scholarly journals Profile and contour grinding of compressor blade butts

2016 ◽  
Vol 1 (1) ◽  
pp. 15-19
Author(s):  
В. Полетаев ◽  
V. Poletaev ◽  
Е. Цветков ◽  
E. Tsvetkov

The existing technologies of production of compressor blade butts related with traditional machining methods, including broaching and milling. Application of these machining methods requires further superfinishing operations to ensure the required quality of compressor blades. The automated highly-productive grinding of blade butts is an effective method to improve performance and quality of blade production. The technologies of profile and contour grinding of blades of a rotor and a compressor stator provide an automated machining of the outer parts contour in the same coordinate system, implement machining based on 3-D models of theoretical blade surfaces, ensure the required quality parameters of the part surface layer without additional finishing operations.

Author(s):  
Д.Г. ЧУРИЛОВ ◽  
И.С. АРАПОВ ◽  
А.В. СТАРУНСКИЙ ◽  
С.Д. ПОЛИЩУК

Проблема и цель. Установлено, что функциональное действие машин в значительной мере определяется параметрами качества их поверхностного слоя. Цель работы – обеспечение качества поверхностного слоя деталей одним из наиболее эффективных способов, обеспечивающих управление в широком диапазоне показателями качества обработки деталей поверхностным пластическим деформированием (ОУО ППД). Одни и те же параметры качества поверхностного слоя можно получить, используя различные методы и режимы ОУО ППД. Для их оценки необходимо определение трудоемкости операции. Следовательно, имеет место совокупность научно-технических задач, решение которых позволяет разработать методологию, алгоритм и программу выбора оптимального метода и условий ОУО ППД, обеспечивающих требуемые параметры качества поверхности при минимальной технологической себестоимости, что дает значительный экономический эффект. Методология. Одним из способов обработки деталей при восстановлении служит алмазное выглаживание после процесса шлифования. Выглаживатель – кристаллический алмаз – перераспределят металл поверхностного слоя, при этом меняется микрорельеф. После алмазного выглаживания увеличивается надежность, долговечность деталей, износостойкость. Для достижения цели предлагается использование двухзвенных оправок, которые позволяют исключить биение обрабатываемой поверхности. Структурный эквивалент механизма близок к кривошипно-шатунному механизму, в отличие от которого радиус обрабатываемой детали распределяется по дуге. Изменения силы выглаживания устанавливают связь между статической силой и силой инерции. Статическую силу сглаживания можно определить, зная основные технологические параметры и процессы. Сила инерции зависит от массы подвижного звена оправки. Результаты. Результаты настоящего исследования показали: к числу задаваемых параметров относятся масса подвижного звена оправки, диаметр детали, скорость скольжения, эксцентриситет, постоянная механизма и сила инерции. Найдены разрешенные частоты вращения в зависимости от диаметра детали. Заключение. Данная методика может быть применена для восстановления рабочих поверхностей поршневых пальцев автотракторных дизельных двигателей сельскохозяйственного назначения и позволяет снизить уровень шероховатости поверхности обрабатываемых деталей. Problem and purpose. Problem and purpose. It has been established that the functional action of machines is largely determined by the quality parameters of their surface layer. The purpose of the work is to ensure the quality of the surface layer of parts by one of the most effective methods that provides control over a wide range of quality indicators for processing parts by surface plastic deformation (SPD). The same parameters of the quality of the surface layer can be obtained using different methods and modes of SPD. To assess them, it is necessary to determine the complexity of the operation. Consequently, there is a set of scientific and technical problems, the solution of which makes it possible to develop a methodology, an algorithm and a program for choosing the optimal method and conditions for SPD, which provide the required surface quality parameters at a minimum technological cost, that gives a significant economic effect. Methodology. One of the methods of processing parts during restoration is diamond burnishing after the grinding process. The smoother or the crystal diamond will redistribute the metal of the surface layer, thus changing the microrelief. After diamond burnishing, reliability, durability of parts, and wear resistance increase. To achieve the goal, it is proposed to use two-link mandrels, which allow to exclude the beating of the treated surface. The structural equivalent of the mechanism is close to the crank gear, in contrast to which the radius of the workpiece is distributed along the arc. Changes in the smoothing force establish a relationship between static force and inertial force. The static smoothing force can be determined by knowing the basic technological parameters and processes. The force of inertia depends on the mass of the moving link of the mandrel. Results. The results of this study showed that the parameters set included the mass of the movable link of the mandrel, the diameter of the part, the sliding speed, the eccentricity, the constant of the mechanism and the force of inertia. The permitted speeds were found depending on the diameter of the part. Conclusion. This technique can be used to restore the working surfaces of the piston pins of automotive diesel engines for agricultural purposes and can reduce the level of surface roughness of the processed parts


Author(s):  
I.A. Sharonov ◽  
◽  
V.I. Kurdyumov ◽  
V.V. Kurushin ◽  
V.E. Proshkin ◽  
...  

Tillage rollers have been developed that provide the required quality of tillage of the surface layer of the soil during sowing. Their optimal design parameters and operating modes have been substantiated. The increase in yield was determined when using the developed tools in comparison with the serial ones. The annual economic effect was revealed, which amounted to 4,648 to 5,045 rubles per one hectare of spring wheat crops.


Author(s):  
V. F. Bezjazychnyj

The justification of the feasibility of determining the cutting modes when processing with a blade tool with optimization to minimize the wear of the cutting wear is given, i.e. for its maximum resistance and at the same time to ensure the required quality indicators of the material of the surface layer of the part after processing. The initial data for the calculation and examples of calculating the cutting mode and surface layer quality indicators are given. Nomograms for determining the cutting modes, taking into account the quality indicators of the surface layer, are of practical interest for technologists of machine-building enterprises.


Author(s):  
Ю.А. Клименко ◽  
А.П. Преображенский

В статье рассматривается решение задачи моделирования процесса управления электрическими нагрузками для повышения качественных показателей электрической энергии в распределительных электрических сетях 0,4 кВ на основе использования адаптивной системы управления электрическими нагрузками. Проведен анализ существующих методов снижения неравномерности распределения мощностей. Алгоритм процесса управления электрическими нагрузками в распределительных электрических сетях, алгоритмы анализа распределения мощностей и напряжений по фазам сети, а также алгоритм устранения отклонений напряжения, которые могут быть использованы при разработке электрооборудования. для обеспечения необходимого качества электроэнергии. The paper considers the solution of the problem of modeling the process of controlling electrical loads to improve the quality parameters of electrical energy in distribution electrical networks of 0.4 kV based on the use of an adaptive system for controlling electrical loads. The analysis of existing methods of reducing the uneven distribution of capacities is carried out. An algorithm for the process of controlling electrical loads in distribution electrical networks, algorithms for analyzing the distribution of powers and voltages over the phases of the network, as well as an algorithm for eliminating voltage deviations, which can be used in the development of electrical equipment to ensure the required quality of electricity, have been developed.


Author(s):  
S. V. Zakharov ◽  
M. T. Korotkikh

The study analyzed scientific resources, collected statistics on composition of electrolytic solutions for electrolytic plasma processing of aluminum alloy D16. Moreover, a procedure for determining the potential components of the electrolytic solution has been found and there has been developed an electrolytic solution that excludes surface etching and provides the required quality of the surface layer. Finally, rational technological regimes have been determined


2016 ◽  
Vol 2016 (2) ◽  
pp. 156-166
Author(s):  
Петр Тихомиров ◽  
Petr Tikhomirov ◽  
Елена Лемешева ◽  
Elena Lemesheva ◽  
Николай Булхов ◽  
...  

Contact rigidity of a joint is one of the main criteria of operability of forest cars. It defines vibration activity and durability of the tightened bolted connections therefore its assessment will allow to predict behavior of technical systems. In work the technique of an assessment of contact rigidity by means of the nerocomputer modeling allowing to consider parameters of quality of a blanket is presented. Results of re-searches allowed to receive mathematical models for contact rigidity. In the paper there is presented a procedure of contact rigidity estimate with the aid of neurocomputer modeling. A contact rigidity of a joint is one of the basic criteria of machine and mechanism capacity for work. It defines vibration activity and strength of tightened bolted connections therefore its estimate will allow forecasting the behavior of technical systems. Neurocomputer modeling is a promising method allowing taking into account quality parameters of a surface layer of machinery at the analysis of a deformed state.


2018 ◽  
Vol 33 (2) ◽  
pp. 62-70 ◽  
Author(s):  
A Hossain ◽  
MM Islam ◽  
F Naznin ◽  
RN Ferdousi ◽  
FY Bari ◽  
...  

Semen was collected from four rams, using artificial vagina and viability%, motility% and plasma membrane integrity% were measured. Fresh ejaculates (n = 32) were separated by modified swim-up separation using modified human tubal fluid medium. Four fractions of supernatant were collected at 15-minute intervals. The mean volume, mass activity, concentration, motility%, viability%, normal morphology and membrane integrity% (HOST +ve) of fresh semen were 1.0 ± 0.14, 4.1 ± 0.1 × 109 spermatozoa/ml, 85.0 ± 1.3, 89.4 ± 1.0, 85.5 ± 0.7, 84.7 ± 0.5 respectively. There was no significant (P>0.05) difference in fresh semen quality parameters between rams. The motility%, viability% and HOST +ve % of first, second, third and fourth fractions were 53.4 ± 0.5, 68.2 ± 0.3, 74.8 ± 0.3 and 65.5 ± 0.4; 55.5 ± 0.4, 66.2 ± 0.4, 74.5 ± 0.3 and 73.6 ± 0.3 and 66.7 ± 0.5, 66.8 ± 0.5, 65.2 ± 0.4 and 74.7 ± 0.5 respectively. The motility%, viability% and membrane integrity% of separated semen samples differed significantly (P<0.05) between four fractions. The mean motility% and viability% were significantly higher (P<0.05) in third fraction (74.8 ± 0.3%), whereas the mean HOST +ve% was significantly higher (P<0.05) in fourth fraction (74.7 ± 0.5). All quality parameters of separated spermatozoa were significantly (P<0.05) lower than that of fresh semen. The pregnancy rates were higher with fresh semen (71%) in comparison to that of separated sample (57%).Bangl. vet. 2016. Vol. 33, No. 2, 62-70


In construction production, the safety of constructing buildings and structures is achieved by ensuring the required quality as a result of systematic construction control based on the implementation of a complex of technical, economic and organizational measures at all stages of the object's life cycle. The article deals with the actual problem of improving the quality of construction products-buildings and structures in conjunction with the activities of construction control bodies. The article presents the advanced foreign and domestic experience of ensuring the quality control at the construction sites, providing for the prevention of the underlying causes of defects and increasing the interest of the contractors directly. On the basis of the analysis of the current situation with quality control at the construction market, ways to improve its efficiency by developing a unified system of technological implementation of relevant requirements for the quality of construction products, determining the rational number and business load of construction control engineers, as well as the active activities of self-regulatory organizations in this area are offered.


2014 ◽  
Vol 2 (2) ◽  
pp. 93-100
Author(s):  
Shahnaj Yesmina ◽  
Moushumi Akhtarb ◽  
Belal Hossain

The experiment was conducted to find out the effect of variety, nitrogen level and harvesting time on yield and seed quality of barley. The treatments used in the experiment consisted of two varieties viz. BARI Barley 4 and BARI Barley 5, three harvesting time viz. 35, 40 and 45 Days after Anthesis (DAA) and nitrogen levels viz. 0, 70, 85 and 100 kg N ha-1 . The experiment was laid out in a spilt- spilt-plot design with three replications assigning the variety to the main plot, harvesting time to the sub-plots and nitrogen level to the sub-sub plots. Variety had significant effects on the all yield attributes except fertile seeds spike-1 . Seed quality parameters viz. normal seeds spike-1 , deformed seeds spike-1 , germination (%) and vigour index were statistically significant. The variety BARI Barley 5 produced higher grain yield and seed quality than BARI Barley 4. Grain yield from BARI Barley 5 and BARI Barley 4 were 4.59 t ha-1 and 4.24 t ha-1 , respectively. Significantly, the highest 1000-seed weight (46.90 g) was produced by BARI Barley 5 than (37.90 g) BARI Barley 4. The result revealed that harvesting time had significant effect on yield and yield attributes and seed quality parameters. Seed yield was highest (4.65 t ha-1 ) when the crop harvested at 40 DAA and it was increased linearly from 35 DAA. Maximum quality seed and 1000-seed weight (43.20 g) was obtained when the crop harvested at 40 DAA. All the yields, yield attributes and seed quality parameters were significantly influenced by nitrogen levels. The highest grain yield (5.14 t ha-1 ) was obtained when BARI Barley 5 variety was fertilized by 100 kg N ha-1 and the lowest (3.14 t ha-1 ) was obtained from control treatments. Normal seeds spike-1 , vigour index, germination (%) were better at 85 kg N ha-1 in variety of BARI Barley 5 than BARI Barley 4. So it can be concluded that BARI Barley 5 showed better result when fertilized with 100 kg N ha-1 and harvested at 40 DAA for getting maximum yield and 85 kg N ha-1 and harvested at 40 DAA for getting better quality seed.


Author(s):  
G.B. Lyubomirsky ◽  
T.L. Redinova

This article assesses the reliability, constructive validity and reproducibility of a special questionnaire for determining the quality parameters of rendering physiotherapeutic care to patients with chronic generalized periodontitis. The analysis of literary sources showed that there are studies of quality of dental services, however, we have not met with research into the quality and comfort of physiotherapy procedures for periodontal patients. At the same time, the importance of this issue is obvious and requires study and analysis. Without making judgments about the quality of the service, a full-fledged medical dental procedure can not take place. The assortment of physical devices and methods grows annually, their use in the periodontoloical treatment is not always sufficiently justified, the effectiveness is not always confimed therefore it is important to pay attention not only to the marketing efforts directed by the clinics for comfort, but also to analyze the ideas about the quality of the clinical characteristics of physiotherapeutic procedures.


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