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The results of the pilot studies to increase the resource of the wheel of the rail stock are presented. The electroslag melting is used to restore the surface rolling and the wheel cam of the cars and locs wheels. The experimental research adopts its perspective.

The wheelset and its components (the axle and the wheel) are subject to technical regulation. Therefore, in order to establish the assigned service life in accordance with TRCU 001/2011 (Technical Regulations of the Customs Union) and the examination frequency taking into account the durability parameters of rolling stock components in accordance with VNIIZhT RD 27.05.01-2017, it is necessary to assess the operational loading obtained from the running testing results, with respect to the part strength characteristics which are calculated during the bench tests. At present, to estimate the stress-strain state (SSS) in various machine-building structures, the strain measurement method is widely used, which allows to assess their performance with high accuracy. However, determining the SSS of a wheelset is not only a difficult task due to the constant rotation and movement of the wheelset relative to the bogie, but also expensive due to the employment of special non-contact measuring systems. Development of a dynamic model using modern software systems allows determination the stress-strain state of the wheelset elements by creating dynamic models as a system of perfectly rigid and elastic bodies connected by strength members and hinges. To confirm the adequacy of the parameters obtained in the simulation, verification is carried out according to the results of running dynamic strength tests. Thus, using the obtained model of the rolling stock and the track it is possible to make life and durability assessment as well as optimize the main rolling stock components. On the example of a freight gondola car model, a diagram of the dependence of dynamic stress amplitude distribution on the frequency of the occurrence in the wheel has been obtained, and considering the results of the earlier bench tests of standard specimens and full-scale wheels the period has been determined for durability from the moment of crack initiation in the wheel up to its fracture, as well as the assessment of the safety factor for durability is given.

The article presents the results of studies of the effect of material properties and wheel failures on the process of their machining on the on the car wheel lathe. Developed by complex criterion that takes into account the effect of various factors on the allowable cutting speed. The proposed method for assessing the machinability of cutting wheels through additive criteria. The quantitative characteristics of the machinability of cutting are obtained, taking into account the macroscopic imprecision of the geometric shape, defects in the thermomechanical interaction of the wheel, brake pad and rail, surface defects of the rim, work hardening and the presence of zones of increased hardness. The results can be used in the development of methods to reduce the consumption of carbide cutting tools for machining parts of rolling stock with operational defects.

In article are considered standard technologies of ultrasonic inspection of under-hub parts of press-fitted wheelset axles accordingly to existing regulations: GD (Guidance Document) 07.09-97 and STO (Standard of the Organization) Russian Railways 1.11.002-2008, and proposed improve-ment measures of nondestructive inspection that are confirmed by calculation and experimentally

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 results of mathematical modeling of the heating process of the wheel material during braking mode of the locomotive are presented in article. The results can be used to calculate the temperature change for any point of the wheel during the braking operation.

The article noted the need to improve the technology of repair locomotive wheelsets. We propose a model describing the process of machining tread on milling machines based on thermo-mechanical approach to cutting metal. On the basis of the model is a method for analytical determination of the forces of milling, the temperature front and rear surfaces of the carbides. Presented results of the comparison of experimental data and data obtained analytically.

Considered forced oscillations of four-axle vehicle with dual spring suspension. It is obtained that the movement system with six degrees of freedom with sufficient accuracy can be represented by a system with two degrees of freedom. Therefore, the vehicle body has two degrees of freedom: lateral skidding and wobbling, Bouncing and galloping trucks will be neglected. The total number of degrees of freedom of the model equal to two. The method, which leads to a closed solution of the forced oscillation. Defined. That tends and to (n = 1, 2,…), the amplitude of the oscillations will be unlimited. Therefore, the parameters k1, k2 and T must be selected on the basis of required values of amplitudes. As a result of research compiled by the differential equation of motion of the system and obtained analytical solution for the case of external piecewise constant driving force.

Subject of researches is determination and the justification of mathematical characteristics of motion of a railway wheel adequately reflecting the gear of its interaction with a rail. The activity purpose is adaptation of fundamental positions of the cycloidal curves reflecting motion of a circle to motion of conditional points of topological circles of section of a shroud of a railway wheel, having a difficult structure. The activity methodology is constructed on study and systematisation of fundamental investigations in the field of geometry, mathematics and mechanics of idealised motion of a circle in which basis mathematical properties of cycloidal curves are put. The model of motion of a wheel of a railway mounted axle (with immovable wheels on an axis) in which basis are put kinematic and mechanical properties golonomnykh systems is fetched. Following general golonomnykh, fundamental mathematical properties of system, analytical relations and ratio of kinematic parametres of a forward speed of railway vehicles and speed of interaction of wheels with rails which allow to supplement methodology of thrust calculations at us and in other countries are installed. By the current moment time in domestic practice use tens various formulas which actuate a component of linear speed of motion, instead of speed of interaction of wheels with rails, taking into account their physical and geometric parametres. Linear (translational) speed of motion of a wheel not absolutely adequately reflects the gear of interaction of wheels of railway vehicles with rails. The fundamental theory of cycloidal curves gives the chance is proved to normalise analytically speed motion of railway vehicles of various types, to designers and founders it a priori to form constructional and technology - economic characteristics warranting reliability, life and overall performance of the equipment dolly parts, reducing risk of a traffic security of trains.

In article the questions connected with cranking of bandages on the wheel center arising because of weakening of interference fit. Authors suggest to consider the possibility of use of conic interference fit instead of cylindrical. For this purpose considered possible options for manufacturing the proposed connection. Revealed of the optimum angles conjugation aimed at a uniform distribution of metal bandage volume. Designed wheel design can be widely used in traction rolling stock. The result is reduced the duration of the repair of locomotives associated with the replacement and constriction bandages.

The article deals with the controlled motion of electric locomotive 2ЭС5К «Ermak» in the small radius curves. To implement the management offered to enter into the composition of each axlebox node of wheels pair additional unit - a special carriage. Analyzed two variants the control electric locomotive in the small radius curves. The conclusion the most efficiency control is control of the first wheels pair.

The subject of the study is the process of applying optical technologies for non-contact measurements of geometric parameters of a wagon wheelset during operation and repair. The purpose of the study is to study the methods of field testing of technologies for controlling the geometric parameters of car parts using an optical rangefinder, with mutual verification of the results obtained using numerical modeling using three-dimensional digital models of objects and measuring instruments. As a result of the study, experimental and calculated dependences of the optical sensor readings were obtained during the change in the relative position of the measuring object (wheelset) and the rangefinder. Two laser triangulation rangefinders were used for field tests. For numerical simulation, a program was created that allows generating a three-dimensional model of the rolling surface of a wheelset consisting of a set of points belonging to the surface of rotation. The simulation consists in finding the intersection points of a line defined using the coordinates of the point of the radiation source in space and the guiding vector with the model of the skating surface. After the calculations, the result is given in the form of a table with calculated ranges and visualized as projections of a three-dimensional wire model of a wheel and a rangefinder beam. Visualization of the numerical modeling process is important to avoid misinterpretation of the calculation results and to verify compliance with the physical meaning of the numerical data obtained during modeling. Comparison of graphs shows the convergence of the results and sufficient accuracy of numerical models and techniques that can be used in the future to plan full-scale tests of the designed techniques and equipment for dimensional control of railway car parts.

The results of the experimental study of the termal cycle of many-electrode welding of the solid wheel`s comb and its influences in work upon structurization in zone of the termal influence are presented.

The results of experimental research on the diagnostic features of wheel-motor unit assemblies dependence on the speed of the wheel-pair. The parameters of the distribution of diagnostic features are given and a method of providing higher reliability of diagnostics of electric train WMU is provided

The paper is vibration investigation in a case of guiding of railroad vehicle in curves with low radius. Experimental methods. Examine results of the investigation of vibrations on box bearing of railroad locomotive in a case of mountain trucking with large count of curves with low radius. It is show, that in a case of locomotive guiding in a low radius curves a pseudo-random vibration arise. The level of the pseudo-random vibration in a low radius curves exceeds the vibration in the rail joint, but vibration in the guiding is semi continuous. In a case of locomotive working, also the harmonics of gearing is shown. The spectral density of vibration accelerations is presented in a three-dimensional form, coded in color on a two-dimensional time-frequency diagram for estimating the vibration spectra and their probable sources.

Article is devoted to one of actual problems – to definition of the rational hardness ratio of wheel and rail. The mathematical model of wear process of friction pair «wheel – rail» is developed. Results of researches on intensity of wear process of wheel and rail are presented.

The analysis of the operational efficiency of freight cars circulating on the Russian railways, shows a lack of basic truck models 18-100 and its modifications and foreign counterparts. We propose a method for increasing the efficiency of the dynamic properties of the freight car with a cart, which has a new design of spring suspension, based on the principle of compensation of external disturbances and presented its advantages.

In this paper the authors propose to consider the peculiarities of making mathematical models of rolling stock and its dynamic behavior when driving on irregular resilience railway line in the longitudinal direction. We present a qualitative and empirical analyzes of longitudinal resilience railway railway. In conclusion, given the conclusion, on the basis of its proposed further consideration of mathematical aspects of the above solutions of systems of differential equations of motion of the rolling stock on irregular resilience way.

In article the question about possibility of extension of service life of carriage wheels by influence on technological parameters of restoration of their driving profile is considered. The correlation analysis of statistical data on volumes of machining and the size of defects on a driving surface of the wheels coming to repair is made. The mechanism of purpose of an allowance for machining of a driving profile of a wheel which will allow to reduce an unreasonable consumption of metal of a rim of a wheel in shaving is offered.

The article sets out the methodology of the study of a rigid mathematical model describing locomotive wheel and rail interaction, taking into account the hypothesis f. Carter. On the basis of the application of the theorem N.A. Tikhonova derived the differential equation for determining the rate of slippage of wheel pair on Rails. Determine the time dependence for the establishment of a process of kinematic slippage of wheel pair on Rails from the wheel speeds and locomotive, from inertial characteristics of trains and the wheel, as well as the coefficient of creep, annexed to the torque of wheel pair and the State of the surfaces of the Rails.

The evaluation of the stress state of the elastic pad rim wheel set new design and the substantiation method of its calculation.

The wheel-motor unit of freight electric locomotives is characterized by the dynamic effect of a wide range of the disturbances due to irregularities in the track. This is one of the main reasons for the high damageability of the gear casings, observed recently, and it indicates the need to improve its design. The proposed design changes for the casing should be directly related to the assessment of the level of the dynamic loading during its operation. The results of the numerical and experimental determination of the natural frequencies of metal casings of traction gear used on electric locomotives of the VL85 and 2 (3) ES5K series are presented. For the numerical determination of the natural frequencies of the enclosures, a modal calculation of the solid model of the enclosure in the Ansys Workbench software environment was performed using the finite element method. A comparative analysis of the distribution of deformation fields in the sidewalls of the casing for a casing that is not fixed to the traction engine and rigidly fixed is carried out. For the experimental evaluation of the natural frequencies of the gear casings, a vibration transducer fixed on the casing was used; the method of excitation of vibrations with a single blow was used to excite vibration. As the result of the experiment, the peak values of vibration acceleration were revealed at some frequencies, which testifies to the emerging resonance phenomena for the casing, and the values of such dynamic parameters for the casing design as natural frequency, Q-factor of the oscillating system, logarithmic damping decrement, relaxation time were obtained. The values of the natural frequencies of the gear housing are obtained by solving a system of Lagrange differential equations of the second kind. The mathematical model of the considered mechanical system created for this purpose takes into account the elastic nature of the casing attachment to the traction motor. The values of the frequencies of the natural vibrations of the gear housing obtained make it possible to evaluate its dynamic loading at the frequencies close to the resonant ones.

In the article suggests a changing the algorithm of the rectifier-inverter converter electric locomotive VL85. This will allow the individuallyto regulatevoltageon traction engines. In this case willpreserve a singlecentralized system ofcontrol of allelectricconverters. The proposed solutions may be used for liquidation started spinning of wheel locomotive. Tractive force the remaining wheelsets will not decrease.

The subject of the study is the theoretical and practical aspects of the application of optical technologies for non-contact measurements of geometric parameters of a wagon wheelset during operation and repair. The purpose of the study is to develop methods and technologies for monitoring geometric parameters of car parts using an optical linear scanner, as well as a method for processing the results of field tests of the results of the application of optical control technologies. The article analyzes the problems of application of standardized methods of technical condition monitoring using manual measuring and control tools in the context of the adopted technology of maintenance and operation of freight cars. As a result of the study, a review of the state of the issue of the use of optical control techniques on the railway was carried out, the strengths and weaknesses of various options for the implementation of measurement techniques were identified and a methodology and a computer program for automating the creation of a digital standard of the object under study (the profile of the longitudinal section of the rolling surface of the wheelset) were developed. Using a digital two-dimensional image of the shadow pattern of the wheel profile, the coordinates of the points of the contour line of the section of the volumetric wheel in the area of the rolling surface are calculated. To determine the coordinates of the envelope of the section, a step function is used, as close as possible to the chiaroscuro image of the wheel contour. After image processing, the result is output by the program in the form of a table with the calculated coordinates of the profile section and visualized using the wheel profile synthesized by coordinates in the program window. The accuracy of the technique used depends on the resolution of the image obtained by the linear scanner. The methodology and program can be used in the future for field tests of the designed equipment for dimensional control of car parts.

The article presents the results of modeling the force fields in the elements of the wheel-motor unit of the electric locomotive 2ES10. The mathematical model is obtained on the basis of the Lagrange equations of the ΙΙ kind. A design scheme for the study of the dynamic behavior of the wheel-motor unit is presented. Expressions for the deflection of the elastic elements of the traction motor suspension, elastic and dissipative forces are given. A method for determining the vector force field at the articulation site of the bracket and thrust suspension TEM is proposed.