Досвід обстеження опроміненого ядерного палива на АЕС України за допомогою стенду інспекції і ремонту палива

• Дата: 2022
• Автори: Zuyok, V., Krasnorutskyy, V., Grytsyna, V., Rud, R., Tretyakov, M., Kyshtym, Ya., Hrudnytskyy, V., Zigunov, V., Slyeptsov, O., Kasperovych, I., Solovyov, Yu., Medintsov, V., Glushenkov, R.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: State Scientific and Technical Center for Nuclear and Radiation Safety 2022
• Онлайн доступ: https://nuclear-journal.com/index.php/journal/article/view/972
• Назва журналу: Nuclear and Radiation Safety

Fuel Inspection and Repair Equipment (FIRE) was produced by the Westinghouse Company for SE “NNEGC” Energoatom to inspect fuel assemblies (FAs). Experts from Separated Subdivision “Atomremontservis” and Science and Technology Establishment “Nuclear Fuel Cycle” developed and verified methods for processing the results of FA inspection obtained using FIRE and carried out a set of activities on FIRE modification to provide the possibility of inspection of fuel assemblies manufactured by the TVEL Company and detect fuel assemblies with deformation. It is shown that the FIRE equipment, developed methods and modifications allow obtaining the data that characterize the integrity of fuel rods and fuel assemblies operated at Ukrainian NPPs with VVER‑1000/320. Based on the results of examining about 86 Westinghouse FAs (WFA, RWFA) and 10 TVEL FAAs it was concluded that the obtained values of the parameters characterizing the integrity of FAAs and W/RWFAs do not exceed the limits set at the stage of fuel design and safety justification of fuel loading, in which the indicated fuel assemblies were operated. All FAs, whose scheduled inspection was conducted after 1-3 years of operation were loaded in the following fuel cycles. The values of the parameters characterizing the integrity of FAAs and W/WRFAs after four fuel cycles indicate that nuclear fuel service life is not expired and nuclear fuel has a sufficient margin of controlled parameters to achieve higher burnup. Additional inspection types are proposed, which are necessary for better understanding the main factors that allow establishing the reliability margin of FAs regarding different types of leakage and developing recommendations for improvement of safety and efficiency of fuel operation, namely control of fuel rod cladding deformation depending on burnup, control of contact points of the cladding with spacer grids produced of zirconium and nickel-chromium alloys.