Stress based non-destructive evaluation using thermographic approaches: From laboratory trials to on-site assessment

Vibration based loading has been successfully used to facilitate out of laboratory inspections using thermoelastic stress analysis enabling stress based non-destructive assessment of structures. An initial plate study verified the technique. A laboratory demonstrator of the on-site implementation was created to facilitate the development and assessment of a suitable loading device. The developed system was then taken on-site at a coal fired power station during a scheduled outage period. Vibration loaded thermoelastic stress analysis was successfully applied to welds in high pressure steam drain lines in-situ.