Methodology for estimating the resource of the friction vibration damper of a freight car trolley

The concept of digitalization of railway transport and the introduction of digital technologies provides for the creation of a “Digital Railway” based on a “Digital Twin”, including a “Digital Twin” of a car, which implements a number of information and organizational measures aimed at assessing the current technical condition of a real car during its operation; reducing the cost of the life cycle of the car; increasing the reliability of assemblies and parts (increasing the overhaul life); reduced maintenance costs; creation of a service maintenance system for freight cars throughout the life cycle. However, the wear of vibration damper parts is the most important parameter that determines the turnaround time, the volume of repairs and the dynamic qualities of the car, which requires more detailed and reliable scientific substantiation. The assessment of the wear of vibration damper parts (friction bar, friction wedge, bolster) is carried out in two ways - by direct examination of them in operation (in this case, wear is estimated by changing the linear dimensions, i.e., in mm over the service life) and according to the results of bench tests of models of vibration damper or testing samples on friction machines (in this case, wear is estimated by the mass of the worn-out material). The proposed method for predicting the wear of parts of frictional vibration dampers implements the Archard friction model, takes into account the variability of loads acting on the working surfaces, for which a method for determining the friction path under various driving conditions has been developed. The developed methodology makes it possible to evaluate their service interval at the design stage of the car’s running gears.