Introduction. The productivity and efficiency of earth-cutting and transport machines (ETM) of the waste type depends on the nature and physical and mechanical properties of soils, i.e. on strength, connectivity, humidity, compactness, climatic conditions and on the region of the Republic of Kazakhstan. According to Professor R.A. Kabashev, the regions of Kazakhstan have mainly clay, sandy, loamy, sandy-gravel, coarse- and semi-rocky soils. Different designs and shapes of cutter blades, and therefore mouldboards, are required to develop these categories of soils to minimise cutting and digging resistance. Improved blade and blade designs result in higher productivity and energy efficiency, and the traction factor of the bulldozer is used effectively.When studying and analyzing literature sources, scientists of CIS and foreign countries came to the conclusion that the theory of interaction of working bodies of earth-moving machines with soils, typical for the middle belt of Russia and Ukraine, which are characterized by some connection between particles of II, III categories of soil strength, was reasonably created. Mechanisms of interaction of such soils with bulldozing equipment differ from the processes occurring when digging unbound and dense loamy soils typical for Kazakhstan.The material of this article represents the establishment of rational forms of the heap and the determination of optimum parameters of the heap depending on the category of the ground being mined, i.e., the creation of an adaptive working organ (WO) of the bulldozer, corresponding to its profile with natural trajectory of ground formation formation.Materials and methods. As materials, different categories of soils were used, widespread in the region of Kazakhstan and the new design of the bulldozer blade, equipped with a variety of sets of knives, i.e. ordinary straight knives - for planning work and the development of I-III categories of soils; with medium protruding knives (MPK) - for the development of dense IV-V categories or with stepped knives - for the development of hard, strong soils, etc. The process of their interaction with the maximum formation of the prism of drawing the soil before the blade, using the graphic-analytical method of research, was investigated.Outcomes. Studying the processes of interaction of WO and bulldozer knives with different categories of soils, rational designs of knives designed for the development of various categories of soils were established. The optimal parameters of the blade with the maximum set of the drawing prism before the blade are determined. Also, the blade is equipped with side knife extenders, upper visors and side bevels. The radius of curvature of the blade in the cross-section corresponds to the natural angle of chip formation of the soil layer, which allows to reduce the resistance of digging the soil.Discussion and conclusion. Until now, scientists of the CIS and foreign countries in the field of WO ETM of the waste type have studied in detail in theoretical terms and experimentally established promising designs of WO and bulldozer knives. Numerous methods for determining the parameters of the WO of the bulldozer depending on the category of the developed soil and taking into account the traction factor of the propulsion system, etc. However, they missed the study, with the maximum set of the prism of drawing the soil in front of the blade, its area of contact from the frontal surface of the blade and at the same time, adapted in the cross-section of the blade (radius of curvature of the blade) with the natural trajectory of chip formation of the soil layer.Taking into account these provisions, we have developed several options for the location of knives on the blade, taking into account the developed categories of soils:- a bulldozer blade with side bevels of the frontal surface for soft (sandy) soils;- bulldozer blade with MPK, side scarves and upper side bevels for strong, clay soils;- bulldozer blade with side bevels and side knives-extenders for loosened soils;- bulldozer blade with MPK, side scarves, side knives-extenders and upper bevels for densely strong soils (medium loam). For all these options (4 types of blade) blade design and knife location, it is recommended to determine the optimal parameters of the blade, taking into account the development of the soil category.
Строительство автомобильных и железных дорог протяженностью несколько тысяч километров невозможно представить без участия универсального бульдозера. Одним из основных узлов бульдозера является рабочий орган. Производительность и энергоемкость бульдозера во многом зависят от того, какого типа форма отвала на нем установлена. Емкость (максимальный объем призмы волочения грунта) -одна из основных характеристик, определяющая высоту и ширину отвала, причем большинство производителей предлагают надставки (козырьки), позволяющие увеличить высоту отвала. Увеличение высоты отвала позволяет перемещать больше материала и уменьшает пересыпания через верхнюю часть отвала. С другой стороны, увеличение объема призмы волочения по ширине отвала устанавливают боковые щеки, которые придают отвалу форму ковша (трапециевидная). Они не дают перемещающемуся грунту высыпаться по бокам отвала (боковые валики), тем самым увеличивается объем данного материала. Однако чрезмерное увеличение емкости отвала потребует при работе дополнительных затрат мощности базового трактора, который вызывает увеличение нагрузки на узлы машины и ускоряет интенсивность их износа, особенно когда бульдозер перемещается вверх по уклону. Объем перемещаемого отвалом материала за один проход зависит от возможности изменения угла отвала относительно вертикальной и горизонтальной плоскостей. В современных конструкциях отвалов положение угла наклона регулируется четырьмя или шестью положениями, в зависимости от категорий разрабатываемого грунта. Целью исследования является оптимизация геометрических параметров и установление трапециевидной формы отвала с учетом взаимодействия его лобовой поверхности с сформированным объемом максимальной призмы волочения грунта в статическом процессе работы бульдозера.Материалы и методы. В качестве материалов применялись разрабатываемый грунт и отвал бульдозера, исследовался статический процесс их взаимодействия при максимальном формировании призмы волочении грунта перед отвалом с использованием методов исследования графоаналитическим и математическим способом вычисления. Результаты. Графоаналитическим и математическим вычислением оптимизирован процесс взаимодействия отвала с грунтом, определены максимальные (предельно-допустимые) параметры отвала с учетом тягового усилия трактора и категории разрабатываемого грунта.
Introduction. In modern market conditions, dump-type earth-moving transport machines especially need to analyse the marketing of these machines. Therefore, some acquired earth-moving machines during the development of soils with stony inclusions (typical for the RK) quickly wear out their cutting edges of the knife, then gradually fail the machines themselves, thereby not justifying their cost, i.e. are not operated effectively in practice. The goal is to choose from a variety of types of machines the most effective models of earth-moving and transport machines of the dump type, adapted to the conditions of the ground background of the Republic of Kazakhstan with the help of developed complex evaluative indicators.Methods and materials. As materials, the well-known 6 specific, generalized parameters and additionally developed by the authors of 20 assessment indicators (specific, generalized, differential and integral) were used to evaluate the competitiveness of the projected new design of the working body of the earth-moving transport machine of the dump type, as well as the operated these machines.Outcomes. As a result of the analysis of the interaction of the working body of the bulldozer with the developed soil and the study of their parameters, the estimates were developed and formed to assess the effectiveness of the bulldozer. The field tests of the proposed six promising design solutions for a bulldozer with different blades were carried out to compare the structures with each other and evaluated them in quantitative form. According to the calculated estimates, the efficiency of the bulldozer blade was evaluated for six variants of structural executions and graphs of changes in the estimated indicators from experimental data were built on their numerical values, allowing to evaluate the technical and economic efficiency for various designs of bulldozer blades.Discussion and conclusion. The analysis of the estimated indicators: material consumption G/Gпр and G/P show, that with the improvement of the blade design (cutting off the two lateral upper parts of the blade and adding the two lower side – extension knives), the metal intensity decreases, and the volume of the maximum set of drawing prisms increases, respectively, the productivity of the bulldozer increases; energy intensities, N/П, N/Gпр and G∙N/P2 show, that with the improvement of the design of the bulldozer blade, energy performance improves, i.e. the energy consumption spent on the development of a single volume of soil decreases; the specific force per unit width of the R/B knife and the specific power per unit width of the N/B knife are reduced. Generalized power savings and power loads R · N/B2 shows that, with the improvement of the blade design, their values almost do not change (the blade of the type design and the blades with equipment - a protruding middle knife and side scarves sharply (jumpingly) increase the volume of the prism drawing.
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