High Speed Rail IDEA Project 56 [Completed (IDEA)]
Signal Transmissibility of Railcar Bearing Vibrations
Project Data
Funds:
$58,329
Staff Responsibility:
Chuck Taylor
Effective Date:
4/27/2007
Fiscal Year:
2007
This is a project to measure the transmissibility of vibration signals from defective wheel bearings through the rolling wheel/rail contact patch to fixed accelerometers mounted on the rail. If adequate signal strengths and signal-to-noise ratios from defective bearing vibrations can be transmitted through this rolling contact patch, this would indicate the feasibility of a track-side system using arrays of accelerometers attached to the rail to detect bearing defects. Such a system would capture and analyze the distinguishable vibration signatures produced by various kinds of bearing defects. A wheel bearing with known defects will be installed in a test railcar. The bearing housing for the defective bearing and the housing for a bearing in good condition will be equipped with accelerometers. Three to four accelerometers will be installed on the rail of a test track. The test railcar will be moved along the test track at various speeds. Various types of rail contamination will be applied to the rail and the axle weights of the test car will be varied by adding ballast. Data from the rail-mounted accelerometers will be compared with that from the accelerometers on the bearing housings. The accelerometer data, together with the acoustic signatures previously obtained for the bearings will be analyzed to assess whether signal strength and signal-to-noise ratios are adequate for the development of a track-side acoustic bearing diagnostic system based on this concept. A wheel set containing a defective bearing and the associated acoustic bearing signature data collected from a wayside acoustic detection system (TADS) has been provided by Norfolk Southern.
