MRP-227/228 component inspections supporting nuclear power plant license renewal

•Inspections meeting the new requirements of MRP-227/228 are presented.•These inspections allow utilities to comply with requirements for license extension.•Modeling results for UT inspection methods are presented.•Defects down to 1% cross-sectional area were detected in a blind demonstration.•All MRP-required demonstrations were successfully passed. As the world’s nuclear reactor fleet continues to age, the importance of verifying the structural integrity of critical reactor components and systems has continued to increase. Some critical components are the reactor internals found in close proximity to the nuclear fuel rods which are exposed not only to high stresses and temperatures, but also to high radiation and neutron fluxes. The Materials Reliability Program (MRP-227/228) has provided guidance indicating which components are of the highest importance and susceptibility to the aging mechanisms found in nuclear reactors. These components must be either inspected or replaced in order for plants to be granted license renewals to continue commercial operations. Several inspection methods are presented that were successfully demonstrated and comply with these new guidelines to meet the requirements for license renewal.