Analysis of influencing factors of braking temperature on wheel of freight wagon in full wear cycle under long ramps

This paper aimed to investigate the effects of the line slope, the vehicle braking time, wheel-brake shoe contact area, and wheel-brake shoe contact force on the temperature of the wheel tread and brake shoe when a truck brakes on a long ramp. A single long downhill route was used as the research background in this paper. A full-scale three-dimensional finite element model of the wheel and brake shoe was created using the ANSYS finite element software program. The wear of the wheel and brake shoe was considered by changing the wheel diameter and brake shoe thickness. The effects of the above factors on the wheel tread temperature to achieve the temperature of martensite phase transformation were investigated. The change in the temperature fields of the wheel tread and the brake shoe with the influencing factors during the whole wear cycle of the wheel and the brake shoe was studied. The results show that with the decrease in wheel diameter, the temperature of the wheel tread and brake shoe increases nonlinearly. When the brake shoe thickness decreases uniformly, the temperature of the wheel first decreases nonlinearly and then stabilizes, and the temperature of the brake shoe first decreases nonlinearly and then increases. The relationship between the temperature and the wheel diameter, the brake shoe thickness, the vehicle braking time, and the wheel-brake shoe contact area is nonlinear. There is a linear relationship between the temperature and the slope and the wheel-brake shoe contact force. Assuming that the martensite phase transformation temperature is 700 ℃, the wheel tread reaches the martensite phase transformation temperature by the combination of wheel-brake shoe contact force, wheel-brake shoe contact area, vehicle braking time and other influencing factors. This study can serve as a theoretical reference for the analysis of wheel thermal damage, the design of railway lines with long ramps and the operation mode of trains. © 2024, J. Health. Saf. Work. All rights reserved.