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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 purpose of this work is to determine the causes of cracks in the frame of traction motors of electric locomotives. An analysis of the statistics of detecting cracks in the frame of NB-514 traction motors at the Eastern testing area is presented, showing that every third frame in operation has cracks. The method of mathematical modeling on a computer with the use of FEM was used. It is noted that carrying out measurements in the crack initiation zone by the tensometric method is practically impossible due to the geometry of the frame. The results of mathematical modeling of mechanical stresses arising in the frame of the NB-514 traction motor during its uneven heating to temperatures characteristic of the hourly mode of operation of the traction motor are considered. It is shown that mechanical stresses arising only due to the temperature difference between the ambient air and the windings of the main and additional poles of the traction motor can reach 100 MPa. Variants of changing the design of the ventilation windows of the frame are proposed to reduce the magnitude of temperature stresses with a constant area of the ventilation openings. When correcting the shape of the ventilation windows of the traction motor frame, these voltages can be reduced to 76 MPa. It was concluded that one of the main reasons for the formation of cracks in the frame of traction motors are cyclically repeating temperature stresses, which is especially important for electric locomotives operating on mountain pass sections in the pushing mode. It is noted that the appearance of mechanical stresses in the backbone of the traction motor also depends on vibrations arising from the path and operation of the gear train, as well as on the variable part of the magnetic field of the motor, which are not currently studied in detail.

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

The deterministic evaluation of the durability of railway rolling stock structures according to fatigue safety factors, established by regulatory requirements, does not fully take into account the random nature of loads that cause the accumulation of fatigue damages, the operation rate (operating time), does not allow to evaluate the operating life and its depletion over the service lifetime. At the same time, with the development of heavy and high-speed traffic, as well as due to the introduction of technical regulations, the task to evaluate and substantiate the assigned service lifetime and operating life of railway vehicles are becoming more important. The subject of the study, the results of which are presented in this article, was the fatigue strength of elements of locomotive basic parts. The purpose of the work was the prediction of their limit state by the operating life of critical elements. In the present work, design and experimental studies have been performed with running dynamic and strength tests of the locomotive in the entire range of operating speeds of its running, determining the stress-strain state of structures using strain-gauge methods, calculating safety factors with the probabilistic estimate of the fatigue strength of parts. According to results obtained, the influence of the operation loading performance on the fatigue strength margin and its depletion during the element operating life is shown. According to the results of this work, it can be concluded that main indicators of the strength, operating life and service lifetime of the locomotive make it possible to compare and link their key parameters for the subsequent analysis, substantiation, rating and control of safe operating life of railway equipment.

As a result of tension increase and significantly loads on the overhead contact lines, there is need to research the tensile stress value for contact and messenger wires. In this paper, the author reviewed the wires operation conditions concerning the thermo-mechanical load. The author has analyzed the results of contact wires low-temperature creep tests. The real rate of contact wires creep is as appropriate as the standard values. At the same time, copper wire elongation is faster than bronze. The author has provided results about contact and messenger wires ultimate tensile stress tests, heated at different temperatures. The ultimate tensile stress rate for the copper and bronze contact wires is reducing by 9 % with temperatures increasing. The ultimate tensile stress rate for the cop-per messenger wires is reducing by 11 %, for the bronze wires - by 4 %, with rising temperatures to 150 °С. Test results have shown that heating of copper wires to temperatures above 90 °С and bronze wires to temperatures above 120 °С leads to a significant immediate reduction of strength. Working conditions for the overhead contact lines wires are close to the critical one. It is not sufficient for reliable and safe operation Author offers to modify regulatory requirements for contact and mes-senger wires concerning permissible heating and also not to divide short-term and long-term heat-ing and only to leave permissible heating.

The article discusses the possibility of extending the service life of passenger cars. The analysis of the state of the passenger car fleet has established that the rate of replenishment of reserved cars has been reduced by more than 40 % over the past 10 years, therefore, it is possible to ensure coverage and replenishment of the retirement of rolling stock of this type after the expiration of the standard service life only by extending the service life of existing cars by carrying out capital repairs with the establishment of a new standard service life. When analyzing the power frame of a reserved seat passenger car, it was found that the greatest static and dynamic loads are perceived by its center beam. It is precisely because of the stresses arising in it that an assessment is formed of the further possibility of operating a car both during its life cycle and further use in diagnostics for the possibility of assigning a new service life to it during overhaul repairs. Studies of a number of elements of center beams cut from passenger cars that have expired the standard period have established that the main characteristics of the metal meet the requirements of safety standards, this indicates that the safety margin and resource inherent in them has not been fully depleted. In the study of the presence of residual stresses that have arisen in the elements cut from the ridge beams, depending on the depth of etching carried out according to the method of N. N. Davidenkov in accordance with the TSNIITmash methodology, the most vulnerable and dangerous places of corrosion that require more careful control during the car maintenance and scheduled preventive repairs were identified. In order to reduce the development of residual stresses and the corrosive effect on the load-bearing frame of a second-class car, recommendations and technological operations have been developed for strengthening the ridge beam by the method of shot-blasting with the formation of a uniform fine-pored structure, which ensures uniform application of paint and varnish coating.

Issues related to the wear of the rail and wheel tread of a locomotive are always of great interest to both operational services and scientists. Knowledge of the influence of technical and operational factors on the intensity of wear of the materials of the contacting bodies would save material and financial resources. The proposed article is devoted to determining one of these parameters, namely, the depth of indentation of the material of the rail head into the material of the wheel rim flange. The force interaction of the bandage crest and the rail head occurs mainly at the level of irregularities in the contact area. The wear of the material of the contacting bodies will be determined by the depth of penetration of irregularities in the contact area and the speed of relative slip. An important parameter for assessing the magnitude and nature of wear is the relative penetration depth of the contacting bodies. In this case, the magnitude of the collapse of one of the contacting bodies is equal to the depth of penetration of another body into it. Calculations of the main radii of curvature of the surfaces of the rail head and bandage crest at the point of their contact are made, and the dimensions of the contact area are determined. As a result, expressions were obtained for calculating the depth of mutual penetration of the materials of the shroud crest and the rail head. The rail head material has a deeper penetration into the shroud tongue material. The force contact between the bandage crest and the rail occurs mainly within the limits of plastic deformation of their materials. Formulas are obtained for determining the magnitude of the approach of the contacting bodies and the highest normal stress in the contact zone. An estimate of the values of the collapse of the material of the rail head and the bandage crest was made, which makes it possible to judge the percentage of their wear. With force contact, the wear of the wheel rim flange is much higher than the wear of the rail head.

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.

The actual process of interaction of pantograph with catenary associated with random processes. The main factors affecting the pantograph are vibrations of the rolling stock, aerodynamic, the instability of the dynamic properties of the pantograph and overhead catenary, etc. In view of the plurality of influencing the current collection of factors theoretically investigate the dynamical system "Pantograph - catenary" in full It is a complex task. A more rational to theoretical studies and sufficient for practical use is to consider deterministic processes. In the numerical simulation of the current collectors are the most common types of the following design schemes (models): lumped mass pantograph model; pantograph multibody schematics; pantograph multibody schematics in CAD-systems, which describe in detail the geometric dimensions and physical properties of each element of the pantograph. In the design of the pantographs is an integral part of the calculation of interaction of pantograph with contact suspension. Contact suspension counted in the calculations in the form of a concentrated mass interacting with the pantograph skid or a spatial system composed of resilient elements of finite length (catenary with distributed parameters). The second type of catenary model is used in the interaction with the first two types of models considered by the current collectors. Based on the features of each of the presented kinds of models, present the technique of the pantograph model selection, depending on the purpose of the simulation.

The results of edge stresses and stress measurements in the neck of the rail in a curve of radius 380 m, obtained in the tests on the effects on the way the locomotive CKD6e-2108, freight gondola 12-9941 and 12-9920, on railway line Almaty - Chu. The dependences of the stresses in the edges of the soles and neck rail on the speed of the test vehicles. The possibility of a transition from stress to lateral forces.