Acoustic emission method to detect cracks and leaks of the nuclear steam supply system

The work on using Acoustic Emission (AE) method for continuous surveillance of reactor pressure boundaries of nuclear power plants to detect crack or leak of coolant and to evaluate the severity of the flaws is in progress, and has been studied in this report. Several tests and analyses have been accomplished, and the technique to identify the acoustic signal produced by flaw growth, to locate the acoustic source, to relate the signal level to the crack growth rate and leak rate, and to identify the type of flaws is proved to be feasible. There have been efforts to describe the flaw theoretically using fracture mechanics that are helpful in the flaw evaluation. Instrumentations systems to implement the AE technique are surveyed, and the result shows that the current AE detection systems in domestic nuclear power plants can be improved by adopting the up-to-date accomplishments in AE methods. 47 figs., 17 refs. (Author)