renshaw inspection and delivery systems for dry...

Inspection and Delivery Systems for Dry Canister Storage

System Inspection

© 2015 Electric Power Research Institute, Inc. All rights reserved.

Dr. Jeremy RenshawProject Manager

IEEE RoboResearch Seminar6 March 2015

System Inspection

Introduction

� Background– Spent fuel pools around the country are filling to

capacity

– Dry storage is currently the preferred choice for spent nuclear fuel

– Canisters may be in operation for 100 years, 300 years, or more

– Inspection options are critical to verify safe operation

2© 2015 Electric Power Research Institute, Inc. All rights reserved.

� Purpose– EPRI is coordinating efforts to maintain safe

operation of used fuel canisters

– One of these efforts is evaluation of NDE inspection and delivery options

� Implementation– EPRI Project underway to provide inspection and

delivery options for dry canister storage systems (DCSS)

Background

�Dry canister storage systems (DCSSs) were never designed for inspection– Developing inspection solutions

has proven challenging


�EPRI is working together with other entities to provide inspection options for DCSSs

Dry Storage Canister –See EPRI Report 1025209

EPRI Project on DCSS Inspection

�EPRI is focusing on 4 main areas– Collaborations

– Mockups

– NDE Technologies

– Delivery SystemsCanisterCanister

OverpackOverpack

Vents (Green)Vents (Green)


– Delivery Systems

�End goal is to demonstrated NDE techniques with a functional delivery system

Snake Robot with Snake Robot with NDE PayloadNDE Payload

Potential inspection option for a DCSS

EPRI Collaborations

�Significant collaborative efforts and industry interest managed via the Extended Storage Collaboration Program (ESCP) NDE Subcommittee– Monthly calls and face-to-face meetings 2X per year

� Toll-Free Number: 877-458-6014� Participant PIN: 8660

�Working with 13 Universities, 10 Utilities, 7 National Labs, 7 Inspection vendors, 3 cask vendors, NRC, and NEI


Inspection vendors, 3 cask vendors, NRC, and NEI – Preparing NEUP/IRP proposals to leverage DOE funds (an EPRI-

supported team was selected for the latest $3M funding opportunity)– Working with other universities on NDE inspection & delivery

�Proposing collaborative projects related to DCSS inspection– EDF Energy on inspection ring concept– University of South Carolina on acoustic emission– INL on volatile corrosion inhibitors

EPRI Mockups

�Existing mockups around the country have been identified – None have flaws

– Some cannot have flaws

– Some sites have canisters only and others have the overpack as well

�EPRI has been working with flaw


�EPRI has been working with flaw mockup manufacturers to build 8 QA flaw mockups for industry use.– Final mockups complete with a

range of flaw sizes and orientations

– Additional related mockups available

DCSS Environment

�DCSS are a challenging environment for NDE and robotics– Radiation dose from 1-10,000 R/hr

– “Typical” temperatures from ~70-176+°F (~21-80+°C)

� Possibly up to ~250°F (~120°C)

– Challenging access

� Small vent ports for access


� Narrow annulus between canisters and concrete overpack

Qualitative Overview of NDE Techniques

NDE Technique

Temperature

Resistant

Radiation

Resistant

Small Form

Factor

Sensitive to

ODSCC

Compatibility for

DCSS Inspection

Time to

Delivery

Visual (VT)

Eddy Current Testing (ECT)

Ultrasonic Testing (UT)

EMAT/Guided Waves (GW)

Acoustic Emission (AE)

X-ray (RT)

Penetrant Testing (PT) N/A

Thermography


Muon Imaging

Now Not Applicable

< 1 year Good Performance / Yes

< 3 years Fair Performance / Maybe

4+ years or N/A Poor Performance / Not Well Suited

Desire is to have qualified NDEtechniques, such as UT or ECT

Eddy Current Array Results

�Results obtained in collaboration with– Eddyfi (probe manufacturer)

– UNCC (senior design project)


NDE Delivery

�The NDE inspection options are relatively well understood– NDE is not expected to be the primary

challenge

�Delivery of an NDE payload into a confined space environment under high temperature and high radiation


high temperature and high radiation is much more challenging– The delivery system is the major

challenge

– No techniques are available for inspection and delivery today

NDE Delivery System

�Easiest delivery option is to remove the canister from the overpack– Highly undesirable due to lifting a nuclear load– Cannot simply remove the canister from the overpack

�Robotic delivery of NDE equipment into the canister is preferred– Robotic delivery options have been identified – Additional delivery options were solicited in an RFP


NDE Delivery

�EPRI initiated an RFP for robotic delivery systems and associated NDE equipment for inspecting canisters

�15 responses received– 4 robotic and/or NDE finalists– RFP award to Robotic Technologies of

Tennessee (RTT) and Structural Integrity


Tennessee (RTT) and Structural Integrity Associates (SIA)

NDE Delivery

�Working with RTT on robotic delivery ideas– Two envisioned concepts are below

– Both have the capability to drive over 90°bends and traverse the DCSS vertically and horizontally


NDE Delivery

�Two preliminary designs are below– Vacuum Suction robot (left) manufactured using a 3D printer– Magnetic wheel robot (right) with the eddy current array inspection

system attached�Must manufacture robots to be compatible with a high-

temperature, high-radiation (nuclear) environment– Need to avoid certain materials, designs, etc.– Absolutely cannot leave anything behind


Proposed Phased Approach:

DCSS Inspection Timeline

Robot

#1

20162015 2017

EC Array

#2 #3 #4

2018Prototype

Development

Laboratory Testing

#5


Proposed Phased Approach:

1. Testing on a canister mockup

2. Potential testing at Palo Verde mockup

3. Test on an unloaded canister

4. Temperature testing and field preparation

5. Delivery to a utility site

Technology transfer to the industry is the goal

Summary

� EPRI is working towards solutions to the DCSS inspection issue via:

– Collaboration

– Mockup Fabrication

– NDE Development

– Robotic Delivery

� EPRI is coordinating efforts between different institutions (Utilities, National Labs, Vendors, EPRI, NRC, etc.)

� QA Flaw Mockups to be fabricated


� NDE methods are under investigation to provide inspection solutions

� Robotic development project is underway

� NDE Subcommittee provides monthly updates with the latest information

– Meeting is on the 1st Thursday of each month from 11:00-11:30 EST

– Toll-Free Number: +1-877-458-6014

– Participant PIN: 8660

Together…Shaping the Future of Electricity


Together…Shaping the Future of Electricity

renshaw inspection and delivery systems for dry...

Documents