The article theoretically compares differences between two main modern milling machines manufactured in foreign countries and an obsolete machine-tool in Uzbekistan to have been made modernization by ...being equipped with new working parts to make it work with accuracy in terms of other important criteria such as precision of machine-tools, userfriendliness and economic aspects. The results of the analysis are expected to give potential insight into up to date milling machines for students who study in mechanical engineering and business people having desire to establish metal processing factory in Uzbekistan and servicing them to know important aspects in terms of the cost of brand-new milling machines and their working efficiency in compared to other typical obsolete machine-tools to have been used for a long time.
We have offered a constructive flow sheet of a root cleaner. Theoretical and experimental studies of roots purification process have been performed. We have also substantiated the main structural and ...regime pa-rameters of the proposed cleaner
New designs of the working parts of different types of equipment used in chemical and food plants and in related plants that maintain a constant temperature in these parts and, consequently, a stable ...thermal regime in the course of processing phases that are in contact with these parts are considered. It is assumed that the working parts are fabricated from magnetic substances with Curie point corresponding to the temperature at which the production process transpires.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In a sewing process, there is a close interaction between several factors: the working parts of the sewing machine which are actioned by an electric drive, the material (type, number of layers, the ...relative position of the layers) with different parts of the sewing machine and the worker (level of qualification). The result of this complex interaction is the seam. A good correlation between the working parts of the sewing machine determines a good seam, which is visible when one inspects the aspect of the garment. It is important for a clothing engineer to understand the mechanisms of a sewing machine (how they should work, as well as the correlation between their movements) because the final result (the seam) must fulfil the quality requirements. The interactions between the working parts of the sewing machine are analysed by taking into consideration the stages of the stitching process and the cyclorama of the sewing machine. A cyclorama is a graphical representation of the correlation between the active routes between all of the components of the sewing machine involved in the stitching process. The active course of a working part (component) engaged in the process as mentioned above is defined as the time it needs to make a complete movement (a point placed on the element describes a full trajectory). The active work part rate is the time in which the machine part takes part in the stitching process, and it is determined by the rotation angle of the main shaft (or the flywheel) measured from the moment when the working part gets involved in the process until the one it ceases to be so. In this paper, the authors present the stages of designing the cyclorama of a sewing machine used in evaluating if it is working correctly or not. If they are provided with video tutorials, the students will be able to understand the moments in which the components of the sewing machines become involved in the process and the ones in which they cease to do so, their role in the process of sewing, as well as the relative positions of the working parts at specific moments. The cyclorama is useful in determining the angles of rotation of the main shaft corresponding to the active races of each working part.
One of the objectives of dairy farming is to further increase the rate of milk production by increasing the milk productivity of cows. The most important reserve for increasing milk productivity is ...the use of milking equipment that best suits animal physiology, as well as its proper selection and operation. The analysis of existing milking device designs allowed to draw a conclusion that one of their main drawbacks is an extremely hard influence on udder receptors and consequently inhibition of milking reflex, which results in the decrease of milking intensity of a cow and in the decrease of milk yield. It is established that the most responsible element of the milking machine is milking cups equipped with teat tubes, which directly contact with an animal and are the actuating mechanisms. The research of deflection of symmetrical working part of a teat tube is based on the known principles of liquid (gas) and solid mechanics, theory of elasticity and resistance of materials, as well as of mathematical analysis. The equation of the maximum radial deflection of the working part of teat tube of the milking machine which allows to determine the interrelation of the deformation with mechanical characteristics of a used material, the basic constructive and dynamic parameters is derived. Besides, the given equation allows to determine the minimum necessary height of the working part of the teat tube with the minimum allowable thickness for creation of the wave effect of extrusion from sucker to diverter in a squeezing stroke while designing the milking machine with the squeezing effect.
Polypropylene is one of the most popular thermoplastic materials used in industry. To produce goods from this material, the ultrasonic welding method is often used. However, despite a large number of ...scientific papers, the influence of some parameters of the ultrasonic welding mode on the strength characteristics of polypropylene joints remains unstudied. The paper presents the results of experimental studies of contact spot ultrasonic welding of plates 3 mm thick made of 01003-26 grade polypropylene. The authors considered the process of gradual penetration of the ultrasonic tool working face into polypropylene to a depth equal to the total thickness of the welded plates. Statistical dependences of the depth of the tool face penetration into the material and the force of material separation on the ultrasound exposure time are obtained. The influence of the depth of the ultrasonic tool working face penetration on the tearing force of welded specimens is determined. A significant increase in the tearing force from 150 to 400 N was found at the tool penetration depth of more than 3.5 mm due to an increase in the nominal area of mutual mixing of the material between the welded plates caused by the flow of molten material into the gap. The authors proposed a hypothesis about the flow of the molten material in the direction opposite to the direction of penetration of the working tool by forming traveling Rayleigh waves. However, its confirmation requires additional studies of the influence of the ultrasonic welding mode parameters and the size of the gap between the parts to be joined on the rate of the molten material flow into the gap.
The paper presents the way to perform a static analysis with finite elements for the working part of a subsoiler, together with its results. The analysis was made for two different working regimes: a ...regime in which the working depth of the subsoiler is 0.3 m, and the speed of advance of the aggregate during the work is 2.777 m/s and one in which the working depth is 0.4 m, and the speed of advance is 2.222 m/s. The results of this paper are addressed first of all to the designers of agricultural machines for soil tillage, but not only.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Purpose. Obtaining suitable indicators for profile track classification (combining a diversity of its individual elements) to enhance the bandwidth of plots. Methodology. Analysis was done with ...polygon profiles. Rectified profile of each plot was grouped by the steepness of the elements within the increment of 1-2 %. For each plot was determined magnitude of the estimated rise and medium-sized rise on the working part of the profile. Longitudinal profiles were classified into four types by the magnitude of the proportion of light elements profile and estimated rises. Classification criteria are given for these four types of profiles with additional breakdown of each type into subgroups depending on the magnitude of the estimated rise. Findings.Researches proved that the maximum speed increasing on falls reduces the magnitude of the average fall and increases the proportion of the working profile. To test the proposed classification of profiles juxtaposition of freight trains time motion, calculated for real plots and by the corresponding typical profiles was carried out. Originality. Simplifying the calculations significantly, prevailing methods for assess profile track do not provide the full and accurate representation of the actual character impact of profile track at important tractional-operational and operational indicators. Conventional schemes do not accurately reflect the actual structure of track profiles, and therefore the use of them for concrete calculations can lead to wrong conclusions. Therefore, this classification of longitudinal profiles of the railway network becomes more important, which allow refer railway lines to a particular class upon longitudinal profile on the base of simple classifications marks and therefore use the tractional-operational calculations made for typical profiles in respect of certain lines. Practical value. Grouping of all explored plots by magnitude of average rise in the working part of the profile and analysis of the profile structure that is relevant to average rise, revealed that the proposed value of k is a simple, stable and specific indicator for the classification of the profile plot.
Мета. Робота спрямована на отримання стійких показників для класифікації профілю колії (об’єднуючих у собі різноманіття окремих його елементів) з метою посилення пропускної спроможності ділянок. Методика. Проведено аналіз профілів полігону. Випрямлений профіль кожної ділянки був згрупований за крутизною елементів у межах прирощення 1−2%. Для кожної ділянки визначалась величина розрахункового підйому та середнього підйому в робочій частині профілю. За величиною питомої ваги легких елементів профілю та розрахункових підйомів поздовжні профілі були класифіковані за чотирма типами. Приведені класифікаційні ознаки для цих чотирьох типів профілів із додатковою розбивкою кожного типу на підгрупи, в залежності від величини розрахункового підйому. Результати. Дослідниками доведено, що збільшення максимальної швидкості на спусках нівелює величину середнього ухилу та збільшує частку робочої частини профілю. Для перевірки запропонованої класифікації профілів виконано співставлення часу руху вантажних поїздів, розрахованого для реальних ділянок, та за відповідними їм типовими профілями. Наукова новизна. Суттєво спрощуючи розрахунки, існуючі способи оцінки профілю колії не дають достатньо повного та точного уявлення про дійсний вплив характеру профілю колії на важливі тягово-експлуатаційні та експлуатаційні вимірники. Умовні схеми недостатньо точно відображують структуру реальних профілів колії, у зв’язку з чим використання їх для конкретних розрахунків може привести до помилкових висновків. Тому більше значення набуває така класифікація поздовжніх профілів залізничної мережі, котра дозволила б на основі простих класифікаційних ознак відносити залізничні лінії до певного класу за поздовжнім профілем і, отже, використовувати стосовно певних ліній тягово-експлуатаційні розрахунки, виконані для типових профілів. Практична значимість. Групування усіх досліджених ділянок за величиною середнього підйому на робочій частині профілю та аналіз відповідної даному середньому підйому структури профілю показав, що запропонована величина к є простим, стійким та характерним показником для класифікації профілю ділянки.
In this paper, we used the dynamic strain measurement method to measure the top-cutter machine of cotton’s stress under its working state. With sorting out data and analyzing it, we obtained the ...stress condition of the framing and the working parts. And the measurement result could be used to analyze the axle’s fatigue strength and check whether it was safe or not. It provided integrant basis for the further design of the machine.
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