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Purpose: To develop an improved model of inter-car coupling equipped with spring-friction absorbing devices of the PMK-110 type. This model should take into account both the features of the power characteristics of absorbing devices of this type and the deformation of the carriage bodies, as well as the energy dissipation of longitudinal forces arising in the train due to the viscous resistance to deformation of the car structure. Methods: Methods of analysis, mathematical and simulation modeling. Results: Based on two existing mathematical models of inter-car couplings with spring-friction absorbing devices, an improved model of inter-car coupling equipped with spring-friction absorbing devices of the PMK-110 type has been developed. It is shown that this model increases the reliability of calculating the values of the longitudinal forces arising in the absorbing devices of the intercar couplings of the train. Practical significance: The proposed model of inter-car coupling can be used in studies of longitudinal vibrations of a train, since it gives more reliable calculation results for all loading modes.

The study objective is to develop and analyze mathematical models of vibrations of a passenger car with elastomeric dampers. The problem to which the paper is devoted is to improve the dynamic characteristics of the undercarriage of passenger cars and increase passenger comfort. The research methods used in this study are typical for solving the problems of rolling stock dynamics. The car is approximated by a system of concentrated masses connected by elastic and dissipative bonds. The external impact is track irregularities of different types. Differential equations of motion are combined using D'Alembert's principle. The set of equations is integrated by numerical method. The novelty of the work is, firstly, in the use of an elastomeric vibration dampener on the bogie of a passenger car, secondly, in the analysis of the dynamic qualities of this car when moving over the irregularities of the main types, and thirdly, in the choice of rational parameters of elastomeric dampers. The results of the study are graphs, nomograms and tables of the dependencies of maximum force values on various parameters, as well as an assessment of the movement smoothness. The conclusions of the work contain an assessment of the dependence of dynamic parameters on speed, recommendations on the characteristics of elastomeric dampers, the validity of using elastomeric dampers.

The paper is devoted to modeling the stress-strain state of a car wheel in the case of its heat treatment. The calculation technique is based on the application of the finite element method for a specialized design diagram. The final elements have the form of rings of triangular cross-section. The initial equations are used on the basis of the theory of elasticity. The approximation of movements along the axis of rotation and along the radius is linear, in the circumferential direction it has the form of trigonometric series. Using the proposed technique, calculations of a wheel with two variants of rim hardening are implemented: as one annular strip on the rolling surface and with the use of two additional strips with an intermediate degree of hardening. The developed means of modeling can be used to develop methods and to select wheel hardening parameters.

The study objective is to develop methods for performance evaluation of center coupler draft gears in various operating conditions. The problem to which the paper is devoted is to reduce the dynamic loading of the rolling stock by means of using efficient draft gears. The research methods on which this study is based are widely used in the dynamics of railroad cars. Typical modes of shunting impact of cars are considered, which are characterized by the highest level of forces in automatic couplings. The design schemes of impacts are considered as a system of connected material points. On the basis of D'Alembert's principle, differential equations of motion are made, and they are integrated by the Euler method. The novelty of the work is in developing an approach to evaluate the performance of draft gears using the proposed integrated evaluation. The results of the study are the nomographs of the effort in the draft gear, depending on car weight and the speed of impact. The conclusions of the study contain the evaluation of the results of applying the proposed approach, as well as recommendations on possible use of the proposed approaches.