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Results of mathematical modeling of determination of character and the law of change of forces and tension arising in the field of contact of interacting bodies on the example of dynamic contact at impact of an elastic sphere about motionless, absolutely rigid plate are presented in article, at its flat movement. The received results can be used at calculations of contact forces and material tension in a metalwork at shock influences.

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.

This article proposed a new method that determines the level of repair quality for any accounting period during the overhaul exploitation. A test example of depot repair quality of coaches is given.

The article presents the results of the development and implementation of a method for controlling the technological processes of repairing locomotives based on network planning. The methodology allows you to track online bottlenecks during current repairs and reduce the duration of the critical path by varying the time indicators of events and works, using the aggregate-nodal repair method, redistributing resources between critical and non-critical works. The developed methodology is based on the adjustment of basic repair networks, taking into account the workload of process equipment and repair personnel, the availability of spare parts and materials, the need for unscheduled work during the planned installation of a particular locomotive for repair. This approach was implemented within the framework of the automated control system (ACS) «Network Schedule» and provides control and adjustment of the implementation of technological operations according to the indicators of technological preparation of repairs. An algorithm has been developed for determining a generalized performance indicator when assessing the quality of functioning of an automated maintenance and repair control system for a locomotive in service locomotive depots.