Signal Transmissibility of Railcar Bearing Vibrations

This report summarizes research into the transmissibility of signals from a defective rail car wheel bearing from the source of the defect to rail-mounted accelerometers. This Innovations Deserving Exploratory Analysis (IDEA) project evolved from an initial proposal to develop a wayside defective bearing detection system using rail-mounted accelerometers. It was not clear if the defective bearing signals can be transmitted to the rail through the rolling wheel-rail contact patch. The rolling contact patch could, especially, pose a challenge for the technology. Possible contamination at the wheel/rail contact may further complicate the situation. The objective of the project was to investigate the transmissibility of the wheel bearing vibration signals through the complicated path from the defective bearing to the rail-mounted accelerometers via the rolling contact patch. Following successful lab tests, field tests were conducted to collect sufficient data to enable detailed analyses to determine how well the bearing vibration signals could be transmitted from the bearings to the rail. The tests involved the use of a known defective bearing fitted on a test car hauled over a rail section equipped with accelerometers. The data collected from the field tests were analyzed using a high-frequency vibration envelope detection technique. Data analysis results for the onboard data indicated a bearing cup defect. The results of the wayside data analysis indicated the bearing defect signature was evident even under worst-case test conditions. Further development of this concept will require additional tests at higher speeds with better track conditions, using a full array of track sensors to fully determine its feasibility.

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  • Supplemental Notes:
    • This HSR-IDEA project was conducted by ENSCO, Incorporated, Springfield, Virginia. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
  • Authors:
    • Zhang, Yu-Jiang
    • Hernandez, Walter
  • Publication Date: 2008-2


  • English

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Filing Info

  • Accession Number: 01145899
  • Record Type: Publication
  • Report/Paper Numbers: HSR-IDEA Project 56
  • Files: TRIS, TRB
  • Created Date: Dec 4 2009 9:52AM