Основні вимоги до TLAA та практика їх застосування в Україні та світі

• Дата: 2021
• Автори: Shugailo, O-i, Kazymyrska, O., Brik, D., Chumel, B., Banko, S.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: State Scientific and Technical Center for Nuclear and Radiation Safety 2021
• Онлайн доступ: https://nuclear-journal.com/index.php/journal/article/view/788
• Назва журналу: Nuclear and Radiation Safety

Aging management (AM) is considered to be one of the main factors in ensuring safe operation of nuclear power plants (NPPs) at the stages of design and long-term operation (LTO). As defined by the IAEA, aging management for NPPs is carried out in order to reduce the impact of aging effects on the performance of structures, systems and components (SSCs) of their design safety functions during the service life of NPP (including decommissioning). It requires taking into account both the consequences of physical aging of SSCs, which lead to performance deterioration, and non-physical aging of SSCs (its aging in comparison with the current state of development of science and technology). Therefore, the analysis of the state of the AM issue is given appropriate attention both in Ukraine and in the world. One of the main components of aging management is the performance of Time Limited Aging Analysis (TLAA). In fact, it is the TLAA results that can be interpreted as the lifetime of a particular component or structure. This article presents the main requirements and criteria for successful application of TLAA according to the IAEA recommendations, presents the main results of practical application analysis of TLAA in Europe and the United States (approaches to assessing aging and methodology for developing AM programs are analyzed). The experience of Ukraine in transition to LTO based on TLAA is analyzed, typical TLAA are considered, which are performed during the periodic safety reassessment to justify the LTO of Ukrainian NPPs (resistance to brittle fracture of the RPV, fatigue / assessment of the reactor main seal cyclic strength, stress relaxation of prestressed steel tendons of containment). In addition, the article compares national and international approaches to requirements of TLAA, and also draws appropriate conclusions.