Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

On Dilation of the BN-350 Reactor Fuel Assemblies

9/25/2023 2023 - #03 Letters ti the editorial office

Zabud‘ko L.M.

DOI: https://doi.org/10.26583/npe.2023.3.15

UDC: 621.039.534:541.15

The irradiation conditions in a fast sodium reactor lead to a major dilation of the fuel assembly components: the hexagonal wrapper and the fuel cladding. The paper describes the development of the methodology for investigating the wrapper steel swelling and irradiation creep based on the specific features of the wrapper deformation. As a result of the statistical processing of experimental data from measuring the geometry of the BN-350 reactor spent fuel assembly wrappers in the cooling pond, dependences of the wrapper steel swelling and irradiation creep on the dose, temperature, and stresses caused by the coolant pressure were obtained for the first time. The results obtained in the BN-350 reactor for the 16Cr-11Ni-3Mo (annealed) wrapper steel, which was used in the starting core of the BN-600 reactor, have made it possible to adjust the fuel life before the BN-600 startup.

Currently, the BN-600 and BN-800 reactor fuel assembly wrappers are made of the EP450-Sh ferrite-martensitic steel and do not limit the fuel lifetime.


  1. Proshkin A.A., Zabudko L.M. Some Issues of Performance of Hexagonal Wrappers of Fast Reactors. Preprint IPPE-701. Obninsk. FEI Publ., 1976, 39 p.( in Russian).
  2. Proshkin A.A., Likhachev Yu.I., Tuzov A.A., Zabudko L.M., Bondarenko V.V., Karaulov V.N. Analysis of Experimental Data on Distortion Behavior of Fast Reactors Subassemblies. Atomnaya Energiya. 1981, v. 50, iss. 1, pp. 13-17 (in Russian).
  3. Zabudko L.M., Likhachev Yu.I., Proshkin A.A. Performance of Fast Reactors Subassemblies. Moscow. Energoatonizdat Publ., 1988,168 p. (in Russian).
  4. Karaulov V.N., Blynski A.P., Yakovlev I.L., Lambert J.D.B. Assembly and Fuel Pin Irradiation Behavior in the BN-350 Fast Reactor. Proc. of the ICONE8 (VIII-th International Conference on Nuclear Engineering), April 2-6, 2000, Baltimore, MD USA, No. 8394.
  5. Kozmanov E.A., Ogorodov A.N., Chuev V.V. Methodological support of Non-Destructive Post-Irradiation Examinations of the BN-600 Reactor Core Elements. Proc. of Scientific Papers «Study of Core Elements Structural Materials of Sodium Fast Reactors». Ekaterinburg. UrO RAN Publ., 1994, pp. 3-48. ISBN 5-7691-0473-2 (in Russian).
  6. Poplavskiy V.M., Zabudko L.M., Schkabura I.A., Skupov M.V., Bytchkov A.V., Kisliy V.A., Krukov F.N., Vasiliev B.A. Fuel for Advanced Sodium Fast Reactors – Current Status and Plans. Atomnaya Energiya. 2010, v. 108, iss. 4, pp. 212-216 (in Russian).

fast reactor BN-350 fuel assembly hexagonal wrapper dilation steel swelling irradiation creep cooling pool

Link for citing the article: Zabud‘ko L.M. On Dilation of the BN-350 Reactor Fuel Assemblies. Izvestiya vuzov. Yadernaya Energetika. 2023, no. 3, pp. 159-163; DOI: https://doi.org/10.26583/npe.2023.3.15 (in Russian).