EXPERIMENTAL STUDY ON THE FATIGUE STRENGTH OF THE BOGIE FOR KOREAN TILTING TRAIN

초록

This study has performed the experimental study to evaluate the fatigue strength of a bogie frame and tilting bolster that will be applied to Korean tilting train TTX. Before the experimental study, loading conditions based on the international standard (UIC615-4) were investigated. In order to derive the tilting load cases that have not established. The dynamic analysis for consideration of the carbody tilting effect was performed. For the fatigue strength evaluation, both static load test and fatigue load tests was performed. The twenty-three load scenarios including tilting loads were considered in the static load test. All the stress measured were under the welding allowable limit of Goodman diagram, so the bogie frame was proved to be safe against fatigue load up to its 25 years life. Additionally the fatigue load test was performed to consider all possible weak points and workmanship not identified by the static tests. Fatigue crack detection test using liquid penetration test (PT) was carried out at 6x106cycles and the liquid penetration test and magnetic particle test (MT) were conducted at 6x10^6cycles. No fatigue cracks were found after final 6x10^6cycles, therefore bogie frame was proved to be safe enough against more than 25 years fatigue load.