Detectability of intergranular stress corrosion cracking using field proven ultrasonic techniques

The authors first outline the problem raised by in-service ultrasonic detection of intergranular stress corrosion cracking (IGSCC), notably in pipe welds. They report a procedure improvement by using a 55-degree angle beam shear wave device, comment metallographic investigation results and their differences with respect to ultrasonic examinations. They evoke an investigation performed with the EPRI which led to the development of the 1,5 MHz examination for the detection of stress corrosion cracking. They discuss the difference between single and dual angle beam examination, report an indication analysis, show that a conical bore angle created for the weld preparation affects the examination beam, and describe the developed procedure and analysis for an examination through a conical bore. Finally, they describe how stress corrosion cracks can be identified