Roller Bearing Failure Mechanisms Test and Wheel Anomaly Test Report

摘要

A series of roller bearing performance tests were performed by the Association of American Railroads (AAR) as part of a Federal Railroad Administration (FRA) Task Order entitled 'Freight Car Equipment Research.' The objectives of these tests were toinvestigate the performance of degraded roller bearings, and quantify the effects of four common wheel tread anomalies on the dynamic load environment of the roller bearing. Test results support the following conclusions: The grooved axle journal defects tested developed temperature gradients on the bearing cup which may be useful in identifying the defect type; A grooved axle condition developed on one of the test bearings and six other bearings showed evidenceof cone slippage on the axle journal; Wayside detector alignment and scan location are critical factors in successful detection of an overheated bearing; The peak loads produced by the wheel defects at the speed ranges tested were significantly lower at the bearing adapter than at the rail. The peak loads were also significantly higher then the static loads at the wheel.