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1
Janulevičius, Algirdas, Gediminas Pupinis, Justas Lukštas, Vidas Damanauskas e Vaclovas Kurkauskas. "DEPENDENCIES OF THE LEAD OF FRONT DRIVING WHEELS ON DIFFERENT TIRE DEFORMATIONS FOR A MFWD TRACTOR". Transport 32, n. 1 (13 luglio 2015): 23–31. http://dx.doi.org/10.3846/16484142.2015.1063084.
Testo completoAbstract (sommario):
Tractors are the main machines in agricultural production processes. Agricultural tractors commonly employ a four-wheel drive transmission. To reach maximum efficiency in production works, tractors are loaded by as high thrust as possible. The consequence of it, quite often, is that the slippage of driving wheels grows to the limit that is not allowed. To reduce the slippage, various ways are pointed out in terramechanics. One way is to increase the tractor’s weight by adding ballast. The other way is to increase the contact area between tires and the supporting surface. The slippage can be also reduced with traction control and other relevant systems. These methods, which help to reduce slippage, also affect tire deformation. When proportion of tires deformation is not the same as proportion of their sizes, the consequence is change of the lead of front wheels. In this paper analysis is presented, how the lead of front wheels affects the work of MFWD tractor in different conditions. Test results are presented for a MFWD tractor, how the lead of front wheels varies depending on deformation ratios between front and rear tires. For a MFWD tractor, values of deformation ratio between front and rear tires were determined, which ensured effective and which produced unreasonable values of lead of front wheels.
2
Rebrov, Oleksii. "BALLASTING AND DUAL TIRES USING OF WHEELED AGRICULTURAL TRACTORS UNDER THE CONDITIONS OF FULFILLING AGRO-ECOLOGICAL STANDARDS FOR SOIL INTERACTION". Bulletin of the National Technical University «KhPI». Series: Automobile and Tractor Construction, n. 2 (19 marzo 2023): 98–107. http://dx.doi.org/10.20998/2078-6840.2022.2.11.
Testo completoAbstract (sommario):
The article presents an analytical approach to the implementation of ballasting and dual tires using of agricultural wheeled tractors, which is based on the unconditional fulfilment of agro-ecological standards of tires soil interaction. The necessity of harmonizing the indicators of the position of the centre of gravity of the tractor, the footprint area of the front and rear tires ratio, as well as their load capacity is shown. The need to use equal flotation in tractor’s tires during single and double use has been proven, which determines the need to maintain the position of the centre of gravity during ballasting. The method of selecting the mass of ballast weights for installation in the rear wheel discs and the front linkage system of the tractor, as well as the ballast weight system, which makes it possible to ensure the maximum possible weight of the tractor to meet the agro-ecological requirements regarding the maximum pressure on the soil, is proposed. The perspective of dual tires using to reduce the maximum pressure of the tractor on the soil is shown, and the high efficiency of ballasting the tractor on dual tires is also proven. The example shows the possibility of increasing the part of the territory of Ukraine where it is possible to operate the tractor without violating agro-ecological norms by 20-40% due to the use of dual tires. The possibility of increasing the efficiency of the tractor up to 1.5 times due to ballasting and doubling of tires has also been proven. The obtained data are based on 20 calculation variants of the tractor with different degrees of ballasting and the use of different tire doubling schemes.
3
Rebrov, Oleksii, Boris Kalchenko, Maksym Yakunin, Volodymyr Makarov, Ihor Buchko, Olena Rebrova, Oleksandr Artiushenko e Alexander Leonenko. "EVALUATION ANALYSIS OF THE RUNNING SYSTEM SOIL INTERACTION OF WHEELED AGRICULTURAL TRACTORS". Bulletin of the National Technical University «KhPI». Series: Automobile and Tractor Construction, n. 1 (19 marzo 2023): 36–43. http://dx.doi.org/10.20998/2078-6840.2022.1.05.
Testo completoAbstract (sommario):
The article provides an evaluative analysis of the wheeled agricultural tractor’s running systems soil interaction. A sample of more than 600 MFWD tractors of the world's leading manufacturers was subject to analysis. To determine the parameters of the maximum soil pressure, the value of the footprint gross flat plate area is applied, assuming that the tires are operated under conditions characterized by the speed index A6 with a significant torque for a long time. It is obtained the calculated function of the probability distribution of the maximum pressure on the soil of a sample of modern wheeled tractors with a fixed location of the centre of gravity (weight distribution). The designed arrangement of the centre of gravity of tractors by groups with the corresponding rolling circumference indexes difference ΔRCI =4...9 was analysed. It was established that for general and universal purpose tractors with ΔRCI = 4...6 the most common weight distribution coefficient is 0.40 or 0.44. For special (utility) tractors with ΔRCI = 7...9, the most common weight distribution coefficient is 0.45...0.46. An analysis of the maximum soil pressure in a wide range of the traction force of the tractor while maintaining a constant optimal weight distribution, which depends on the ratio of the footprint gross flat plate area of the front and rear tires, was carried out. The analysis showed that maintaining a constant optimal weight distribution during traction operations makes it possible to reduce the maximum pressure on the soil by 8...40 kPa. This makes it possible to increase the part of the territory of Ukraine, where modern wheeled tractors with single tires can be operated without violating agro-ecological requirements, by 14%.
4
Akhmetov, Аdilbek, Sherzodbek Akhmedov e Javlonbek Ishchanov. "Investigating the Impact of Speed and Tire Pressure of a Wheel Tractor on Soil Properties: A Case Study in Northeastern Uzbekistan". AgriEngineering 6, n. 3 (3 luglio 2024): 2067–81. http://dx.doi.org/10.3390/agriengineering6030121.
Testo completoAbstract (sommario):
In agriculture, machines engaged in various agrotechnical activities and operations have different impacts on the soil. The effect of mechanization is primarily reflected in two indicators: soil density and hardness. At the same time, considering the direct dependence of tractive resistance on soil hardness in processing machines and sprayers, we studied subsequent changes in the soil in the path of wheels affected by the soil after the passage of four-wheeled and three-wheeled tractors. We also examined various atmospheric pressures in the tractor’s tires and the impact of different types of tires on soil compaction and traction. The studies showed that to reduce the compression impact on the soil of four-wheeled tractor working systems during certain technical operations, it is necessary to choose the maximum permissible travel speed and the minimum air pressure in the tires specified in the technical conditions. This approach helps to decrease soil compaction and maintain its structure. Additionally, it was found that three-wheeled tractors exert less pressure on the soil compared to four-wheeled ones, which should also be considered when selecting equipment for different agrotechnical tasks. Optimizing tire pressure and tractor speed is crucial for minimizing negative soil impact and enhancing the efficiency of agricultural operations.
5
Tukhtabayev, M. A., H. B. Atakhanov e O. A. Sidikov. "Influence of tire internal pressure on soil compaction". IOP Conference Series: Earth and Environmental Science 1231, n. 1 (1 agosto 2023): 012009. http://dx.doi.org/10.1088/1755-1315/1231/1/012009.
Testo completoAbstract (sommario):
Abstract The article presents the results of choosing tires for driving wheels of cotton-growing row-crop tractors during inter-row cultivation. The track surfaces of tires 15.5-38, 16.9R38, 420/85R38 and 18.4R38 are compared on a rigid base. The track surfaces for hard base and maximum pressure of tires on soil, soil density and tire tread depth were determined in experimental studies. When choosing tires, their average qav and maximum q max pressures on soil were determined. In order to reduce compaction impact of the tractor’s undercarriages on soil, impact force of the tire internal pressure and vertical load on soil are determined. When using with larger profile width of tires working between rows leads to crushing of seedlings, and the smaller profile leads to an increase in compaction effect on soil. By choosing the right tires and substantiating their parameters, the beneficial living organisms that increase soil fertility are not allowed to die. The tractor equipped with 18.4R38 tires was used with a wide width agricultural machinery in cotton field. As a result, the number of field crossings of the aggregate reduced by 1.87 times, soil compaction is prevented, and fuel consumption reduced by 25%.
6
Janulevičius, Algirdas, e Povilas Gurevičius. "IMPACT OF THE INFLATION PRESSURE OF THE TIRES ON LEAD OF FRONT DRIVE WHEELS AND MOVEMENT RESISTANCE FORCE OF TRACTORS". Transport 34, n. 6 (8 ottobre 2019): 628–38. http://dx.doi.org/10.3846/transport.2019.11233.
Testo completoAbstract (sommario):
The transmission of mechanical front-wheel drive tractors normally has a front axle lead ratio, which is equal to 1.5…2.5%. Naturally, when ballast masses are added to the tractor or when inflation pressure in the tires is reduced, distortion of the tires is inevitable, which changes the lead of the front wheels. In this paper, we present the impact of tire inflation pressures on the lead front drive wheels and movement resistance force when the tractor travelled with a front drive axle enabled and was engine braking with the fuel supply off. It was found that the variation in front and rear tires inflation pressure combination can significantly change the lead of the front drive wheels. For the tested tractor up to 6.9%. The result is that when the tractor travelled with the front axle enabled and was engine braking, the engine-braking efficiency decreases with increasing lead of the front wheels. Front (slipping) wheels create the opposite-direction torque, which is transferred to the rear wheels through the tractor’s front-rear axle drive system. Additional losses of the engine braking occur in transmission due to power circulation, and the result is that the tractor wheels receive less braking torque from the engine.
7
Katrenčík, Jakub, František Bauer e Petr Dostál. "The influence of the tire inflation on pull properties of agriculture tractors". Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, n. 6 (2013): 1733–39. http://dx.doi.org/10.11118/actaun201361061733.
Testo completoAbstract (sommario):
Agricultural tractors are robust and versatile machines, which must comply with the basic requirements of users under various conditions. The main requirements include economical and reliable operation and high performance. Fuel economy could be improved using multiple methods, for example a well trained operator, adequate farming conditions and optimal tire inflation. Tractor tires transmit engine power to the surface and as such they are crucial to tractor operation. In the first part of the field measurement, all tires were inflated to 180kPa, while in the second part of the field measurements the tire pressure was set to 75kPa in front tires and to 65 kPa in rear tires. The results of the field measurement of the John Deere 6920S tractor with different tire inflation shows that pull performance increased by 9.9% and wheel slip decreased by 9.7%.
8
Samorodov, V. B., A. Yu Rebrov e V. V. Kuchkov. "Increase of technical and economical parameters of wheeled tractors on the base of spatial and topologic approach". Traktory i sel hozmashiny 80, n. 7 (15 luglio 2013): 12–17. http://dx.doi.org/10.17816/0321-4443-65719.
Testo completoAbstract (sommario):
The spatial and topologic approach is considered as applied to solving the problem of increase of technical and economical parameters of wheeled tractors in conditions of variation of engine power, tires standard size, tractor mass and transmission gear ratio.
9
Zolotarevskaya, D. I. "Analysis of the influence of the main factors on the characteristics of the elastic properties of elastic wheels of tractors". Traktory i sel hozmashiny 85, n. 4 (15 agosto 2018): 71–78. http://dx.doi.org/10.17816/0321-4443-66415.
Testo completoAbstract (sommario):
The work is devoted to the theoretical study of the elastic properties of tractor wheels and the analysis of the effect of air pressure in the tires and vertical loads on the wheel axles. According to the developed computer program, which allows to implement the method of calculating the characteristics of the elastic properties of tractor wheels with pneumatic tires proposed in this work, one-factor and complete factor computer experiments of two types were carried out. In computer experiments of the first type, the dependences of the elasticity coefficients of a number of elastic wheels were investigated when operating on the practically non-deformable basis of tractors MTZ-82 and MTZ-142 from the air pressure in the tires at different values of the vertical dynamic loads on the axes of the corresponding wheels of tractors. In computer experiments of the second type, the dependences of the elasticity coefficients and the normal deflection of the wheels with tires of different sizes from the air pressure in the tires at constant values of the vertical dynamic loads on the wheel axles were investigated. In computer experiments of both types, the deviations of the elastic properties of elastic wheels found by calculation are within the limits of the accuracy of measurements of the experimental data. Based on the results of computer experiments of the first type, regression equations were obtained reflecting the dependence of the elasticity coefficients of the elastic wheels studied on the air pressure in the tire for various values of the vertical dynamic loads on the wheel axes. According to the results of computer experiments of the second type, equations of regression of the coefficients of elasticity and normal deflection of wheels with tires of different sizes from air pressure in tires at constant values of vertical dynamic loads on the wheel axle are obtained. The high correlation values for these regression equations indicate the high importance of the relationships in the found correlation dependencies. The application of the proposed calculation method makes it possible to simplify and shorten the work on the choice of tires of optimum sizes to different tractors, taking into account the specific conditions of their operation. It was calculated that wheels with tires 18.4R38 are optimal on the rear axle of the MTZ-82 tractor.
10
Kim, Wan-Soo, Yong-Joo Kim, Nam-Gyu Lee, Seung-Min Baek, Seung-Yun Baek e Yeon-Soo Kim. "Influence of Tire Contact Area on the Traction Performance of a 67-kW Agricultural Tractor in a Paddy Field". Journal of the ASABE 65, n. 6 (2022): 1421–32. http://dx.doi.org/10.13031/ja.15008.
Testo completoAbstract (sommario):
Highlights The tire contact area of a tractor was adjusted through a combination of four tires to improve the traction performance in a paddy field. Traction performance according to tire contact area was measured and evaluated through a traction load measurement system of the tractor. The increase in the tire contact area reduced the slip ratio of the tractor and led to high traction performance. The results of this study suggest the possibility of evaluating and improving the traction performance of a tractor by considering the tire contact area. Abstract. Agricultural tractors operate on soil, and power loss occurs due to the complex interaction between tractor tires and soil. There are various methods for minimizing the loss of power and driving the tractor efficiently, one of which is increasing the tire contact area (TCA). The aim of this study is to measure, evaluate, and optimize the traction performance of a tractor with different TCAs. A traction load measurement system of the tractor was developed to measure field data. Field experiments were conducted to measure the traction performance of the tractors on paddy fields. To improve the traction performance of the tractor, the TCA was increased through various tire combinations, and a total of four TCA conditions were used. The results showed that the slip ratio of the wheel decreased with increasing TCA, thereby reducing the power loss due to the soil and increasing the traction performance, including the traction force, traction power, tractive efficiency, and dynamic traction ratio. Therefore, it is possible to improve the performance of tractors in paddy fields through TCA adjustment, and this study can provide appropriate guidelines. Keywords: Agricultural tractor, Dynamic traction ratio, Tire contact area, Traction performance, Tractive efficiency.
11
M. A., Podrigalo, Artyomov M. P., Tretyak V. M., Krasnokutskyi V. M. e Omelchenko V. I. "Efficiency coefficient of tractor wheel drive while moving on ground". MECHANICS and AUTOMATICS of AGROINDUSTRIAL PRODUCTION, n. 1(116) (2023): 143–50. http://dx.doi.org/10.37204/2786-7775-2023-1-15.
Testo completoAbstract (sommario):
Purpose. The purpose of the study is to improve the energy efficiency of tractors when working on a deformable support surface by increasing the efficiency of the wheel drive due to the rational selection of its parameters. Methods. The methods of the theory of movement of traction vehicles and theoretical mechanics are used. Results. Analytical equations are compiled that describe the dependence of the interaction of wheels with pneumatic tires with the ground support surface. The effect of tangential soil compliance on the efficiency of a single wheel and wheel drive was determined, and the influence of soil compliance was taken into account to determine the rational distribution of torque (traction) moments between the driving axles of a two-axle tractor. Conclusions 1. As a result of the conducted research, the dependence of the coefficient of useful action of the tractor's wheel drive on the coefficient of distribution of torque (traction) moments between the axles during movement on a deformable support surface was determined. The resulting mathematical model takes into account both the circular stiffness of the tires of the driving wheels and the flexibility of the soil in the contact patch. 2. The rational (optimal with the adopted mathematical model) value of the torque distribution coefficient βm between the axles should vary depending on the rolling resistance of the driving wheels and the characteristics of the soil background. With an electric drive of the driving wheels, adjustment of the coefficient βm is possible, and with a mechanical drive of the driving wheels, control of the coefficient βm can be carried out by adjusting the ratio of torsional stiffnesses of the tires of the front and rear wheels due to their internal pressure. 3. For agricultural tractors it is advisable to adjust the air pressure in the tires for each bridge separately, depending on the type of running system(4K4a, 4K4b) and the physical condition of the soil. Keywords: wheel drive, two-axle tractor, coefficient of useful action, deformation of the support surface, traction moments.
12
Mamontov, Anatoliy, Yevhen Pelypenko, Olena Rebrova e Vadim Shevtsov. "DETERMINATION OF RATIONAL OPERATING MODES OF OPERATION OF TRACTOR AGRICULTURAL TIRES". Technology transfer: fundamental principles and innovative technical solutions 4 (30 novembre 2020): 36–38. http://dx.doi.org/10.21303/2585-6847.2020.001501.
Testo completoAbstract (sommario):
The efficiency of wheeled agricultural tractors when performing traction technological operations is characterized by two aspects. The first of these is traction efficiency, which mainly depends on the coupling weight of the tractor and the perfection of its running system. Another aspect is environmental friendliness, which is determined by the level of compaction impact on the soil. In general, these aspects are oppositely directed. That is, an increase in traction efficiency requires an increase in the grip weight and, as a consequence, an increase in the radial load on the tires and the internal pressure in them. This leads to an increase in tire pressure on the ground and deterioration in their environmental performance. As a result of excessive soil compaction, the yield of agricultural crops is significantly reduced. To solve this problem, it is necessary to reduce the tire pressure on the ground, which can be achieved by reducing the grip weight or developing and introducing new innovative tire designs. But, even new innovative tire designs have corresponding limitations due to the radial load interval, internal pressure, travel speed and the amount of torque on the wheel. These restrictions form the area of possible operating modes of tractor tires, individual sections of which differ significantly in terms of traction efficiency and environmental friendliness. Within the limits of possible modes of operation of the tire, operating modes must be implemented in areas of high efficiency and environmental friendliness. The materials of this article are basic in the study and substantiation of rational operating modes of tractor agricultural tires, and also provide prerequisites for the formation of recommendations for improving the traction efficiency and environmental friendliness of wheeled tractors
13
Truflyak, E. V. "Intelligent technology for determining the optimal air pressure in the tires of agricultural tractor wheels". Agricultural Engineering, n. 2 (2024): 13–19. http://dx.doi.org/10.26897/2687-1149-2024-2-13-19.
Testo completoAbstract (sommario):
The use of powerful tractors and wide-beam agricultural machinery, which have a strong compaction effect on the soil, is conditioned by the agricultural production profitability. The lack of a holistic systematic approach to reducing the anthropogenic compaction effect of wheel propulsors and working units of modern energy-intensive heavy machinery on the soil of agricultural landscapes requires the improvement of methods for determining the optimal air pressure in the tires of agricultural tractors. For this purpose, the authors developed an intelligent technology for determining the optimum air pressure in the various types of tires used in agricultural tractors. The problem was solved by processing “large” arrays of data on operating machine and tractor units and agrolandscapes in order to increase crop yields. Collection and analysis of primary data required for training the neural network were conducted on the fields of the Republic of Adygea during the cultivation of winter barley and winter wheat with the use of machinery equipped with Michelin AXIOBIB2 low-pressure tires. The Feed forward neural network was applied. Fourteen parameters were used as input factors to the neural network: types of soil, machinery and tires; field coordinates; presence and type of mounted equipment; season; type of tillage; granulometric composition, moisture and soil density; wheel diameters; motion speed of machines; field slope; agricultural background. The task set presumed the yield parameter as the main target function. The neural network pre-trained on a significant amount of input data calculates the optimal air pressure in tires when inputting the necessary data. Based on the designed software, the authors plan to develop a system of automatic adjustment of tire inflation depending on the incoming factors made in the offline and online modes.
14
Gorodetskiy, K. I., A. P. Parfenov e A. M. Lavlinskiy. "GENERALIZED TRACTION INDICATORS OF AGRICULTURAL TRACTORS". Traktory i sel hozmashiny 84, n. 2 (15 febbraio 2017): 3–8. http://dx.doi.org/10.17816/0321-4443-66246.
Testo completoAbstract (sommario):
In 1972 G.G. Kolobov and A.P. Parfenov published the monograph «Traction characteristics of tractors». The monograph generalized numerous results of field tests of domestic wheeled and caterpillar tractors of that time, conducted by machine testing stations in various soil and climatic zones of the USSR. This had an impact on formulation and study of the issue of determining of tractors slippage, and in general, the study of their traction characteristics. Averaging of the experimental data was carried out according to the formulas and coefficients developed by the authors of the monograph. The obtained dependencies, hereinafter referred to as traction characteristics of tractors, establish the dependence of the coefficient of usable traction (specific traction force on the hook) on the slipping of tractors of various types on different soils. By now, the concept of the role of the studies in research of the interaction of a wheel and track with the surface has changed. The standards have been introduced to limit slipping of agricultural tractors, considering the negative impact of their propulsors on the soil. There is a need to clarify the terminology used earlier in order to unify the same meaning terms used in different, but related technical disciplines. Objectives of work are: rethinking of previous research results and assessing their relevance; distinction between the physical meaning and concepts of the traction coefficient and the coefficient of usable traction (specific traction force on the hook); determination of traction capabilities of wheeled and caterpillar tractors on natural agrotechnical and asphalt-concrete surfaces, considering current slippage limitations. It was proposed for the purposes of engineering calculations in assessing traction performance of tractors to use as a traction coefficient of various propulsors its value corresponding to the maximum slipping on the appropriate agro-technical background or dry concrete. It is also found that the limitations on slipping of tractors on metal caterpillars are overstated on all soil backgrounds, since they rather characterize the «stop» mode of the tractor, than the beginning of the unstable operation of the engine. The parameters of traction characteristics of 4x4 wheeled tractors require correction based on statistical replenishment with the initial data on traction tests of such tractors having a layout that considers the increased role of the front drive axle in creating the tractor pulling power. For 4x2 tractors traction characteristics are at the same time characteristics of traction performance of individual driving wheels (tires). Therefore, having such data on all available driving tires of different dimensions, it is possible, at the development stage, to determine traction properties of newly created different variants of machines, including all-wheel drive.
15
Revenko, V. Yu, A. N. Nazarov e V. I. Skorlyakov. "Method of calculating the pressure on the soil of wheeled tractors". Agricultural Science Euro-North-East 24, n. 5 (31 ottobre 2023): 868–76. http://dx.doi.org/10.30766/2072-9081.2023.24.5.868-876.
Testo completoAbstract (sommario):
The market of tractors in Russia has changed greatly in recent years. A number of new suppliers have appeared on the market, abandoned brands are replaced for Russian analogues and machines from friendly countries. It is hard to evaluate all the quantitative and qualitative diversity of tractors provided to agricultural producers through the system of machine tests, especially considering that every manufacturer has a large number of standard size ranges of power equipment. Nevertheless, the customer should have access to information about the basic consumer properties and the degree of effectiveness of a particular machine unit. The article provides a computational method for evaluating one of the most important functional indicators of tractors, namely, the level of impact of its wheels on the soil, using limited initial information: technical characteristics and operational documentation of the manufacturer. The algorithm given in the text was approved during testing real tractor samples. Insignificant differences in the assessment of the maximum pressure on the soil, obtained as a result of measurements and calculations (the difference is 1.9-3.3 %) indicate a high degree of reliability of the developed methodology, as well as the possibility of its application in engineering practice to evaluate the functional indicators of tractors, including taking into account changes in their size and mass parameters when equipped with ballast weights, agricultural machines, implements, dual tires, etc. To make calculations, it is enough to know the weight of the tractor, the weight of ballast loads (mounted implements), the size of the installed tires, their static radius and the amount of tire inflation pressure. The methodology will significantly improve the quality of the predictive assessment of the level of impact on the soil of both mass-produced and designed tractor equipment.
16
Szente, Márk. "Slip Calculation and Analysis for Four-wheel Drive Tractors". Progress in Agricultural Engineering Sciences 1, n. 1 (1 novembre 2005): 7–31. http://dx.doi.org/10.1556/progress.1.2005.1.2.
Testo completoAbstract (sommario):
The objective of the research of tires was to determine the dynamic rolling radius and to apply it to wheel slip calculations with special respect to vertical wheel load and to tire inflation pressure. It is typical of mechanical four-wheel drive tractors that there is a definite additional power in the tractor power chain. This additional power is dependent on the difference between the front wheel and rear wheel peripheral speeds. Further-more, the purpose was to determine the effect of additional slip on four-wheel drive tractors operated without drawbar pull. Experiments were performed on asphalt surfaces and fields. A new measurement method was developed, and a device was constructed for the implementation of three tractor wheel drive operational modes (four-wheel drive, rear-wheel drive and front-wheel drive). As the result of the experiments, a relationship was found to describe the dynamic rolling radius for low-profile radial tires tested on rigid road surfaces. On this basis, the classical slip calculation method was modified. This phenomenon appears only on hard roads and soil surfaces with high adhesion coefficients and only within the low drawbar pull range.
17
Okunev, G. A., V. L. Astaf'ev e N. A. Kuznetsov. "Reduction of aftereffect of machine units on the soil". Traktory i sel hozmashiny 83, n. 12 (15 dicembre 2016): 43–47. http://dx.doi.org/10.17816/0321-4443-66293.
Testo completoAbstract (sommario):
Cultivation of crops is associated with multiple passes of machine units through the fields. The cumulative effect of soil compaction caused by repeated impacts of movers of machine units is considered as especially dangerous. The most intensive compaction process occurres in spring. The repeated passes of heavy machines and the compaction of surface and subsurface soil horizons lead to the decrease in yield potential of fields. The solving of compaction problem depends on the soil and climatic conditions, zonal cultivation technologies and crop harvesting, and on the machine system in operation. When forming the machine and tractor fleet of enterprises, the selection of general-purpose tractors serves as a basis. The least negative impact on the soil occurs when crawler tractors are used. The advantage of wheeled tractors is the possibility of their use for both field works and transport operations. But today the wheeled tractors are hardly used for transport operations because of their increased weight and power, which shows the necessity of use of such heavy crawler tractors as Ruslan and Challenger. Their use in combination with wheeled tractors of middle class allows to improve significantly the structure of machine and tractor fleet. The main power unit for farm enterprises with 1000 hectares of arable land is a general-purpose tractor of the 3rd traction class. The use of the HTZ-150K-09 tractor with 23.1R26 low-pressure tires with the air pressure of 80 kPa provides a permissible impact on the soil. The soil density in the surface layer reduces to 0.06 grams per cubic centimetre as compared to the use of 21.3R24 single wheels. This allows to put such tractor in operation for spring field works.
18
Okunev, G. A., e N. A. Kuznetsov. "Aspects of the development of the type of tractors and trends in the technical re-equipment of production units of various types". Izvestiya MGTU MAMI 11, n. 1 (15 marzo 2017): 16–22. http://dx.doi.org/10.17816/2074-0530-66888.
Testo completoAbstract (sommario):
Domestic and neighboring countries industry produce wheel and tracked tractors, which differ from each other by various parameters. The variety of general-purpose tractors offered on the market puts producers in the forefront of the choice of acquiring equipment to perform a set of technological operations. A comparative evaluation of the use of wheeled and caterpillar tractors of various traction classes on basic technological operations showed an increase in operating costs per unit of work performed with increasing parameters of tractors, especially wheeled propellers. The use of wheel tractors of high traction classes is accompanied by an increased specific pressure on the soil even on twin tires due to the increase in track width. Use of wheeled tractors with a power of over 350 hp on transport works is not advisable. This reduces the annual load and further increases the cost of performing technological operations. As a result, the competitiveness of a caterpillar tractor of high traction classes is substantially increasing. The wheel tractor is suitable only for maneuvering over long distances. As a result of the reform of agricultural production, a multi-fold system of economic activities of enterprises has developed. Along with large holdings and production units on the basis of former collective and state farms, a considerable proportion is made up of farm households. As a general-purpose tractor for farming a wheel-driven machine with engine power of 150-200 hp is used. A tractor of the MTZ-80 type is needed to perform auxiliary works to ensure the operation of the main unit. The tractors park of the large grain enterprises consists of high-performance wheeled vehicles of class 6-8, as well as class 3-4 tractors on wheels for auxiliary work. The bulk of the land in processing in the region is accounted by enterprises formed on the basis of former state farms and collective farms. These are diversified economies of grain and livestock farming. Multisectoral production allows to form a more developed structure of sown areas due to the cultivation of different cultures. To perform a set of works in these farms caterpillar tractors of class 4-5 and wheeled tractors of general purpose of class 3-4 are needed.
19
Lavrov, A. V., V. G. Shevtsov, A. V. Rusanov e V. A. Kazakova. "Matching the Traction Qualities of Agricultural Mobile Power Vehicles with the Permissible Maximum Pressure on the Soil". Agricultural Machinery and Technologies 14, n. 3 (25 settembre 2020): 9–14. http://dx.doi.org/10.22314/2073-7599-2020-14-3-9-14.
Testo completoAbstract (sommario):
Modern highly mechanized agricultural production is characterized by the incompatibility of simultaneous matching of the maximum pressure of agricultural mobile equipment movers on the soil and the possibility of increasing the tractors energy saturation when equipping them with existing wheel engines.(Research purpose) To coordinate the maximum pressure on the soil with the permissible norms, weight utilization factors and the level of tractors energy saturation.(Materials and methods) The authors used a calculated method for determining the maximum pressure on the soil using a universal tire characteristic.(Results and discussion) The authors found that when performing spring works on closing moisture and sowing row crops at a maximum pressure of 80 kilopascals, corresponding to all types of soil, the most mass universal row tractor Belarus 1020 had a maximum pressure of 150 kilopascals, which was 70 kilopascals higher than the permissible one for the corresponding crop shortage. They found that replacing ordinary tires with agrophilic tires could increase the area of the contact spot by 16 percent, while reducing the coefficient of unevenness and increasing the coefficient of use of the adhesion weight. The main condition for replacing ordinary tires with agrophilic tires was to keep the traction force unchanged.(Conclusions) Summarizing the results of the research as agrophilic direction, ensuring the compliance impacts on soil and positively solving the problems of saturation, it is possible to recommend the development of navigation systems in achieving utilization hitch weight equal to 0.5 (low tire pressure), equal to 0.6 (rubber joint with torsion bar suspension) and 0.7 (rubber track). It was found that the conducted research, taking into account the available data on traction tests of the T-250 tractor, would allow to include an agrophilic concept with a hypothetical dependence of the adhesion weight use factor on the longitudinal unevenness coefficient in the revised State Standard 27021-86 “Agricultural and forestry Tractors. Traction classes”.
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Kotsar, Yu A., A. A. Nitkin e O. S. Kochegarova. "Features of operation of tractors on double tires". Agrarian Scientific Journal, n. 9 (24 settembre 2018): 61–64. http://dx.doi.org/10.28983/asj.v0i9.442.
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Anisimov, Nikolay L., Eduard I. Efimov, Roman Yu Dobretsov e Mikhail I. Dmitriev. "Selection of the analytical dependency for assessment of slipping of the Kirovets K-7 wheeled agricultural tractor". Izvestiya MGTU MAMI 17, n. 1 (24 giugno 2023): 25–33. http://dx.doi.org/10.17816/2074-0530-120130.
Testo completoAbstract (sommario):
BACKGROUND: The accuracy of prediction of towing properties is related to selection of the analytical dependency for assessment of slipping in the process of development or modernization of agricultural tractor in order to define the correct configuration of a machine-tractor unit. The relevance of the study lies in justification of the dependency describing slipping of wheels of modern high-powered 4K4b tractors and needed for study of tractors towing properties.
AIMS: Justification of the analytical formula of slipping for better accuracy of towing properties prediction at development stages and modernization of 4K4b tractors and units conjugated to them.
METHODS: Known analytical dependencies of slipping were analyzed in the study in order to compare the theoretical assessment results with the results of field-testing at harvest field carried out at machine testing stations according to common method. The theoretical and experimental results were obtained for the Kirovets K-7 series agricultural wheeled tractors. The experimental data of the Kirovets K-7 series tractors was approximated in order to find new dependencies for analytical determination of slipping at harvest field. The approximation coefficient was taken as the criterion for assessment of accuracy of experimental data description by the dependencies.
RESULTS: Among the considered analytical dependencies for prediction of slipping coefficient value, the equations which describe the experimental data of towing testing of the Kirovets K-7 series tractors the most satisfactorily were outlined. Based on approximated experimental data, the equations of slipping depending on specific towing force were obtained. There is the equation common for all tested tractors and there are separate equations for tractors with 32-inch and 38-inch tires. These equations provide with the best approximation of description of tractors. Values of specific towing force correlating to maximal towing efficiency and acceptable slipping coefficient of 16% for the Kirovets K-7 series tractors were obtained.
CONCLUSIONS: Some existing and new proposed in the article equations can be used for prediction of values of slipping coefficient at creating of potential towing characteristic for high-powered 4K4b tractors.
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Lindhorst, Caleb M., Roger M. Hoy, Santosh K. Pitla e Michael F. Kocher. "Dynamic ROPS Test for Tractors over 6,000 Kilograms". Transactions of the ASABE 61, n. 1 (2018): 53–62. http://dx.doi.org/10.13031/trans.12499.
Testo completoAbstract (sommario):
Abstract. OECD static tests (Codes 4, 6, 7, and 8) for agricultural rollover protective structures (ROPS) have become accepted standards for evaluating the ability of these structures to protect the operator during tractor rollover events. The strength properties of some materials typically used in ROPS change because of cold weather embrittlement at low temperatures. The static ROPS tests lack the ability to evaluate the strength of these structures during cold weather. The use of the dynamic ROPS test is well noted as a means for proving cold weather embrittlement resistance properties. Unfortunately, application of the OECD dynamic ROPS test (Code 3) is restricted to tractors with unballasted mass greater than 600 kg and generally less than 6,000 kg. The analyses presented in this technical note were undertaken to evaluate the extension of the OECD Code 3 dynamic ROPS test to tractors with unballasted mass of 6,000 kg or more. Tractor unballasted mass and wheelbase data from 47 wheeled tractors tested at the Nebraska Tractor Test Lab from 2014 to 2016 were used to explore the possibility of using a dynamic test method for evaluating the ability of ROPS on tractors with unballasted mass greater than 6,000 kg to meet the safety requirements of agricultural tractor ROPS. The data were graphed and analyzed to determine the required pendulum drop height and energy values to be applied to the ROPS by extending the existing equations to tractors over 6,000 kg. For tractors over 6,000 kg mass, it was determined that pendulum drop heights were too great for practical use. Three pendulum masses were proposed for the dynamic ROPS test: a 2,000 kg pendulum for tractors with mass less than 7,000 kg, a 4,000 kg pendulum for tractors with mass of 7,000 kg or more and less than 14,000 kg, and a 6,000 kg pendulum for tractors with mass of 14,000 kg or more and less than 23,000 kg. Alternate equations were developed for the drop height of each pendulum to meet the energy requirements that are expected to provide similar permanent deflections as those obtained when using the static ROPS test when considering the effect of strain rates on material properties. Tests should be conducted to determine how the results (permanent deflections) from the proposed dynamic ROPS test compare with results from the accepted static ROPS tests. It is further proposed that dynamic testing be conducted with the tractor rigidly restrained in a manner similar to the static test to better account for the wide variety of available tires and mountings for each tractor model. Keywords: Energy, Impact test, Pendulum, Reference mass, ROPS, Tractors.
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Zakharchenko, A. N., V. I. Balabanov, P. I. Gadzhiyev e G. G. Ramazanova. "Soil compaction by running systems of class 2 tractors". Traktory i sel hozmashiny 80, n. 6 (15 giugno 2013): 33. http://dx.doi.org/10.17816/0321-4443-65864.
Testo completoAbstract (sommario):
Procedure and results of field tests of narrow-tires tractors МТЗ-1221 and John Deere 6920 are given. The obtained data on soil density allows to develop recommendations on tractors use in tilled crops cultivation.
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Fanigliulo, Roberto, Marcello Biocca, Renato Grilli, Laura Fornaciari, Pietro Gallo, Stefano Benigni, Paolo Mattei e Daniele Pochi. "Assessment of the Performance of Agricultural Tires Using a Mobile Test Bench". Agriculture 13, n. 1 (28 dicembre 2022): 87. http://dx.doi.org/10.3390/agriculture13010087.
Testo completoAbstract (sommario):
The performance of agricultural tires varies with the characteristics of both the terrain and the tractors on which they are mounted, which differently affect the rolling resistance, the traction capacity, and the slip. To reduce the variability of test conditions, CREA developed an original mobile test (MTB) bench which consists of a dynamometric single axle trailer pulled by a tractor and can be used both in traction performance tests (driving wheels) and in rolling resistance tests (driven wheels). A control system alternatively operates the adjustment of traction force or slip, so that each test is performed maintaining constant the desired values. The MTB underwent tests under different conditions (type of surface, pre-set values of force of traction and slip) aimed at verifying its accuracy and reliability. In a final test, two pairs of identical new tires were simultaneously mounted on the MTB and on the rear axle of the 2WD tractor that pulled it, to discover information on the different interactions occurring, under the same traction conditions, between the soil surface and each pair of tires, with reference to the relationship between the slips and the load transfers observed on the MTB and on the tractor rear axle. The results evidenced the capability of the MTB to guarantee repeatable test conditions, including field conditions, allowing comparison among the performance of different tires.
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Nitkin, Alexey Anatolyevich, Yuri Alekseevich Kotsar e Olga Sergeevna Kochegarova. "Increasing efficiency of operation of agricultural tractors with double tires". Agrarian Scientific Journal, n. 3 (29 marzo 2021): 78–81. http://dx.doi.org/10.28983/asj.y2021i3pp78-81.
Testo completoAbstract (sommario):
The article discusses the problem of reducing the effectiveness of agricultural processes and performance indicators of a wheeled tractor with dual tires, which arises as a result of differences in the static radii of the outer and inner wheels of the tractor. Experimental tests of a wheeled tractor on dual tires using a measuring system based on a free-programmed controller “PLK-150c” are considered. Based on the results of the graphical analysis, recommendations are given to improve the performance of the operation of a wheeled tractor.
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Kalinin, Evgeniy, Olexander Saychuk e Nadiia Kolpachenko. "EQUATION OF MOTION OF THE JOHN DEERE 6095B TRACTOR AS AN AUTOMATIC DRIVING OBJECT". Vibrations in engineering and technology, n. 3(98) (30 ottobre 2020): 44–55. http://dx.doi.org/10.37128/2306-8744-2020-3-5.
Testo completoAbstract (sommario):
The main issue that has to be solved in the formation of modern systems for automatic driving of tractors is the issue of obtaining information about the current state of the machine-tractor unit relative to a given trajectory. In terms of its quality, this information should reflect the rather stringent requirements of agricultural production for the accuracy of trajectory control. Thus, to create devices for automatic driving of tractors, it is necessary to know the characteristics and properties of these machines as objects from the point of view of the theory of automatic control. When examining such machines, first of all, it is necessary to establish which parameter should be considered as input. With manual control, the feedback is closed visually on the right front wheel, more precisely at the point of contact of the wheel with the ground. The main goal of this work is to obtain equations connecting the input and output coordinates, as well as the input coordinate and coordinates of the middle of the front and rear axles of the tractor. It is also necessary to establish under what initial data a simplified equation can be used, taking into account only the kinematics of the tractor movement and not taking into account the elasticity of tires and deformation of the soil. For this, the problem is solved both taking into account the elasticity of tires and deformation of the soil, and without taking into account these factors. Frequency characteristics are compared, obtained using a simplified equation and taking into account the above factors at different speeds. During the research, the equations of motion of the tractor were obtained taking into account the deformation of pneumatic tires and soil. This equation allows you to study the movement of the tractor in the presence of external lateral forces. Such forces can be centrifugal forces when moving along a curved trajectory and forces from trailed and mounted implements on a tractor. The equation is valid for small steering angles of the tractor idler wheels. A simplified equation is obtained that does not take into account the deformation of tires and soil. This equation can roughly describe the movement of a tractor on solid ground, which is little deformed, at relatively low speeds. It is advisable to use this equation only at speeds not exceeding 1.7 m/s on dense ground. Both equations characterize the tractor as an object of regulation and allow the selection and design of an automatic steering system.
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Phromjan, Juthanee, e Chakrit Suvanjumrat. "Vibration effect of two different tires on baggage towing tractors". Journal of Mechanical Science and Technology 32, n. 4 (aprile 2018): 1539–48. http://dx.doi.org/10.1007/s12206-018-0307-5.
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Petrović, Predrag, Živko Stjelja, Predrag Popović e Branko Spajić. "Longitudinal and transverse operational stability of the tractor from the aspect of safety in agrotechnical operations". Poljoprivredna tehnika 48, n. 4 (2023): 87–99. http://dx.doi.org/10.5937/poljteh2304087p.
Testo completoAbstract (sommario):
Abstract: In the Republic of Serbia, despite a certain decrease in the number of accidents with tractors in the period 2010-2020., the number of injured and killed people is still high. In previous analyzes of the causes of accidents with tractors, the reports were formally reduced to the following: the operator was under the influence of alcohol; unsafe and unsuitable driving on terrains with ups and downs as well as rural and forest roads; malfunctions of controls for: braking, steering, transmission (switching on and off to save fuel), malfunction of tires, etc.; malfunctions and lack of light signaling; failure to establish the necessary ballast in relation to the required stability of the tractor, especially when moving uphill and down slopes; exploitation of a tractor without a cab or a safety frame; weak distraction, non-observance of traffic regulations, tractor driving by minors etc. In this paper, stability was considered when the tractor was moving up a slope, as well as when moving on a side slope through the balance of forces and factors that affect stability, i.e. the angle of inclination at which the tractor could potentially overturn. Those data obtained by analyzing the forces acting on the tractor are very important from the aspect of safety during exploitation in agrotechnical and transport-specific conditions.
29
Тretyak, V. M., V. V. Sheban, R. V. Oliadnichuk, O. F. Govorov e R. V. Melnik. "Influence of hinged device parameters on negative resonance oscillations during the operation of machine-tractor unit in transport mode". Mehanization and electrification of agricultural, n. 12 (2020): 129–36. http://dx.doi.org/10.37204/0131-2189-2020-12-15.
Testo completoAbstract (sommario):
Annotation Purpose. Reducing the influence of resonance phenomena on the structural elements of a tractor of the KIY 14102 type when driving with an attached implement in transport mode. Methods. To solve this problem means of graph-analytical constructions, analytical geometry, oscillation theory and theoretical mechanics were used. Results. On the basis of the graphic-analytical analysis of the kinematic diagram of the tractor attachment of the KIY 14102 type, it was found that the position of the instantaneous center of its rotation significantly depends on the change in the angle between the tractor frame and the levers, which are united by the CA-1 automatic connection device. The frequency range of forced oscillations of the tractor frame, which occur when driving in a certain speed range, can coincide with the relative natural frequency of the tractors, which leads to resonance phenomena. Resonant longitudinal-angular vibrations of the tractor frame reduce the normal reactions of the steered wheels with the supporting surface, which worsens controllability. Changing the frequency of the natural resonance of the elements connecting the tractor with the implement can be done by changing the kinematic stiffness of the mounted system. Conclusions 1. The kinematic diagram of the hinged device of tractors significantly affects the dependence of the position of the instantaneous center of rotation of the hinged device relative to the mass of the implement that is aggregated. 2. The existing parameters of the mounted systems of tractors of the KIY 14102 type can lead to the occurrence of resonance phenomena when driving in transport mode on unpaved field roads, which negatively affects the controllability of the MTA. 3. Reducing the resonant frequency of natural vibrations of the attachment system with the tool, by reducing the kinematic stiffness, improves the dynamics of the interaction of the elements of the machine-tractor unit with each other and with the supporting surface. Keywords: machine-tractor unit, clutch system, tests, dynamic loads, strain gauge measurements, air pressure in tires.
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Tarasov, V. N., I. V. Boyarkina, V. R. Edigarov e V. V. Malyy. "Analytical justification of the load capacity of pneumatic tires for tractors and agricultural machinery". Traktory i sel hozmashiny 84, n. 8 (15 agosto 2017): 21–27. http://dx.doi.org/10.17816/0321-4443-66324.
Testo completoAbstract (sommario):
Information on the parameters and operating modes of pneumatic tires for tractors and agricultural machinery is contained in state standards in the form of tables in digital form. The variety of types, sizes and designs of tires makes it difficult to determine the tire parameters taking into account conditions and operating modes. The information on the tire parameters is insufficient due to the lack of information about the contact area of the tire with a solid support surface. The article suggests the dependences of the load-carrying capacity of a tire on the generalized geometric parameter equal to the product of the outer diameter and width of the tire profile. The area of contact is an important parameter that affects the traction characteristics of the tractor, the depth of the track when driving on a plowed field and the resistance to movement of the tractor. New terms have been introduced - the theoretical and actual contact areas of the pneumatic tire. The dependence of the theoretical contact area on the generalized parameter equal to the product of the outer diameter and width of the tire profile for diagonal and radial tires is obtained. The cross-section method is used, by means of which the bus contact is cut off from the shell. In this case, the internal forces of the pneumatic tire framework are transformed into real external forces. The analytical dependence of the load capacity of a pneumatic tire is obtained, representing the algebraic sum of the lifting force of the shell and the vertical force of the frame. The universal formula is proposed for determining the actual contour area of the tire contact, in which the contact length and width are used. The values of the length and width of the contact, as well as the ratio of these quantities, are determined experimentally for different loads and pressures, the contact length being determined by the proposed analytical method.
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Mikheev, A. V., Z. A. Kostrova, V. V. Belyakov, D. V. Zezyulin e V. S. Makarov. "Analysis of possibilities for application of airless tires for motor-and-tractor vehicles and agricultural machinery". Traktory i sel hozmashiny 83, n. 5 (15 maggio 2016): 21–26. http://dx.doi.org/10.17816/0321-4443-66187.
Testo completoAbstract (sommario):
Ensuring of mobility and efficiency plays the key role in solution of problem of providing the stable, safe and efficient operation of mobile terrestrial motor-and-tractor vehicles, agricultural machinery, transport and technological complexes. At the present stage of development, for achievement of desired values of traction force and mobility, the application of airless tires becomes rational. This type of tires excludes the loss of mobility because of the loss of excessive internal gas pressure, and it is able to provide higher traction force in comparison with conventional pneumatic tires. As a result of analysis, it is found that the airless tires have characteristics similar to pneumatic ones, and they are fully capable to replace them. However, the airless tires cannot change stiffness properties during operation, in contrast to the pneumatic ones, in which the variation of value of excessive gas pressure inside the tire leads to stiffness change. Therefore, it is necessary to introduce in the design of airless tire an elastic element with characteristics that can vary during operation. Such elastic element could be represented by pneumatic muscles, electroactive polymer or special mechanical design of crosspieces-spokes. Introduction of elastic element with variable characteristics in the design of airless tire leads to the increasing of mobility and efficiency of tractors and agricultural machinery. It will make possible the automatic control of tires' parameters by means of electronic control units, without operator's assistance, thereby the human factor will be reduced to a minimum.
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Bulgakov, Volodymyr, Aivars Aboltins, Semjons Ivanovs, Hristo Beloev, Volodymyr Nadykto, Yevhen Ihnatiev e Jüri Olt. "Theory of Movement of Machine-Tractor Unit with Trailer Haulm Harvester Machine". Applied Sciences 12, n. 8 (12 aprile 2022): 3901. http://dx.doi.org/10.3390/app12083901.
Testo completoAbstract (sommario):
Harvesting sugar and fodder beet tops is a complex technological process that requires the use of special harvesting machines. Trailed harvesters of different rows, which together with aggregate tractors form symmetric or asymmetric machine-tractor units, the movement of which in the horizontal plane is not always stable, are widely used. The purpose of this study is to determine the parameters of stable plane-parallel motion of asymmetric harvester machine-tractor unit based on numerical computer simulation of the obtained analytical dependencies. According to the results of the analytical study, the values of the amplitude and phase-frequency characteristics of the turning angle tractor’s oscillations were obtained. They reflect the reproduction by the angle rotation fluctuations of the haulm harvester machine in the horizontal plane. Calculations have shown that reducing the value of the input resistance coefficient of pneumatic tires of the driving wheels of the aggregating tractor increases its sensitivity to the action of disturbing influences. The greater the sensitivity, the closer the wheels of the power tool are to the attachment point of the trailed haulm harvester. In qualitative terms, increasing the speed of the machine-tractor unit from 1.5 to 2.5 m∙s−1 leads to an undesirable increase in the amplitude-frequency response and desired increase in the phase-frequency response when reproducing its external disturbing effects in the form of oscillations of the angle of rotation of the harvester.
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Podrubalov, Maxim, e Mikhail Mekhedov. "DESIGN FEATURES OF TRACTORS FOR WORK ON SLOPES". SCIENCE IN THE CENTRAL RUSSIA, n. 2 (28 aprile 2023): 148–53. http://dx.doi.org/10.35887/2305-2538-2023-2-148-153.
Testo completoAbstract (sommario):
The problems of creating tractors, self-propelled chassis, forestry and agricultural machines of special designs for the mechanization of crop production, land reclamation and construction in hard-to-reach conditions of forest, agricultural and mountain lands are considered in the work. A comparative analysis of design solutions that have found application in domestic and foreign tractors used in the performance of technological and transport operations on sloping lands and badlands in agriculture and forestry is given. It is noted that a number of models of universal row-crop tractors provide for the possibility of increasing stability by turning the housings of the remote final drives relative to the rear axle housing. For tractors, at the same time, the wheelbase increases and the ground clearance (ground clearance) decreases. It is indicated that the analysis of the features of the operation of wheeled tractors on the slopes made it possible to substantiate the methods and means that improve their main indicators: differential lock; lowering the center of gravity; the use of tires with high lugs, additional steel wheels, lugs, expanders; the use of half-tracks and wheeled tractors with a 4K4 wheel arrangement. The advantages and disadvantages of using tracked and wheeled tractors as the base machine have been established. Slope preference for tractors with front drive axle. Such tractors, equipped with the previously listed devices, have better traction properties, maneuverability and controllability, approaching caterpillar tractors in these indicators. Recommendations for the implementation on slopes, forest and agricultural lands of all-wheel drive low-clearance wheeled tractors are given in the work. In conclusion, it is indicated that, despite the considered features, when creating tractors for working on small-contour plots located on slopes up to 25 °, preference is given to wheeled low-clearance tractors, which is caused by a cheap design due to minor design changes compared to the basic models.
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Melikov, Izzet, Vladimir Kravchenko, Sergey Senkevich, Elnara Hasanova e Lyudmila Kravchenko. "Traction and energy efficiency tests of oligomeric tires for category 3 tractors". IOP Conference Series: Earth and Environmental Science 403 (19 dicembre 2019): 012126. http://dx.doi.org/10.1088/1755-1315/403/1/012126.
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Revenko, V. Yu. "New Methods for Determining the Area of the Contact Surface of Tires of Agricultural Machines and Tractors". Machinery and Equipment for Rural Area, n. 2 (26 febbraio 2023): 10–15. http://dx.doi.org/10.33267/2072-9642-2023-2-10-15.
Testo completoAbstract (sommario):
The advantages and disadvantages of existing methods for estimating the size of the tire contact patch are considered, new methods for determining the area of the contact surface of tires of agricultural machines and tractors (the "pixel count" method and the method for converting a raster image of a print into a vector format) are presented.
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Abrahám, Rudolf, Radoslav Majdan, Katarína Kollárová, Zdenko Tkáč, Eva Matejková, Soňa Masarovičová e Róbert Drlička. "Spike Device with Worm Gear Unit for Driving Wheels to Improve the Traction Performance of Compact Tractors on Grass Plots". Agriculture 14, n. 4 (29 marzo 2024): 545. http://dx.doi.org/10.3390/agriculture14040545.
Testo completoAbstract (sommario):
In general, energy loss reduction via the interaction of tires with the ground improves tractor traction performance when a drawbar pull is generated. This paper is examines the driving wheels with steel spikes for a tractor equipped with modern radial tires. An improved design of the spike device that allows for the change between an active and inactive position of the spikes is presented. The traction performance of a compact articulated tractor with the spike device was tested on a grass plot with two soil moisture contents (SMC). The highest difference in the drawbar pull in the range from 14.2% to 40.5% and from 17.1% to 36.8% was reached by the spikes in the active position in comparison with the tires without spikes, which were at the slip range from 45% to 5% in the case of the low SMC when the test tractor was in the 3rd and 1st gear. The motion resistance difference between the spikes in the active position and the tires without spikes was 11.8% and 2.5% at the low and medium SMC, respectively. At the low and medium SMC, the highest tractive efficiency of 0.765 (0.721) and 0.757 (0.731) was reached by the spikes in the active position when the test tractor was in the 1st (3rd) gear in comparison with 0.736 (0.7) and 0.723 (0.708) in the case of the tires without spikes. The results indicated that the spike device allowed for the improvement of tractor tractive performance.
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Song, Hyun Seok, Kyung Seok Sim e Tae Won Park. "Optimal tread design for agricultural lug tires determined through failure analysis". Journal of Agricultural Engineering 49, n. 1 (5 aprile 2018): 64–70. http://dx.doi.org/10.4081/jae.2018.685.
Testo completoAbstract (sommario):
Agricultural lug tires, commonly used in tractors, must provide safe and stable support for the body of the vehicle and bear any additional load while effectively traversing rough, poor-quality ground surfaces. Many agricultural lug tires fail unexpectedly. In this study, we optimised and validated a tread design for agricultural lug tires intended to increase their durability using failure analysis. Specifically, we identified tire failure modes using indoor driving tests and failure mode effects analysis. Next, we developed a threedimensional tire model using the Ogden material model and finite element method. Using sensitivity analysis and response surface methodology, we optimised the tread design. Finally, we evaluated the durability of the new design using a tire prototype and drum test equipment. Results indicated that the optimised tread design decreased the tire tread stress by 16% and increased its time until cracking by 38% compared to conventional agricultural lug tires.
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Grigorev, Igor, Ol’ga Kunickaya, Evgeniy Tikhonov, Edward Hertz, Anna Khakhina, Olga Burmistrova, Natalia Sukhomlinova e Artem Zhuk. "Methodology for Assessing and Managing the Environmental Performance of Skidding and Feller Buncher Tractors". Forests 12, n. 12 (7 dicembre 2021): 1723. http://dx.doi.org/10.3390/f12121723.
Testo completoAbstract (sommario):
Systematic assessments on the effects of skidding systems on features of forest blueberry pine soil were conducted as part of this study. Assessing the ecological efficiency of forest skidding machines showed that the most significant impact (by 2.0–2.2 times) on soil compaction was observed at loading sites rather than during transportation. Lightweight loam density and sand density increased by 25% and 2%, respectively, after more than two passages of the skidding system. Pressure in 33L-32 tires of forestry machinery in operation on a solid surface varied from 46.5 kPa to 196 kPa at maximum load. Studying the impact of tires on soil compaction showed that the environmental efficiency of forestry equipment can be enhanced if the optimal tire pressure at average loads does not exceed 70 kPa for tracked vehicles and 150 kPa for wheeled vehicles in summer seasons. When ground grips were fully immersed, the pressure of forwarders on soil was reduced. These study results can be used to establish organizational and technological measures in order to manage the negative impact of skidding systems and to increase the environmental effects of their performance.
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Nadykto, Volodymyr, Gennadii Golub, Volodymyr Kyurchev, Nataliya Tsyvenkova, Gennadii Petrov e Yaroslav Yarosh. "Determining vertical oscillations of front-plow tractor without support wheel". Eastern-European Journal of Enterprise Technologies 1, n. 7 (127) (28 febbraio 2024): 37–47. http://dx.doi.org/10.15587/1729-4061.2024.296842.
Testo completoAbstract (sommario):
The object of this study is a tractor with a front plow without a support wheel. One way to avoid the use of ballast is to use front-mounted plows that operate under the "push" mode. As a rule, such plows are equipped with at least one supporting wheel. The presence of the latter complicates the structure of the plow and, of course, affects the degree of vertical load on the steered wheels of the mobile vehicle. With the help of the constructed mathematical model and the corresponding amplitude and phase frequency characteristics, the dynamics of vertical oscillations of the front axle of a tractor with a front mounted plow without a support wheel were investigated. Vertical fluctuations of the total force acting on the tractor from the side of the plow were considered as a disturbing influence. According to the simulation results, an increase in the vertical load of the front axle of the tractor by 600 kg causes a desired decrease in the value of the amplitude and an increase in the phase of external disturbances of the dynamic system. The higher the frequency of disturbance oscillations, the more acceptable these characteristics become. It was established that in order to improve the response of the studied dynamic system to disturbances, it is necessary to reduce the stiffness coefficient of the tires of the front wheels. In practice, this is achieved by adjusting the air pressure in the tires. The amplitude-frequency characteristics of the system almost do not change when the damping coefficient of the tires of the front wheels of the tractor is increased in the range from 1 to 3 kN·s/m, while the phase-frequency characteristics improve. This is especially noticeable at the frequencies of oscillations of the disturbing influence in the range of 0–10 s-1. The results could be used as a basis for evaluating the efficiency of tractors with a front plow without a support wheel in tillage operations. Such efficiency can be achieved under the condition of practical implementation of the recommendations proposed in this paper regarding the selection of design parameters of tires for the front wheels of the tractor
40
Grigorev, Igor, Olga Kunickaya, Albert Burgonutdinov, Evgeniy Tikhonov, Valentin Makuev, Sergey Egipko, Edward Hertz e Maksim Zorin. "Modeling the effect of wheeled tractors and skidded timber bunches on forest soil compaction". Journal of Applied Engineering Science 19, n. 2 (2021): 439–47. http://dx.doi.org/10.5937/jaes0-28528.
Testo completoAbstract (sommario):
An increasing demand for forest products incites a large number of log transportation operations, which may lead to negative consequences for the soil and the ecosystem as a whole. This paper is focused on establishing a mathematical model to estimate the soil deformation and compaction processes under tires of wheeled forest machines and individual components of the skidding system such as forwarder, limbs, butts, and tops of tree-lengths in high latitudes, permafrost soil and forests. The method applied is based on simulating the impact processes of elastic tires and the skidding system on the soil through a mathematical device for the measurement of the compaction parameters for different types of soil and the size of the shelterbelt. The effectiveness of the proposed models was evaluated according to experimental results. The influence of the rheological (elastic, viscous, and plastic) properties of soil were studied. The elasticity of tires and the running speed of forest machines can help to control the performance of forest machines. This can be done by reducing the pressure exerted on the soil and increasing the number of skidder passes 1.5-2-fold. Comparative analysis showed that the calculated data differ from the experimental ones by no more than 10%. The obtained results and the developed model will allow for a qualitative and quantitative assessment of technological impact on the soil during the projecting maps for logging operations.
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Bulgakov, Volodymyr, Simone Pascuzzi, Volodymyr Nadykto, Valerii Adamchuk, Viktor Kaminskiy, Volodymyr Kyurchev e Francesco Santoro. "Effects of Tractor and Soil Parameters on the Depth of the Permanent Traffic Lanes in Controlled Traffic Farming Systems". Applied Sciences 12, n. 13 (30 giugno 2022): 6620. http://dx.doi.org/10.3390/app12136620.
Testo completoAbstract (sommario):
One of the basic requirements for controlled traffic farming (CTF) is the precise motion of all agricultural equipment on permanent traffic lanes (PTL). Tractors of machine-tractor units are then equipped with a GNSS (global navigation satellite) RTK (real-time kinematic) system, even though in many parts of the world, and Europe as well, satellite navigation is not yet used. In this case, for implementation of the CTF system, it needs to lay such PTL tracks that would be sufficiently visible, especially when using the CTF system in multi-year agricultural crop cultivation. The PTL track depth is influenced by both tractor and soil parameters and, in this paper, this influence is studied considering the dimensionless π-terms of the similarity theory. To obtain a greater depth of PTL tracks (h), the soil cone index must be low. The low density of the soil is important, even if its effect on the parameter h is less than that of the soil cone index. A greater depth of PTL tracks is also obtained by increasing the inflation pressure in the tractor tires. Ballasted wheels are the least effective for increasing the value of the parameter h.
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Kravchenko, Vladimir Alekseevich, Lyudmila Vladimirovna Kravchenko e Izzet Melukovich Melikov. "Evaluation of traction-chain properties of powerful tractors and combines complete with varieties of various performance". Agrarian Scientific Journal, n. 8 (31 agosto 2020): 83–88. http://dx.doi.org/10.28983/asj.y2020i8pp83-88.
Testo completoAbstract (sommario):
The purpose of this study is to determine the traction and coupling properties of the undercarriage systems of wheeled mobile energy vehicles equipped with tires with different internal structures of the tire cover. It has been proved that the breaker ply rating for class 5 tractor should be equal to four, the carcass ply rating should be equal to six, the cord threads of the breaker and the carcass should have the slope of 70 and 0? respectively; the values of the corresponding tire parameters should be: 7, 6, 62, 15? for the propulsor of a combine. It has been established that when the undercarriage systems are equipped with experimental tires, the traction and coupling properties of mobile energy vehicles are improved.
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An, Yuhui, Lin Wang, Xiaoting Deng, Hao Chen, Zhixiong Lu e Tao Wang. "Research on Differential Steering Dynamics Control of Four-Wheel Independent Drive Electric Tractor". Agriculture 13, n. 9 (4 settembre 2023): 1758. http://dx.doi.org/10.3390/agriculture13091758.
Testo completoAbstract (sommario):
Traditional tractors can only achieve steering through mechanical structures such as steering knuckles and steering trapezoids. Among them, the mechanical structure is more complex, and various parts are easily damaged, making the tractor malfunction. The four-wheel independent drive differential steering mode differs from the traditional Ackermann steering mode, which realizes steering by controlling the inner and outer wheel torque, which can accurately steer the working state of high-end agricultural machinery equipment and improve the operating efficiency of agricultural machinery equipment. Aiming at the dynamic control problem in the steering of electric tractor four-wheel independent drive, a layered control strategy based on the sliding mode control of yaw torque at the upper level and the optimal torque distribution level based on the mean load rate of vehicle tires at the lower was proposed. By analyzing the differential steering mechanism of a four-wheel independent drive, a dynamic model of differential steering of the electric tractor is established, and a dynamic controller of a four-wheel independent drive is designed according to the layered control strategy. The upper controller tracks and controls the expected yaw speed on the basis of the sliding mode control to track the driver’s intention, and the lower controller realizes the optimal torque distribution based on the principle of the optimal average load rate of the vehicle tire to ensure the steering stability of the electric tractor. The effect of the controller was simulated and analyzed under typical conditions of double line shift, serpentine, and step. The results showed that the sliding mode controller is better than the PID controller in driver intention tracking. Compared with the average allocation strategy, the average maximum load rate of the vehicle tire under the three working conditions is reduced by 16.9%, 13.8%, and 17.3%, respectively, which proves the effectiveness of the layered control strategy. In the real car test, the sliding mode controller is better than the PID controller in the driver intention tracking. This study has important guiding significance for improving the maneuverability and stability of electric tractors.
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ATLI, Hüseyin Fatih. "Safety of agricultural machinery and tractor maintenance planning with fuzzy logic and MCDM for agricultural productivity". International Journal of Agriculture, Environment and Food Sciences 8, n. 1 (7 febbraio 2024): 25–43. http://dx.doi.org/10.31015/jaefs.2024.1.4.
Testo completoAbstract (sommario):
Productivity is one of the most important measures used to determine the growth and development level of countries or sectors. A wide variety of projects have been planned and implemented to increase agricultural productivity. The productivity to be obtained in agriculture; Soil conditions, climate, seeds, fertilizer, pesticides, labor and agricultural mechanization directly affect it. Agricultural mechanization is the realization of agricultural activities by using energy together with agricultural tools and machines. Agricultural mechanization; It is an important agricultural production technology that helps increase agricultural productivity. Due to the inadequate maintenance planning of agricultural machinery, agricultural machinery cannot be utilized at the desired level in agricultural production. Most agricultural equipment is subject to frequent changes in speed and direction of movement while operating. Damage that can be seen on a single machine; It also causes other machines to malfunction. During the year, especially in the months when agricultural activity is high, excessive working tempo can cause tractors to malfunction. The breakdown of tractors causes disruptions in agricultural activities. In addition, the breakdown of tractors increases the repair costs. Since there is no tractor maintenance planning, farmers face interruptions in agricultural activities due to tractor malfunction. However, tractor malfunctions may cause cost and economic losses. For these reasons, there is a need for appropriate maintenance planning of agricultural machinery in order to continue agricultural activities without disruption. Maintenance planning; It consists of a set of preventive activities to improve the reliability and availability of any system. The main purpose of this study is to determine and rank the importance level weights of the criteria that are important for agricultural machinery maintenance planning using the fuzzy AHP method. Fuzzy AHP method, which provides ease of application, was preferred in determining the Criterion Weights. The research proposes a framework to determine the weights of appropriate criteria for care planning selection through a combined approach of fuzzy multi-criteria decision making involving relevant stakeholders. On the basis of the prioritization of criteria of tractor maintenance planning (TMP), it was found from the ranking that checking for all fluid levels (TMP1) ranked first. This respectively is followed by checking for general conditions (TMP4), checking for tires and wheels (TMP2) and checking for batteries (TMP3). With the results of the study, a guide was created for farmers and other stakeholders, as well as decision makers, to help plan the maintenance of machines in better working conditions. It is also thought that this study will be encouraging for other studies.
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Tarhan, Sefa, e Kazim Çarman. "Modeling the Torque and Power Requirements of Traction Tires of Horticultural Tractors using Dimensional Analysis". Mathematical and Computational Applications 9, n. 3 (1 dicembre 2004): 427–34. http://dx.doi.org/10.3390/mca9030427.
Testo completo
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Zazulya, A. N., O. B. Filippova e I. G. Golubev. "Method for Determining the Pressure of a Pneumatic Wheel on the Soil". Machinery and Equipment for Rural Area, n. 12 (22 dicembre 2021): 29–31. http://dx.doi.org/10.33267/2072-9642-2021-12-29-31.
Testo completoAbstract (sommario):
A method for determining the pressure of a pneumatic wheel on the soil is proposed. The method consists in measuring the magnitude of the vertical acceleration of the axles of a self-propelled vehicle, its speed and air pressure in the tire. The research results allow the developers of vehicles fitted with pneumatic wheels to choose rational characteristics of tires and optimal parameters of the oscillatory system of wheeled tractors, which help to reduce soil compaction.
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Revenko, V. Yu, S. S. Frolov, A. N. Tkachenko e A. B. Ivanov. "Refined method for determining the current agricultural machinery tire wearing surface area". Machinery and Equipment for Rural Area, n. 7 (26 luglio 2021): 10–15. http://dx.doi.org/10.33267/2072-9642-2021-7-10-15.
Testo completoAbstract (sommario):
It has been established that the predictive assessment of the level of impact on the soil of tractors and agricultural machines is based on the calculation of the specific pressure equal to the ratio of the vertical load to the propeller contact surface area. A mathematical model is proposed that has been developed based on the results of field tests of a large number of samples of agricultural tires. The adequacy of the model was assessed using the Nash-Sutcliffe efficiency coefficient.
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Смирнов, Петр, Petr Smirnov, Михаил Смирнов, Mihail Smirnov, Владимир Медведев e Vladimir Medvedev. "DESIGN AND RESULTS OF EXPERIMENTAL-INDUSTRIAL TESTS OF THE IMPROVED PLOW OF 14kN CLASS TRACTOR". Vestnik of Kazan State Agrarian University 14, n. 2 (29 luglio 2019): 117–22. http://dx.doi.org/10.12737/article_5d3e17376666e1.93769904.
Testo completoAbstract (sommario):
Most plows are of the small-width, used in personal subsidiary farms, were designed in Soviet times. In addition to the time-tested design, they also have hidden drawbacks that are associated with the aggregation by modern tractors, which are equipped with more wide-profile rear tires. For example, the currently produced modifications of tractors MTZ-80/82, YuMZ-6KL are equipped with tires 15.5R38.0 on the rear axle, the width of which, measured outside its deformation zone, depending on the pressure in them and the service life is about 38.4.. 40.3 cm. When the wheel with the above-mentioned tire is rolling on the furrow, opened by the plow PN 3-35 (the furrow width is 28-30 cm), substantial compaction inevitably occurs, which affects the quality of plowing and the increase in the total traction resistance of the unit. Accordingly, hectare consumption of fuel and lubricants increases. For example, according to theoretical calculations, when the value of the coefficient of bulk soil collapse q0 = 1.0 N/cm3, the traction resistance of the aggregate as a whole increases by 14.7%. We have proposed a modernized plow on the basis of PN 3-35 (patent No.2420938). The design of its frame allows the formation of trapezoidal sections with the first two parts. At the same time, the third frame, broadened by 5 cm, rolls off a layer of rectangular section. The shape of the frames was chosen from the condition of the mass transfer of the soil and the provision of agrotechnical requirements for field surface alignment. A plow was made and pilot tests were carried out. It showed that there is no compacted zone in the furrow, as well as noticeably reduced traction resistance.
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Myasishchev, D. G., D. N. Shostenko e А. V. Serebrennikov. "Fuel Consumption of a Straddle Forestry Tractor in Consideration of Stochastic Factors". Lesnoy Zhurnal (Forestry Journal), n. 5 (5 novembre 2020): 145–54. http://dx.doi.org/10.37482/0536-1036-2020-5-145-154.
Testo completoAbstract (sommario):
Currently, there is a tendency for creation a cross-functional tractor line of drawbar category. Everything is very practical and consistent from the perspective of the producer of such tractors. The number of modular units and assemblies is minimized, and the list of components is reduced. However, all this is acceptable up to a certain limit, which is outlined by the technological trail of the tractor being created and the specifics of its application. The article deals with a straddle forestry tractor of drawbar category of 6 kN. It is assumed that the tractor has a variety of trains of working bodies and machines, as well as a cargo bed on the pin-joint section. The cargo mode of the unitʼs movement is examined by a random microprofile under the wheels in tracks. The problem of statistical dynamics is solved. As an output process, a Laplace image is drawn for the hourly fuel consumption of the tractor engine. As an input process, a Laplace image is drawn for an external random action from the microprofile along the tracks. Herewith, the transfer function of the hourly fuel consumption is determined, which allows to estimate the spectral density of the tractor’s hourly consumption and the dispersion of the hourly consumption for the given microprofile of the tracks. In addition, using the correlation theory of random processes, one can estimate the mathematical expectation of the hourly fuel consumption during transport operations. In the final analysis, it is possible to solve the optimization problem. Namely, the choice of such undercarriage tires, which provide a minimum dispersion and mathematical expectation of the hourly fuel consumption of the transport unit. The situational combination comes down to the fact that an increase in the tire radius on one side increases the height of the center of gravity of the unit, which increases the hourly fuel consumption. On the other hand, an increase in the radius of the tire contributes to a reduction in the coefficient of rolling resistance of a wheel, and hence a decrease in fuel consumption. Thus, there is a problem of discrete optimization, namely, the choice of a tire design, in which the energy costs of the transport unit are minimized.
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Kambarov, B. A. "Dependence of the agrotech-nical clearance under the front axle of a cotton tractor with a wheel arrangement 4K4a on the dimensions of the pivot pin, the size of the tires of the steered wheels and the angles of their installation". Traktory i sel hozmashiny 84, n. 11 (15 novembre 2017): 36–39. http://dx.doi.org/10.17816/0321-4443-66347.
Testo completoAbstract (sommario):
At present, the concept of the transition of cotton energy to a four-wheeled power plant is being worked out in the republic. And it has, in comparison with the existing one, an additional potential for increasing productivity due to increasing the ranks of agricultural machinery. Cotton refers to high-growth technical crops, as at the stage of maximum biological development plants reach a height of 800...1250 mm. Minimal traumatization of the above-ground part of the plants during the processing of row spacing and loss of harvest during harvesting is largely due to the increased agrotechnical clearance of cotton-growing tractors. The modern cotton tractor has a scheme of propulsors with axle configuration of 3K2 and clearance of 820...830 mm under tubes of shafts of rear axles, due to the installation of additional final gears. The front steer axle is single-wheeled, it does not prevent the safe passage of plants under the tractor's framework. When developing a four-wheeled cotton tractor, a major problem is the provision of the required agro-technical clearance under the tube of the front axle. Preliminary studies have established that it is possible to change the agrotechnical clearance under the portal structure of the front axle by changing the length of the pivots of the pivot pins to the dimensions that provide the four-wheeled tractor with satisfactory flotation above the row of cotton. At the same time, it is necessary to take into account the known effect of the linear and angular dimensions of the front axle on the kinematic characteristics of the steering and the operation of the propulsors, in connection with which the analytical interrelation of the agrotechnical clearance under the front axle of the tractor with axle configuration 4K4a, the dimensions of the pivots of pivot pins, the dimensions of the steered wheels and the angles of their settings, allowing to calculate the amount of agrotechnical clearance under the beam of the front axle for different combinations of arguments that are included in this dependence. For example, it is established that with the length of the pivot shaft of the experimental front driving axle of 435 mm and the installation of 11.2-20, 11.2R20 and 11.2R24 tires, an agro technical clearance is provided within 826...877 mm, which meets the requirements of the technical specification for the cotton tractor.