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The article presents the results of the study of the influence of deviations of certain design parameters of bogie from established normative values on a relative offset from the crests of wheel pair in mezhdurelsovom space of railway transport. Such deviations occur in the process of the gradual wear of moving parts in real-world conditions of rolling stock and lead to a change of kinematic parameters of bogie. An analysis of dependence of lateral displacement relative to the wheelset of railway track from the difference between the diameters of the tapered surfaces of wheelset, skating from lack of alignment of wheelsets and difference coefficients rigidity of springs of bogie. The proposed mathematical model allows to not only diagnose technical condition of wagon bogies during their movements on the straight section of railway track, but also forecast the rolling stock maintenance dates the whole on the basis of position measurements of wheel pairs regarding railway track.

The article carried out a comparison of the magnitude of the crest of the pressure forces on the rail in the curve sections of track and locomotives TG16 TG16M.

The article proposes methodology for assessing the power loss in motor thrust bearings, the nodes of box, traction gear transmission. Revealed dependence between the power losses, the diameter of the tire wheel pair and the speed characteristic of the wheel-motor block. The results can be used to assess the technical condition and energy efficiency of traction rolling stock of Railways.

In this article, with the help of software, the relationship between the structure of the material of the brake pad and the temperature distribution of thermal stress on it is established. Spatio-temporal distributions of thermal stresses were analytically determined for the surface layer of the friction element based on the model of a three-section brake pad with non-fixed edges. At present, shoe brake is widely used for freight trains. It converts dynamic energy into thermal energy using the friction between the pads and the wheel, and then dissipates the thermal energy through a heat exchanger. This process includes heat transfer, design features, mechanical characteristics, material properties and other. The article pays special attention to the brake pad pressure, braking mode, brake pad material and other factors. Modeling of thermal effects is the most important in the design of vehicle parts and assemblies. Thermal research is an important step in the study of braking systems namely railway vehicles, where it is necessary to breakе large masses, since the thermal load on the braked railway wheel prevails compared to other types of loads. In this paper, the thermal stress on the friction element of the shoe during braking is investigated. In frictional braking, the process of friction between the brake pad and the wheel occurs at the points of actual contact. The heat flow from the points of actual contact spreads over the entire geometric area of the block.

The cranking of the bandages in service leads to an earlier replacement of the bandage than the pawned resource, which entails both an increase in maintenance costs and a long, simple locomotive for repair. The article shows the main factors that have a significant effect on the strength of the «wheel center - bandage» connection. Particular attention is paid to the mechanical properties of materials. The calculation of the reduction of the contact pressure from the heating of the bandage has been carried out, both for the new and for the worn out. New materials for manufacturing of bandage wheels are considered. It was found that the hardness of the materials can have a significant effect on the strength of the bandage fit to the wheel center. Preliminary calculations of the influence of hardness on the strength of the joint are carried out.The analysis of the influence of the mechanical properties of banding wheel materials on the strength of the joint can be used in the improvement of new materials in the manufacture of bandage wheels and in the development of technology for the formation of wheel sets of locomotives, which in turn will improve the efficiency of wheel sets of lo-comotives.

The article sets the task of determining the level of dynamic loading in the «trolley-leash-traction motor» subsystem to reduce the dynamic impact in the «locomotive-path» system. The model of vertical vibrations of traction rolling stock, obtained on the basis of the Lagrange equation of the second kind, in the form of a system of fourteen differential equations allows us to estimate the loading of locomotive units in operation, integrated using the MathCAD application package. The approximation of random disturbances using the spectral density of the path irregularity of Professor A. I. Belyaev is chosen as the spectral density of random disturbances. A more detailed design scheme of the crew has been compiled and in order to simplify the calculation within the engineering error, a single-mass discrete model of the path is used. Entering symmetric coordinates allows us to obtain from the original system of differential equations a simplified system with characteristic equations with simple roots, therefore, the natural oscillation frequencies of the bouncing of the body, trolley and wheelset will be determined with minimal error. The transfer function is determined by Kramer's formulas. With the help of a computer, the values are calculated and graphs of the amplitude-frequency characteristics of vertical movements, maximum accelerations of the body, trolley, traction motor and wheelset of the electric locomotive in question are constructed. A comparative analysis of the calculation results and empirical data is carried out. Based on a comparative analysis, it can be argued that the considered mathematical model of vibrations of the electric locomotive 2ES6 «Sinara» is adequate and allows determining the dynamic loading of the locomotive for the entire range of operating speeds. The task of changing the existing design of the suspension system of the traction electric motor of the electric locomotive in question and the mathematical analysis of the vibrations of its nodes in further research is set.

The article deals with the issue of the formation of defects of thermomechanical origin (sliders) on the rolling surface of wagon wheels during their skidding along the rail, since such defects affect traffic safety to a greater extent. In addition, such defects on the tread surface of the wheel are difficult to eliminate in the repair industry. It is known that the slider is formed when the wheel is jammed and its translational movement (sliding) along the rail, the so-called skid. As a result, in the area of contact between the wheel and the rail, intensive wear of the wheel material is observed, as a softer element, and a wear area (slider) is formed. The slider is evaluated by such a parameter as the depth relative to the wheel tread. An algorithm for calculating the depth of the slider is given under the condition of a short-term movement of the wheel along the rail skidding. The initial data were determined and a calculation was made with the construction of graphs that reflect the dependence of the slider depth on the speed of the rolling stock and the load on the axle of the wheelset during short-term skidding. A technique for calculating the maximum temperatures in a pair of sliding friction "wheel-rail" is described. The values of the maximum temperatures in the contact patch are calculated when the wheel moves along the rail skidding. Based on the results of the calculations, graphs of changes in the maximum temperatures on the wheel tread surface in the area of friction on the rail under various operating conditions were plotted. An assessment is made of the possibility of indirect determination of the depth of the hardened metal layer in the area of the slider, depending on its dimensions, measured when the wheelset was received for repair.

The article presents an analysis of the failures of the mechanical components of the mainline electric locomotives 2ES6 «Sinara» in operation at the landfill of the West Siberian Railway, the causes and consequences of failures of the most vulnerable nodes are determined. The analysis of failures of the mechanical components showed that a significant share of them falls on the components of the wheel-motor unit of the locomotive. The analysis of the design features of the crew part is carried out. The main structural difference of suspension is the absence of leaf springs in the axle box stage, which were widely used on electric locomotives of previous generations. In the body stage, helical springs (Flexicoil) are used instead of the cradle suspension. The connection of the traction motor with the trolley frame is a pendulum. The suspension of the traction motor to the trolley frame is carried out through a leash. When considering the vibrations of railway carriages, it is customary to represent the locomotive and the track as a single mechanical system. The task of forming a mathematical model of the «electric locomotive - path» system is set and a mathematical model of vertical vibrations of an electric locomotive is formed taking into account the dynamics of wheel-motor blocks based on the Lagrange equation of the second kind in the form of a matrix equation, which allows us to assess the loading of mechanical components in operation. The mathematical model represents a system of differential equations in which six equations determine the fluctuations of the bouncing and galloping of the body and trolleys, four - the galloping of wheel-motor blocks, four - the bouncing of wheel pairs together with the reduced mass of the track. The obtained mathematical model makes it possible to determine the level of dynamic loading of the components of the mechanical part of the electric locomotive 2ES6 «Sinara» by integrating the matrix equation using the MathCAD application package.

For a radical solution of the issue of extending the service life of wheelsets of the freight cars, it is proposed to weld not only serviceable wheels, but also wheels to be pressed against an unacceptable rim thickness. It is shown that in multilayer surfacing, the possibility of obtaining high quality metal becomes more difficult, and heating of a thin rim can have an adverse effect on the gap between the inner surfaces of the wheels. The purpose of the work is to optimize the technological parameters of the multi-electrode surfacing mode, determine the amount of warpage of the wheel disk and study the quality of the deposited metal during operational tests of wheel sets. Experimental surfacing was carried out on the optimal parameters of the multi-electrode process, and a method for measuring the value of wheel warping in conditions of multilayer surfacing was proposed. The results of studies on the influence of the multi-electrode surfacing process on the metal structure and wheel warping are presented. It is shown that under the optimal surfacing mode, favorable conditions are created for obtaining fine-grained structures in the near-seamed zone. Field tests of the freight cars wheel sets were carried out to determine the efficiency and reliability of the method of automatic multi-electrode surfacing of the wheel rim. The task of the tests was a comparative assessment of the resistance of the wheels under study to defects and wear. The implementation of the task involved obtaining data for the wheel sets being researched on the number of cases of wheel failure due to the insufficient quality of the welded surfacing metal. It was found that wheel warping does not cause any dangers that threaten traffic safety, and the weld metal has the necessary resistance to cracking under the action of operational loads.

In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry.

The analysis of the development of the wheels increased hardness on the example of certain manufacturers, and changing regulatory and technical documentation for production (GOST). A mathematical analysis of the comparison operation wheelsets normal hardness of the wheel pairs of high hardness, based on the receipt of freight wagons from production to unscheduled maintenance. For comparison methods were used: Cramer - Welch and Laplace function. The estimation of av-erage mileage of cars on different types of wheel sets of freight cars and production technology. Developed the basic advantages of high hardness wheelsets.

The article is devoted to the problem of elimination of thermomechanical damage on the surface of rolling wheel pairs of cars, which arising from the use of brake shoes to reduce their speed. A new design of the brake shoe equipped with electromagnets, which provides braking without jamming the wheel pair. Article contains calculation of the braking force and the provide slowdown .

The article discusses the design features of the mechanical and crew parts of the passenger electric locomotive DC EP2K, which directly have or causes an impact on the rail track. The purpose of the work is to consider the features of the interaction of the crew and the track when moving this electric locomotive in small radius curves by evaluating the forces arising in the "wheel-rail" contact of the three-axle bogies of the EP2K electric locomotive under these conditions. The need to solve such a problem is caused by the results of the analysis of statistical data on the wear of the ridges of the wheels of EP2K electric locomotives. These electric locomotives are operated at the united railway landfill, where there are a large number of curved sections, including curves of small radius. To achieve this goal, a design scheme of a three-axle trolley of an EP2K electric locomotive has been compiled, which allows a quantitative assessment of the forces acting in contact with the wheel ridges with the relay heads. According to the calculation scheme, a system of equations has been compiled, the solution of which makes it possible to estimate the forces between the ridge and the inner face of the rail head. Based on the results of the calculation of the guiding forces of the wheel pairs of the three-axle bogie of the EP2K electric locomotive, it is concluded that the values of the guiding force acting on the second wheel pair are comparable to the forces acting on the first and third wheel pairs, and in some variants even exceed the values of these forces. The obtained results can be used for further research on the development of measures aimed at reducing the wear of the ridges of the wheels of electric locomotives of the EP2K series under operating conditions.

The article describes three variants of the mathematical model of the sensitivity function of the magnetoinduction sensor for assessing the influence of various sensor parameters in the electromechanical system «wheel - rail - magnetoinduction sensor» for diagnosing the technical condition of the rolling surface of the rolling wheels of rolling stock in the process of its movement over the sensor. An example of an algorithm for identifying defects located on the surface of the wheel rolling circle is described. The proposed multi-vector mathematical model allows simulating various defects on the rolling surface of the wheel, developing and testing new algorithms for processing the output signal of the sensor on the basis of modern hardware and software. The implemented defect identification algorithm is based on the property of the centrally symmetric form of the sensitivity function of the magnetoinduction sensor and the allocation of a useful signal corresponding to a certain type of defect, based on the application of a mutual correlation function and the assessment of its maximum and minimum values in comparison with the specified thresholds and confidence intervals. The main requirement for the implementation of the model is the uniform movement of the train above the sensor along a straight section of the rail track. This article discusses only one of the possible digital signal processing algorithms, but the proposed model allows us to compare the efficiency of other possible algorithms identification of defects in the rolling surface of wheelsets. The developed model confirms the prospects of using magnetic induction sensors for identification of not only visible, but also hidden defects on the rolling surface of the wheel in the process of movement of the train.

To improve the accuracy of the diagnosis of the technical condition of rolling stock, it is necessary to develop new algorithms for the digital processing of signals coming from sensors at the time of the passage of the axes of wheeled pairs of wagon carts during the uniform movement of the train on the straight section of the railway track. The use of modern mathematical application software packages to model digital-based data processing algorithms reduces the cost and time of developing automated systems to diagnose the technical condition of the rolling stock of railways. To assess the accuracy of the fixation by the magneto-induction sensor of the moment of passage of wheel pairs axly, an asthigmatic model is proposed, allowing to investigate not only the energy properties of the sensor, but also the shape of the output signal, taking into account the real dimensions of its magnetic core. The developed model allows you to classify the pore. The developed model allows to classify the order of astigmatism model magnetoinduction sensor based on a set of discrete virtual sensors

The article presents the results of research of a point magneto-induction sensor based on a mathematical model, which allows you to increase the reliability of automated systems for diagnosing technical condition rolling stock in the course of train movement by improvement the accuracy of the initial information, that is, the moments of fixation passing of wheelset axles over magneto-induction sensors. At the first stage of developing a stigmatic mathematical model the analytical dependence of the value of the magnetic flux in the magnetic core and the output EMF value on resistance of the air gap between the sensor and the wheel crest. At the second stage of development of the mathematical model found time dependence of the magnetic resistance of the air gap between the core of the magneto-induction sensor and the comb wheels of a railway car moving along a straight track at a constant speed. On the basis of application the developed stigmatic model allows evaluating the energy parameters of magneto-induction sensors depending on the properties of modern magnetic materials. The simulation results showed that the MMF value is constant the magnet determines the main parameters of magneto-induction sensors, so the use of modern magnets based on rare earth they allow to eliminate the traditional disadvantage of outdated types of magneto-induction sensors, that is, to reduce their size and weight. The application of the proposed stigmatic model expands the scope of possible solutions to extreme problems for selection and justification parameters of magneto-induction sensors, helps to improve the accuracy of systems for diagnosing the technical condition of the car fleet and traffic safety on railway transport.