Risk-effective optimal maintenance regime for a periodically tested safety component subjected to imperfect repairShow others and affiliations
2025 (English)In: Annals of Nuclear Energy, ISSN 0306-4549, E-ISSN 1873-2100, Vol. 211, article id 110902Article in journal (Refereed) Published
Abstract [en]
In this study, the risk-effectiveness framework proposed in NUREG/CR-5775 is developed based on the authors’ previously proposed Reliability, Availability, and Maintainability (RAM) model, which comprehensively considers all significant factors, including aging effects, test-caused degradation, test efficiency, and maintenance effectiveness. The developed RAM-based risk-effectiveness criterion, along with the Risk Management Technical Specification (RMTS) framework (RG 1.174 and 10 CFR 50.65(a)), is incorporated as a constraint in the optimization problem of surveillance test and maintenance (ST&M) planning for safety-related components in NPPs. As an application, the maintenance regime for a Motor-Operated Valve within the High-Pressure Injection System of a VVER/1000-V446 NPP, subjected to periodic tests and imperfect repairs, is optimized based on equipment RAM and its risk impact (ΔCDF) at the plant level. The results demonstrate that the most rational optimal ST&M planning must be determined as harmonizing and simultaneously positioning within the broad risk-effectiveness margin while also satisfying the criteria outlined in the RMTS framework. The proposed framework can provide valuable insights to maintenance decision-makers to evaluate and select appropriate maintenance strategies.
Place, publisher, year, edition, pages
Elsevier, 2025. Vol. 211, article id 110902
Keywords [en]
Optimization, Surveillance Test and Maintenance (ST&M), RAM Model, Imperfect Repair or Maintenance, Risk-Management Technical Specification (RMTS), Risk-Effectiveness, Probabilistic Safety Assessment (PSA), Ageing, Degradation
National Category
Reliability and Maintenance
Research subject
Operation and Maintenance Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-110078DOI: 10.1016/j.anucene.2024.110902ISI: 001316856500001Scopus ID: 2-s2.0-85203658347OAI: oai:DiVA.org:ltu-110078DiVA, id: diva2:1900381
Note
Validerad;2024;Nivå 2;2024-11-26 (signyg);
2024-09-232024-09-232025-10-21Bibliographically approved