Heat calculation of pads during locomotive braking
Abstract
During braking, the process of friction between the brake shoe and the wheel occurs at the points of their actual contact. The total area of these contacts is negligible compared to the area covered by the brake pad. Since the release of heat occurs only at the points of actual contact, the densities of heat fluxes and temperature flashes in them can reach large values, causing the friction surface to glow and the transition of the metal at these points to the plastic state. In this paper, calculation methods of estimation of rolling stock brake system wear are reviewed, and temperature fields and also stresses in material of wheelpairs tires at operation are studied. Estimations of temperature fields in the tire material during braking of locomotives were studied in the course of the methodology. Assumptions were used in the considered problem, such as choosing a wheel set tire model under loads, sliding speed and friction force. Methods for controlling the braking power of the wheel NT in each cycle of braking time is shown to be absorbed by the part of the tire mass.