The dissertation is devoted to the problem of ensuring the reliability of freight cars in order to increase the lifespan of the life cycle and improve the state of safety of the movement. In the theoretical aspect, the scientific basis for the formation of freight cars reliability indicators has been developed at the stages of the life cycle, which in practical terms can significantly reduce operating costs with the possibility of lengthening the useful life, taking into account the correction of the maintenance and repair system.
In the first section, the analysis of the technical condition of the park and the failures of freight cars of Ukraine was carried out, the methods of increasing the reliability of carriages of cars at the stages of the life cycle were considered, the calculations concerning the theoretical positions of the study of reliability indicators of freight cars were made. At the same time, the analysis of the traffic safety situation in the railway carriage of railways of Ukraine and the failures of freight cars showed that as a result of detachment of cars in the current repair due to malfunction of the units, the wagon economy suffered losses at the level of 4,503 UAH / tone-km, falling on one car. Therefore, for new freight cars that are only being manufactured, it is necessary to develop measures to ensure reliability at all stages of their life cycle.
In the second section theoretical studies of reliability of freight cars at the stages of the life cycle have been conducted. In this case, improvement of the algorithm for the study of the reliability of freight cars at the stages of the life cycle, an estimation of the indicators of wear of the elements of the carriage of cars with the use of the classical probability theory was carried out, the pro-harrowing of reliability indicators of freight cars, taking into account the term of their operation. On the basis of the existing reliability theory, a methodology for determining the reliability of freight cars, which includes methods for determining indicators at all stages of the car life cycle, is based on the analysis and synthesis of theoretical and experimental data on the technical condition and basic parameters of the reliability of the car as a mechanical multi-element system.
In the third section, mathematical modeling of the process of formation of reliability indicators of freight cars at the stages of the life cycle of design was performed. In this case, the formation of reliability indicators of cars at the design stage was completed, reliability indicators of wagons were determined at the manufacturing stage and an assessment of reliability indicators of freight cars at the stage of operation was carried out. To determine the period of safe operation of wagons and forecasting of relevant economic indicators that characterize maintenance and repair costs, the concept is formulated and an expression for the complex index of operational reliability of van-cars at the appropriate stage of the life cycle is obtained. To determine the suitability of freight cars at the stage of the life cycle - the technological process of manufacturing components and components, the method of determining the off-languages and assessing the reliability of the car, which envisages the possibility of forecasting the DM in operation, taking into account the peculiarities of the technological process of preparing the components of the car, is improved with the prevention of defects. As a result of studies on the reliability of freight cars in the life cycle - operation, it is proposed to determine the timing of regulatory maintenance, current, depot and capital repairs of freight cars, with the definition of parameters of operational reliability of freight cars: readiness coefficient, probability of failure-free operation and performance tasks.
In the fourth section, the formation of a system for investigating the reliability of freight cars of various structures has been completed. In the first subdivision, individual models of forecasting the reliability of freight wagons during the life cycle are developed, taking into account the probabilistic nature of the off-languages. In the second subdivision the system of research of indicators of reliability of freight cars with the account of the current technical condition at all stages of a life cycle is developed.
The fifth section presents the results of theoretical and experimental studies of freight cars reliability indices. As a result of the feasibility study of the proposed technical and technological solutions for ensuring reliability, a reduction in the cost of the lifecycle of a gondola can be achieved by 14.2 thousand UAH. Since the work park of gondola cars on the Ukrainian railways is 83 302 units, the overall economic effect of the proposed solutions is UAH 1,183 million.
