PSI - Issue 57

ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000 Structural Integrity Procedia 00 (2022) 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 57 (2024) 833–847

© 2024 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 the scientific committee of the Fatigue Design 2023 organizers Based on the outcome of the lifetime study, different mitigation actions are proposed. Besides the reduction of operational gradients, a very interesting approach is to pro-actively machine the rotor surface before the onset of cracking. © 2023 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 the scientific committee of the Fatigue Design 2023 organizers Keywords: Lifetime estimation; thermomechanic fatigue; thermomechanic crack; stress control To manage the risk for the ENGIE fleet, with a wide variety of different steam turbine rotors, ENGIE Laborelec has developed a fleet risk management program. At the heart of this are numerical and finite element (FE) models, along with damage assessment methodologies that can offer estimates on the past and future lifetime consumption. Experience with cracked rotors provided the unique opportunity to calibrate the approach, enabling a more accurate prediction for the rest of the ENGIE fleet. Based on the outcome of the lifetime study, different mitigation actions are proposed. Besides the reduction of operational gradients, a very interesting approach is to pro-actively machine the rotor surface before the onset of cracking. © 2023 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 the scientific committee of the Fatigue Design 2023 organizers Keywords: Lifetime estimation; thermomechanic fatigue; thermomechanic crack; stress control Fatigue Design 2023 (FatDes 2023) Mitigating the risk for creep-fatigue cracking in steam turbine rotors: an end user’s perspective Malik Spahic a , Dario Guarino a , Clément Brichart a , Dieter Billet a , Frits Petit a, * a Engie Laborelec, Rue de Rhode 125, Linkebeek 1630, Belgium Abstract Over the last few years, cracks appeared at an early stage of operation on several steam turbine rotors due to low cycle fatigue damage induced by transient thermal events. These cracks led to expensive repair and associated unavailability of the units. A proper risk assessment is therefore key, especially given the expected increase in transient operation required from the conventional power plants in the future. To manage the risk for the ENGIE fleet, with a wide variety of different steam turbine rotors, ENGIE Laborelec has developed a fleet risk management program. At the heart of this are numerical and finite element (FE) models, along with damage assessment methodologies that can offer estimates on the past and future lifetime consumption. Experience with cracked rotors provided the unique opportunity to calibrate the approach, enabling a more accurate prediction for the rest of the ENGIE fleet. Fatigue Design 2023 (FatDes 2023) Mitigating the risk for creep-fatigue cracking in steam turbine rotors: an end user’s perspective Malik Spahic a , Dario Guarino a , Clément Brichart a , Dieter Billet a , Frits Petit a, * a Engie Laborelec, Rue de Rhode 125, Linkebeek 1630, Belgium Abstract Over the last few years, cracks appeared at an early stage of operation on several steam turbine rotors due to low cycle fatigue damage induced by transient thermal events. These cracks led to expensive repair and associated unavailability of the units. A proper risk assessment is therefore key, especially given the expected increase in transient operation required from the conventional power plants in the future.

1. Introduction 1. Introduction

* Corresponding author. Tel.: +32 474 258 309 ; fax: +0-000-000-0000 . E-mail address: frits.petit@engie.com * Corresponding author. Tel.: +32 474 258 309 ; fax: +0-000-000-0000 . E-mail address: frits.petit@engie.com

2452-3216 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers 2452-3216 © 2023 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 the scientific committee of the Fatigue Design 2023 organizers

2452-3216 © 2024 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 the scientific committee of the Fatigue Design 2023 organizers 10.1016/j.prostr.2024.03.090