The contact characteristics between the worn wheels of Shinkansen electric cars and rail. (Analysis of the effective conicity in geometrical contact).

The contact characteristics between the worn wheels of Shinkansen electric cars and rail are investigated geometrically. This wheel has the standard profile of Shinkansen with initially a 1/40 conical tread. The analysis method based on 2-dimensional contact is applied to asymmetric wheels of one axle, and the effective conicity γe is examined as the most important parameter toward the lateral vibration of the railway vehicle. In the analysis as to wheels of Type 925 electric cars, r-remains near the design value of 0.025 (= l/40) within about ad:5 mm lateral excursion of wheelset, even after a running distance of 268 000 km. When the wheelset with worn tread travels in a large amplitude, r- may increase up to 0.120.13. These features in the effective conicity of worn wheels prove the trend of lateral car vibration experienced in the long-term running tests.