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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 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.

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.

In this article, the process of wear of the material of the ridge of the wheel brace during the movement of the locomotive in a curve of a given radius is considered. The methodology of the study considered in this article was that, based on the expression for the depth of penetration of the rail head into the material of the bandage ridge, the movement of the wheel along the inner rail in the curve was considered. It was taken into account that the contact point on the ridge of the bandage will move along the edge of the rail with slippage and that the contact area is a fairly narrow surface with a border close to an ellipse. Formulas for calculating the speed and the slip path of the contact point of the ridge of the locomotive wheel brace with the rail are obtained. As a result of the study, equations were derived to estimate such quantities as the volume, intensity and wear rate of the bandage (per revolution of the wheel). It is shown that the expressions obtained as a result of the work carried out can be used to calculate the intensity of wear of the brace ridge when the locomotive is moving in a curve of a given radius. The amount of the ridges material wear of the wheelset bandages can be determined on the basis of the equations obtained individually for a specific locomotive series and a given range of its operation.