Avtomaticheskaya Svarka (Automatic Welding), #4, 2016, pp. 35-41
Modelling of residual stresses, radiation swelling and stressed state of in-service WWER-1000 reactor baffle
O.V. Makhnenko, I.V. Mirzov and V.B. Porokhonko
E.O. Paton Electric Welding Institute, NASU 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: email@example.com
The question of effect of baffle residual welding stresses on radiation swelling value has appeared in course of works on
life extension of WWER-1000 reactor internals at the second power generating unit of the South-Ukrainian NPP. The
E.O. Paton Electric Welding Institute has developed and realized a mathematical model for determination of residual
stress-strain state of WWER-1000 reactor baffle in electroslag welding with further heat treatment as well as a model
for calculation of baffle radiation swelling taking into account radiation creep. It can be stated based on the results of
mathematical modelling that the baffle stressed state after 60 years of operation, calculated taking into account residual
welding stresses, is close to the results received using the model without welding. This work studies relaxation of residual
welding stresses in the WWER-1000 baffle under effect of irradiation and works out their in-service value-to-time
dependence. 15 Ref., 3 Tables, 11 Figures.
WWER-1000, baffle, electroslag welding, residual welding stresses, heat treatment, radiation swelling,
radiation creep, mathematical modelling
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