| 2005 №10 (02) | 2005 №10 (04) |
The Paton Welding Journal, 2005, #10, 14-20 pages
Determination of residual stresses in the WWER vessels after multi-run welding, surfacing and high-temperature tempering
B.Z. Margolin, A.Ya. Varovin, V.I. Kostylyov
Central Research Institute of Structural Materials «Prometej», St.-Petersburg, RussiaAbstract
Calculations of residual stresses formed after welding, surfacing and tempering have been made for bodies of the water-moderated (WWER) type reactors. The calculation procedure is based on solutions of temperature and non-isothermal elastoplastic problems obtained using the finite elements method. α-Fe ↔ γ-Fe transformations and creep have been allowed for in solving the deformation problem. The investigations conducted show that the α-Fe ↔ γ-Fe transformation does have an effect on the distribution of residual stresses depending upon the conditions, under which this effect can be substantial, and under which it can be ignored.
Keywords: welding, surfacing, tempering, nuclear reactor, residual stresses, embrittlement, relaxation of stresses, calculation
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