Light Water Reactor Sustainability Program Framework for ...

1 INL/EXT-16-39903 Revision 0 Light Water Reactor Sustainability Program Framework for Structural Online Health Monitoring of Aging and Degradation of Secondary Systems due to some Aspects of Erosion September 2016 Department of Energy Office of Nuclear Energy DISCLAIMER This information was prepared as an account of work sponsored by an agency of the Government. Neither the Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness, of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. References herein to any specific commercial product, process, or service by trade name, trade mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Government or any agency thereof.

2 The views and opinions of authors expressed herein do not necessarily state or reflect those of the Government or any agency thereof. INL/EXT-16-39903 Revision 0 Framework for Structural Online Health Monitoring of Aging and Degradation of Secondary Systems due to some Aspects of Erosion Andrei Gribok, Sobhan Patnaik, Christian Williams, Marut Pattanaik, and Raghunath Kanakala September 2016 Prepared for the Department of Energy Office of Nuclear Energy Light Water Reactor Sustainability Program Framework for Structural Online Health Monitoring of Aging and Degradation of Secondary Systems due to some Aspects of Erosion INL/EXT-16-39903 Revision 0 September 2016 v ABSTRACT This report describes the current state of research related to critical aspects of erosion and selected aspects of degradation of secondary components in nuclear power plants (NPPs). The report also proposes a Framework for online health monitoring of aging and degradation of secondary components.

3 The Framework consists of an integrated multi-sensor modality system, which can be used to monitor different piping configurations under different degradation conditions. The report analyses the currently known degradation mechanisms and available predictive models. Based on this analysis, the structural health monitoring Framework is proposed. The Light Water Reactor Sustainability Program began to evaluate technologies that could be used to perform online monitoring of piping and other secondary system structural components in commercial NPPs. These online monitoring systems have the potential to identify when a more-detailed inspection is needed using real-time measurements, rather than at a pre-determined inspection interval. This transition to condition-based, risk-informed automated maintenance will contribute to a significant reduction of operations and maintenance costs that account for the majority of nuclear power generation costs. There is unanimous agreement between industry experts and academic researchers that identifying and prioritizing inspection locations in secondary piping systems (for example, in raw Water piping or diesel piping) would eliminate many excessive in-service inspections.

4 The proposed structural health monitoring Framework takes aim at answering this challenge by combining long-range guided wave technologies with other monitoring techniques, which can significantly increase the inspection length and pinpoint the locations that degraded the most. More widely, the report suggests research efforts aimed at developing, validating, and deploying online corrosion monitoring techniques for complex geometries, which are pervasive in NPPs. vi viiSUMMARY This report describes the technical Framework for online monitoring of secondary passive structures in nuclear power plants (NPPs) that is being conducted under the Department of Energy s Light Water Reactor Sustainability (LWRS) Program . The LWRS Program , funded by the Department of Energy s Office of Nuclear Energy, aims to provide scientific, engineering, and technological foundations for extending the life of operating Light Water reactors (LWRs).

5 This Program involves several goals, one of which is ensuring safe operation of NPPs passive components, such as concrete, piping, steam generators, heat exchangers, and cabling. Within the LWRS Program , the Advanced Instrumentation, Information, and Control (II&C) Systems Technologies Pathway conducts targeted research and development to address aging and reliability concerns with the legacy analog instrumentation systems, structures, and components (SSC) and related information systems of the operating LWR fleet. This work involves two major goals: (1) ensuring legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) to implementing digital II&C technology in a manner that enables broad innovation and business improvement in the NPP operating model. Resolving long-term operational concerns with II&C systems contributes to long-term Sustainability of the LWR fleet, which is vital to the nation s energy and environmental security. The goals of the LWRS Program are addressed through a number of pilot projects that target realistic opportunities for increasing Sustainability , safety, and economic efficiency of the existing NPP fleet.

6 It is generally recognized that the biggest challenge for existing NPPs is economic viability. Reducing operations and management cost is one of the most pressing problems facing the nuclear power generation industry. Operations and maintenance costs comprise approximately 60 to 70% of the overall generating cost in legacy NPPs. Only 15 to 30% of costs are attributed to fuel. Furthermore, of the operations and maintenance costs in plants, approximately 80% are labor costs. To address the issue of rising operating costs and economic viability, in 2016, companies that operate the national nuclear energy fleet started the Delivering the Nuclear Promise Initiative, which is a 3-year Program aimed at maintaining operational focus, increasing value, and improving efficiency. The Delivering the Nuclear Promise Initiative is also expected to play a key role in achieving one of the major goals of the Paris agreement signed in December 2015, which sets a long-term goal of limiting global warming to well below 2 C or C, if possible.

7 The United States would not be able to meet its obligation under the Paris agreement, which goes into force in 2020, if they close their existing NPPs. The biggest threat to the current nuclear fleet in the United States is economic challenges and not technical challenges. viii ix ACKNOWLEDGEMENTS The author would like to thank Heather Feldman and Kurt Crytzer of EPRI for their help and leadership in organizing the joint workshop on structural health monitoring and for providing technical guidance and feedback during the development of the joint research plan. The author is also grateful to Kenneth Thomas of INL for his insights and encouragements during technical discussions. x xi CONTENTS ABSTRACT .. v SUMMARY .. vii ACKNOWLEDGEMENTS .. ix ACRONYMS.

8 Xv 1. CAVITATION EROSION .. 1 Introduction .. 1 First Principles of Cavitation Erosion .. 1 Cavitation Erosion in Nuclear Power Plants .. 1 Wear Mechanism .. 2 Types of Cavitation .. 2 Cavitation Erosion in Various Materials and Their Behavior .. 3 Various Studies on Cavitation in NPPs .. 6 Erosion-Corrosion Occurring in NPPs .. 7 Erosion .. 7 Cavitation Corrosion .. 8 Synergetic Effect of Erosion and Cavitation Corrosion .. 8 Conclusion .. 10 2. LIQUID IMPINGEMENT EROSION .. 11 Introduction .. 11 First Principles of Liquid Impingement Erosion .. 11 The Phenomenon of Liquid Impingement .. 11 Liquid Impingement Erosion in NPPs and Other Areas .. 12 Conclusion .. 16 3. SOLID PARTICLE EROSION .. 16 Introduction .. 16 First Principles of Solid Particle Erosion .. 16 An Introduction to Solid Particle Erosion in NPPs .. 17 Mechanism of Solid Particle Erosion .. 17 Solid Particle Erosion in NPPs and Various Materials .. 18 Conclusion.

9 21 4. FLASHING EROSION .. 22 Introduction .. 22 First Principles of Flashing Erosion .. 22 How Flashing Occurs? A Case Study .. 22 Flashing vs. Cavitation .. 25 Effect of Flashing Erosion on Flow .. 25 More about Flashing .. 25 Controlling Flashing .. 26 The Flashing Phenomena .. 27 Measures against Flashing .. 27 Conclusion .. 27 5. PITTING CORROSION .. 28 Introduction .. 28 Mechanism of Pitting Corrosion .. 28 Factors Affecting Pitting Corrosion .. 28 6. PREDICTIVE MODELING OF EROSION .. 29 Predictive Modeling of Cavitation Erosion .. 29 Predictive Modeling of Liquid Impingement Erosion .. 33 Predictive Modeling of Solid Particle Erosion .. 36 Predictive Modeling of Pitting Corrosion .. 39 Prediction of Remaining Useful Life in NPPs .. 40 Conclusion .. 44 7. EROSION/CORROSION MONITORING TECHNIQUES .. 45 Introduction .. 45 Online Monitoring for Environmental 45 Online Monitoring Using FPGA/RT Technique.

10 45 Self-Diagnostic Monitoring System .. 46 Data Handling Technique for Non-Destructive Evaluation .. 48 Erosion-Corrosion Management System .. 48 Ultrasonic Intelligent Sensors from CLAMPON .. 48 Non-Destructive Technique from General Electric .. 49 Acoustic Emission Technique .. 52 Ultrasonic Monitoring .. 53 An Approach by IAEA .. 53 Wall Thinning Evaluation Method .. 56 Condition-Based Maintenance Technique .. 56 Using RAMEK Code as an Online Monitoring Approach .. 56 Impedance Monitoring Approach .. 57 Equipotential Switching Direct Current Potential Drop Approach .. 58 Electromagnetic Acoustic Resonance Technique .. 58 Condition-Based Inspections of Passive Components Enabled through Smart Online Monitoring .. 59 Definition Phase .. 62 Development Phase .. 63 Demonstration 64 Utility-Scale Testing Phase .. 64 xiii8. GUIDED WAVE TESTING .. 65 Introduction .. 65 Guided Waves Used as an NDT Method.