Study On Load Test Method Of Bearing Based On Structural Modification Of Axle Box

As one of the key technologies in railway trains,the axle box device is responsible for the major mission of transforming rolling motion of wheel set into translational motion of car body.Without the axle box device,the vehicle cannot realize the transportation function.At present,the demand for trains of high-speed and heavy-duty is becoming more and more intense.In order to meet this requirement,the service condition of axle box bearing has deteriorated day by day,especially the safety performance of axle box bearing which is a rolling part in axle box device is extremely important.Research on the load of axle box bearing is of great significance to guarantee the safety of bearing during train operation.It is also a powerful theoretical basis for getting rid of the bottleneck of importing high-speed train bearing and realize the localization of bearing.This paper takes the bearing used in the axle box of the CRH3 EMU as the object,and carries out the load test research on it.The main work is as follows:(1)Analyzed the load type of the axle box bearing during the operation of the vehicle,and obtained the main load type of the axle box bearing.Through the establishment of the vehicle and track dynamics model to simulate the operation of the vehicle line,the spring load and the arm load that play a decisive role on the axle box bearing during the operation are extracted.The results show that the load extracted by simulation is consistent with the load data obtained from measured lines.The spring load is much larger than the arm load,and it plays a major role in the fatigue and life of the axle box bearing.(2)The internal load distribution of the axle box bearing under the spring load(radial load)is calculated by the numerical method and the finite element method,and the results show that the results of the two methods are consistent.The visual load distribution characteristics of the bearing and the stress distribution law of the outer ring of the bearing are obtained by finite element calculation.Based on this,the load sensitive point of the bearing is found and used as the load test point of the bearing.(3)According to the calculation results of bearing load distribution,the bearing load test method of grooving axle box is put forward.Through comparative simulation,the concrete scheme of grooving the axle box is determined.The feasibility of the bearing load test method is verified by comparing the stress response of the models before and after modification of the axle box.The strength of the modified axle box and the stiffness of the bearing are evaluated,and the results show that both of them meet the requirements.(4)The load test method proposed in this article is studied based on statics and display dynamics.The modified axle box bearing model is simulated and analyzed by finite element software,and the stress response of axle box bearing under different working conditions is obtained.Under the bearing load test method proposed in this paper,the relationship between the stress at the load test point and the external load is analyzed,and then the stress-load transfer coefficient is obtained.This article has 87 pictures,16 tables,and 66 references.