A study was conducted to assess the ability of advanced ultrasonic techniques to detect and accurately length-size flaws from the far-side of wrought austenitic piping welds. Far-side inspections of nuclear system piping welds are currently performed on a “best effort” basis and do not conform to ASME Code Section XI Appendix VIII performance demonstration requirements. For this study, austenitic stainless steel specimens with flaws located on the far-side of full penetration structural welds were used. The welds were fabricated with varied welding parameters to simulate as-built conditions in the components, and were examined with phased array technology at 2.0 MHz, and low-frequency/Synthetic Aperture Focusing Technique (SAFT) methods in the 250-400 kHz regime. These results were compared to conventional ultrasonic techniques as a baseline. The examinations showed that both phased-array and low-frequency/SAFT were able to reliably detect and length-size, but not depth size, notches and implanted fatigue cracks through the welds.
Revised: July 30, 2009 |
Published: January 1, 2007
Citation
Anderson M.T., A.A. Diaz, S.E. Cumblidge, and S.R. Doctor. 2007.Capabilities of Ultrasonic Techniques for Far-Side Examinations of Austenitic Stainless Steel Piping Welds. In Proceedings of the 5th International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, 1126-1138. Brussels:European Commission Joint Research Centre.PNNL-SA-49713.