No 2 (2018)

Articles

Gimazetdinov R.R., Malozemov A.A., Kukis V.S. Diesel-generator plant with the recovery of waste heat of the piston engine

Gimazetdinov R.R., Malozemov A.A., Kukis V.S.

Abstract

The subject of the investigation was the waste heat recovery system of a small-scale heat electropower station that can be used as stationary and primary, reserve or additional source of electrical and thermal energy. The object of the investigation was the waste heat recovery system of the diesel engine D 180 and the small-scale heat electropower station on the basis of the diesel generator plant DGU-100C produced by JSC «ChTZ». The aim of the investigation was an experimental estimation of the efficient use of the diesel engine’s waste heat recovery system. The recovery system was consisted of an original heat exchanger for the recovery of the waste heat of the diesel engine’s cooling system, the waste heat of the lubricating system, the centers of which is made in a common housing, and the heat exchanger for the recovery of the exhaust gases waste heat from the diesel engine (pre-heater boiler PZD-600). The article presents the small-scale heat electropower station’s arrangement with the waste heat recovery system, the original heat exchanger arrangement and a scheme of the small-scale heat electropower station with the waste heat recovery system. The principle of operation of the proposed system is described. In comparison with the known constructions, in the proposed cogeneration power plant there is no need to separately regulate the temperature of the cooling liquid and the lubricating oil at the inlet to the piston internal combustion engine and the necessity to use an additional liquid-oil heat exchanger or oil cooler in the operation of the cogeneration plant without thermal load. Collectively, it was ensured a reduction of the complexity, material consumption and overall dimensions of the recovery system and the cogeneration power plant in general. The absolute economic effect from the using of the waste heat recovery system is 240…300 thousand rubles for the engine life, specific - 22…28 rubles/h. The payback period of the waste heat recovery system is less than a year. The obtained results convincingly indicate the economic feasibility of implementing the proposed system of waste heat recovery of the diesel engine D 180 of a small-scale heat electropower station based on the DGU-100S.
Tractors and Agricultural Machinery. 2018;(2):3-7
pages 3-7 views

Comparative analysis of the consumer characteristics of needle and tooth harrows

Eremenko Y.V., Nesmiyan A.Y., Kulakov A.K., Asaturyan S.V.

Abstract

In modern agricultural production, especially in areas of insufficient moisture, needle harrows-hoes and tooth harrows are widely used. The purpose of these groups of tools are generally alike, however, there are separate functional features. Their knowledge, possession of objective information on consumer characteristics of these tools will allow to form more rational structure of Park of cars of the agricultural enterprises, to organize their effective operation and will promote further improvement of designs of tools. The aim of the present study is a generalized comparative analysis of operational and economic characteristics and agrotechnical performance of needle harrows-hoes and tooth harrows. To achieve this goal, the study collected information about the main operational and agrotechnical characteristics of tooth harrows and harrow-hoes that were tested at the machine-testing stations of our country. The analysis of the obtained results allowed to conclude that the use of needle harrows in comparison with tooth harrows provides an increase in the productivity of aggregates by an average of 13...20 %, a decrease in the field surface crests by 15 % (3 mm), an increase in soil crumbling by 7 %. In equal conditions harrows-hoes damage 3...7 times less cultivated plants than tooth harrows. The fuel consumption and the uneven depth of tillage aggregates with a needle and Zubov harrows provided approximately the same performance. At the same time harrows hoes 1,83 times more metal than tooth and more labor-intensive in service. In General, it can be concluded that the performance characteristics and agrotechnical performance of needle harrows are higher than the ones, however, economic-lower.
Tractors and Agricultural Machinery. 2018;(2):8-12
pages 8-12 views

The working body for the application of mineral fertilizers

Ovchinnikov V.A., Ovchinnikova A.V.

Abstract

Currently, for the surface application of fertilizers, both in Europe as well as in Russia, spreader devices of various designs and arrangements are used. The metering devices in them, as a rule, are centrifugal type disk mechanisms with a vertical axis of rotation. Overview and analysis of their work shows that they do not completely meet the agrotechnical requirements, namely, distribute fertilizers on the soil surface with significant deviations from the permissible unevenness. Therefore, the development of a working body for increasing the uniformity of the distribution of mineral fertilizers over the field surface is an urgent challenge. The uniformity of the distribution of mineral fertilizers by a centrifugal working body is based on the difference in the speeds of fertilizer’s granules at the moment of their descent from the working body. The magnitude of the velocity affects the range of flight of particles (the coverage) and depends on the structural and kinematic parameters of the working body. At the department of agricultural machines of the Mordovia State University a centrifugal working body has been developed, at any point of which the descent of mineral fertilizer’s granules proceeding at different speeds. That had been achieved through the the fact that the working body contains a conical surface, along the generatrix of which, blades of different lengths are rigidly fastened. When working, the fertilizers are fed to the conical part and are distributed in a uniform layer and continue directed movement along the conical surface. The circumferential velocity of the working surface towards the base increases, and consequently the velocity of particle descent from different points of the working surface increases. The rest of the fertilizers flows continuously to the spherical disk and is directed to the soil surface by the blades. From blades of different lengths, fertilizers come off at different heights, at different angles of inclination to the horizon and at different speeds, which will affect the uniformity of their application. The results of the investigations are showed that the use of the experimental working body allows to increase the working width from 10 to 14 m and to reduce the uneven distribution of mineral fertilizers over the total width by 14,2 %.
Tractors and Agricultural Machinery. 2018;(2):13-16
pages 13-16 views

Creating a domestic caterpillar tractor for modern agricultural production

Sharipov V.M., Izmaylov A.Y., Dorokhov A.S., Fedotkin R.S., Kryuchkov V.A., Esenovskiy-Lashkov M.Y., Ovchinnikov E.V.

Abstract

The generated deficit in the last decades of universal tractors and tractors for the arable farming which belongs to the class 2…3, produced during the times of the USSR in the countries of the Council for Mutual Economic Assistance, as well as the problems of agricultural production created conditions for intensive expansion by foreign companies which are actively conquering the domestic market. However, the foreign samples have a high cost with a low adaptation to the conditions of the regions of the Russian Federation and the lack of proper service maintenance. The question of the necessity to create the domestic universal caterpillar tractor was raised in the article, and the prerequisites for its creation are propounded. The necessity to expand the scope of application the tractor was discussed. The tractor’s potential competitive advantages in comparison with foreign analogues are pointed out, including the aggregation with a wide range of machines and implements, adjustable track, the ability to move along the different types of roads, improved maneuverability, economy and environmental friendliness, the possibility of stepless speed regulation and etc. The assumed technical solutions for the main units and systems of the tractor are described, including a power unit with an adaptation system for operation on liquefied hydrocarbon gas; transmission, containing a full-flow hydrostatic transmission or a double-flow hydrovolume-mechanical transmission with the drive to each side, as well as the drive of power takeoff shafts (front, rear and side); frame; all-season ecologically safe caterpillar chassis with rubber-reinforced tracks and elements of the caterpillar track on the basis of polymer-composite materials; a modern and comfortable cabin with a steering column. The prospective indicators of economic efficiency from the application of the tractor, as well as the prospects of further equipping the tractor with remote and autonomous control systems are pointed out.
Tractors and Agricultural Machinery. 2018;(2):17-25
pages 17-25 views

Selection of accelerated test modes for the head of cylinder of the automobile diesel engine

Gots A.N., Klevtsov V.S.

Abstract

The possibilities of a prediction of the heads of cylinder durability of the automotive diesel engines at the design stage and their completion to specified parameters, especially for reliability are considered. Since diesel engines operate in the unsteady modes, the main load is not only mechanical, but also thermal. At that, it occurs when the operating modes of the diesel engine change. The most loaded sections in the cylinder head are the bridges between the inlet and exhaust valves, as well as the bridges between the nozzle holes and inlet and exhaust valves. Under the influence of the thermal load, the distortions of the crystal lattice appear in the sections of the cylinder head at first, which leads to the appearance in some direction in which the greatest tangential stresses act, tears, gradually change under the influence of alternating stresses in the crack. When the total accumulated damage reaches a certain critical value, and the crack substantially weakens the cross section, fatigue failure occurs. To ensure the reliability of the diesel engine in operation, it is necessary to choose such methods of calculation and testing that would ensure a specified durability of the cylinder head. Since the reliability check in operation takes considerable time, that accelerated testing is used to reduce the test time. The place occupied by the accelerated tests in the design of diesel engines, as well as the sequence of the formation of their program are considered. It is shown that in practice it is possible to achieve only a certain degree of change in the technical condition of the cylinder head due to the degree of completeness of the accounting of the interacting operational loads and their distortion during reproduced on the test equipment. Possible modes of testing the cylinder heads on a non-motorized thermal bench are proposed with the aim of a determination their durability. They correspond to the modes of accelerated tests for the reliability of the automobile diesel engines. The problem of convergence of the results at accelerated tests and the data under operating conditions is considered.
Tractors and Agricultural Machinery. 2018;(2):26-33
pages 26-33 views

Automatic control of the movement of the caterpillar vehicle with intelligent hydrostatic transmission for target designation in GPS coordinates

Kondakov S.V., Dubrovskiy N.V.

Abstract

The article is devoted to algorithmizing the control of an autonomous vehicle by the example of the caterpillar vehicle with an onboard hydrostatic transmission. The authors developed a mathematical model which has scientific novelty, obtained the results of an analytical solution and a physical experiment that confirmed the reliability of the model and the operability of the proposed algorithm for tractor control in the automatic mode in the global positioning coordinates. The model takes into account the features of the hidostatic drive, made on-board, including mechanical and volume losses. A characteristic feature of the mathematical model is the differential equations for the industrial logic controller and the control mechanism for the inclined washer of the axial-piston adjustable hydrostatic transmission pump and the algebraic equations for conversion of the Cartesian coordinates to the global positioning coordinates. The mathematical model is implemented in the VISSIM programming environment. The object of the investigation is the industrial tractor TM-10 with hydrostatic transmission which is produced by the plant «DST-Ural» in Chelyabinsk. The physical experiment was carried out on the experimental model and showed satisfactory results. The developed algorithm is implemented in the CoDeSys environment for an industrial controller that controls the movement of production tractors. The extended mathematical model allows to assess more accurately of transient processes of the motion in the automatic mode. The formation of the control action via GPS coordinates provides new possibilities during solving the task of positioning the caterpillar vehicle in the open area. The developed algorithm allows to estimate the time which is spent on the formation of commands by microprocessor devices. The conducted investigations allowed to form new consumer properties to the industrial tractor of the plant «DST-Ural», consisting in the appeared possibility of using tractors without an operator in harmful or dangerous conditions for humans.
Tractors and Agricultural Machinery. 2018;(2):34-40
pages 34-40 views

Optimization of design parameters of radial tires of propellers of combine harvesters

Melikov I.M.

Abstract

The article is devoted to the solution of an important scientific and practical problem - optimization of the tire shell design parameters of the leading wheels of combine harvesters of high productivity, operating in conditions with low bearing capacity. Optimization of the parameters of the pneumatic tire, as a link in the oscillatory system and the main element of the wheel propulsion, is one of the directions for improving the functioning of combine harvesters. One of the factors affecting the performance indicators of combine harvesters is the perfection of wheeled propellers. Their agrotechnical properties can be improved due to a rational choice of tire parameters depending on the type of rolling surface, which will also help to reduce fuel consumption. On the basis of the abovementioned, the aim of this paper is to investigate the effect on the performance of combine harvesters of the characteristics of the tires used on the driving wheels and to improve their agrotechnical properties by optimizing the parameters of the pneumatic tires. The description, methods and results of experimental studies using specially designed and providing reliable results of devices for determining deformations of the inner and outer shells of the tire relative to the rim in the circumferential and radial directions, as well as contact pressures and stresses in the soil are described. On the basis of theoretical and experimental studies of the work of combine harvesters of high productivity, the influence of the parameters of the pneumatic tires of the driving wheels on the performance of them has been established. The optimum combination of design parameters of the experimental pneumatic tire of a radial design for grain harvesters is determined. The results of the research will make it possible to develop recommendations for the selection of optimal parameters for pneumatic tires that contribute to improving the performance of grain harvesters used under various operating conditions by bundling their driving wheels with radial-type tires.
Tractors and Agricultural Machinery. 2018;(2):41-46
pages 41-46 views

Optimization of the reinforcing layer of the compressor wheel from the composite material of the diesel turbocharger

Netrusov A.N., Fomin V.M.

Abstract

The purpose of this paper is to search for the optimal configuration of the variable parameters of the reinforcing layer of a compressor wheel made of a composite material. The composite material considered in this paper is a carbon matrix filled with carbon fiber. Variable parameters were the fiber fraction in the composite, the total thickness of the reinforcing layer, and the fiber fraction in the composite oriented in the circumferential direction of the disk. The objective function in this study is the safety factor of the wheel. The parameters were optimized by the Gauss-Seidel method. At each optimization step, the problem of the theory of thermoelasticity of anisotropic media was solved by the finite element method. In the course of the study it was found that the maximum safety factor of the wheel 1,15 is achieved with the maximum fiber fraction in the composite, the thickness of the reinforcing layer 1,4 mm and the fiber fraction 0,581 oriented in the circumferential direction. The deformations of the wheel with the above parameters remain at an acceptable level. According to the results of calculations it is established that it is possible to increase the level of manufacturability of the impeller production due to the transition to the reinforcement of the disk only in the circumferential direction. At the same time, the reduction of the general safety factor will be less than 6 %. Proceeding from the results obtained during the optimization process, it follows that in the future the optimization problem for the component base considered in the work can be carried out only with respect to the fiber fraction oriented in the circumferential direction. In the final part of the work, an analysis of the mass-inertial characteristics of a composite wheel with a wheel produced using traditional technology was made. The mass and moment of inertia of the rotor in the case of a wheel from composite material will be reduced by 11 % and 18 %, respectively.
Tractors and Agricultural Machinery. 2018;(2):47-53
pages 47-53 views

Preliminary results of the study of the effect of a multi-cycle load on the hardness of a high-pressure fuel pipe

Sveshchinskiy V.O., Bobrov S.P., Tereshchenko I.S.

Abstract

Investigation of the effect of internal pressure on the distribution of hardness in the fuel pipe wall was conducted. In the high pressure circuits of Common Rail systems, the fuel pressure is much higher than the pressure level in conventional fuel systems. Thas is why it is of practical interest to change the mechanical properties of the component materials during operation. In the present work, an attempt was made to evaluate the influence of the multi-cycle loading of the fuel pipe with a high internal pressure on the hardness of the material from which the fuel line was made. The loading was carried out under the conditions of a non-motorized test bench with a pressure of diesel fuel of 160 MPa. The test duration was 500 hours. With the selected pump shaft speed and the response frequency of the electrohydraulic control valves this was equivalent to approximately 96x106 cycles. Before and after the tests, hardness measurements were made in the cross section of the fuel lines. The distributions of hardness values are obtained, which testify the existence, under the given loading conditions of a self-hardening process of the material. In the initial state, fuel lines are characterized by a certain anisotropy of hardness and, accordingly, strength characteristics. In this case, the inhomogeneity of the field of values of hardness decreases with decreasing radius of location of the material layer. Dispersion of hardness values takes place both along the axis of the fuel pipe and in the circumferential direction. Loading of fuel pipes of the Common Rail type with pulsating hydraulic pressure leads to a redistribution of the hardness values in the fuel pipe wall. It is found that in the layers of material located closer to the central channel of the fuel pipe, the hardness equalization occurs to a greater extent as it is used, than in layers located far from the central channel. In general, the hardness is increased, which can be interpreted as the hardening of the fuel line during operation.
Tractors and Agricultural Machinery. 2018;(2):54-58
pages 54-58 views

Substantiation of constructive and technological parameters of a cylindrical cleaner of soil impurities of onion harvester

Sibirev A.V., Dorokhov A.S., Aksenov A.G.

Abstract

A special feature of harvesting onion is that the composition of the impurities of the onion-soil heap coming from digging up to the separating working organs is soil lumps commensurate in size with onion bulbs, which are difficult to separate into slit (bar elevators, screens) working organs. Secondary separation of onion on the most common secondary separation devices - pinholes - is restrained by the heterogeneity of the mechanical properties of the harvested onions. In well-ripened onions with dead tops the roll-off angles are clearly separated from the rolling-off angles of plant and small soil impurities, but when the undersized tops are separated, it is difficult to separate bulbs and impurities from the paltry hill. The separation of root crops and onions from impurities in mechanical separators is based on the physico-mechanical properties of the interacting products: friction coefficients, surface shape factors, speed recovery coefficients, mass, density and strength characteristics. This circumstance is caused by the fact that the excretion of soil lumps on the slit working bodies (rod conveyors and screens) occurs according to dimensional features and this does not lead to the solution of the existing problem: the separation of soil lumps commensurate in size with onion bulbs. The article presents the design of a cylindrical soil purifier that ensures the maximum completeness of separation of a heap of onions from soil impurities, including from commensurate soil lumps. The results of theoretical studies of a cylindrical soil purifier on the substantiation of structural and process parameters during the separation of onion-seed heap from soil impurities are presented.
Tractors and Agricultural Machinery. 2018;(2):59-64
pages 59-64 views

Method and results of the evaluation of the influence of the energy of grain recovery, contacting in the head with header fairing on its parameters and quality of work

Bur’yanov A.I., Bur’yanov M.A., Chervyakov I.V.

Abstract

When harvesting grain crops with combine with combining fairing, the process of contact of plants with its fairing includes the impact of the head of the plant on the surface of the fairing, and movement along its surface. The greatest probability of loss of those head grains that contact through the scales covering them with the fairing of the header was analyzed. The type of impact of these grains depends on the shape of the fairing and the angle of inclination of the plant. At the direct impact of the speed before and after impact are proportional to the recovery factor and can be sent in the forward or reverse direction. If the impact is oblique and the deviation of the velocity vector is within the angle of friction the velocity after impact is determined on the basis of Newton's dry friction hypothesis. In grain crops, a stalk is of low stiffness, and, according to our data, compensates for the damping properties of the grain covering the scales. When the head strikes, the grains acquire the kinetic energy expended on the deformation of the contacting surfaces (the lost energy) and the energy of recovery. The loss of grain will occur if the energy of grain recovery is greater than the energy required for its separation. The purpose of the research, the determination of the energy released during the restoration of the head grains, contacting through the scales covering them with the header fairing. The method was tested by comparing the renewal energy of the grain of winter wheat, which is insensitive to the contact of the head with the surface of the fairing made of steel and high-strength polymers. It is established that on the eighth day of harvesting, with a breadmaking humidity of 9-11 %, the work required to separate one grain from the head is reduced to 0,0015 J. Under these conditions, the harvesting unit equipped with a combing header with a fairing made of steel can work without loss of grain in the first phase of interaction with it at speeds up to 2,3 m/s, and with a header, the fairing of which is made of ultra-high molecular weight polyethylene, at speeds up to 3,5 m/s.
Tractors and Agricultural Machinery. 2018;(2):65-72
pages 65-72 views

Development of elements of technology for increasing the durability of tractor components from gray cast iron

Ovsyannikov V.E., Vasil’ev V.I., Terekhov A.S.

Abstract

The problems of increasing the durability of tractor parts from ferrite-pearlitic gray iron by using the process of diffusion surface doping with subsequent quenching for martensite are considered. The process of diffusion surface doping of gray iron is realized by heating the alloy in contact with the oxide of alloying elements (chromium, titanium, vanadium, etc.). At the same time, dissociation of the oxide molecule of the alloying element and the diffusion of atoms into the interior of the cast iron occur on the alloy surface. This scheme of the process makes it possible to oxidize the carbon of the cast iron base and simultaneously alloy the surface layer. Studies of the diffusion layer have shown that it has a pearlite structure, which means that it is possible to use the quenching process to obtain a martensitic structure. Important factors that determine the resistance of metals and alloys to wear include their structure, physical and mechanical properties, as well as their mutual arrangement, the quantitative ratio and the nature of the relationship between the individual components of the structure of the material. An important issue in the practical implementation of the technology in is the determination of quenching regimes that provide the required microstructure and properties of the alloy, primarily the heating time for quenching. In this paper, we consider the possibility of applying heat engineering calculations to solve the abovementioned problem. Calculation of the heating parameters for quenching was carried out by solving the heat equation in the criterial form. The heating of a cylindrical part was considered. On the basis of the determination of the Bio and Fourier criteria, heating curves were constructed, which made it possible to determine the desired values of the heat treatment regimes. Experimental verification of the obtained results showed that the microstructure of the alloy is fine-needle martensite, which confirms the applicability of the calculated determination of the quenching regimes.
Tractors and Agricultural Machinery. 2018;(2):73-77
pages 73-77 views

Application of differentiated tillage

Fedorov S.E.

Abstract

The main indicator of the physical state of soils is the density of structure. When comparing the values of the equilibrium and optimal soil density for agricultural crops, the need of one or another mechanical treatment is determined. This suggests that at present the soil treatment system can not be uniform, universal, equally suitable and effective at different points in the field. It must be differentiated, adapted to soil and climatic conditions. Proceeding from the above, there appeared the idea of the need to create a combined cultivator for differentiated soil cultivation, which provided the desired predictable process of work under accomplished conditions. The purpose of the study is to reduce energy costs, improve the quality of surface preparation of the soil through the application of differentiated tillage without reducing yields. Field studies on determining density and hardness of the soil were carried out at a temperature of + 20 ± 2 °C at different depths (0 ... 10, 10 ... 20, 20 ... 30 and 30 ... 40 cm) and repeated 4 times for each depth to determine the average values of the amplitudes. The moisture content of the soil during the treatment varied from 20 % to 26 %. The limiting relative error in the measurement was 5 %. When examining the hardness and density of the soil, one point (as one dimension) was laid on 4 ... 5 hectare. The results of the studies showed that the hardness and density of the soil in different points of the field are different. Over time their values increase. The minimum values of hardness and density were observed at a depth of 0 ... 10 cm and amounted to 8 kg/cm2 and 0,94 g/cm3, maximum at a depth of 30 ... 40 cm - 34,3 kg/cm2 and 1,41 g/cm3. In this direction, we proposed the creation of an experimental combined machine for differentiated soil cultivation, which automatically changes the depth of processing, depending on the density and hardness of the soil.
Tractors and Agricultural Machinery. 2018;(2):78-82
pages 78-82 views

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