Analysis of three-people seat underframe in motor train unit based on FEA and experiment

To investigate the strength of structure of three-people seat underframe in motor train unit, two analytic methods which are FEA and experiment are used. Firstly, the seat underframe model is established which is based on the existing seat underframe. Secondly, the seat underframe is grid-meshed and restricted and the material parameters of it are also defined. Then, the FEA model of the seat underframe is established by using U-shaped load method and gasket-shaped method according to the enterprise regulation and experiment condition. Based on the analysis results of three-people seat underframe, in U-shaped method the flexivity of the test point (in the middle place of front longeron) is 1.039 mm, the maximum flexivity of the central turntable is 1.45 mm and the maximum stress of whole underframe is 137 MPa while in gasket-shaped method the flexivity of the test point is 0.9739 mm, the maximum flexivity of the central turntable is 2.7 mm and the maximum stress of whole underframe is 128 MPa. And the analysis result is verified by the experiment. According to the experiment requirements in enterprise, the experiment mainly inspects the flexivity of the middle place of front longeron and the experiment result is 1.06 mm. It can be known that the results of the simulation and the experiment are basically same.