Fatigue Life Prediction For The Passenger Car Bogies Based On Result Of Test

Since the train's speed has been raised, the problem of the welded frame of bogie frequently turns up, which is aroused by various vertical, lateral and longitudinal alternating load during the movement. For the prediction of bogie's fatigue life, it faces not only the general difficulties which the non-welded structures have, but also the difficulties which are caused by welded techniques itself. Therefore, a study based on the test result of the passenger car bogie has the vital significance. This article mainly aims at following aspects:First, the static strength of the CW-2 passenger car bogies are analyzed by finite element method. According to the analysis results and welded forms, positions which are liable to appear fatigue failure are determined and regarded as the main predicted spots.Next, to obtain the dynamic stress spectrum, dynamic stress data are processed by the fatigue software of Eng company named nsoft. And these data are acquired by continuously movement of the welded frame of bogie on the Beijing-Urumchi round-trip line.Then, according to the S-N curve which is offered by the IIW and the Palmagren-Miner cumulative damage rule, the fatigue life of the welded frame are predicted based on the dynamic stress spectrum.Comparison between the predicted result and the test result is similar. So the predicted result based on the IIW standard is valuable. As a result of many influencing factors which welded structure have, the deviation is inevitable. But under the same stress spectrum, fatigue life improvement of welded joints detail can be obviously enhanced.