Toward Robotic Inspection of Dry Storage Casks for Spent Nuclear Fuel

Extended dry storage of spent nuclear fuel makes it desirable to assess the structural integrity of the storage canisters. Stress corrosion cracking of the stainless steel canister is a potential degradation mode especially in marine environments. Sensing technologies are being developed with the aim of detecting the presence of chloride-bearing salts on the surface of the canister as well as whether cracks exist. Laser-induced breakdown spectroscopy (LIBS) methods for the detection of Chlorine are presented. In addition, ultrasonic-guided wave detection of crack-like notches oriented either parallel or perpendicular to the shear horizontal wave vector is demonstrated using the pulse-echo mode, which greatly simplifies the robotic delivery of the noncontact electromagnetic acoustic transducers (EMATs). Robotic delivery of both EMATs and the LIBS system is necessary due to the high temperature and radiation environment inside the cask where the measurements need to be made. Furthermore, the space to make the measurements is very constrained and maneuverability is confined by the geometry of the storage cask. In fact, a large portion of the canister surface is inaccessible due to the presence of guide channels on the inside of the cask's overpack, which is strong motivation for using guided waves for crack detection. Among the design requirements for the robotic system are to localize and track where sensor measurements are made to enable return to those locations, to avoid wedging or jamming of the robot, and to tolerate high temperatures and radiation levels.

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Robotic Inspection of Dry Storage Casks for Spent Nuclear Fuel

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2016-63312 ◽

2016 ◽

Cited By ~ 1

Author(s):

C. J. Lissenden ◽

S. Choi ◽

H. Cho ◽

A. Motta ◽

K. Hartig ◽

...

Keyword(s):

Nuclear Fuel ◽

Crack Detection ◽

Guided Waves ◽

Structural Integrity ◽

Spent Nuclear Fuel ◽

Radiation Environment ◽

Breakdown Spectroscopy ◽

Dry Storage ◽

Laser Induced Breakdown ◽

Horizontal Wave

Extended dry storage of spent nuclear fuel makes it desirable to assess the structural integrity of the storage canisters. Stress corrosion cracking of the stainless steel canister is a potential degradation mode especially in marine environments. Sensing technologies are being developed with the aim of detecting the presence of chloride-bearing salts on the surface of the canister as well as whether cracks exist. Laser induced breakdown spectroscopy (LIBS) methods for the detection of Chlorine are presented. Detection of a notch oriented either parallel or perpendicular to the shear horizontal wave vector is demonstrated using the pulse-echo mode, which greatly simplifies the robotic delivery of the noncontact electromagnetic acoustic transducers (EMATs). Robotic delivery of both EMATs and the LIBS system is necessary due to the high temperature and radiation environment inside the cask where the measurements need to be made. Furthermore, the space to make the measurement is very constrained and maneuverability is confined by the geometry of the storage cask. In fact, a large portion of the canister surface is inaccessible due to the presence of guide channels on the inside of the cask’s overpack, which is strong motivation for using guided waves for crack detection. Among the design requirements for the robotic system are: to localize and track where sensor measurements are made to enable return to those locations, to avoid wedging or jamming of the robot, and to tolerate high temperatures and radiation levels.

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Safety of Extended Dry Storage of Spent Nuclear Fuel SEDS2020: International online-workshop

Kerntechnik ◽

10.3139/124.020061 ◽

2020 ◽

Vol 85 (6) ◽

pp. 412-412

Author(s):

M. Stuke

Keyword(s):

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Dry Storage

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The Need for Integrating the Back End of the Nuclear Fuel Cycle in the United States of America

MRS Advances ◽

10.1557/adv.2018.231 ◽

2018 ◽

Vol 3 (19) ◽

pp. 991-1003 ◽

Cited By ~ 3

Author(s):

Evaristo J. Bonano ◽

Elena A. Kalinina ◽

Peter N. Swift

Keyword(s):

United States ◽

Nuclear Fuel ◽

United States Of America ◽

Spent Nuclear Fuel ◽

Fuel Cycle ◽

Nuclear Fuel Cycle ◽

The United States ◽

Spent Fuel ◽

Dry Storage ◽

The Us

ABSTRACTCurrent practice for commercial spent nuclear fuel management in the United States of America (US) includes storage of spent fuel in both pools and dry storage cask systems at nuclear power plants. Most storage pools are filled to their operational capacity, and management of the approximately 2,200 metric tons of spent fuel newly discharged each year requires transferring older and cooler fuel from pools into dry storage. In the absence of a repository that can accept spent fuel for permanent disposal, projections indicate that the US will have approximately 134,000 metric tons of spent fuel in dry storage by mid-century when the last plants in the current reactor fleet are decommissioned. Current designs for storage systems rely on large dual-purpose (storage and transportation) canisters that are not optimized for disposal. Various options exist in the US for improving integration of management practices across the entire back end of the nuclear fuel cycle.

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Rail Diagnostics Based on Ultrasonic Guided Waves: An Overview

Applied Sciences ◽

10.3390/app11031071 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1071

Author(s):

Davide Bombarda ◽

Giorgio Matteo Vitetta ◽

Giovanni Ferrante

Keyword(s):

Guided Waves ◽

Structural Integrity ◽

Diagnostic Procedures ◽

Guided Wave ◽

Rolling Stock ◽

Technical Literature ◽

Track Maintenance ◽

Rail Network ◽

Ultrasonic Guided Wave ◽

Maintenance And Inspection

Rail tracks undergo massive stresses that can affect their structural integrity and produce rail breakage. The last phenomenon represents a serious concern for railway management authorities, since it may cause derailments and, consequently, losses of rolling stock material and lives. Therefore, the activities of track maintenance and inspection are of paramount importance. In recent years, the use of various technologies for monitoring rails and the detection of their defects has been investigated; however, despite the important progresses in this field, substantial research efforts are still required to achieve higher scanning speeds and improve the reliability of diagnostic procedures. It is expected that, in the near future, an important role in track maintenance and inspection will be played by the ultrasonic guided wave technology. In this manuscript, its use in rail track monitoring is investigated in detail; moreover, both of the main strategies investigated in the technical literature are taken into consideration. The first strategy consists of the installation of the monitoring instrumentation on board a moving test vehicle that scans the track below while running. The second strategy, instead, is based on distributing the instrumentation throughout the entire rail network, so that continuous monitoring in quasi-real-time can be obtained. In our analysis of the proposed solutions, the prototypes and the employed methods are described.

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In-Service Inspection of Extended Dry Storage of Spent Nuclear Fuel, Part I: Crawler Technology Development

10.1115/pvp2021-62058 ◽

2021 ◽

Author(s):

Ryan M. Meyer ◽

Jeremy Renshaw ◽

Jamie Beard ◽

Jon Tatman ◽

Matt Keene ◽

...

Keyword(s):

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Technology Development ◽

Storage System ◽

Dry Storage ◽

Majority Population ◽

The Usa ◽

Extended Operation ◽

Interim Storage ◽

Physical Access

Abstract This paper describes development and demonstration of remote crawling systems to support periodic examinations of interim dry storage system (DSS) canisters for spent nuclear fuel in the USA. Specifically, this work relates to robotic crawler developments for “canister” based DSS systems, which form the majority population of DSSs in the USA for interim storage of spent nuclear fuel. Consideration of potential degradation of the welded stainless-steel canister in these systems is required for continued usage in the period of extended operation (PEO) beyond their initial licensed or certified terms. Challenges with performing the periodic examinations are associated with physical access to the canister surface, which is constrained due to narrow annulus spaces between the canister and the overpack, tortuous entry pathways, and high temperatures and radiation doses that can be damaging to materials and electronics. Motivations for performing periodic examinations and developing robotic crawlers for performing those examinations remotely will be presented, and several activities to demonstrate robotic crawlers for different DSS systems are summarized.

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Inservice Inspection of Extended Dry Storage of Spent Nuclear Fuel, Part II: NDE/Sensor Technology Development and Codification

10.1115/pvp2021-62069 ◽

2021 ◽

Author(s):

Ryan M. Meyer ◽

Jeremy Renshaw ◽

Kenn Hunter ◽

Mike Orihuela ◽

Jim Stadler ◽

...

Keyword(s):

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Technology Development ◽

Storage System ◽

Sensor Technology ◽

Nondestructive Examination ◽

Dry Storage ◽

Safety Function ◽

Majority Population ◽

The Usa

Abstract This paper describes development and demonstration of nondestructive examination (NDE) technologies to support periodic examinations of interim dry storage system (DSS) canisters for spent nuclear fuel in the USA to verify continued safe operation and that the canister confinement is intact and performing its intended safety function. Specifically, this work relates to NDE technology development for “canister” based DSS systems, which form the majority population of DSSs in the USA for interim storage of spent nuclear fuel. Consideration of potential degradation of the welded stainless-steel canister in these systems is required for continued usage in the period of extended operation (PEO) beyond the initial license or certified term. Physical access to the canister surface is constrained due to narrow annulus spaces between the canister and the overpack, tortuous entry pathways, and high temperatures and radiation doses that can be damaging to materials and electronics related to inspections. Several activities to demonstrate NDE technologies for the inspections of different DSS systems are summarized.

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Fatigue crack detection in pipes with multiple mode nonlinear guided waves

Structural Health Monitoring ◽

10.1177/1475921718791134 ◽

2018 ◽

Vol 18 (1) ◽

pp. 180-192 ◽

Cited By ~ 13

Author(s):

Ruiqi Guan ◽

Ye Lu ◽

Kai Wang ◽

Zhongqing Su

Keyword(s):

Fatigue Crack ◽

Crack Detection ◽

Guided Waves ◽

Second Harmonic ◽

Experimental Testing ◽

Harmonic Wave ◽

Guided Wave ◽

Element Analysis ◽

Fatigue Crack Detection ◽

Wave Modes

This study elaborates fundamental differences in fatigue crack detection using nonlinear guided waves between plate and pipe structures and provides an effective approach for analysing nonlinearity in pipe structures. For this purpose, guided wave propagation and interaction with microcrack in a pipe structure, which introduced a contact acoustic nonlinearity, was analysed through a finite element analysis in which the material nonlinearity was also included. To validate the simulation results, experimental testing was performed using piezoelectric transducers to generate guided waves in a specimen with a fatigue crack. Both methods revealed that the second harmonic wave generated by the breathing behaviour of the microcrack in a pipe had multiple wave modes, unlike the plate scenario using nonlinear guided waves. Therefore, a proper index which considered all the generated wave modes due to the microcrack was developed to quantify the nonlinearity, facilitating the identification of microscale damage and further assessment of the severity of the damage in pipe structures.

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