Vol 85, No 1 (2018)

Articles

The substantiation of parameters of sowing machine with adaptive dosing elements for seeding of corn

Dubina K.P., Nesmiyan A.Y., Dolzhikov V.V., Ashitko A.A.

Abstract

For sowing of corn precision seeders are used, one of the most complex and responsible details of which is a sowing machine. The purpose of this study is to substantiate the rational design and parameters of the dosing elements and the «superfluous» seeds seeder of the vacuum sowing device, which ensure an even increase in the supply of corn seeds to the furrow. A vacuum sowing machine is proposed for use in production, in which elongated suction holes are made on the sowing disk in such a way that their long axes are oriented to a radial direction at α angle. In addition, in the design of the sowing apparatus, the thickness of the first three projections of seeder for «superfluous» seeds is proposed to be made stepwise. Experiments carried out on the matrix of the orthogonal plan of the second order showed that the following parameters and tuning regimes of such a machine are rational for sowing corn seeds: width of suction holes tдэ = 3 mm; the smallest slot width in the vacuum chamber liner t = 3,0...3,5 mm; exhaustion in the vacuum chamber H = 5 kPa; thickness of the input edge of the working part of the “superfluous” seeds seeder h = 1,5 mm; angle of deviation of the longitudinal axes of the suction holes of the sowing disc from the radial direction α = 12...15 deg. Under laboratory conditions the machine provided the frequency of single seed feeds p1 = 99,0...99,5 %, which is close to the technological optimum. At the same time, the quality of seed dosing remained stable even with a significant increase in the angular velocity of the sowing disk.
Tractors and Agricultural Machinery. 2018;85(1):3-8
pages 3-8 views

Increase in the level of functioning of agricultural tillage machines by justifying the parameters of the column of the working body

Kambulov S.I., Rykov V.B., Bozhko I.V., Kolesnik V.V.

Abstract

The working bodies of tillers perform the most important role from the point of view of the technological process of tillage, as they provide all the parameters of its application. The purpose of the study is the justification of the parameters of the column of the working body of the tiller machine. The traction resistance as the main parameter of the working element is affected by the shape of lateral profile and cross-section of the column. In general, in the cross section, the columns of the working bodies can have: a plane with rectilinear boundaries, a plane with curvilinear convex boundaries, or a plane with curvilinear concave boundaries. The compacted core of the soil in front of the stand is not formed when the grinding angle is not more than 50°. In all other cases, such a nucleus is formed even at asymmetric sharpening angles. Consequently, the necessary condition for the shape of the cross section of the column should be the observance of the value of mentioned angle. The cross-section of the column (Folium of Descartes) meets the requirements imposed on it, as the sharpening angle does not exceed 50°, which does not contribute to the formation of the compaction core, and the boundary has the shape of a convex line, which ensures a minimum absolute speed, on soil movement. The column of the working body of the tiller machine should have the shape of a lateral profile close to the logarithmic curve, which reduces the energy intensity of the process by 20 ... 45 %, and in the cross section of the column there must be a plane bounded by arcs of the ellipse and tangent to these arcs drawn so that the angle at the top of the ellipse did not exceed 50°. This reduces the traction resistance of the column by 40 ... 52 %.
Tractors and Agricultural Machinery. 2018;85(1):9-16
pages 9-16 views

Analysis of qualitative indicators of the operation of combine harvesters with various designs of threshing-separating devices

Maslov G.G., Martynov B.Y., Belyaev A.V.

Abstract

The results of research on the qualitative performance of three types of combine harvesters with various designs of threshing-separating devices: the slashing type (Don-1500B), the slashing type with the accelerator (Tucano 480) and the rotor type (TORUM-740) are analyzed. The aim of the research is to reveal the best design of threshing-separating devices, which ensures the increase of combine productivity, quality of work, reduction of costs and crop losses. The urgency of the task under current market conditions is determined by the decrease in demand for Russian grain, which is sold abroad at the level of 4-5 class, and also by the need to reduce costs for the technological process and crop losses. During the research, theoretical and experimental methods were used, based on the application of the main provisions of the theory of agricultural machines and measurement methods, regulated by specific documentation. The results of theoretical studies on the determination of the dependence of the loss of the grain yield of winter wheat on the productivity of the combine harvester TORUM-740 per hour of the main time are presented. The cost of indirect losses of harvest (from macro- and micro damage to the grain of winter wheat of Olkhon type) is substantiated by various designs of threshing-separating devices. The results of laboratory studies of technological qualities of grain are presented: vitreousness, protein and raw gluten content after harvest ripening, as well as seed germination. The results of tests of combines on specific performance indicators, fuel consumption, energy intensity and grain cost are presented. It is concluded that from the self-propelled combine harvesters used in harvesting winter wheat of Olkhon type of Krasnodar Research Institute of Agriculture named after P. Lukyanenko the best operational and economic parameters and technological properties of the received grain were ensured by TORUM-740 combine.
Tractors and Agricultural Machinery. 2018;85(1):17-20
pages 17-20 views

Comparative analysis of microvave frequency devices for grain disinfection

Pakhomov A.I.

Abstract

To date, the main method of combating the contamination of grain and seeds in agriculture is chemical etching. Its essence lies in applying to the surface of seeds chemically active substances that destroy the parasitic microflora. However, the chemical method of sterilization is not without serious shortcomings. It is known that the most effective disinfectants - systemic fungicides - are poisonous, including for humans. The use of such substances in addition to toxicological effects contributes to the development of resistance of parasitic microorganisms, their mutations in the direction of extremely dangerous and resistant species. To avoid this, alternative methods and equipment are needed. Electrophysical effects, in particular, microwave frequency energy. At the same time, the mechanism for suppressing the parasitic microflora is fundamentally different and consists in the influence of biological organisms on the internal natural environment of biological organisms. In this environment, all the cellular processes of living organisms occur, therefore, changing its parameters, accompanied by the formation of active ions, is critical for the vital activity of parasitic microorganisms. For the ionization process to produce a significant effect, certain characteristics of microwave radiation are needed: power, duration, uniformity of supply to the material, which depends on the equipment used. The article formulates the basic requirements for decontaminating microwave equipment that can be effectively used in agriculture. The most important parameters of existing microwave devices are considered. For comparative evaluation, an almost convenient criterion is proposed - the decontamination efficiency factor, which takes into account the most important characteristics of the equipment in question in one digit. The calculation of the newly introduced coefficient for a number of microwave devices has been performed and its graphical interpretation is given. It is shown that the innovative installation SIGMA-1, developed at the Agrarian Science Center Donskoy, surpasses the analogues in terms of the decontamination efficiency factor of 1,5...3 times. Its advantages also include the possibility of further improvement by increasing the number of waveguide sections, which multiplies the productivity.
Tractors and Agricultural Machinery. 2018;85(1):21-26
pages 21-26 views

The method for calculating the traction resistance of a flat disk

Akimov A.P., Konstantinov Y.V.

Abstract

Scuffler with flat discs are widely used in areas, which are subject to wind erosion of soils, to cover moisture on the stubble fields. Flat discs do not wrap the layers they remove, but only loosen them, shifting them aside. It is preferable to use such scrapers during presowing tillage and on steam, since in this case there is less sputtering of the soil, and its lower (moist) layers are not carried to the surface. Therefore, many industrially manufactured scufflers are equipped with flat discs, and the task of constructing a mathematical model for the interaction of such discs with soil is topical. Many mathematical models of the disc-soil interaction, taking into account the distribution of soil reaction forces on the disk, have been proposed, but all these models were constructed assuming that the disk is moving in its plane. Therefore, they are not applicable to the disk of a lakeshield moving with a non-zero angle of attack in the soil. The purpose of this work is to construct a mathematical model that allows calculating the traction resistance of a disk moving with a given angle of attack. The basic assumptions made in the construction of this model: the speed of the translational movement of the disk and its depth are constant; friction in the disk bearing can be neglected; the soil pressure on the lateral surface of the disc and the force of the soil reactions per unit length of its blade can be replaced by their mean values. An explicit expression is obtained for the traction resistance of a disk of a scuffler moving with an angle of attack, depending on its relative depth, the angle of attack, and the empirical coefficients. The adequacy of the constructed mathematical model is confirmed by comparison with known experimental data. It makes it possible to significantly reduce the number of full-scale experiments on the study of the interaction of flat discs of a scuffler with the soil, replacing them with computational ones, and reasonably carry out power and strength calculations of such discs. In addition, it can be used to optimize the parameters of the flat discs of the scuffler.
Tractors and Agricultural Machinery. 2018;85(1):27-33
pages 27-33 views

The choice of a rational ballasting scheme and the angle of application of the traction force for a caterpillar tractor

Gorodetskiy K.I., Sharipov V.M., Alendeev E.M., Lavlinskiy A.M.

Abstract

A feature of the layout of modern tracked tractors is that the center of mass of the tractor is usually located with a forward shift from the center of the caterpillar support surface. Such a layout solution, in combination with the use of ballast weights placed most often in front of the tractor, makes it possible to provide its required traction and coupling properties when assembling with guns. However, since the tractor operates with a wide range of loads, when changing the gun with high traction resistance, for example, to a low-resistance trailer, it becomes necessary to adjust the weight of the ballast. In practice, this adjustment is often not carried out, i.e. Once installed, the front ballast is used throughout the operating life of the machine, worsening its fuel economy and not providing optimum traction and coupling properties. In this regard, the important task is to find solutions that would eliminate the need to adjust the mass of the ballast depending on the hook load. For this purpose, the article deals with the scheme of ballasting of a caterpillar tractor with the application of traction force at a positive angle. Also, for the Challenger MT865B tractor, with a number of assumptions about its geometric parameters, the calculated dependence of the ballasting coefficient on the coupling weight and the thrust angle was constructed. Dependence analysis allowed to come to the conclusion that it is possible to ensure the coincidence of the pressure center with the middle of the tractor's support surface over the entire range of its loads, with constant values of the ballasting factor and the angle of application of the traction force. To calculate the optimal values of these parameters, the paper presents the corresponding formulas.
Tractors and Agricultural Machinery. 2018;85(1):34-39
pages 34-39 views

The unification of certain terms and concepts used in the study of land transport-technological vehicles

Parfenov A.P., Shchetinin Y.S.

Abstract

On the basis of the analysis of terminology used in textbooks, monographs and articles, related to the theory, design and calculation of automobiles, tractors, wheeled and caterpillar transport and traction machines, the uniform terms and concepts are proposed, the most frequently used in the above mentioned disciplines and related technical documents to describe similar phenomena or processes. The coefficient of traction, tractive force on the surface adhesion, the vehicle adhesive weight, the coefficient of adhesive weight, the specific tractive force, the specific hook load, the coefficient of resistance to the rectilinear motion of the machine, the road surface resistance coefficient, the tractive force of the machine, the free engine power, the engine power losses associated with its maintenance, the parameter of rotation of the caterpillar tractor and the power factor of rotation are analyzed. In various literary sources, different terms are used to designate the same quantities, the same definitions are treated differently. It has been causing certain inconveniences and introduces confusion in the theory of land vehicles. The necessity for such unification is particularly relevant in relation to the approval of the Federal Education Standard in the speciality 23.05.01 «Land Transport-Technological Means», in which the above mentioned disciplines are included in the training of specialists, and the knowledge of the relevant technical terminology is considered at the level of competence. In this article, concrete proposals are given on the unification of certain terms and concepts used in the above mentioned theoretical disciplines. Since the field of terminology and definitions is rather painful and delicate, these proposals are submitted for a substantive discussion by professionals.
Tractors and Agricultural Machinery. 2018;85(1):40-46
pages 40-46 views

Force analysis of the mechanisms of tillage machines working elements following a specified path

Parkhomenko G.G., Parkhomenko S.G.

Abstract

During the soil tillage in the rows of perennial plantations, the working elements have to move in the transverse direction while traversing of the bole. The specified path of the working elements movement is determined by the required protective zone. The specified path of the working elements movement at minimum energy costs for the technological process of soil tillage implementation should be observed. The working elements movement is carried out by a four-bar linkage, controlled by a hydraulic drive. Energy costs depend on forced effort, applied to the driving link of mechanism and soil resistance forces, acting on the working elements in the form of distributed load. The forced effort is proportional to the created pressure in the hydraulic drive. The energy costs can be reduced by using soil resistance forces acting on the working elements. Under a certain ratio of the movement mechanism parameters, the working elements under the action of soil resistance forces, tend to a row of perennial plantations and are retained in it without the usage of the hydraulic drive. The aim of the investigation is to justify a method of reducing the energy costs for the implementation of the technological process of soil tillage by analyzing the mechanisms of the working elements movement. The crane mechanisms, trapezoidal, parallelogram, cultivator H-7 of «Holder» company, movements of the left-handed, right-handed and symmetrical working elements were subjected to the research. A reduction in energy consumption is possible when moving the trapezoidal mechanism of the left-handed or right-handed, as well as the symmetrical working elements. Other mechanisms are characterized by additional energy costs as well. The main part of the energy is spent for retraction by means of hydraulic drive of working elements from a number of plantations. The retraction of the left-handed or right-handed, as well as of the symmetrical working elements in a row is carried out under the action of soil resistance forces by a trapezoidal mechanism with the ratio of the links 1:0,448:0,325:0,896:1,563.
Tractors and Agricultural Machinery. 2018;85(1):47-54
pages 47-54 views

Classification and synthesis of three-loop planetary gearboxes

Salamandra K.B.

Abstract

In the transmissions of trucks, agricultural vehicles and tractors, gear boxes with a planetary divider and/or an additional reductor unit which is depending on the traffic conditions of the machine, reduces the speed of rotation or operates on a direct drive are used. The divider and the additional reductor unit are intended for a stepwise changing of the range of the main 3-speed or 4-speed gearbox, consisting of gears with fixed axles, which makes it possible to increase the number of stages realized 4 times. If the planetary train will work in the differential mode, this will allow additionally increase the number of stages in the combined planetary gearboxes and, accordingly, the number of operating modes of the tractor. Consequently, the main gearbox consists of gears with fixed axes of gears can work either separately in a single-flow mode of operation of the planetary train (reductor or in the direct drive mode) or in a two-flow mode - in parallel with other ordinary gears when the planetary train as a differential. When using two planetary trains operating in the differential mode, the number of parallel power flows increases to three, which makes it possible to further improve the functional and power capabilities of multi-flow gearboxes. The purpose of the study is to analyze gearbox schemes consisting of three sets of gears with fixed gearwheel axes and two differential mechanisms forming three parallel power transmission flows. Classification of possible structural schemes of three-flow transmissions is given, a general expression for calculating the number of stages of a three-flow gearbox is obtained. A technique for the synthesis of kinematic schemes of three-flow planetary gearboxes is described, with the using of which new gearbox schemes are obtained for each possible structure, which are characterized by using simple mechanisms, high efficiency and a small number of control elements.
Tractors and Agricultural Machinery. 2018;85(1):55-67
pages 55-67 views

Probabilistic-statistical method for determining ergonomic tolerances of machine-tractor units with a gas-turbine engine

Shkrabak V.S., Dzhabborov N.I.

Abstract

The justification and usage of tolerances for ergonomic parameters ensure safety and improve the conditions and safety of operators of machine-tractor units. The subject of the investigation is a development of the mathematical models for a determination of the ergonomic parameters of machine-tractor units with gas-turbine engines. The aim of the investigations is a development of the probabilistic-statistical method for a determination of the ergonomic tolerances of machine-tractor units equipped with gas turbine engines. The novelty of the researches consists in the developed mathematical models and algorithm for a calculation of the tolerances for ergonomic parameters of machine-tractor units with gas-turbine engines. The proposed method is developed on the basis of systems analysis and methods of collecting and processing information, mathematical modeling. At the same time, state standards GOST 26387-8, GOST R ISO 15005-2012, GOST R ISO 15534-1-2009 were also used. Ergonomic parameters of machine-tractor units are divided into the following basic groups: anthropometric, hygienic, physiological and psychological. As the main quantitative characteristics of the tolerances for ergonomic parameters of machine-tractor units, the following are defined: adjusting tolerances for the level of adjustment, adjusting tolerances for the accuracy of adjustment and control tolerances. The proposed method and algorithm for a calculation allow to predict the optimal values of ergonomic tolerances of machine-tractor units with a probability of 0,95. As an example in the article, the examples of calculating the temperature tolerances at the mechanic workplace of the machine-tractor unit with a gas-turbine engine GTD-350T are given. It is established that the optimum values of the adjusting tolerance for the level of the temperature setting at the mechanic workplace are equal to 20±1 °C, and the adjusting tolerance for the accuracy of the adjustment is ±0,7 °C. The established ergonomic tolerances and the probabilistic-statistical method for their determination are intended for a justification, continuous control and ergonomic parameters assessments that ensure the safety and improvement of the conditions and labor protection of the operator of machine-tractor units with a gas turbine engine. The proposed probabilistic-statistical method provides the definition and optimization of ergonomic parameters of machine-tractor units with a gas turbine engine, taking into account the probabilistic character of their changes under specific conditions of their operation.
Tractors and Agricultural Machinery. 2018;85(1):68-73
pages 68-73 views

The influence of modifiers on the conservation of rubber products of agricultural machinery

Mel'kumova T.V.

Abstract

The purpose of the research is to determine the efficiency of various modifiers for increasing the re-sistance of rubber products to the effects of ozone contained in the air, under a long-term storage of agri-cultural machinery in open areas during the off-season. The task of the research is to determine the pro-tective properties of rubber modifiers under the conditions of the destructive effect of ozone. Experimental investigations were carried out in the ozone chamber OMS-1 using standard techniques. Ozone aging was carried out consistently in three stages respectively with stretching samples at 20, 30, 50 %, the duration of each stage of the experiment - 6 hours. After each stage of the tests, visual inspection of the samples was carried out. The ability of a deformed sample to resist the destructive effect of ozone was determined by the time of appearance of the first cracks visible to the naked eye on the surface of the sample. The results of the data obtained during the experiment showed that the introduction of the modifiers «Stillage bottoms of telomeric alcohols» and «Fluorine paraffins» into the rubber of the brand NO-68-1B-1 (from BNKS-18A rubber) already at the first stage of testing leads to the appearance of a continuous mesh small cracks on the samples surface. On samples from this rubber, subjected to surface fluoridation at the last stage of the test, a number of edge cracks up to 11 mm in length and up to 1 mm deep are appeared. On samples from the rubber of grade 26-82-4 (from SKEPT-50 rubber), the pointed cracks appear on rubber samples, and the modification of this rubber with the composition «Stillage bottoms of telomeric alcohols» accelerates this process. The experimental samples of rubber IR-5-1, as modified and as subjected to surface fluorination, have withstood the ozone aging test without traces of destruction. The results of the conducted studies allow us to conclude that it is necessary to develop new protective compositions that exclude the destruction of rubber technical products of agricultural machinery during long-term storage in open areas.
Tractors and Agricultural Machinery. 2018;85(1):74-79
pages 74-79 views


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