Abstract
High-pressure and high-temperature piping in fossil power plants suffer from unexpected and rarely predictable failures. To prevent failures and ensure operational safety, a Quantitative Acoustic Emission (QAE) non-destructive inspection (NDI) method was developed for revealing, identifying, and assessing flaws in equipment operating under strong background noise. This method enables overall piping inspection during normal operation, locating suspected zones with developing low J-integral flaws, identifying flaw types and evaluating danger levels based on J-integral values, and detecting defective components prior to shutdown. Combining continuous and burst acoustic emission as an information tool, the QAE NDI revealed, identified, and assessed significant flaws like creep, micro-cracks, pore/inclusion systems, plastic deformation, and micro-cracking in over 50 operating high-energy piping systems. Findings were independently verified by various NDI techniques, including time of flight diffraction, focused array transducers, magnetic particles, ultrasonic testing, X-ray, replication, and metallurgical investigations.
