Qualification requirements of guided ultrasonic waves for inspection of piping in light water reactors

It is anticipated that guided ultrasonic wave (GUW) techniques will eventually see widespread application in the nuclear power industry as there are several near-term and future needs that could benefit from the availability of GUW technologies. Already, GUW techniques are receiving consideration for inspecting buried piping at nuclear power plants and future applications may include several Class 1 and 2 components. To accept the results of a nondestructive examination of safety critical components, the U.S. Nuclear Regulatory Commission requires that the examinations be performed using qualified equipment, personnel, and procedures. As the use of GUW techniques becomes more frequent, qualification may be required. Performance demonstration has been the approach to qualifying conventional NDE methods in the nuclear power industry. This paper highlights potential issues and research needs associated with facilitating GUW qualification for the nuclear power industry. Parametric studies of essential inspection parameters are necessary to understand their influence on inspection performance. The large volume sampling capability introduces several challenges for qualifying GUW techniques including the quantification of performance, potential interference caused by the presence of multiple flaws in the inspection region, and the practicality of manufacturing several large qualification specimens. Computer simulation may have a significant role in reducing the experimental burden associated with qualifying GUW techniques for nuclear power plant