PSI - Issue 22

Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

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ScienceDirect

Procedia Structural Integrity 22 (2019) 305–312

© 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers © 2019 The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers Keywords: Reactor Pressure Vessel (RPV); Pressurized Thermal Shock (PTS); Fracture Toughness (FT); Ductite to Brittle Transition Temperature (DBTT); Linear Elastic Fracture Mechanics (LEFM); Elestic-Plastic Fracture Mechanics (EPFM). Th miscon eptions of current m thodologies of RPV brittl fracture assessment ar described as well as recommendations for th y impr vements are given. It is hown, that some of problems (for nstanc claddi g integrity, modelling f weld residual tr sses, Fractur Toughness curve modificatio ) needs to be justificated, before they are con idered as a part of good-practice methodology f RPV integrity ass ssment. In particular, unreasonable high level of conservatism of Fracture Toughness curve specified in modern meth dologie i shown. And finally, for some of hem such s VERLIFE’s probabilistic embrittlement trend curve g neration and Maste -Curve approach for both det rmini tic a d probabilistic assessment, – ngineeri g inapplicability is demonstrated. Some improvements, such as chemical factor consideration and transition temperature determination for radiation embrittlem nt asses ment, proba ilistic RPV brittle fracture assessm nt e d veloped by “IPP - Centre” LLC a d briefly presented. © 2019 The Autho s. Publ shed by Elsev er B.V.This is an open access article u er the CC BY-NC-ND li ense (http://cr a ivecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers Keywords: Reactor Pressure Vessel (RPV); Pressurized Thermal Shock (PTS); Fracture Toughness (FT); Ductite to Brittle Transition Temperature (DBTT); Linear Elastic Fracture Mechanics (LEFM); Elestic-Plastic Fracture Mechanics (EPFM). First International Symposium on Risk and Safety of Complex Structures and Components Open issues in PTS assessment of WWER RPVs Мaksym Zarazovskii a, *, Yaroslav Dubyk a “ IPP-Centre ” LLC, 8 Bolsunovska str, Kyiv, 01014, Ukraine Abstract The main aim of the paper is the critical review of the current methodologies of WWER RPV brittle fracture assessment from the practical point of view. Design rules PNAE-G-7-002-86 and three modern approaches (Ukrainian MT-D.0.03.391-09, Czech and EU VERLIFE and Russian MRKR-SKhR-2004) are considered. Main issues of the modern methodologies are divided into two parts, that are related to computational fracture mechanics and to fracture characteristics (Fracture Toughness curve and Ductile to Brittle Transition Temperature) of metal of RPV beltline zone as well. The misconceptions of current methodologies of RPV brittle fracture assessment are described as well as recommendations for they improvements are given. It is shown, that some of problems (for instance cladding integrity, modelling of weld residual stresses, Fracture Toughness curve modification) needs to be justificated, before they are considered as a part of good-practice methodology of RPV integrity assessment. In particular, unreasonable high level of conservatism of Fracture Toughness curves specified in modern methodologies is shown. And finally, for some of them such as VERLIFE’s probabilistic embrittlement trend curve generation and Master-Curve approach for both deterministic and probabilistic assessment, – engineering inapplicability is demonstrated. Some improvements, such as chemical factor consideration and transition temperature determination for radiation embrittlement assessment, probabilistic RPV brittle fracture assessment are developed by “IPP - Centre” LLC and briefly presented. First International Symposium on Risk and Safety of Complex Structures and Components Open issues in PTS assessment of WWER RPVs Мaksym Zarazovskii a, *, Yaroslav Dubyk a “ IPP-Centre ” LLC, 8 Bolsunovska str, Kyiv, 01014, Ukraine Abstr ct The main aim of the paper is the critical review of the current methodologies of WWER RPV brittle fracture ssessment from the ractical point of view. Design rules PNAE-G-7-002-86 and three mod rn pproaches (Ukrainian MT-D.0.03.391-09, Cze h and EU VERLIFE a d Russi n MRKR-SKhR-2004) are considered. Main issues of the modern methodologies are divided into two parts, that are related to omputational fracture mechanics and to fracture characteristics (Fracture Toughness urve and Ductile to Brittle Transitio Temperature) of metal of RPV beltline zone as well.

* Corresponding author. Tel.: +38-066-709-72-14; fax: +3-044-502-4570. E-mail address: zarazovskiimaxim@ukr.net

2452-3216 © 2019 The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review statement: Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers 2452-3216 © 2019 The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review statement: Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers * Corresponding author. Tel.: +38-066-709-72-14; fax: +3-044-502-4570. E mail address: zarazovskiimaxim@ukr.net

2452-3216 © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers 10.1016/j.prostr.2020.01.039