Davis-Besse vessel head replacement underway

06 October 2011

Work has begun to replace the reactor vessel head at FirstEnergy Nuclear Operating Company's (Fenoc's) Davis-Besse nuclear power plant in Ohio. The plant has suffered problems with cracking caused by stress corrosion around control rod drive mechanism nozzles, which necessitated modifications to 24 out of the 69 nozzles during the plant's maintenance outage in early 2010. Following that experience, Fenoc decided to bring the vessel head replacement forward from the originally planned date of 2014. The new head, manufactured in France by Areva, features control rod nozzles made of a material less susceptible to cracking. A new reactor control system will also be installed during the current maintenance outage.