A characterization of check valve degradation and failure experience in the nuclear power industry: 1991 Failures, Volume 2

Check valves are critical components in the operation of current generation nuclear power plants and may serve an increasingly critical role in the designs of future advanced passive light water reactors. Recognizing that check valve failures can result in significant operating transients, increased maintenance costs, and/or decreased system availability, the nuclear industry has taken a proactive approach to failure detection and prevention. As part of the Nuclear Regulatory Commission`s (NRC`s) program to evaluate the effects of age and wear on nuclear systems components, Oak Ridge National Laboratory (ORNL) has analyzed hundreds of check valve failures in safety-related applications. This research, combined with efforts by industry, regulatory, and codes and standards organizations, has provided insight into check valve performance history and may be used to provide a basis for evaluation of changes to utilities inservice test and inspection practices.