NRC STAFF PLEASE PRINT AND BRING A HARDCOPY IF YOU …Hearing Identifier:...

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From: Holonich, JosephSent: Monday, July 18, 2016 9:04 PMTo: Poehler, Jeffrey; Hiser, Allen; Hardies, Robert; Mchale, John; Amberge, Kyle; 'Ostroff,

James'; Burgos, Brian; Cheruvenki, Ganesh; Tilton, Caroline; John J. Sipos; Mihir Desai; '[email protected]'; 'Bergman, Jana'; Kuhlmann, Jenny

Cc: Hsueh, Kevin P; 'Molkenthin, James P'; 'Michael F Marino (Generation - 4)'; 'Demma, Anne'; 'Rudell, Bernie C:(GenCo-Nuc)'; 'Malikowski, Heather M:(GenCo-Nuc)'; 'Glenn A Gardner (Generation - 4)'; 'Wells, Tim G.'; 'Dyle, Robin'; Ross-Lee, MaryJane; Gray, Mel; Dentel, Glenn; Floyd, Niklas; Kulp, Jeffrey; Burket, Elise; Mangan, Kevin; Laur, Steven; Lyons, Sara; Clifford, Paul; Hickey, James; Alley, David; Haagensen, Brian; Ziedonis, Adam; Bower, Fred; Barkley, Richard; Siwy, Andrew; Draxton, Mark; Vadella, Robert; Finney, Patrick; R1DRPBR3CAL RESOURCE; Rudland, David; Nove, Carol; Turk, Sherwin; Wallace, Jay; Butcavage, Alexander; Werner, Greg; Anchondo, Isaac A; Drake, James; Hills, David; Holmberg, Mel; Fernandez, Edison; Schmidt, Colleen; Riemer, Kenneth; Ellegood, John; Taylor, Thomas; Cender, Laura; Domke, Matthew; Neurauter, James; Smith, Laura; Garg, Krishan

Subject: Background Information for Jul 19, 2016 Meeting on Baffle Former Bolts is attached. NRC staff needs to print their copy.

Importance: High

Below is the background information for the Jul 19, 2016 meeting baffle former bolts. NRC STAFF PLEASE PRINT AND BRING A HARDCOPY IF YOU WANT A COPY. THERE WILL BE LIMITED COPIES AVAILABLE IN THE MEETING ROOM AND THOSE ARE FOR STAKEHOLERS.

Hearing Identifier: IndianPointUnits2and3NonPublic_EX Email Number: 7475 Mail Envelope Properties (32dc897f00c142a69db50ae12d4df056) Subject: Background Information for Jul 19, 2016 Meeting on Baffle Former Bolts is attached. NRC staff needs to print their copy. Sent Date: 7/18/2016 9:03:42 PM Received Date: 7/18/2016 9:03:55 PM From: Holonich, Joseph Created By: [email protected] Recipients: "Hsueh, Kevin P" <[email protected]> Tracking Status: None "'Molkenthin, James P'" <[email protected]> Tracking Status: None "'Michael F Marino (Generation - 4)'" <[email protected]> Tracking Status: None "'Demma, Anne'" <[email protected]> Tracking Status: None "'Rudell, Bernie C:(GenCo-Nuc)'" <[email protected]> Tracking Status: None "'Malikowski, Heather M:(GenCo-Nuc)'" <[email protected]> Tracking Status: None "'Glenn A Gardner (Generation - 4)'" <[email protected]> Tracking Status: None "'Wells, Tim G.'" <[email protected]> Tracking Status: None "'Dyle, Robin'" <[email protected]> Tracking Status: None "Ross-Lee, MaryJane" <[email protected]> Tracking Status: None "Gray, Mel" <[email protected]> Tracking Status: None "Dentel, Glenn" <[email protected]> Tracking Status: None "Floyd, Niklas" <[email protected]> Tracking Status: None "Kulp, Jeffrey" <[email protected]> Tracking Status: None "Burket, Elise" <[email protected]> Tracking Status: None "Mangan, Kevin" <[email protected]> Tracking Status: None "Laur, Steven" <[email protected]> Tracking Status: None "Lyons, Sara" <[email protected]> Tracking Status: None "Clifford, Paul" <[email protected]> Tracking Status: None "Hickey, James" <[email protected]> Tracking Status: None

"Alley, David" <[email protected]> Tracking Status: None "Haagensen, Brian" <[email protected]> Tracking Status: None "Ziedonis, Adam" <[email protected]> Tracking Status: None "Bower, Fred" <[email protected]> Tracking Status: None "Barkley, Richard" <[email protected]> Tracking Status: None "Siwy, Andrew" <[email protected]> Tracking Status: None "Draxton, Mark" <[email protected]> Tracking Status: None "Vadella, Robert" <[email protected]> Tracking Status: None "Finney, Patrick" <[email protected]> Tracking Status: None "R1DRPBR3CAL RESOURCE" <[email protected]> Tracking Status: None "Rudland, David" <[email protected]> Tracking Status: None "Nove, Carol" <[email protected]> Tracking Status: None "Turk, Sherwin" <[email protected]> Tracking Status: None "Wallace, Jay" <[email protected]> Tracking Status: None "Butcavage, Alexander" <[email protected]> Tracking Status: None "Werner, Greg" <[email protected]> Tracking Status: None "Anchondo, Isaac A" <[email protected]> Tracking Status: None "Drake, James" <[email protected]> Tracking Status: None "Hills, David" <[email protected]> Tracking Status: None "Holmberg, Mel" <[email protected]> Tracking Status: None "Fernandez, Edison" <[email protected]> Tracking Status: None "Schmidt, Colleen" <[email protected]> Tracking Status: None "Riemer, Kenneth" <[email protected]> Tracking Status: None "Ellegood, John" <[email protected]> Tracking Status: None "Taylor, Thomas" <[email protected]> Tracking Status: None "Cender, Laura" <[email protected]> Tracking Status: None "Domke, Matthew" <[email protected]> Tracking Status: None "Neurauter, James" <[email protected]> Tracking Status: None

"Smith, Laura" <[email protected]> Tracking Status: None "Garg, Krishan" <[email protected]> Tracking Status: None "Poehler, Jeffrey" <[email protected]> Tracking Status: None "Hiser, Allen" <[email protected]> Tracking Status: None "Hardies, Robert" <[email protected]> Tracking Status: None "Mchale, John" <[email protected]> Tracking Status: None "Amberge, Kyle" <[email protected]> Tracking Status: None "'Ostroff, James'" <[email protected]> Tracking Status: None "Burgos, Brian" <[email protected]> Tracking Status: None "Cheruvenki, Ganesh" <[email protected]> Tracking Status: None "Tilton, Caroline" <[email protected]> Tracking Status: None "John J. Sipos" <[email protected]> Tracking Status: None "Mihir Desai" <[email protected]> Tracking Status: None "'[email protected]'" <[email protected]> Tracking Status: None "'Bergman, Jana'" <[email protected]> Tracking Status: None "Kuhlmann, Jenny" <[email protected]> Tracking Status: None Post Office: HQPWMSMRS01.nrc.gov Files Size Date & Time MESSAGE 263 7/18/2016 9:03:55 PM Agenda Jul 19, 2016 BFB Meeting.pdf 57828 1- Summary and Discussion of Recent BFB Inspections.pdf 869624 2- Industry Assessment of BFB Inspection Findings - WEC.pdf 104309 3 - Industry Assessment of BFB Inspection Findings - AREVA.pdf 300185 4 - Charter and Objectives of Industry BFB Focus Group.pdf 751798 5 - Next Industry Steps and Ongoing Related Efforts.pdf 514801 Baffle-Former Bolts Public Meeting July 19 NRC Slides.pptx 324516 Options Priority: High Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date: Recipients Received:

Agenda for U.S. Nuclear Regulatory Commission (NRC) Staff and Electric Power Research Institute (EPRI) on Recent Inspection/Operating Experience with Baffle-Former-Bolts (BFB) and

MRP-227-A, “Pressurized Water Reactor Internals Inspection and Evaluation Guidelines”

July 19, 2016 (Category 1 Public Meeting)

Time Agendum Lead

8:30 a.m. Introduction, Safety, Administration, Opening Remarks NRC Staff/EPRI

8:45 a.m. Summary Recent Inspections of BFBs - DC Cook 2 (2010) - Indian Point 2 (2016) - Salem 1 (2016)

EPRI/PWROG

10:15 a.m. Break All

10:30 a.m.

Industry Assessments of BFB Inspection Findings - 2012 Westinghouse Technical Bulletin - 2016 Westinghouse NSAL

EPRI/PWROG

11:15 a.m. Charter and Objectives of Industry BFB Focus Group

EPRI/PWROG

12:00 p.m. Next industry steps and on-going related efforts - Upcoming planned outage inspections (2016-2017) - Near-term Focus Group actions (6-12 months) - Longer-term Focus Group and industry actions

EPRI/PWROG

12:30 p.m. NRC staff perspectives, questions, discussion NRC

12:45 p.m. Public Comment and Concluding Remarks All

P R E S S U R I Z E D W A T E R R E A C T O R O W N E R S G R O U P

Global Expertise • One Voice

Baffle Former Bolt Overview of Industry Experience

Heather Malikowski (Exelon), Chair Bryan Wilson (Westinghouse)PWROG Materials Committee

July 19, 2016


Westinghouse NSSS Internals

Control Rod Guide Tube

Outlet Nozzle

Core BarrelThermal Shield

Former Plate

Hold Down Spring

Lower Core Support Plate

Vessel Head

Pressure Vessel

Inlet Nozzle

Upper Support Plate

Lower Core Plate

Bottom-Mounted Instrumentation Column Body

Lower Support Column Body

Upper Core Plate

Baffle Plate

Upper Support Column

2


Baffle-Former Assembly

ExampleBaffle-former

Bolt Locations

Thermal Shield

Core Barrel

Baffle Plate

Former Plate

Source: ML15331A264

3


Baffle-Former Assembly Details

Baffle

Baffle Plate Edge Bolt

Baffle to Former Bolt (Long & Short)

Corner Edge Bracket Baffle to Former Bolt

Core Barrel to Former Bolt

Core BarrelFormer

Source: ML15331A1794


Coolant Flow ConfigurationsUpflowConfiguration

Coolant Flow

Baffle Plate

Former Plate

New Flow Hole

Plug

Coolant Flow

Coolant Flow

Core Barrel

Thermal Neutron Shield

DownflowConfiguration

Source: ML0731903765


Timeline

Note: UT deployed as it became available and qualified for the various sites

DC Cook finds degraded bolts by visual

inspection

First UT baffle-former bolts (BFB) inspections in French PWR CP0 units and first cracks found

Indian Point 2, Salem 1 find

degraded bolts (visual+UT)

Ginna performs first MRP-227 inspectionsFirst degraded

baffle-former bolts found in U.S.

WCAP-13266: BFB Program for the

Westinghouse Owners Group - Plant

Categorization

NRC Information

Notice 98-11 on BFBs MRP publishes

assessment of French BFB OE (MRP-03)

MRP publishes Reactor Internals

Inspection Guidelines (MRP-

227)

NRC reviews & approves MRP-227

Westinghouse Technical Bulletin TB-12-5, related to the DC Cook OE

Operating Experience

Guidance

6


EDF Experience 1989-Present• Baffle bolt failures reported 1989 – Present

– Limited to CP0 design• 3-loop (converted to upflow)• Significant plant-to-plant variability• CPY design (<5 indications over life of plant)

7


EDF Response• Safety Case

– LOCA Loads– Acceptable loads on remaining bolts– Acceptable loads on fuel assembly grids– Minimal number of “healthy bolts” ~30% with limits on distribution

• Periodic bolt replacement– Failed original bolts– Periodic replacements included previously replaced bolts– Sufficient number of “healthy bolts” to push next inspection to 10

years (based on projection model)

8


Joint Owners Baffle Bolt Program (15-22 EFPY)

• Sponsored Inspections of four plants– Point Beach Unit 2: 2-loop, Upflow (converted) , Type 347SS

• 8% UT Indications• Partial replacement program

– Farley Unit 1: 3-loop, Upflow (converted), Type 316SS• No UT Indications• Proactive replacement of minimum pattern

– Ginna: 2-loop, Downflow, Type 347SS• 9% UT Indications (Of these, 14 were sent for metallurgical examination. Results showed no

indications of cracking, so this 9% likely contains a number of false calls)• Partial replacement program

– Farley Unit 2: 3-loop, Converted Upflow (downflow at time of inspection), Type 316SS• No UT Indications• Proactive replacement of minimum pattern9


WEC MRP-227 Baffle-Former Bolt Inspections (25-35 EFPY)

• Point Beach Unit 1: 2-Loop, Upflow (converted), Type 347SS – 1st Inspection: No UT Indications

• Point Beach Unit 2: 2-Loop, Upflow (converted), Type 347SS – 2nd Inspection: 2% Additional UT Indications

• Ginna: 2-Loop, Downflow, Type 347SS – 2nd Inspection (partial inspection of 123 original bolts and 56 replacement bolts):

1 Additional UT Indications (Partial Replacement – 25 bolts)• Prairie Island Unit 1: 2-Loop, Downflow, Type 347SS

– 1st Inspection: 6% UT Indications• Prairie Island Unit 2: 2-Loop, Downflow, Type 347SS

– 1st Inspection: 10% UT Indications

10


WEC MRP-227 Baffle-Former Bolt Inspections (25-35 EFPY)

• Surry Unit 1: 3-Loop, Downflow, Type 347SS– 1st Inspection: <1% UT Indications

• Surry Unit 2: 3-Loop, Downflow, Type 347SS– 1st Inspection: <1% UT Indications

• Robinson: 3-Loop, Downflow, Type 347SS– 1st Inspection: <1% UT Indications

• Turkey Point Unit 3: 3-Loop, Downflow, Type 347SS– 1st Inspection: No UT Indications in 305 of 1088 bolts inspected

• Indian Point Unit 2: 4-Loop, Downflow, Type 347SS– Inspection results addressed in detail on a later slide

11


International Plants• Doel 1: 2-Loop Downflow, Type 316SS

– 1st Inspection: 2% UT Indications• Doel 2: 2-Loop Downflow, Type 316SS

– 1st Inspection: <1% UT Indications• Krsko: 2-Loop, Downflow (prior to inspection), Type 316SS

– 1st Inspection: <1% UT Indications• Tihange 1: 3-Loop, Upflow (converted), Type 316SS

– 960 of 1088 bolts inspected in each of the following inspections– 1st Inspection: 4% UT Indications– 2nd Inspection: 3% UT Indications– 3rd Inspection: No confirmed UT Indications (5 bolts either not inspectable or not interpretable)

12


B&W-Designed RV Internals Baffle-to-Former Bolt Examinations (19-32 EFPY) [1 of 2]

• Four baffle-to-former bolt (BFB) UT examinations completed at B&W-designed units to date– Oconee Unit 1

• No relevant UT indications• Four BFBs uninspectable due to large welds on locking bars

– Oconee Unit 2• No relevant UT indications• One BFB uninspectable due to UT probe not seating properly

– Oconee Unit 3• One BFB identified with crack-like indications• One BFB uninspectable due to UT probe not seating properly

– Crystal River Unit 3• No relevant UT indications• UT performed due to visual indication from baffle-to-baffle bolts

13


B&W-Designed RV Internals Baffle-to-Former Bolt Examinations (19-32 EFPY) [2 of 2]

• All BFBs Type 304 solution annealed stainless steel• B&W design is an upflow configuration• One BFB out of 3,450 BFBs UT examined identified with

crack-like indications• VT examination of all 3,456 BFBs identified no relevant

indications

14


Observations from Broader OE• With the exception of the OE at Cook Unit 2, Indian Point Unit

2, and Salem Unit 1 (discussed later in the presentation), the following observations can be made:– Bolts with UT indications tend to be randomly distributed– Distributions are consistent with expectations of IASCC failures– Quantity and distribution of bolts with indications bounded by

historical generic safety assessment (WCAP-15328)– Industry response to replacement of bolts with indications has

been positive

15


Experience with Clustered Bolt Failures

• DC Cook Unit 2 (2010 / 22 EFPY) (4-Loop Downflow Configuration)– Fuel failure in peripheral assembly attributed to wear against broken bolt head– Bolt heads and lock bars found on lower core plate– Visual inspections revealed 18 degraded bolts on single plate

• Additional bolts removed from plate with visual indications to define extent of localized degradation (approx. 40 bolts in single patch)

• Additional test bolts removed from symmetrical locations to evaluate potential for degradation on other plates (all of these test bolts were found to be intact)

– No UT inspections performed in 2010 (at that time UT was not qualified or optimized for the Cook 2 bolt design)

– Degraded and test bolts replaced– Westinghouse issued Technical Bulletin TB-12-5– 100% Visual inspection conducted in 2012 with no additional indications

16


Experience with Clustered Bolt Failures• Indian Point Unit 2 (2016 / 31 EFPY) (4-Loop Downflow Configuration)

– Degraded bolts and lock bars noted in visual exams performed prior to MRP-227 100% UT exams that were planned to occur during this outage

– Markings on periphery of neighboring fuel assembly identified (no fuel failure).– Inspections identified 227 with visual degradation or UT indications

• Includes 14 that were not inspectable– UT indications were clustered

• Spanned various quadrants• Multiple groups of 10+ adjacent failures• At least one cluster of 50+ adjacent failures

– Observed failure pattern exceeds WCAP-17096 acceptance criteria– Site-specific response:

• Performed Acceptable Bolting Pattern Analysis (ABPA)• Performed Replacement Bolting Pattern Analysis• Performed engineering evaluations supporting Unit 3 Extent of Condition Evaluation• Performed engineering evaluations supporting Unit 2 Assessment of Potential Safety Impacts• Performed baffle-former bolt removal and replacement • Quarantined select bolts for potential future testing

17


Experience with Clustered Bolt Failures• Salem Unit 1 (2016 / 28 EFPY) (4-Loop Downflow Configuration)

– Conduct visual exams every other refueling outage in response to DC Cook Unit 2 OE and TB-12-5; MRP-227 exams were not planned until 2017

– Degraded bolts and lock bars noted in visual exams followed by performance of UT exams– Loose or protruding bolt heads resulted in fuel fretting and a leaker at one fuel assembly– Inspections identified 182 with visual degradation or UT indications

• Includes 18 that were not inspectable– UT indications were clustered

• Concentrated to a few adjacent octants• Multiple groups of 10+ adjacent failures• At least one cluster of 50+ adjacent failures

– Observed failure pattern exceeds WCAP-17096 acceptance criteria– Site-specific response:

• Performed Acceptable Bolting Pattern Analysis (ABPA)• Performed Replacement Bolting Pattern Analysis• Performed engineering evaluations supporting Unit 1 Justification for Past Operation• Performed engineering evaluations supporting Unit 2 Extent of Condition Evaluation• Performed baffle-former bolt removal and replacement• Quarantined select bolts for potential future testing

18


Conclusions from Recent OE• These three plants share a common plant design configuration (4-loop

downflow) and bolt design• Bolts with visual or UT indications tend to be clustered• Distributions seem to indicate the presence of a mechanism causing

adjacent bolts to become more susceptible to failure• Most likely cause is redistribution of a sustained stress resulting in

increased IASCC susceptibility• Quantity and distribution of bolts with indications warranted the

creation of an industry focus group and the issuing of Westinghouse NSAL-16-1 and AREVA CSB 16-02

19

Global Expertise • One Voicewww.pwrog.com

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AREVABaffle-to-Former Bolt Customer Service Bulletin No. 16-02

S. Fyfitch, AREVA Inc.

B&W-Design Baffle-Former Assembly

Baffle Plate

Former Plate

Core Barrel

Thermal Shield

Core Ba

Baffle-to-Baffle Bolt Locations

Core Barrel-to-Former Bolt and Baffle-to-Former Bolt Locations

Baffle-to-Former Bolt Locations (1/8th core)

B&W-Designed RV Internals Operating Experience

Four baffle-to-former bolt (BFB) UT examinations completed at B&W-designed units to date

One BFB out of 3,450 BFBs UT examined identified with crack-like indicationsVT examinations of all 3,456 BFBs identified no relevant indications

Concluded there is very high probability this was a random failure and not an indication of active degradation mechanism having initiated

AREVA Customer Service Bulletin No. 16-02 (1/4)

Customer Service Bulletin released July 14, 2016Subject:

Preliminary evaluation of relevance of recent BFB degradation at Westinghouse-designed 4-loop units to B&W-designed 177-FA unitsPreliminary evaluation relative to risk to safety and operability of B&W-designed 177-FA units


Conclusions:BFBs and baffle-to-baffle bolts (BBBs), regardless of RV internals design, are potentially susceptible to irradiation-assisted stress corrosion cracking (IASCC)

Two primary factors affect IASCC-Accumulated fluence-Stress

Several key stress drivers for IASCC-Relatively high stress due to reactor coolant design configuration (downflow vs. upflow)

-Bolting installation and design characteristics- Bolt fabrication process- Bolt length- Bolt head-to-shank design- Initial torque levels


Conclusions (cont.):Very unlikely that failure rate leading to unacceptable BFB configuration could occur before performing next MRP-227 examinations (initial or subsequent) at any B&W-designed 177-FA unitRisk of observing OE similar to that seen at Westinghouse-designed units to date is low


These recommendations are provided until further evaluation and assessment of current issue is completed through PWROG and industry BFB Focus Group:

It is recommended that B&W-designed 177-FA units continue to follow BFB and BBB (and BFB and BBB locking devices/locking weld) inspection guidelines of MRP-227 and implement any future MRP guidance changesIt is also recommended that B&W-designed 177-FA units maintain increased awareness of telltale signs of BFB and BBB degradation through continuation of existing activities:

Evaluating reactor coolant radioactivity levels during fuel cyclePerforming loose parts monitoring and foreign object search and removal (FOSAR) examinations as part of normal refueling activitiesPerforming visual examinations of peripheral fuel assemblies currently identified for assessment of fuel performance

Additional details are provided in Customer Service Bulletin

QUESTIONS

© 2016 Electric Power Research Institute, Inc. All rights reserved.

Tim WellsBFB FG Chairman

Brian BurgosBFB FG EPRI Project Lead

Charter and Objectives

7/19/16

Industry Baffle-Former Bolt Focus Group

NRC Update

2© 2016 Electric Power Research Institute, Inc. All rights reserved.

Industry Plans

The Industry Baffle to Former Bolt (BFB) Focus Group was formed to support an integrated approach among industry organizations to address recent operating experience– AREVA– EPRI– PWROG– Utility Staff– Westinghouse– Others

Focus Area Lead Organization

#1 – /Extent of Condition, Interim Guidance, Technical Interfacing with the NRC

MRP

#2 – Plant/Fleet Operating ExperienceAssessment PWROG

#3 – Repair/Replacement PWROG

#4 – Inspection/NDE MRP

#5 – Irradiated Testing Support MRP

#6 – Aging Management Assessment MRP

Six focus areas with key actions defined


Industry BFB FG Charter

The purpose of the BFB Focus Group is to coordinate industry activities relative to – understanding issues associated with recent baffle former bolts

operating experiences to prevent unnecessary duplication of time and effort

– to coordinate an agreed upon industry approach to resolving issues.

It will act to coordinate industry activities to resolve outstanding issues relative to the potential degradation of baffle former bolts and its impact to plant operations Vendors, MRP, PWROG and utility staff will work together to define a unified approach and will give regular updates to the Joint MRP/PWROG Reactor Vessel Internals Planning Team



The Focus Group is NOT going to involve itself in other issues related to reactor internal components directly – The focus will be only dealing with issues related to baffle former bolts – There may be some actions taken by the team that also facilitate a

broader understanding of IASCC mechanisms which will be beneficial to reactor internals as a whole, but this will be a serendipity of the results obtained from activities coordinated by the focus group

Primary members of the BFB Focus Group will consist of EPRI staff, PWROG, NSSS Vendor staffs, and utility personnel – It is desired to have a well-balanced focus group that can provide

technical areas of expertise in irradiated materials degradation, structural design probabilistic fracture mechanics, and licensing



BFB Focus Group Chairman: The BFB Focus Group will be headed by a Chairman appointed by the Joint PWROG and MRP RV Internals Planning Team leadership– Represent the Industry BFB Focus Group for reporting out activities to

key stakeholders– Act as the industry representative for interactions with the regulator

Project Lead: An EPRI staff member will be appointed as project lead to assist the Chairman in tracking and coordinating the activities of the Focus Group and the implementation of the Charter guidelines described here within– Coordinate all tele-conference and face to face meetings– Implement the Communication Plan

Primary Member: It is expected that primary members will participate in all calls and meetings to the best of their ability and to participate in various focus group activities at a high level



Communication to BFB Focus Group members will be through a combination of emails, tele-conferences and face to face meetings – A weekly email will be sent out summarizing team activities

accomplished during the week along with upcoming short term activities

– Email updates will also be distributed to members of the Joint PWROG/MRP Reactor Vessel Internals Planning Team to keep them abreast of this specific issue and actions being taken by this team

– Updates will be given to the MRP Assessment/IC TAC and the PWROG MSC (that govern the RV Internals Planning Team’s work) at their respective meetings held throughout the year

– Monthly updates will be provided to the PMMP/MAPC EOC Updates will be given to the CNOs upon request


Industry BFB Focus Area Objectives

Cause and Extent of Condition, Interim Guidance (Focus Area #1)– Develop BFB OE database and verify data– Evaluate/trend BFB OE– Develop Interim Guidance– Technical interactions with the NRC

Plant and Fleet Operating Experience Assessment (Focus Area #2)– Westinghouse to complete the 10CFR21 evaluation– Westinghouse to complete an NSAL; AREVA to produce a similar

document for B&W plants (Customer Service Bulletin)

Repair and Replacement (Focus Area #3)– Work with vendors to develop a contingency plan for tooling and bolt

inventory for the upcoming outage seasons (Fall 2016 / Spring 2017)


Industry BFB Focus Area Objectives

Inspection / NDE (Focus Area #4)– Review bolt inspection protocols to see if lessons learned suggest

modifications– Understand UT Probability of Detection as related to UT-acceptable bolts

Irradiated Testing Support (Focus Area #5)– Establish an integrated testing plan to build upon the Indian Point 2 root

cause evaluation/analysis and further advance IASCC susceptibility knowledge

– Evaluate the need to include Salem 1 and Ginna BFBs into the integrated testing program

Aging Management Assessment (Focus Area #6)– Review previous aging management assessments and compare to

current OE experiences– Evaluate prediction models like the Weibull distribution in MRP-03 (which

is based on French data)– Potential revisions to MRP-227


Industry Communications

Weekly updates to Industry BFB FG membersSupported presentation to NSIAC on 5/23/16– Westinghouse Technical Bulletin TB-12-5 remains valid

Provided Industry Alert Letter from the PMMP Chairman on 6/1/16– We fully expect that NEI 03-08 Interim Guidance will require the 4-

loop plants identified in the Westinghouse TB-12-5 bulletin to perform UT inspections of all the BFBs or replace an acceptable pattern of bolts at their next outage.

– Consideration should also be given to proceeding with procurement of replacement bolts prior to issuance of interim guidance due to potentially long manufacturing lead times.


Together…Shaping the Future of Electricity


Backup slides


Industry BFB FG Charter – Org Chart

Industry BFB FG Team Leads

Tim WellsIndustry BFB Focus

Group Chairman

Brian BurgosIndustry BFB Focus Group Project Lead

Overall Program Updates

Joint MRP / PWROG Reactor Internals

Planning TeamPMMP / MAPC EOC

US NRCTechnical Issues

PWROG MSCMRP TAC & IC

MRP PWROG Vendors Utility FG Members

MRP Assessment TAC

Brian Burgos Kyle Amberge

M&T TACJean Smith

MSCJim Molkenthin

WestinghousePatty Paesano

AREVATammy Natour

3rd Party Vendors(SIA, DEI, etc)

Aging Management Assessment

Irradiated Testing Support

Repair / Replacement

Plant / Fleet Operability Experience Assessment

Provide Guidance and Oversight

EOC / Interim Guidance /

Regulatory Tech. Interfacing

Inspection TAC Jack Spanner

Inspection / NDE

US NRCLicensing

Issues


Organizational Layout


Industry BFB FG Charter - Participants

Focus Area #1Cause/Extent of Condition / Interim Guidance

Focus Area #2Plant and Fleet Operating Experience Assessment

Focus Area #3Repair and Replacement

Focus Area #4Inspection / NDE

Focus Area #5Irradiated Testing Support

Focus Area #6Aging Management Assessment

Leads Tim WellsBrian Burgos

Heather MalikowskiBryan Wilson

William SimsGreg GontisWade Markham

Rachel DossJack Spanner

Chris KoehlerJean Smith

Glenn GardnerKyle Amberge

Additional Vendor / EPRI Support

Bryan WilsonSteve FyfitchMark Richter (NEI)Bruce Montgomery (NEI)Anne DemmaKyle AmbergeTim GriesbachChris LohseJim Molkenthin

Kyle AmbergeGreg TroyerJim AndrachekJim Molkenthin

Jim MolkenthinKyle Amberge

Pat MinogueDavid CisloAnne Demma

Mike BurkeSteve FyfitchAnne Demma

Josh McKinleyGreg TroyerAnne DemmaRandy Lott

Utility Participation

Nelson Azevedo Nelson Azevedo Heather Malikowski William Sims Nelson Azevedo William Sims

Tom Malota Greg Kammerdeiner Steve Petro Greg

Kammerdeiner Tom Malota Steve Petro

Glenn Gardner Tom Malota Eric Brackeen Kevin Hacker Jim Cirilli Mo Dingler

Jim Cirilli Glenn Gardner Dave Mora Ed Maloney / Kris Garg

Heather Malikowski

Rachel Doss Tim Wells Tim WellsMo Dingler Rebecca SiegristEd MaloneyHeatherMalikowskiGay HaliburtonEric Brackeen


Upcoming Planned Refueling Outages

Upcoming Refueling Outages will help to inform us further on fleet trendsAdditional OE from upcoming domestic refueling outages will add to our knowledge base– Fall 2016: 3 planned MRP-227 UT inspections (2 of 3 are Tier 1a

plants)– Spring 2017: 3 planned MRP-227 UT inspections (all Tier 1a plants)

and 1 VT-3 inspection (Tier 1b plant)– Fall 2017: 3 planned MRP-227 UT inspections (1 of 3 is a Tier 1a

plant)– Spring 2018: 1 planned UT re-inspection (Tier 1a plant)

Additional International OE is expectedOut year planning will be important for inspection tooling preparation and for potential use of replacement equipment.


Extent of Condition / Interim Guidance / NRC Interfacing (Focus Area #1)

Primary objectives in the short term:– Developed an OE database and analyze for trends to identify potential

relationships between known failures and plant design/operating conditions

This will be a significant input in developing Interim Guidance– Issue initial NEI 03-08 Interim Guidance to MRP-227/228 in the Fall 2016

timeframePotential update to Interim Guidance in 2017 based on OE from Fall 2016 and Spring 2017 refueling outages and other focus group activities

– Confirm refueling outage schedules for the next 2 years to feed into Focus Area #3 (Repair / Replacement needs)

This is needed to develop planning for both UT and replacement tooling and inventory assessment of typical BFB designs

– Support interfacing between regulatory authorities and industry groups


Extent of Condition / Interim Guidance / NRC Interfacing (Focus Area #1)

Many combinations of data are being assessed– Are there plant parameters that indicate susceptibility?– Are there combinations of parameters that indicate trends?– Are there design parameters that indicate trends?

Trending of data continues and will support the development of Interim GuidanceDevelopment of the Industry BFB OE database is ongoing and will provide a means to capture and assess results of future inspections


Plant/Fleet Operating Experience Assessment (Focus Area #2)

Primary focus is on the development of the Westinghouse NSAL and the AREVA Customer Service Bulletin– NSAL issued 7/5/16– AREVA CSB issued 7/14/16

Assisted in the development of an operating experience assessmentWill continue to review OE


Repair / Replacement (Focus Area #3)

Recent OE at IP2 and Salem 1 identified issues related to replacement tooling availability– Delays in BFB replacement tooling were experienced due to

limited availability of equipment Key input for this focus area is the development of the outage schedule for the next 2 years along with scheduled inspections (volumetric or visual)Fall 2016 refueling outage support:– Contingency plan recommendations are being developed to

assist plants


Repair / Replacement (Focus Area #3)

Ongoing evaluations are underway for vendor capital and/or PWROG tooling investment– What is the appropriate amount of tooling needed– How do the outages overlap in Spring 2017– Are modifications or changes needed to the existing equipment for

production or reliability

Material availability assessment completed – Both vendors have bolting material to fabricate roughly 1,500 BFBs– Items under consideration

Are increased machining rates required to potential provide sufficient bolts in a timely manner if requiredIs a common bolt design possible to allow for faster machining rates


Inspection / NDE (Focus Area #4)

Current methods are identifying defectsReview bolting UT results for lessons learned relevant to the protocol Provide input to Focus Area #5 on recommended NDE examinations of bolts received from IP2 and Salem 1– Recommended PT prior to Destructive Examination

Evaluate the ability to correlate UT signals with measured crack size from destructive examination– May be impractical with multiple bolt designs and varying

vendor UT techniques– Internal hex head bolts and locking devices are

particularly difficult to UT


Irradiated Testing Support (Focus Area #5)

Short-Term Testing (2016)• Work to support Indian Point and Salem root

cause and operability analyses

Intermediate-Term Testing (2016)• Testing with fleet-wide applicability

resulting from the OE

Long-Term Testing (2017+)• Evaluation of IASCC susceptibility of BFB

materials with respect to dose and time

• IP2 has shipped 32 bolts to the Westinghouse Hot Cell Facility (received 6/29/16)• Shipment of Salem bolts (6+) to follow• Ginna bolts (6) to be shipped in August 2016



Activity Notes

Bolt Receiving & Transportation into Hot Cell 32 bolts (IP2), 6 bolts (S1)

Bolt Fracture Surface Examination• Optical microscopy, SEM• Identify fracture modes (IASCC, fatigue, creep)• Correlate with opposite fracture surface to assess potential

relative motion or rotation

Work supports root cause analyses

Remaining Property Testing• Room temperature pull tests of bolts determined by NDE to

have crackingAlloy Chemistry Confirmation

Radionuclide Analysis (dpa) Can be conducted on same sample as alloy chemistry

Technical Report

Clean-up & Return of Materials to Site All material to be returned to utility after testing

Proposed Short-Term Testing (2016)



Focus Area #5 Action Items:• Develop testing plan by the end of July based on clear test

objectives and outcomes• Prioritize needed information to optimize funding• Coordinate funding sources such as utility, PWROG, MRP,

and DOE


Aging Management Assessment (Focus Area #6)

Focus Area #6 is taking a long term approach toward understanding the mechanisms and adjusting the guidance of MRP-227 as required; for example:–Review previous aging management assessments

and compare to recent OE–What materials/structural models best replicate

observed OE and what do they predict for the futureIdentify any requirements that would modify the interim guidance issued by Focus Area 1


Aging Management Assessment (Focus Area #6)

Recommend any updates for future MRP-227 revisionsEvaluation of repair/replacement modifications– Account for these within MRP-227– Relative effectiveness of options over the long term

Recommend adjustments to WCAP-17096 methodology as appropriate


Near Term Industry BFB FG Actions to be completed

Assessment of Fall 2016 and Spring 2017 outage seasons for developing a contingency plan for tooling and BFB material needsDevelop NEI 03-08 Interim Guidance taking into account trending of BFB OE database and recent OEFinalize integrated irradiated testing plan which will feed into Focus Areas 1, 2, 4, and 6


Together…Shaping the Future of Electricity

U. S. Nuclear Regulatory Commission

NRC Perspectives on Baffle-Former Bolt Degradation

July 19, 2016

1

Recent Operating Experience

• From 2010-2016, MRP-227-A inspections were performed at several Westinghouse 2-loop and 3-loop plants

– 2-loop plants had 5-10% degraded baffle-former bolts

– 3-loop plants had very few degraded baffle-former bolts

• In 2010, one Westinghouse 4-loop plant visually noted a large number of degraded bolts on one baffle plate (not during MRP-227-A inspection)

• In 2016, two Westinghouse 4-loop plants performed MRP-227-A inspections and found more degraded bolts than expected (27% and 22%)

• Plants with significant degradation are Westinghouse 4-loop designs with a “downflow” configuration and Type 347 stainless steel bolts

2

NRC Response to Recent OE

• Reviewed recent industry and vendor guidance on this issue

• Evaluated immediate safety significance of issue through internal processes (LIC-504)

• Regional staff has been alerted to issue and have engaged the licensees at sites with susceptible reactor designs

• Conducting baseline inspections focused on the issue at the two plants with extensive bolt degradation in 2016

3

NRC Inspections

• The NRC staff performed targeted inspections at the two plants with significant degradation.

• Inspection focused on:

– NDE quality and accuracy (VT, UT)

– Corrective actions, including evaluation of operating units

– Adequacy of replacement bolt pattern, including margin for additional failures during next cycle

• Results of the NRC inspections will be documented in publically available inspection reports.

4

Safety Significance

• NRC initial conclusion is that susceptible plants do not need to immediately shut down:

– The consequences of baffle plate detachment during normal operation would be limited to localized fuel damage, detectable by periodic coolant activity monitoring required by the TS

– Only certain events (large LOCA, medium LOCA, or seismic events) have the potential to rapidly detach the baffle plate due to baffle-former bolt degradation

– In such an event, the detachment of a baffle plate is not expected to pose a significant challenge to the ability to shutdown the reactor and cool the core

– Initial assessment is that the frequency of such events does not rise to the level of an “imminent safety concern” and does not require any immediate shutdown

• Many degraded bolts retain significant load-bearing capacity such that they would resist failure during a LOCA or seismic event

• NRC is monitoring inspection plans of susceptible plants.

5

NRC Ongoing Actions

• NRC is gathering information on the root cause analyses and the metallurgical analysis of the bolts as it becomes available

• NRC will monitor EPRI MRP changes to inspection guidelines based on current events.

– NRC will review and issue a safety assessment on interim guidance issued by MRP related to baffle-former bolts

– NRC may also address this issue under the review of MRP-227, Rev. 1.

• NRC is evaluating the need for a generic communication, such as an information notice.

6

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