Strength Analysis Of CRH380B EMU Trailer Bogie Frame

Bogies are an important part of rail vehicles,and the frame is one of the key components of bogies.All components of the bogie are assembled together to form the whole bogie through the installation of the frame.During the train operation,the bogie not only supports the positioning of the car body and the wheel-axle box,but also bears and transmits various internal and external alternating loads and excitation functions from the car body and the line.In recent years,with the rapid increase in the running speed of railway vehicles in our country,the structural strength of the frame is insufficient,and fatigue damage has increased significantly,posing a serious threat to the traffic safety.Therefore,whether its original design can meet the structural strength requirements of current high-speed operation has become the focus of many researchers.In this paper,the CRH380 B trailer bogie frame is taken as the research object.According to the relevant dimension data of design and manufacture,the 3D geometric model of the frame is established by Solidworks 3D modeling software.After simplifying the model,Hypermesh is used to discretize its overall structure,and the finite element analysis model of frame strength is established after adding constraints.According to UIC515-4 standard of the International Union of Railways,the static strength of the frame under 15 combined working conditions is calculated by finite element method.The maximum stress of each working condition does not exceed the maximum allowable stress.The results show that the static strength of the frame meets the requirements.The Goodman-smith fatigue limit diagram was used to evaluate the fatigue strength of the frame.The corresponding points of the selected evaluation position coordinates all fall within the Tu Tu line of the fatigue limit of the frame,and the fatigue strength of the frame also meets the requirements.Based on the results of static strength analysis,the fatigue life of the frame is estimated by Fe-Safe software.The minimum life of the frame at the circular hole of the lower cover plate of the side beam is13.96 million times greater than 10 million times specified in UIC515-4 standard,and its life meets the design requirements.Finally,ANSYS constrained modal analysis is carried out on the frame,and the results show that its lowest natural frequency is 28.698 Hz,which is much higher than the natural frequency of 10 Hz from the components such as lines and car bodies.No resonance phenomenon occurs,and the dynamic stiffness design of the frame is reasonable.