By: Scott Chesworth (SI) and Bob Grizzi (EPRI)
The goal was to determine whether the frequency of current inspection requirements was justified or could be optimized (i.e., increase the interval of certain inspections to devote more attention to higher-value inspections and thereby maximize overall plant safety).
Welds and similar components in nuclear power plants are subjected to periodic examination under ASME Code, Section XI. Typically, examinations are performed during every ten-year inspection interval using volumetric examination techniques, or a combination of volumetric and surface examination techniques. Nuclear plants worldwide have performed numerous such inspections over plant history with few service induced flaws identified.