2022 №01 (06) DOI of Article
2022 №01 (08)

The Paton Welding Journal 2022 #01
The Paton Welding Journal, 2022, #1, 33-40 pages

Mathematical modeling of residual stresses in composite welded joints of WWER-1000 reactor vessel cover with CSS nozzles

A.A. Makarenko, O.V. Makhnenko

E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail:

Composite welded joints (CWJ) of the WWER-1000 reactor vessel cover with the nozzles of the control safety system (CSS) is the object of calculations of strength in the feasibility study of life extension of NPP power units. Kinetics of formation of residual stresses in welding CWJ of the WWER-1000 reactor vessel cover with the CSS nozzles and also their redistribution as a result of postweld heat treatment were calculated by mathematical modeling using finite element method. Effect of preheating on microstructural phase transformations in the HAZ of base material of the cover and nozzle was studied. The main features of residual stress distribution in CWJ after welding and after heat treatment were determined.
Keywords: composite welded joint, reactor vessel cover, WWER-1000, HAZ, microstructural phase transformations, residual stresses, heat treatment, mathematical modeling

Received: 30.10.2021
Accepted: 07.02.2022


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