scholarly journals Comparative experimental studies of the main electrical parameters of electrical equipment insulation after drying by various methods

2021 ◽  
Vol 2131 (4) ◽  
pp. 042076
Author(s):  
E Dulskiy ◽  
V Kruchek ◽  
P Kolpahchyan

Abstract The article is devoted to the assessment of the comparative experimental studies’ results of various technologies for drying impregnated insulation of power electrical equipment in the process of manufacturing and repair: standard technology, which provides for convective drying using high-power electric ovens, and the proposed technology and methods for accelerated drying in hardware complexes using infrared (IR) radiation. In particular, the article presents the results of the polymer insulation surface microstructure analysis after drying by the indicated methods. The research was carried out in an industrial environment, using specialized certified equipment. In theoretical terms, the article presents the calculations on the rationale for the use of IR radiation during drying of a multilayer insulating structure of various compositions. The studies carried out confirm the hypothesis about the formation of microcavities on the surface and in the thickness of the polymer insulation when using convection during drying, which reduce the quality and reliability of the electrical equipment insulation as a whole. At the same time, the proposed technology and technique for accelerated drying of electrical equipment insulation using IR-radiation gives an opportunity to improve the quality of the resulting polymer insulation, increasing its reliability. In addition, this technology can significantly increase the productivity of insulation repair and reduce energy costs.

2021 ◽  
Vol 43 (3) ◽  
pp. 24-29
Author(s):  
Zh. Petrova ◽  
V. Paziuk ◽  
P. Vishnevsky ◽  
D. Grakov ◽  
О. Grakov

Known methods of production of dried cabbage are long-term production processes that take place within 12… 24 hours. Therefore, it is necessary to develop new methods of drying and intensification of this process. The article presents experimental studies of the kinetics of the drying process of white cabbage with different energy supply and their combinations, such as convective, infrared and convective-infrared drying methods. The main criterion for choosing a rational mode of drying is the quality of raw materials after heat treatment, in particular the visual assessment of color by temperature. During convective drying, the analysis of temperature regimes for process intensity and quality of raw materials was performed. The drying mode of 60ºC which satisfies all requirements for quality of material was chosen. To speed up the process, it is proposed to reduce the drying time by introducing a step mode of 80 / 60ºC, which also reduces the energy component. Infrared radiation intensifies the process due to the rapid heating of the material, but in turn it burns. Therefore, a combined convective-infrared method is proposed in which the temperature in the product did not exceed 60 ° C. This method of drying showed good results with a shorter drying time.Infrared radiation intensifies the process due to the rapid heating of the material, but in turn it burns. Therefore, a combined convective-infrared method is proposed in which the temperature in the product did not exceed 60 ° C. This method of drying showed good results with a shorter drying time.


2021 ◽  
Vol 264 ◽  
pp. 04042
Author(s):  
Nikolay Aldoshin ◽  
Sherzod Kurbanov ◽  
Akmal Abdullaev ◽  
Alham Khujayev ◽  
Dilsabo Choriyeva

To improve the quality and energy indicators on the front plow in front of the housings, the angle axes are installed in the form of a triangular wedge. The purpose of the study is to substantiate the parameters of the angle-lift of the front plow, which provides high-quality performance of the technological process according to agrotechnical requirements with the lowest energy costs for smooth, rowless plowing. The research uses the laws and rules of theoretical mechanics, mathematical statistics, mathematical planning of experiments, and methods of strain measurement, as well as the methods given in existing regulatory documents. Based on the study of the process of interaction of the carbon monoxide with the soil, analytical dependences are obtained that allow us to determine the parameters of the carbon monoxide. According to the results of theoretical and experimental studies, it was found that the required quality of tillage with a front plow following the established agrotechnical requirements with minimal energy consumption is provided at the height of 22 cm, a length of 27 cm, a wing angle of 32° and an angle of inclination of the side face of 36°.


2021 ◽  
Vol 37 ◽  
pp. 00044
Author(s):  
Maxim P. Erzamaev ◽  
Dmitry S. Sazonov ◽  
Leila S. Kurmanova ◽  
Evgeny S. Nesterov ◽  
Alexey E. Shlykov

The paper proposes a new method for multistage plowing that implies loosening bottom soil and subsoil horizon simultaneously, followed by overturning the bottom soil without cutting, which improves the quality of soil cultivation, softens a plow sole and reduces energy costs. Experimental studies confirmed the theoretical relationship for determining the plowing resistance, both of certain working bodies of a section, and of a whole plow. The method proposed for multistage plowing that implies loosening the subsoil provides a decrease in plowing resistance by 8.3-9.8% compared to the existing double-depth plowing followed by loosening the subsoil.


Author(s):  
N. F. Timerbaev ◽  
R. G. Safin ◽  
D. F. Ziatdinova ◽  
T. O. Stepanova

Drying of wood materials is one of the most important processes not only of wood processing, but also of many other industries. Drying processes involve the removal of moisture as a result of a phase transition from a liquid or solid to a gaseous state. This is due to the high energy intensity and duration of the process, especially for colloidal materials. The latter is due to the fact that with intensive drying the quality of the finished product often decreases, for example, when drying lumber cracks and warps occur, which is unacceptable in the manufacture of thermally modified products. In cases of thermochemical processing of dispersed materials, the quality of raw materials is determined only by the final moisture content of dispersed materials.Questions of heat and mass transfer during the drying of materials were carried out by Girsh M., Lykov A.V., Lurye M.V., Sazhin B.S., Dolinsky A.A., Golubev L.G., Rudobashta S.P., Shubin G.S., Romankov PG, Ginzburg A.S., Mikhailov N.V., Mushtayev VI. and etc. The paper deals with convective technology of dispersive materials. The zone of convective drying of dispersed materials is presented. Experimental and mathematical modeling of the drying process of wet dispersed materials before thermochemical processing was carried out. The results of theoretical and experimental studies of changes in temperature and humidity in the drying bin are presented. The nature of changes in temperature and humidity of dispersed particles in a drying bin was determined. The effective height of the layer in the counter-current dryer is determined by calculation, depending on the moisture content of the fuel and the temperature of the exhaust flue gases.


2020 ◽  
pp. 89-96
Author(s):  
Sergei S. Kapitonov ◽  
Alexei S. Vinokurov ◽  
Sergei V. Prytkov ◽  
Sergei Yu. Grigorovich ◽  
Anastasia V. Kapitonova ◽  
...  

The article describes the results of comprehensive study aiming at increase of quality of LED luminaires and definition of the nature of changes in their correlated colour temperature (CCT) in the course of operation. Dependences of CCT of LED luminaires with remote and close location of phosphor for 10 thousand hours of operation in different electric modes were obtained; the results of comparison between the initial and final radiation spectra of the luminaires are presented; using mathematical statistics methods, variation of luminaire CCT over the service period claimed by the manufacturer is forecast; the least favourable electric operation modes with the highest CCT variation observed are defined. The obtained results have confirmed availability of the problem of variation of CCT of LED luminaires during their operation. Possible way of its resolution is application of more qualitative and therefore expensive LEDs with close proximity of phosphor or LEDs with remote phosphor. The article may be interesting both for manufacturers and consumers of LED light sources and lighting devices using them.


Author(s):  
T. N. Antipova ◽  
D. S. Shiroyan

The system of indicators of quality of carbon-carbon composite material and technological operations of its production is proved in the work. As a result of the experimental studies, with respect to the existing laboratory equipment, the optimal number of cycles of saturation of the reinforcing frame with a carbon matrix is determined. It was found that to obtain a carbon-carbon composite material with a low cost and the required quality indicators, it is necessary to introduce additional parameters of the pitch melt at the impregnation stage.


2021 ◽  
pp. 002218562110039
Author(s):  
Eugene Schofield-Georgeson

Over the past two decades, industrial relations scholarship has observed a trend towards an increasingly punitive industrial environment along with the ‘re-regulation’ of labour law. Absent from much of this literature, however, has been an empirical and historical measurement or comparison of the scale and quality of this systemic change. By surveying coercive and penal federal industrial legislation over the period 1901–2020, this study shows empirically that over the last 40 years, there has been a steep increase in the amount of coercive federal labour legislation in Australia. It further measures and compares the volume of coercive labour legislation enacted specifically against ‘labour’ and ‘capital’ or both throughout the same period (1901–2020). Analysis reveals a correlation between a high volume of coercive labour legislation with low levels of trade union power and organisation. Argued here is that coercive labour legislation has been crucial to transitioning from a liberal conciliation and arbitration model of Australian industrial relations towards a neoliberal framework of employment legislation. In the former, regulation was more collective, informal and egalitarian (embodied by the sociological concept of ‘associative democracy’). Under a neoliberal framework, regulation is now more individualised, technical, punitive and rarely enforced, resulting in less equal material outcomes.


1986 ◽  
Vol 40 (5) ◽  
pp. 636-641 ◽  
Author(s):  
P. G. Varlashkin ◽  
M. J. D. Low ◽  
G. A. Parodi ◽  
C. Morterra

FT-IR photoacoustic (PA) and also photothermal beam deflection (PBD) spectra were recorded with the same particulate samples (graphite, charcoal, aspirin, and silica) under the same conditions in order to compare the quality of the spectra obtainable with the two techniques. A PA cell fitted with windows for the PBD laser probe beam was used, and PA and PBD spectra of each sample were recorded at 8 cm−1 resolution at each of the four different interferometer scan velocities. Although the overall aspects of FT-IR/PA and FT-IR/PBD spectra are the same, the signal-to-noise ratios of PA spectra are appreciably better than those of PBD spectra because PBD detection is more prone to disturbance by vibration than is PA detection. Absorption bands appear at the same wavenumbers in PA and PBD spectra. However, the relative intensities of bands of PBD spectra depend on the absorptive properties of the powdered solids; with weak absorbers, some bands may not be detected at all. PAS can be used with all powders. PBDS is of little or no use for the examination of weakly absorbing powders unless they scatter IR radiation extensively.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Qurban A. Memon ◽  
Adnan Harb ◽  
Shakeel Khoja

The program assessment process combines assessments from individual courses to generate final program assessment to match accreditation benchmarks. In developing countries, industrial environment is not diversified to allow graduating engineers to seek jobs in all disciplines or specializations of an engineering program. Hence, it seems necessary to seek evolution of an engineering program assessment for specialized requirements of the industry. This paper describes how specialization-specific courses’ assessments are grouped per requirements and then integrated towards overall program assessment. A software program application is developed to automate this development to reduce assessment work and show equivalently as integration of specialization-specific assessments per outcome per term. The implementation also shows how outcomes are integrated per specialization-specific courses in order to judge the implementation of the program assessment. This effort is expected to help stake holders of the program to judge evolution and quality of specialization tracks vis-à-vis expectations of the local industry.


Author(s):  
V. N. Pristupa ◽  
D. S. Torosyan

The purpose of the work was to study and identify the main factors aff ecting the quantity and quality of beef produced and sold in the Southern Federal district. A comparative assessment of the growth, development, formation of meat productivity and quality of beef of young animals of beef, dual and dairy breeds with stall-pasture technology and intensive rearing in the industrial complex. Experimental studies have been carried out in farms in the Rostov region. The object of research was cows with calves of Kalmyk, Hereford, Aberdeen-Angus, Russian komolaya, Kazakh White-headed breeds, as well as young animals of the same breeds, in addition, Black-and-White and Swiss breeds. Removable live weight in Hereford steers at 18 months of age was 658,0 kg, and Aberdeen-Angus – 655,2 kg. Domestic steers of Kalmyk were 41–44 kg lower in live weight than their herdmates of two imported breeds. However, with intensive rearing at 18 months of age, steers of Kalmyk breed had a removable live weight of more than 613,7 kg and a carcass weight of 326 kg. The yield of hot carcass was 55,4 %, and the slaughter yield was 58,89 %, which was only 1–2 % lower than the world’s leading beef breeds. It has been found when analyzing the results of boning the half-carcasses of experimental steers that the biggest weight of half-carcasses and the content of muscle and fat tissue in them in absolute terms were in Hereford steers. Steers of Kalmyk breed took the third place in terms of weight of large-sized semi–fi nished products and signifi cantly lost to Aberdeen-Angus herdmates by 7,3 kg or 6,5 %, and Hereford steers by 9,2 kg or 8,3 %. The results obtained prove the expediency of using stallpasture technology in the dry-steppe zone of the Southern Federal district when rearing young animals for beef up to 350–400 kg live weight at 15 months of age and its subsequent intensive rearing under industrial technology, in order to obtain the live weight of more than 570 kg and produce cost-eff ective beef.


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