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The article considers the dynamic processes of the oscillatory system «wagon - way», its mathematical model is formed and its features are established. The analysis of existing approaches to the consideration of the influence of dissipative forces on the stability of rolling stock is carried out, their shortcomings are revealed. When composing dynamic process equations, it is important to proceed from their exact expressions when considering kinetic and potential energy, i.e. to take into account the relationship between generalized coordinates, which will allow us to consider in detail the process of rolling stock oscillations. The zone of autoparametric resonance is found. It is established that dry friction forces do not interfere with parametric resonance. Dynamic equations are compiled taking into account the scattering forces arising in the contact points of the structural elements of the car. The influence of dry friction forces on the critical coefficient of parametric excitation is determined. The areas of dynamic instability of a car when moving along a railway track with different characteristics are determined. The features of the behavior of the system under the influence of dry friction forces are revealed. It is established that dry friction forces do not reduce the amplitude of bouncing and can lead to an increase in lateral pitching vibrations due to energy pumping.

Comparative bench tests of acoustic emission occurring during the interaction of the brake pad with a brake disc for the brake unit with a stationary brake pad and a brake unit with a floating brake pad are carried out. The floating brake pad, depending on the braking conditions, occupies an optimum position on the surface of the brake disc, while making movements of an oscillating nature around the turning axis that does not pass through its center of mass and parallel to the axis of rotation of the brake disc. The frequency range is determined in which there are noticeable differences in the acoustic emission of a brake unit with a floating brake pad and a stationary brake pad. The theory of fuzzy sets is used to analyze the acoustic emission perceived by the human hearing organs, which accompanies the interaction of the surfaces of a friction pair in the investigated frequency region. The results of a comparative analysis of the noise characteristics of the brake blocks under investigation are discussed. The spectra of the acoustic emission power are compared according to the obtained base of the expert evaluation of the noise power perceived by man.

The article considers phenomenological and modelling approach to researching of interaction of a deformable wheel and a plane of support, their advantages and disadvantages are mentioned. In the context of phenomenological approach the five methods of locomotive tangent tractive force calculation were considered. There certainly must be pseudo-creeping to let locomotive tangent tractive force do work and change the kinetic energy of a train in the point of wheel and rail contact. Locomotive tractive force experts calculate the power as product of the locomotive tangent tractive force and the velocity of translational motion of a train, although in fact the velocity of the point of force application must be assumed. It is applied to a wheel pair, then the velocity of this point must be used to calculate the locomotive power. According to this fact the locomotive power is found several tens of times reduced.

The reasons of a case-type vibration in the frictionless bearings in the assembled machine are studied. The method of identification of the radial clearances in the bearings without disassembling is suggested on the basis of the conducted measurements and analysis. The algorithm of vibrational prognostication of operating conditions of the frictionless bearings in the locomotive traction motors is suggested and grounded

The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

The mathematical model of traction drive Electric locomotive EP20 for research of dynamic processes in a mode of boxing is constructed. The natural frequencies and coefficients of the forms of the dynamic system are determined. The stability of the drive in relation to frictional self-oscillations is estimated. Dynamic loads in the drive elements at a single angular speed of wheel slip are calculated. The recommendations on increasing the dynamic qualities of the traction drive in the sliding mode are formulated.

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.

The issue of optimizing the use of lubricants to reduce the in-intensity wear of the wheels of traction rolling stock is considered in the work. The purpose of the work and the test objects are defined. The types of tests, their procedure, short description of tests, and compliance with the technical assignment and technical requirements are presented. Design work was carried out on the development of solid antifriction elements for lubricating the ridges of locomotive wheel pairs (hereinafter referred to as TAEL rods). Bench tests were carried out on a universal friction machine 2168 UMT «Unitrib», which models the contact interaction of the wheel with the rail when applying solid lubricant to the wheel ridge. The linear wear rate of the lubricating element and the friction moment were determined. Explutation tests were carried out on the basis of traction rolling stock of the series VL80, 2TE25KM, ChME3. Such indicators as average intensity of development of cores of TAEL and lubricant cores and average intensity of wear of crests of wheels were defined. The results of laboratory bench-out and operational tests of TAEL rods were obtained in accordance with the order of admission of lubricating materials for wheel-rail contact for use in locomotive combs operated on the railways of the Russian Federation. Operational tests of traction rolling stock were carried out at the landfills of the North Caucasus, South-Eastern and Volga Railways. During the performance test period, the following indicators were monitored: assessment of the impact of TAEL on the wear of co-forest steam ridges, assessment of the actual resource of TAEL production, assessment of the functional capabilities of TAEL rods. According to the test results, the developed TAEL rods received permission to use Russian Railways for the infrastructure. At the same time, the wear rate of the ridges of the wheel pairs of locomotives equipped with TAEL in comparison with the standard rods decreased to 50 %.

The article is devoted to the experimental study of the force interaction of the working elements of a disc brake in order to establish the dependence of the coefficient of static friction, taken as a criterion for the potential frictional properties of the friction unit, on the pressing force of the brake linings to the brake disc and the coefficient of mutual overlap. The experiments were performed on a full-scale stand, the basis of which is an electric drive with a power of 75.0 kW and a full-scale disc brake of the LT-10 tram. The stand allows to measure the static friction force under conditions of real forces, pressures, geometry of the contact area, as well as the coefficient of mutual overlap. TR119 and UT22-B were taken as friction materials for brake linings, in the first of which, according to the characteristics declared by the manufacturer, the coefficient of friction decreases with increasing temperature, in the second it increases. During the experiments, these materials worked in a pair of friction with the material steel 35, from which the brake disc is made. The experimental results were processed using the methods of mathematical statistics and presented in graphical form. It is shown that in the range of loads realized during braking, the stress-strain state of the contact area of the working elements of the disc brake according to the criterion of microstrains corresponds to an unsaturated elastic contact. This type of contact is typical for the studied overlap coefficients (0,33; 0,66; 0,98). It was found that with an increase in the pressing force of the brake linings to the brake disc, the static friction coefficient tends to decrease, and with an increase in the overlap coefficient, an increase in the static friction coefficient is observed for all specified values of the pressing force. At the same time, the UT22-V material is characterized by lower values of the coefficient of static friction compared to the TR119 material. Field of application of the results: development and design of advanced designs of disc brakes.

The traffic speed increasing on the railways makes strict requirements to the supporting and supporting structures of the contact network, as well as to the parameters and indicators of the contact suspension. The presence of dry friction in the cantilever attachment points indicates a negative effect on the accuracy of adjusting the wires of the contact suspension and on its parameters. The article presents the results of studies of the dry friction value in the console fastening points depending on the type of the contact suspension and suggests a method for reducing friction in the console attachment points. The results of calculations of the effect of friction in the console attachment points on the tension variation along the length of the anchor section are presented.

The results of the study the strength characteristics of loess loam under triaxial when exposed vibrodynamic load of high-speed trains. Research carried out on triaxial vibration, based on the principle of operation of the plant simulation vibrodynamic exposure to periodic changes in hydrostatic pressure in the working chamber triaxial. The experimental values of specific cohesion and angle of internal friction, and the values of their relative decline under the influence of vibrodynamic load.

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.

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 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 .