Published Online: 25 October 2007
Page Count: 12
Hall, J. Brian
AREVA NP Inc., Lynchburg, Virginia
Spond, Dan F.
Entergy Operations, Russellville, Arkansas
(Received 3 November 2006; accepted 17 September 2007)
The B&W Owners Group Master Integrated Reactor Vessel Surveillance Program (MIRVP) was initiated in 1977 for the B&W 177 fuel assembly (FA) plants. Its purpose was to augment the existing reactor vessel surveillance programs and provide a basis for sharing information between plants. All of the early vintage B&W-manufactured reactor vessels were fabricated using the submerged arc welding process and particular consumables, which resulted in welds that are sensitive to fast-neutron exposures. The welds in these vintage B&W-manufactured reactor vessels are referred to as the Linde 80 class of materials. In 1988, the MIRVP was further modified to include a series of plants with the Westinghouse Nuclear Steam Supply System for which B&W manufactured the reactor vessels. These vessels have virtually identical welds as those used in the B&W 177 FA plants. The overall objective of the MIRVP is to provide the data necessary to ensure compliance with U.S. Federal Regulations. With the extension of operating licenses to 60 years for many of the member plants, the program was re-evaluated to ensure that data will be available for 60 and 80 years of operation. Projected reactor vessel fluence levels at 60 and 80 years were compared to available data and projected irradiations of the surveillance capsules that continue to be irradiated. This paper presents an overview of the MIRVP, data evaluation, results, and the withdrawal schedule adjustments. The program has adequate surveillance capsules to meet the irradiation needs of the participating plants for 80 years; however, the planned withdrawal schedule has been adjusted.
Paper ID: JAI100730