Temperature Field Analysis Of Brake Wheels On Heavy-duty Train Treads And Research On Brake Fault Diagnosis

With the rapid development of my country's heavy-duty railways,the performance of heavy-duty railway systems has been continuously improved.The brake system is the core component of the train,and its running state is related to the running safety of the train.Existing brake system fault diagnosis is mostly based on the online measurement method of the measured pressure and other data,and there is still no relevant research on the online diagnosis of the brake friction pair fault.This paper takes the wheels of heavy-duty trains as the research object,takes the wheel temperature field of different brake friction pairs with long downhill slopes and periodic braking mode as the research basis,and establishes the weight-based temperature based on the site conditions and existing standards.On-line early warning and diagnosis standards for friction pair faults in train braking systems.The specific work content and conclusions are as follows:(1)The ANSYS Workbench finite element software was used to establish a three-dimensional finite element model of the tread brake wheel of the heavy-duty train,and the boundary conditions of the three-dimensional temperature field of the wheel were determined.Based on the friction power method,the innovative reference analysis method was used to calculate the heat flux density of the wheels,and the reliability of the model in this paper was verified by the brake test of the 10,000-ton heavy-duty train.On this basis,the wheel temperature field of the 10,000-ton heavy-load train with periodic braking on the long downhill slope was studied in detail,which laid the foundation for the subsequent temperature field research.(2)The temperature field of wheels of 10,000-ton heavy-duty trains under different brake friction pairs is studied.The specific analysis of the brake shoes at both ends of the same brake beam is performed on one side,the brake shoes are laterally(inner and outer)unevenly worn to varying degrees,the brake shoes are laterally(inner and outer)unevenly worn-unilateral braking,and different wheel diameters are used to brake The influence of the lateral(inner and outer)tile wear and unilateral braking on the wheel temperature field has obtained the change law of the wheel temperature field.The results show that the temperature rise of the wheel as a whole,the lateral surface of the tread and the spokes is more obvious under the brake shoe unilateral braking conditions.The maximum temperature of the wheel as a whole,the tread lateral direction and the spokes under the brake shoe's lateral partial wear are proportional to the external partial wear and inversely proportional to the internal partial wear.Compared with the normal conditions,the maximum temperature of the tread lateral and the spokes under the brake shoe lateral eccentric wear-unilateral braking conditions are increased,and the increase is proportional to the external eccentric wear and inversely proportional to the internal eccentric wear.The failure of each brake friction pair under different wheel diameters has a similar effect on the wheel as a whole,the lateral direction of the tread and the temperature of the spokes.Comprehensive analysis shows that the temperature at different lateral distances from the outside of the wheel and the temperature at different distances of the non-rim side along the spoke at different distances of the friction conditions of different wheel diameters and friction pairs will have a certain increase or decrease and increase and decrease from normal conditions.The range is more obvious.(3)Research on fault diagnosis of friction pair of heavy-load train based on temperature.First,according to the fault frequency,the severity of the fault and the on-site recommendations,the severity level of the friction pair failure of the heavy-duty train braking system was determined;then the temperature standards for online warning and diagnosis of the friction pair failure of the brake system based on temperature were established based on the test conclusions and temperature laws Finally,the temperature standards are used to provide inspection suggestions for the bogies that may have friction pair failures,which provides new ideas for the online diagnosis of heavy-duty train braking systems.