| 2026 №05 (05) |
DOI of Article 10.37434/as2026.05.06 |
2026 №05 (07) |
"Avtomatychne Zvaryuvannya" (Automatic Welding), #5, 2026, pp. 45-59
Reliability assessment of welded structures of absorbing elements of control and protection systems of WWER-1000 and WWER-440 nuclear reactors (Review)
O.S. Milenin
, O.O. Makhnenko
E.O. Paton Electric Welding Institute of the NAS of Ukraine
11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.
E-mail: asmilenin@ukr.net
To ensure the safety of nuclear power plants in Ukraine, a crucial role is played by the Control and Protection Systems (CPS) with absorber elements (AE) ‒ the rod cluster control assembly (RCCA) of the WWER-1000 reactor and the extensions of the emergency control cassettes (ECC) of the WWER-440 reactor. The complexity of the operational impact on the AE, which are welded structures, necessitates an in-depth study of the physical and technological processes to ensure their structure integrity and reliability. Currently, the methods for predicting the limit state and service life of the AE elements in the CPS are insufficiently developed. This makes it impossible to extend the limited term of safe operation of these elements, which was assigned during the design of the nuclear power units. 50 Ref., 3 Tabl., 14 Fig.
Keywords: nuclear reactors, WWR-1000, WWER-440, control and protection system, absorber rods, emergency control cassette extensions, welded joints, term of safe operation
Received: 21.05.2026
Received in revised form: 31.07.2026
Accepted: 30.09.2026
Posted online: 20.10.2026
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Suggested Citation
O.S. Milenin, O.O. Makhnenko (2026) Reliability assessment of welded structures of absorbing elements of control and protection systems of WWER-1000 and WWER-440 nuclear reactors (Review). Automatic Welding, 05, 45-59. https://doi.org/10.37434/as2026.05.06Advertising in this issue:
