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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 technical condition of the cylinder-piston group has significant effect on the reliable operation of the diesel locomotive engines. The most susceptible to the premature failure is the head of cylinders. It is caused by the heat release rate of the combustion chamber detail. The increase of the diesel locomotive engines cylinder heads durability in operation causes the relevance of the researches. In the article the set of the factors influencing on the diesel locomotive engine cylinder heads durability is defined, their main groups and subgroups are found. In the offered classification the subjective factors which directly depend on the human activity are dominated. It is possible to reduce the influence of the subjective factors by means of the human activity wrong solutions reduction while operating and repairing locomotives. The measures that improve diesel locomotive engine operation and positively affect the reliability of the cylinder heads are considered. Simple in implementation methods to extend the service life of the cylinder-piston group are offered. They are decreasing temperatures gradient during the post-stopping period of the power point and upgrading cooling system.

The method of determining the durability indicators of wheel pairs of locomotives is considered on the example of diesel locomotives of the 2TE25KM series operated on the Volga railway. For this purpose, the 90% resource of the wheel pairs of the studied series of locomotives was determined, and it was compared with the accepted standard indicator. In addition, a controlled parameter of the wheelset is selected, limiting the reliability of this node. To conduct the study, methods of mathematical statistics and probability theory were used, in particular, the Laplace distribution function, the Student's criterion, as well as the results of calculations of the dependencies of the mean value and the standard deviation of the controlled parameters, the initial values of developments and operating time corresponding to the probability of failure 0.5. In this study, a mathematical model for assessing the durability of wheelsets from the point of view of reliability theory was developed. The evaluation of the durability indicators of the wheelset elements was carried out on the basis of the type of random variable distribution law with its parameters obtained on a computer and adopted according to the Pearson criterion. As a result of the calculations, 90% of the life of the wheelset was obtained according to two controlled parameters, which amounted to 476.6 thousand km for the thickness of the bandage, and 282.6 thousand km for the thickness of the ridge. The results obtained were compared with the values adopted in the Technical Specifications for this series of locomotives (800 thousand km). km), as well as with statistical data on the values of controlled parameters obtained during processing and analysis - 240 thousand km. Due to the fact that in operation the average life of the wheelset is determined by a larger number of controlled parameters, taking into account unscheduled repairs, and in this study - only on the basis of the thickness of the bandage and the ridge, it is not possible to talk about full compliance with the calculated and actual data. According to the results of calculations, the limiting reliability of the wheelset is such a controlled parameter as the thickness of the ridge. For a more accurate assessment of the durability of wheelsets, it should also be taken into account that the intensity of wear of rolling stock equipment is affected by specific operating conditions, in this regard, inter-repair runs should be adjusted taking into account the influence of external factors during operation. In order to fully assess the durability of wheelsets in the future, it is necessary to take into account additional factors, in addition to those that affect the parametric change of random variables, as well as the fact that takes into account the monitoring and analysis of all controlled parameters of this node during the operation of locomotives.

In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.

At this time the traction electric motor (TEM) is one of the most important elements of the design of rolling stock, since the safety and stability of the transportation process on the railway network of JSC "Russian Railways" depends on its uninterrupted operation. This article is given a detailed analysis of the TEM failures of diesel locomotives of the 2,3TE10 v / series and the assigned fleet of the Novaya Chara locomotive depot of the East Siberian Traction Directorate. The section of circulation of diesel locomotives from Taksimo station to Hani station is one of the most difficult not only in the borders The East Siberian Railway, but also the entire railway network of the country. The analysis of the statistics of the reasons for the failures of the TEM of locomotives of the Novaya Chara locomotive depot for 2006 - 2012 showed that there is a rather extreme operation mode and that most of the failures are due to the breakdown of the insulation of the anchor winding of the TEM. During a research trip to the diesel locomotive maintenance site, a team of IRGUPSA scientists conducted full-scale measurements speed of movement, driving mode of the train, heating temperature of the TEM, taken into account the climate factors - ambient temperature, relative humidity, pressure and others. After studying the available information, it was proposed to additionally coat the insulation with FL-98 varnish in order to maintain and restore its properties in the conditions of the Winter locomotive depot during TR-3. IRGUPS has been working for a long time to study the process of drying insulation using infrared radiation (IR). The effectiveness of this method has been proven by numerous experimental studies. Several PhD theses have already been defended in various dissertation councils on this topic. This article presents also the statistics of failures of operated TEM already with additional varnish-impregnated insulation of open frontal parts after the implementation of measures based on the results of the work of the IRGUPS group of scientists. It is established that the method of applying the compound to the insulation of the frontal part of the windings of electric machines and encapsulating it with the help of IR radiation energy is effective in combating TEM failures due to insulation breakdown.