Analysis of factors affecting the coefficient of friction of the brake pad of rolling stock
Keywords:
rolling stock of railways, the coefficient of friction of the pad on the wheel, the coefficient of adhesion of the wheel with the rail, braking efficiencyAbstract
Today one of the limiting factors in increasing the local and maximum train speeds, which directly affect the profit of the railway company, is braking efficiency. The pad in the brake system is the first direct element that forms friction on the rolling surface of the rotating wheel, and the brake lever gear and brake cylinders serve solely to ensure that the brake pad is pressed with the required force. If the brake pads are absent, friction is not feasible and all other devices are designed directly to control the friction force in relation to its magnitude and duration. The coefficient of friction plays an important role in the formation of the braking force, which also determines its magnitude. In this article, we examined various methods for determining the coefficient of friction, as a result of which the dependences of the influence of factors such as the force of pressing the pad on the wheel, the chemical composition of the pad, the shape of the pad, the degree of moisture of the pad, the wear of the pad, the initial duration of friction were revealed; the temperature of the pad and the rolling surface of the wheel by the value of the coefficient of friction. These issues were dealt with by both domestic scientists, such as M. Metskov, V.F. Egorchenko, and foreign scientists, the most prominent representative is Galton. Despite the significant contribution made by the scientists represented, it is necessary to continue research in this area in order to increase the speed of movement of rolling stock and related other operational indicators, which will directly affect the increase in profits of JSC "Russian Railways" and reduce various economic losses.
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