Description

This presentation discusses the early development and in-service assessment of locomotive undercarriage thermal inspection systems (LUTIS), also known as “in-track thermal detectors.” MxV Rail installed thermocouples (TC) and data loggers on three different styles of locomotives to record the real-time temperatures of the high-load mechanical components as the locomotives traversed the network. The TC locations were selected to be visible to the in-track LUTIS. The continuous data obtained from the onboard unit was useful for determining warmup profiles and average operating range temperatures for the various components. When the locomotives passed the test site, direct point-by-point temperature comparisons were made between the TC data and the in-track LUTIS readouts. The revenue service trials of the in-track LUTIS demonstrated a good correlation between the scanned and onboard temperature measurements. Overall, differences averaged approximately 1°C between the two LUTIS units themselves, and approximately 3.6°C between the thermocouples and either of the in-track units. These differences were minor when considering the inherent differences of each measurement system (e.g., thermal scan technology, resolution, precise location of the thermocouples versus scan target) and the range of operating temperatures. The differences appear insignificant when compared with temperatures associated with an impending component failure. Further work from the industry has been focused on trending and identification algorithms to identify abnormal temperature readings and trends. Early deployment in revenue service of more than a dozen units resulted in at least 120 indications in the first year.