PSI - Issue 68

ScienceDirect Structural Integrity Procedia 00 (2025) 000–000 Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 68 (2025) 915–921

European Conference on Fracture 2024 A new concept for large-scale pressure systems structural integrity computations Tamás Fekete a, * a HUN-REN Centre for Energy Research, H-1121 Budapest, Konkoly-Thege Str.29-33., Hungary European Conference on Fracture 2024 A new concept for large-scale pressure systems structural integrity computations Tamás Fekete a, * a HUN-REN Centre for Energy Research, H-1121 Budapest, Konkoly-Thege Str.29-33., Hungary

Abstract Generating electricity in an efficient and environmentally friendly manner is one of the most pressing issues facing the energy industry today. For this reason, and for the stability of the energy supply system, Nuclear Power Plants are of particular importance. The Large-Scale Pressure Systems in the Reactor Coolant Systems of Pressurized Water Reactor Nuclear Power Plants are a key part of both the operating and protection systems. The HUN-REN Centre for Energy Research is currently developing a new concept-based methodology for future Structural Integrity Calculations of Large-Scale Pressure Systems. The theory based on the novel concept opens the possibility of integrating complex, thermodynamically consistent aging, damage and fracture models into future Structural Integrity Calculations of Large-Scale Pressure Systems. This will greatly increase the reliability of calculations supporting the extension of nuclear unit lifetimes into the LTO range. This paper outlines the methodology for building the new concept. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers Keywords: Structural Integrity; Structural Integrity Calculations; Research Methodology; Concept; Coceptual shift 1. Introduction ‘ In today's” technologically advanced “societies, it has become possible for an ever-increasing number of individuals to pursue a’ lifestyle that is free of the burden of extremely demanding daily physical work and overwhelming material ‘ want .’ – Simonyi (2012 1.). The level of material prosperity now within the reach of an Abstract Generating electricity in an efficient and environmentally friendly manner is one of the most pressing issues facing the energy industry today. For this reason, and for the stability of the energy supply system, Nuclear Power Plants are of particular importance. The Large-Scale Pressure Systems in the Reactor Coolant Systems of Pressurized Water Reactor Nuclear Power Plants are a key part of both the operating and protection systems. The HUN-REN Centre for Energy Research is currently developing a new concept-based methodology for future Structural Integrity Calculations of Large-Scale Pressure Systems. The theory based on the novel concept opens the possibility of integrating complex, thermodynamically consistent aging, damage and fracture models into future Structural Integrity Calculations of Large-Scale Pressure Systems. This will greatly increase the reliability of calculations supporting the extension of nuclear unit lifetimes into the LTO range. This paper outlines the methodology for building the new concept. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers Keywords: Structural Integrity; Structural Integrity Calculations; Research Methodology; Concept; Coceptual shift 1. Introduction ‘ In today's” technologically advanced “societies, it has become possible for an ever-increasing number of individuals to pursue a’ lifestyle that is free of the burden of extremely demanding daily physical work and overwhelming material ‘ want .’ – Simonyi (2012 1.). The level of material prosperity now within the reach of an © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers

* Corresponding author. Tel.: +36 1 392 2222 / 3403; fax: +36 1 395 9293. E-mail address: fekete.tamas@ek.hun-ren.hu * Corresponding author. Tel.: +36 1 392 2222 / 3403; fax: +36 1 395 9293. E-mail address: fekete.tamas@ek.hun-ren.hu

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers 2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers 10.1016/j.prostr.2025.06.150