Two-axle bogie design for electrical multiple unit: Part 2: Bogie frame fatigue test

The present article describes the bogie fatigue strength test. The bogie fatigue strength test was conducted on an unpainted bogie frame to verify compliance with the FEM analysis of bogie design. According to the bogie static strength test, we can compare the measured stress from the bogie fatigue strength test with the calculated stress values of the FEM analysis. The bogie fatigue strength test was conducted on an unpainted bogie frame valid for DM1, T and M2 Cars. Nondestructive Testing (NDT) was carried out on this bogie frame. Imperfections found by nondestructive examination of the bogie frame before and after the fatigue test were evaluated. No crack induced by the test is permitted anywhere in the bogie frame (base material and welding included). The measured stresses given in the modified Goodman diagrams show that the fatigue stresses are within allowable limits.