Reliability and results, but little room to manoeuvre

A wide variety of research programs to produce cost-effective and reliable inspection techniques have arisen following the discovery of stress corrosion cracks in the control rod drive mechanism of pressurized water reactors, notably in France, Belgium and Spain. This article describes the research program results from a cooperative partnership between Comex Nucleaire, Westinghouse Electric and AEA Technology. The package developed offers techniques to provide complete capability in virtually all the design configurations used world-wide. After extensive acceptance trials in France and the United States the techniques are now being used on site at Bugey 3. (UK)