Deterioration and Thermographic Analyses of Electrical Units in Diesel Locomotive

Abstract

The electrical units of diesel electric locomotives, which were used for over 30 years, were characterized for deterioration evaluation through insulation resistance measurement, degradation testing, and infrared thermography method. Especially, an infrared camera and thermocouples were employed for the evaluation. The thermocouples were attached on high-voltage cables connected to traction motors, for in-situ measurement of abnormal heating during test running. After test running, the thermographic images were obtained for the inspection of high-voltage cables using the infrared camera. The thermographic results were quantitatively analyzed, and compared with temperature changes during running. In this investigation, various analysis techniques for the safety characterization of diesel electric locomotives have been introduced, and the analysis results have been used to provide the deterioration or wear information in current locomotive systems.

Non-Destructive Characterization of Railway Materials and Components with Infrared Thermography Technique

“…If a railway operator needs to extend the life of the vehicle, it should be diagnosed with items such as the current condition assessment, safety evaluation, and residual life assessment of the vehicle. According to the diagnosis results, it is legally possible to extend the service life up to 5 years [5].…”

“…In this study, as part of the precision inspection of railway vehicles, the insulation resistance measurement, degradation test, and deterioration evaluation of the electric equipment in diesel electric locomotives used for more than 30 years were carried out using infrared thermography [5].…”

“…In order to operate a safe railway vehicle, it is directly related to the maintenance activities of the railway system, and, accordingly, efficient maintenance is required. In general, many efforts have been made in the railway vehicle industry to manage various defects which are formed during operation or generated during manufacturing [1][2][3][4][5].…”

“…Various types of non-destructive evaluation (NDE) technologies are used during the regular maintenance of railway vehicles including ultrasonic testing (UT), magnetic particle testing (MT), radiography (RT), and infrared (IR) thermography [1][2][3][4][5]. Among the possible NDE technologies, infrared (IR) thermography is a relatively new technology in the field of railway maintenance and is an advanced non-destructive evaluation technique based on infrared detection [5][6][7][8][9][10]. In particular, infrared thermography technology is an advantage, providing fast full field and real-time inspection as well as contactless mode.…”

“…Thus, the main objectives of this study on the NDE of railway materials and components using IR thermography technology were to (1) introduce the current state of railway field applications using infrared thermography technology, (2) explore the failure mode and fracture mechanism of railway steel materials with the help of IR thermography technology, (3) monitor the temperature changes during brake operation of railway brake discs, (4) perform thermal imaging inspections on electrical devices of diesel electric locomotives, (5) conduct thermographic detection on railway bogies using infrared thermography technology, and (6) develop non-destructive evaluation tools for detecting defects in railway vehicle components.…”