):  
Dynamic Model ◽  
Primary Objective ◽  
Design Parameters ◽  
Ball Bearings ◽  
Threaded Connection ◽  
Vibration Tests ◽  
Technological Frame ◽  
And Control

Application of method of vibrodiagnostics is based on the presence of cross-correlation dependences of dynamic descriptions of all knots from contact pressure in connection through the change of inflexibility of joints. The change of inflexibility of separate elements causes the change of the resulted inflexibility of knot, and at the same time and characteristic it to dynamic descriptions of the artificially created oscillation field: frequencies and amplitudes of resonance vibrations, indexes of damping, phase correlations. There is a task of determination of method of control of the most responsible technological frame-clamping operations at making of such objects: quality of contact connections, ball-bearing knots, fixing of previous pull of ball-bearings and control of isotropicness, inflexibility and dissipative descriptions of the system of pendant of rotor at all stages of drafting, including in the functional state. The primary objective of this work is research of question of influence of non-perfect resiliency and different inflexibility of the supporting bearings on the dynamic reaction of object at external oscillation excitation, determination of estimation of the different inflexibility bearings, determination of accordance of axial inflexibility of ball-bearings supports, them by a basic value. The dynamic model of knot and certain functions of influence of parameters of the system is considered on high-quality indexes. The dynamic model of precision rotor system (PRS) is investigated. Vibration tests at the stage of assembling the structure of the ORS showed that in the process of assembling the elements change the natural frequencies of the system and the quality factor of the oscillating circuits. The resulted dependences allow giving an estimation degree of non-linearity of resilient description and, as a result, different inflexibility of bearings supports as a result of oscillation researches. The sensitivity functions of the design parameters of the complex press-threaded connection in relation to the vibration dynamic parameters – frequencies and amplitudes of resonant oscillations – do not differ qualitatively from those obtained previously.

Tingkat Pemahaman Kompetensi Guru Pada Mahasiswa Pendidikan Geografi Sebagai Calon Guru Geografi

2020 ◽  
Vol 21 (1) ◽  
pp. 102-117
Author(s):  
Novia Zalmita ◽  
Muhajirah Muhajirah ◽  
Abdul Wahab Abdi
Keyword(s):  
Prospective Teachers ◽  
Prospective Teacher ◽  
Quantitative Description ◽  
Population Data ◽  
Geography Education ◽  
Teacher Competence ◽  
Education Department ◽  
Long Time

One that influences human resource indicators is education. The teacher is a profession as a job of academic specialization in a relatively long time in college. Understanding related to teacher competence is very important to have by a prospective teacher because it can affect the quality of performance as a professional teacher. The teacher's competence is known as pedagogic, professional, social and personality competencies. The issue in this study is how the competency of the teacher of the Department of Geography Education FKIP Unsyiah as a prospective teacher of geography? The purpose of this study was to determine the competence of teachers in the Department of Geography Education FKIP Unsyiah as prospective geography teachers. Quantitative description approach is used in this study to find answers to the issue. The population in this study were students of the Department of Geography Education FKIP Unsyiah class of 2015 and 2016 who had been declared to have passed the Micro Teaching and Magang Kependidikan 3 course totaling 50 people. Because the population is small and can be reached, the determination of the sample using total sampling techniques so that the sample in this study is the whole population. Data collection is done by distributing test questions to respondents. The data was analyzed using the descriptive statistics percentage formula. The results of the study indicate that the level of teacher competence of Geography Education Department students as prospective teachers is in the moderate category, namely as many as 22 respondents (44%). A total of 12 respondents (24%) were in the high category, 15 respondents (30%) were in the low category and 1 respondent (2%) were in the very low category.

Calculating the aerodynamics of vertical axis wind turbines

2012 ◽  
Vol 34 (3) ◽  
pp. 169-184 ◽  
Author(s):  
Hoang Thi Bich Ngoc
Keyword(s):  
Wind Turbine ◽  
Incidence Angle ◽  
Vertical Axis ◽  
Rotor Blades ◽  
Vertical Axis Wind Turbine ◽  
Horizontal Axis Wind Turbine ◽  
Velocity Triangle ◽  
Relationship Of ◽  
The Relationship

Vertical axis wind turbine technology has been applied last years, very long after horizontal axis wind turbine technology. Aerodynamic problems of vertical axis wind machines are discussible. An important problem is the determination of the incidence law in the interaction between wind and rotor blades. The focus of the work is to establish equations of the incidence depending on the blade azimuth, and to solve them. From these results, aerodynamic torques and power can be calculated. The incidence angle is a parameter of velocity triangle, and both the factors depend not only on the blade azimuth but also on the ratio of rotational speed and horizontal speed. The built computational program allows theoretically selecting the relationship of geometric parameters of wind turbine in accordance with requirements on power, wind speed and installation conditions.

Fluctuations of Annual Precipitation and Water Resources Quality in Ukraine

2016 ◽  
Vol 10 (4s) ◽  
pp. 621-629
Author(s):  
Valentina Pidlisnyuk ◽  
◽  
John Harrington JR ◽  
Yulia Melnyk ◽  
Yuliya Vystavna ◽  
...  
Keyword(s):  
Water Resources ◽  
Surface Waters ◽  
Precipitation Amount ◽  
Ion Concentration ◽  
Annual Precipitation ◽  
Resource Quality ◽  
Phosphate Ion ◽  
Regional Trends

The article focuses on examining the influence of fluctuations in annual precipitation amount on the quality of surface waters. Water quality was estimated with data on BOD, COD and phosphate–ion concentration within five selected regions of Ukraine. Analysis of the precipitation data (1991 – 2010) showed different regional trends. Using the statistics, determination of the interconnection between precipitation amount and water resources quality were done. The obtained regularities and associated uncertainties can be used for prediction of changes in water resource quality and as a guide for future adaptation to possible climate change.

POTENSI PENGEMBANGAN SADE SEBAGAI DESA WISATA LOMBOK

2016 ◽  
Vol 20 (2) ◽  
pp. 69-82
Author(s):  
W. Suprihatin ◽  
H. Hailuddin
Keyword(s):  
Analytical Hierarchy Process ◽  
Environmental Aspect ◽  
Priority Level ◽  
Highest Weight ◽  
Local Tradition ◽  
Tourist Village ◽  
Hierarchy Process ◽  
Initial Pattern

The background of the problems in this study is the decreasing quality of Sade hamlet amid rising tourist arrivals. From the environmental aspect, the conditions of the hamlet began to decline, in which the initial pattern of Sade has started a lot of changes towards the deficient and began to leave the local tradition. One effort to improve the condition of Sade hamlet in social, cultural and the environmental aspect is through the formulation of a sustainable structuring, the presence and identity maintaining and making a sustainable Tourism Village. Through analysis of AHP (Analytical Hierarchy Process) by collecting the perceptions of some experts through interviews and questionnaires, obtained by weighting the priority of the experts, namely the preservation of culture as an element of priority-level goals to be achieved in the development of Sade Hamlet as a tourist village at 0,476. While the determination of the level of the main criteria in the achievement of these objectives is the highest weight while maintaining a typical village environment at 0.319. Priority strategies that get the highest weight of the experts is that Sade Hamlet Revitalization with a priority weighting of 0.583. The second priority is the relocation of Hamlet at 0.235. Lowest weighting or last priority is Replication Sade Hamlet at 0.182.

Automation of selected brazes' dynamic properties in high-temperatures' measurement process

2013 ◽  
Vol 18 (2-3) ◽  
pp. 33-41
Author(s):  
Dominik Sankowski ◽  
Marcin Bakala ◽  
Rafał Wojciechowski
Keyword(s):  
Surface Tension ◽  
High Temperatures ◽  
Dynamic Properties ◽  
Automatic Measurement ◽  
Measurement Methodology ◽  
Joining Process ◽  
Wetting Force ◽  
Research Grant

Abstract The good quality of several manufactured components frequently depends on solidliquid interactions existing during processing. Nowadays, the research in material engineering focuses also on modern, automatic measurement methods of joining process properties, i.a. wetting force and surface tension, which allows for quantitative determination of above mentioned parameters. In the paper, the brazes’ dynamic properties in high-temperatures’ measurement methodology and the stand for automatic determination of braze’s properties, constructed and implmented within the research grant nr KBN N N519 441 839 - An integrated platform for automatic measurement of wettability and surface tension of solders at high temperatures, are widely described

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