Design And Research Of Comprehensive Test Rig For Axle Box Bearings

With the continuous localization of high-speed railway vehicles,China has gradually mastered a series of core technologies.However,as one of the key components of bogie,the domestic research of axle box bearing is far from enough and has not yet been localized,which seriously affects the international process of Chinese high-speed railway vehicles.In the research filed of bearing,a large amount of test data resources are needed as technical support.Mature bearing manufacturers such as FAG and SKF have established excellent bearing test platforms,which can conduct various tests in accordance with bearing test standards.However,the domestic axle box bearing test is still in its infancy.Therefore,it is necessary to develop a comprehensive test rig of axle box bearing in China to meet the needs of the research and development of axle box bearing of high-speed train.The dissertation through the transformation of the existing small roller high-frequency excitation test rig in Southwest Jiaotong University,the overall design plan of the comprehensive test rig for axle box bearing of EMU is proposed,which can complete various bearing performance tests,fault tests and diagnosis.The prominent feature of the test rig is that the whole bogie(including primary suspension,secondary suspension,traction device,etc.)is used as the test object,making the state of the bearing closer to the running condition,and more accurately simulating the actual service environment of the bearing.Taking the axle box bearing test rig as the research object,this dissertation focuses on the bearing performance test design and fault diagnosis algorithm.The main contents can be concluded as follows:(1)The current situation of domestic and foreign axle box bearing test rig was summarized,the performance and characteristics of existing test rig was analyzed,the overall goal of the comprehensive test rig for axlebox bearings of EMU was determined.(2)Through analyzing the characteristics of axle box bearing and combining the bearing test standards,the performance requirements of the test rig in the test process,the bearing acceptance standards and bearing fault diagnosis method were clarified,and axlebox bearing test design plans were proposed.(3)According to the overall goal of axle box bearing test rig and the requirements of bearing test standards,the scheme of each component of the test rig and its function index are proposed.(4)The bearing fault diagnosis algorithm of the test rig was studied,and a morphological filtering algorithm based on cuckoo optimization was proposed.The effectiveness of the algorithm was verified by using the bearing outer ring fault simulation signal and the bearing inner and outer ring fault signal of Case Western Reserve University.(5)The morphological filtering algorithm based on cuckoo optimization was applied to the bearing test rig to realize fault diagnosis.The result showed that the algorithm can effectively remove the noise interference in the test process and effectively diagnose the bearing fault.