Research On Load Distribution Of Axle Box Bearing Of High Speed Train

As the key component of the high-speed EMU transmission system,the axle box bearing is very important for the safe and stable operation of the train.At the same time,the domestic complex and harsh operating environment puts forward more stringent requirements for its fatigue life and reliability evaluation.The dynamic load distribution inside the bearing is one of the most important operating parameters of the bearing,and it is also the key mechanical parameter from the service condition to the fatigue life evaluation of the bearing.Therefore,it is of great significance to obtain the internal dynamic load distribution of axle box bearing for accurate evaluation of fatigue reliability of axle box bearingIn this thesis,the axle box bearing of a high-speed train is taken as the research object,and an experimental mechanics method based on strain detection is adopted.The strain response of the outer ring of the bearing is measured to obtain the internal dynamic load distribution of the bearing by introducing notches along the axial direction and circumferential direction into the inner wall of the bearing housing.The static finite element model of single row axle box bearing is established.The influence of notch size and position on the load distribution inside bearing and strain response of bearing outer ring are studied parametrically.The results show that the introduction of notch into the inner wall of bearing housing will not affect the load distribution inside the bearing.Select the axial notch angle as 6° with a depth of 2mm,the circumferential notch width is 15 mm,and the notch center is 34 mm away from the end of the bearing,the obvious strain response will be obtained.It is also beneficial to the arrangement of strain gauge.According to the principle of bearing load test,an experimental device suitable for load distribution test of axle box bearing of high-speed train is designed and built.The dynamic strain distribution test and calibration test of axle box bearing with different notches were completed by using the experimental device.According to the dynamic strain signal under different working conditions and the load strain transfer matrix obtained by calibration test,the dynamic contact load distribution of axle box bearing under different radial load and speed is obtained under different notches.The dynamic load distribution under different notches is compared and analyzed.Without considering the error of test device,loading system and bearing installation,the axial notch and circumferential notch can effectively test and evaluate the load distribution of axle box bearing.