Railroad wheels

Straman et al [2003] have developed quantitative criteria for removing railroad wheels from service, based on real-time structural health monitoring trends using data collected from trains while in-service. The data are collected using Wheel Impact Load Detectors (WILDs). These impact load trends are able to distinguish wheels with a high probability of failure from high impact wheels with a low probability of failure. Traditionally, wheels are removed based on drive-by visual inspection and the high impact condemning limit. Unfortunately many damaged wheels are not found with the drive-by inspection method, while many useable wheels are removed when they could remain in service. The structural health monitoring trends developed in the paper provide a quantitative decision method based on the wheel impact data which indicate the actual condition of the wheels.