Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

Full text (ua)

O. V. Grytsenko¹, V. N. Bukanov¹, O. G. Vasylieva¹, V. L. Diemokhin¹, О. M. Pugach^1,*, V. M. Revka¹, O. V. Trygubenko², E. M. Chalyi², Yu. V. Chaikovskyi<sup>1

1</sup> Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
² Affiliate "SS "Scientific and Technical Centre" JSC "NNEGC "Energoatom", Kyiv, Ukraine

^*Corresponding author. E-mail address: o.m.pugach@gmail.com

Abstract: The surveillance program is an important source of information on the change in the properties of the metal of the water-water power reactor pressure vessel during operation. The regular program carried out at the power units of the Ukrainian NPPs provides material science support for the safe operation of the VVER-1000 pressure vessel until the end of the designated service life. Therefore, regulatory documents in force in the nuclear power industry of Ukraine require the development and implementation of additional surveillance programs, which would, first of all, ensure the earlier irradiation of surveillance specimens compared to the reactor pressure vessel. To solve this problem, the programs for modernization of single-floor container assemblies with specimens that are irradiated at regular locations in the VVER-1000 reactors have been developed. The transition of Ukrainian NPPs to Westinghouse nuclear fuel requires updating these programs. For now, one of the programs for the modernization of single-floor container assemblies has been implemented at one of the power units with a VVER-1000 reactor.

Keywords: VVER-1000, container assembly, reactor pressure vessel, surveillance program, lifetime extension period, fuel manufactured by the Westinghouse company, neutron fluence.

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