This article considers the coefficient of friction between the brake shoe and the wheel of the railway rolling stock. It conducts a review of the works on the study of the interaction of the brake shoe and wheel, considers a method for obtaining the calculated value of the friction coefficient used in the Russian Federation and in many countries, and indicates a drawback of this method that leads to errors in the calculations. The paper specially focuses on the study of heating of brake shoes during braking as a factor in changing the coefficient of friction between the wheel and the brake shoe. The FEM model of heating the brake shoes during braking is constructed taking into account changes in the mass and shape of the brake shoes during wear. Brake shoe wear is considered as a factor in changing the effectiveness of train brakes.

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Annotation One of the most loaded structures, and at the same time, the weakest elements of the power equipment of traction rolling stock, is isolation. The analysis of the operation of power equipment of electric locomotives from the negative impact of climatic factors on it has been made. It was revealed that to ensure reliable and safe operation, a system of maintenance and repair of rolling stock is necessary, taking into account the zonal conditions of operational features. The necessity of creating adaptive systems to maintain optimal values for temperature and humidity conditions for the insulation structures of electric locomotives is shown.

The article is devoted to the assessment of the comparative experimental studies’ results of various technologies for drying impregnated insulation of power electrical equipment in the process of manufacturing and repair: standard technology, which provides for convective drying using high-power electric ovens, and the proposed technology and methods for accelerated drying in hardware complexes using infrared (IR) radiation. In particular, the article presents the results of the polymer insulation surface microstructure analysis after drying by the indicated methods. The research was carried out in an industrial environment, using specialized certified equipment. In theoretical terms, the article presents the calculations on the rationale for the use of IR radiation during drying of a multilayer insulating structure of various compositions. The studies carried out confirm the hypothesis about the formation of microcavities on the surface and in the thickness of the polymer insulation when using convection during drying, which reduce the quality and reliability of the electrical equipment insulation as a whole. At the same time, the proposed technology and technique for accelerated drying of electrical equipment insulation using IR-radiation gives an opportunity to improve the quality of the resulting polymer insulation, increasing its reliability. In addition, this technology can significantly increase the productivity of insulation repair and reduce energy costs.