A set of circumferentially oriented thermal fatigue cracks (TFCs) were implanted into three cast austenitic stainless steel (CASS) pressurizer (PZR) surge-line specimen welds (pipe-to-elbow configuration) that were salvaged from a U.S. commercial nuclear power plant that had not been operated. Thus, these welds were fabricated using vintage CASS materials that were formed in the 1970s. Additionally, in-situ grown TFCs were placed in the adjacent CASS base material of one of these specimens. Ultrasonic phased-array responses from both types of flaws (implanted and in-situ grown) were analyzed for detection and characterization based on sizing and signal-to-noise determination. Multiple probes were employed covering the 0.8 to 2.0 MHz frequency range. To further validate the Pacific Northwest National Laboratory (PNNL) findings, an independent in-service inspection (ISI) supplier evaluated the flaws with their American Society of Mechanical Engineers (ASME) Code, Section XI, Appendix VIII-qualified procedure. The results obtained by PNNL personnel compared favorably to the ISI supplier results. All examined flaws were detected and sized within the ASME Code-allowable limits.
Revised: April 5, 2012 |
Published: July 31, 2011
Citation
Crawford S.L., A.D. Cinson, T.L. Moran, M.S. Prowant, A.A. Diaz, and M.T. Anderson. 2011.Ultrasonic Phased Array Evaluations Of Implanted And In-Situ Grown Flaws In Cast Austenitic Stainless Steel Pressurizer Surge Line Piping. In Proceedings of the ASME 2011 Pressure Vessels & Piping Division, July 17-21, 2011, Baltimore, Maryland, Paper No. PVP2011-57909. New York, New York:American Society of Mechanical Engineers.PNNL-SA-78594.