ML12171A528

Pre-Filed Hearing Exhibit NYS000390, NEI Steam Generator Task Force - Nrc/Industry Update, Feb. 18, 2011)

ML12171A528
Person / Time
Site:	Indian Point
Issue date:	02/18/2011
From:	Nuclear Energy Institute
To:	Atomic Safety and Licensing Board Panel
SECY RAS
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References
RAS 22624, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01
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Text

NEI Steam Generator Task Force NRC/Industry Update February 18, 2011 NYS000390 Submitted: June 19, 2012

Agenda 8:30 am Introductions - NRC Opening Remarks - NRC and Industry NEI Steam Generator Task Force Update - Industry

1. NEI 97-06 Revision Status

2. TSTF-510 Update

3. EDF Divider Plate Cracking Update 4

License Renewal Issues 2

4. License Renewal Issues

5. Pre-Service Inspection Code Change

6. Auto-Analysis Workshop Summary

7. U-Bend Axial Outside Diameter Stress Corrosion Cracking Inspection Technique Peer Review

8. Upcoming Changes to Industry Documents

9. Steam Generator Operating Experience 10.Implementation of Noise Monitoring Techniques 11:00 am Address Public Questions/Comments 11:30 pm Lunch 1:00 pm NEI Steam Generator Task Force Update (continued) - Industry Agenda (Continued) 3

11. Follow-up on Previous Meetings

12. Future Topics 3:30 pm NRC feedback on various issues - NRC and Industry 3:45 pm Address Public Questions/Comments - NRC and Industry 4:00 pm Adjourn

NEI 97-06 Revision Status 4

Jim Riley, NEI

NEI 97-06 Revision Status Revision 2 issued in 2005 Need to capture changes in guidance and knowledge SGTF subgroup established 5

SGTF subgroup established Revision 3 distributed to TAG and NRC for review in November Final version of revision 3 completed in January 2011

NEI 97-06 Revision Status Industry comments addressed NRC comments Consistency of shall and should statements

• Changed shoulds to statements of fact Sending Interim Guidance letters and Review Board 6

Interpretations to the NRC

• OK Comments to establish consistency with technical specifications

• Definition of condition monitoring

• Change Expected to Potential tube degradation

NEI 97-06 Revision Status Main changes

- Reduces needed (shall) statements in recognition of EPRI guideline contents

• Uses statements of fact

- Changes Mandatory statements 7

• SG program consistent with 97-06 and EPRI guidelines

• Lists required program elements

• Removes requirement to adopt performance criteria since they are in tech specs

- Updates definitions (consistent with guidelines)

- Corrects inconsistencies with tech specs and EPRI guidelines

NEI 97-06 Revision Status SGTF and SGMP IC endorsed the revision

- Suggested implementation

• September 1, 2011 or

• December 31 2011 if plant has a spring 2011 8

December 31, 2011 if plant has a spring 2011 outage PMMP approval requested

- Expected PMMP approval in March, 2011

TSTF-510 Update 9

Jay Smith, Exelon

TSTF-510 Update Major Milestones Completed

- Rev. 0 of the Traveler & Fee Waiver Request transmitted to NRC on 3/26/09

- Fee Waiver Request Approved on 7/20/09 (ML092010534) 10

- 8 RAIs received via email M. Honcharik (NRC) to B. Mann (TSTF), "TSTF-510 RAIs," February 4, 2010.

• RAI Response and Rev. 1 submittal to NRC June 2010

- 3 comments received at SGTF Mtg August 12, 2010

• Response and Rev. 2 submittal to NRC October 11, 2010

TSTF-510 Update Remaining Milestones TSTF-510 Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection Milestone Action Original Target Date Current Target Date Responsible Group Comments/Status Submit Rev. 0 TSTF Traveler to NRC 1/1/2009 3/26/2009 TSTF/NEI SGTF Complete Receive NRC Acceptance & Schedule Letter 3/1/2009 12/31/2009 TSTF /NEI SGTF Not Sent Receive Rev. 0 RAIs (email used) 6/1/2009 2/4/2010 TSTF /NEI SGTF Complete Respond to Rev. 0 RAIs 9/1/2009 6/15/2010 TSTF /NEI SGTF Complete Submit Rev 1 TSTF Traveler to NRC 1/1/2010 6/17/2010 TSTF /NEI SGTF Complete 11 Submit Rev. 1 TSTF Traveler to NRC 1/1/2010 6/17/2010 TSTF /NEI SGTF Complete Receive Rev. 1 RAIs (SGTF Mtg)

N/A 8/12/2010 TSTF /NEI SGTF Complete Respond to Rev. 1 RAIs N/A 9/15/2010 TSTF /NEI SGTF Complete Submit Rev. 2 TSTF Traveler to NRC N/A 9/22/2010 TSTF /NEI SGTF Complete Receive Notice for Comment 12/1/2009 4/15/2011*

TSTF /NEI SGTF Current Estimate Respond to Notice for Comment 1/1/2010 5/15/2011*

TSTF /NEI SGTF Current Estimate NRC Publish Notice of Availability 4/1/2010 8/31/2011*

NRC Current Estimate

• Change since previous SGTF meeting

NRC Feedback on TSTF-510 12

EdF Divider Plate Cracking Update 13 Update Helen Cothron, EPRI

EdF Divider Plate Cracking Update

Only 900 MW plants have experienced divider plate cracking

- All have 34mm (1.33) divider plates

All 900 MW units have been inspected at least one time

- 4 have had consecutive inspections

- First three divider plate inspections were conducted using PT for detection and non-qualified UT for sizing

• No change in number of cracks few variations in depth 14

• No change in number of cracks, few variations in depth

(~1mm of growth), but this could be NDE uncertainty

- 2010 was the first use of qualified UT by Westinghouse

• With qualified techniques, cracks that were sized as 7 to 8mm in depth were sized as <2mm deep

- All indications are in or close to the heat affected zone (HAZ) of the tubesheet to stub runner weld and in or close to the HAZ of the stub runner to divider plate weld

- No cracking in the welds

- Only small (depth - 2 microns) cracks in stub runner itself.

EdF Divider Plate Cracking Update

EdF removed 2 divider plate samples from retired SGs at Chinon B1 in 2008

- NDE prior to and following removal have same results

• UT detection by Westinghouse was the same but the indicated depth was smaller at <2mm (1.8 mm after destructive measurement)

Stub runner discovered to be bowed in center 15

- Stub runner discovered to be bowed in center

- HAZ had carbide dissolution in about 2mm thick layer

- EdF believes the deformation could have been caused by the first hydrostatic pressure test performed at 1.33 times design pressure (22.8 MPa or 3300 psi).

• U.S. ASME Section III hydros performed at 1.25 times design Pressure (~3100 psi)

EdF Divider Plate Cracking Update 16 Triiple Point

• DE on 3 SG divider plates

• Fabrication defects

• No sec Tubesheet Divider Plate

EdF Divider Plate Cracking Update 17

• Deeper cracks are on the top and bottom of the stub runner

• Cracks are intergranular

• Propagation is parallel to the weld

• No cracks on the divider plate and no cracks on the weld

• No cracks at the triple point or near the tubesheet

EdF Divider Plate Cracking Update

Root Cause

- SCC observed in hot leg on SGs with operating time >120,000 hrs (13.7 yrs)

- SCC observed in SG Divider Plate components where material was supplied by one vendor

• Material had high carbide level (>0.5%) and high temperature final heat treatment promoting intra carbides 18

- SCC observed in SGs with 34mm (1.33) thick divider plates from 3 loop plants, containing stub runners with low mechanical properties and divider plates with high mechanical properties.

• Important difference in yield strength in stub runner and divider plate. When stub runner has low mechanical properties than divider plate, then it deforms and becomes susceptible to cracking.

EdF Divider Plate Cracking Update Mechanical tests performed on materials with representative mechanical properties shows:

Crack depth propagation in the center of 19

- Crack depth propagation in the center of the stub runner is from 0.07 mm/cycle (8,000 hrs) to 0.2 mm/cycle.

- Crack depth propagation in the HAZ is 0.17 mm to 0.21 mm/cycle.

EdF Divider Plate Cracking Update Comparison of EdF Affected Plants to US Plants Apparent Causal Factor of DP Component SCC EdF Plants with Divider Plate SCC U. S. Plants Divider Plate Thickness (Nominal) 1.33 Model 51: 1.31 Model 44F: 1.50 Models 51F/51M/

54F/D3*/D5/F: 2.0 Primary Hydro Test 1 33 x P 1 25 x P 20 Primary Hydro Test Pressure 1.33 x Pdesign 3300 psi 1.25 x Pdesign Typically ~3100 psi Stub Runner Low Strength Divider Plate High Strength Yes U.S. DP and stub runners mechanical properties are within A600 material spec limits Plant Load Follow Yes No

• D3 -

Ringhals-3 detected shallow cracking in stub runner in 2005 by PT exam. Not confirmed by UT.

EdF Divider Plate Cracking Update 900 MW SG Inspection Frequency as proposed for approval by the French Regulator

- If SCC defects are detected that are <2mm deep, inspect every 10 years 21

- If SCC defects are detected that are >2mm and

<4mm deep, inspect every 4 years

- If SCC defects are detected that are >=4mm deep, inspect every 2 years

EdF Divider Plate Cracking Update 1300 MW SG Inspection Frequency as proposed for approval by the French Regulator

- Thicker divider plate, 60mm (2.36)

- All but 5 units have been inspected at least one time 22

• 5 units have still to be inspected in order to inspect all heats at least one time

- No SCC identified or expected

- If no SCC, no additional inspections All Alloy 600 divider plates will be inspected at the triple point every 10 years

EdF Divider Plate Cracking Update

Summary

- NDE and DE have provided a good understanding of the local strain history on components affected by SCC

- Divider Plate Components with SCC share the following characteristics:

• SCC only found in 900 MW 3-loop plants with 34 mm (1.33) thick divider plates

• Divider plates supplied by one material vendor and were heat treated at high temperatures that promoted intra carbides and high carbide levels.

23

• Stub runners had low mechanical properties while divider plate had high mechanical properties promoting plate deformation that was not anticipated

• High hydrostatic pressure tests may have promoted divider plate deformation

• SCC always located in most significantly strained areas. SCC not found with components with no significant plastic deformation.

- SCC has not been found in the triple point.

Divider Plate/Cladding Cracking EPRI SGMP Draft Work Scope 24 EPRI SGMP Draft Work Scope for 2011 and 2012 Helen Cothron, EPRI Chris Cassino, Westinghouse

Project Objectives Objective 1: Determine the chromium content in the as-constructed Alloy 82/182 clad tubesheet and Alloy 690 tubing Objective 2: Determine if cracks can 25 j

propagate from the divider plate to other components and affect the integrity of the primary pressure boundary Two year SGMP project

- Funding approved for 2011.

Objective 1: Cracking in Alloy 600 Cladding

Task 1: A literature review of crack growth rate studies Review of the data supporting conclusions Review of outliers and any data pertaining to the directionality of crack propagation 26

Task 2: Obtain small boat samples for chemical analysis of cladding and final as-built tube end welds in typical SGs with Alloy 82 cladding and Alloy 690 tubing Potential sources of these specimens are replacement SG manufacturers.

Objective 2: Divider Plate Cracking

Task 1: Finite element analysis to determine what conditions are necessary for cracks in the divider plate to propagate in any one of the following three paths (1) Initiating in the stub runner to tubesheet connection and propagating to an adjacent tube end weld (2) Initiating in the divider plate or stub runner material 27 (2) Initiating in the divider plate or stub runner material and propagating to the base metal of the channel head (3) Initiating in the divider plate or stub runner material and propagating to the base metal of the tubesheet.

The goal of the study will be to evaluate what is necessary to turn the crack path from the divider plate into the components of the primary pressure boundary.

Objective 2: Divider Plate Cracking

Task 2: If Task 1 concludes that cracks can propagate as proposed, perform a feasibility study for designing and assembling mock-ups for testing of the possible crack propagation modes 28 Results could be used to estimate crack growth rates and guide potential inspection methodology The feasibility study will determine if appropriate testing materials are available and if it would be practical to perform such tests

License Renewal Issues 29 Helen Cothron, EPRI Jay Smith, Exelon

License Renewal Issues Divider Plate Cracking Due to NRC License Renewal staff RAI, plants are committing to divider plate inspections once they have entered the extended period of operation 30 extended period of operation.

Utilities will use SGMP project results to validate or change their commitments.

License Renewal Issues Tube Sheet Cladding Cracking Recent RAI on tubesheet cladding cracking postulates that cracking may initiate in the Alloy 600 cladding material and then propagate to the 600/690 weld at the tube end 31 Utilities are committing to inspection of this area after entering the extended period of operation Utilities will use SGMP project results to validate or change their commitments.

License Renewal Issues Primary Side Fouling Update

During the August 12, 2010 SGTF meeting, it was discussed that a number of units have identified primary side fouling as a SG aging effect in their license renewal applications.

Given the lack of information on the occurrence of primary side fouling in domestic SGs, the NRC Staff asked the Ind str to pro ide additional information on primar side 32 Industry to provide additional information on primary side fouling.

The industry agreed to discuss this issue with licensees that included primary side fouling in their license renewal application to determine the reason for its inclusion.

- The NRC presented to the SGTF a list of 9 plants that included primary side fouling in their license renewal requests.

License Renewal Issues Primary Side Fouling Update

SG primary side fouling was discussed at recent License Renewal Task Force (LRTF) and Implementation Working Group meetings.

- After discussions, it was concluded that SG primary side fouling was not an aging mechanism and should not be included in future applications.

- Possible reasons for inclusion included using generic heat exchanger GALL template for SGs and/or mis-understanding of the 33 g

p g

GALL requirement.

==

Conclusion:==

SGTF does not consider SG primary side fouling an aging mechanism.

- The identified plants that included primary side fouling were contacted and they understand that primary side fouling is not considered an aging mechanism.

• Changes to LRA is a plant specific decision.

Recommended Actions

- SGTF to communicate conclusion to LRTF

- NRR to communicate conclusion to NRC License Renewal Branch

Pre-Service Inspection Code Guidance 34 Viki Armentrout, Dominion Jay Smith, Exelon

Pre-Service Inspection Code Guidance NRC Comment regarding Pre-service Examination of SG tubing:

- IWB-2200(c) of Section XI of the ASME Code indicates that steam generator tube examination 35 shall be governed by the plant Technical Specification. The technical specifications do not address pre-service inspections. Discuss with the industry a path forward to address this issue (e.g., incorporating pre-service inspections into TSTF-510, modifying the ASME Code).

Pre-Service Inspection Code Guidance

Action sent out for review and was presented to WGISC in February 2010

- NRC Working Group attendee indicated that the revised wording would not be endorsed by NRC.

• Per NRC, reference to steam generator preservice inspections should be removed from IWB-2200(c) and Table IWB-2500-1 should be modified.

- ASME item BC 10-129 already in place to modify the steam 36

- ASME item BC 10-129 already in place to modify the steam generator inspection requirements.

- Item was not moved for vote based on need to resolve this NRC comment.

- The best likely date to achieve NRC approval in 10CFR50 will be 2015.

• Next ASME Code Revision 2013

Recommend to close action to ASME tracking item BC 10-129

Auto-Analysis Workshop Summary 37 Steve Swilley, EPRI

Auto-Analysis Workshop Summary Charlotte, NC, February 9th and 10th, 2011

- The EPRI Steam Generator Management Program invites you to attend a workshop in Charlotte, NC at EPRI on February 9th and 10th, 2011. The work shop will focus on the use of automated analysis tools for 38 inspection of steam generator tubing. Although automated analysis tools have been used in the industry since the 1980s, there have been many significant advances in the software technology. This workshop will include utility, vendor, and regulatory updates on existing technology, current practice, field experience, and future directions.

Auto-Analysis Workshop Summary 39 EPRI Steam Generator Automated Analysis Workshop Charlotte. NC Building 1 Room 402 Wtdntsday Ftbmary 9, 2011 Steve ~

Westinghouse Electric Co.; Doug HansenAPS N. ~.M. ~ &K. ~ Mitsubishi Heavy Industries, Ltd Kobe Shipyard and

Auto-Analysis Workshop Summary 40 8:00AM EPRI Steam Generator Automated Analysis Workshop Charlotte. NC Tluu*sday February 10, 2011 Continental Breakfast Session5-Panel Di~cu~sion 8:30AM Opening Remarks and Follow-up from previous day Steve Swilley, EP RI 8:45AM Panel Discussion Various representatives AREVA Westinghouse Zetec Industry NRC MHI 10:00 AM Break 10:30 AM Panel Discussion Continued 11:00 AM Compile discussion points for industry action 11:45AM Lunch Session6-Teclmology Demonsn-ations 1:00PM Functional demonstrations of vendor software Zetec, AREVA, MHI, Michigan State, and Westinghouse applications for automated analysis 5:00PM End of Workshop

Auto-Analysis Workshop Summary 64 Attendees

- 25 Vendor

- 16 Utility

- 15 NRC 41

- 2 Research

- 6 EPRI

- 11 were non US (Canada, Spain, Japan, France, Germany, and Croatia)

Auto-Analysis Workshop Summary Industry Perspective NRC Perspective 42

U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer Review 43 Steve Swilley, EPRI

U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer Review ETSSs Peer Reviewed August 2010

- Detection of Axial ODSCC in Low Row U-Bends

- ETSS 10411, Plus Point Coil Includes Phase and Amplitude Sizing 44

- ETSS 10413, X-Probe

• Detection Only

- ETSS 10414, I-Probe

• MIDAS analysis software

- ETSS 10415, I-Probe

• EddynetSuite analysis software Techniques Available for Industry Use

Upcoming Changes to Industry Documents 45 Documents Jim Benson, EPRI

SGMP Industry Document Status and Revision Schedule 46 Report Last lmplementa Interim Review Comments Current Pub tion G ui del ine Title Guidance Date Rev#

Date

~)

s G Integrity 10190 Nov-9/112010 SGMP-2012 Assessment 3

38 09 IG-1 O-Q1 Guidelines SG In-Situ 10149 Aug-3/1412008 Rev 4 in none Pressure Test 3

83 07 6/1412008 progress Guidelines PWRSG 10137 Oct-SGMP-IG-Rev 8 in Ex am in at ion 7

07 9/112008 08-04 progress 06 Guidelines PWRSG Rev 4 in progress.

Primary-to-10082 Dec-7/1712006 none Expected to Secondary 3

19 04 1 011712006 be issued by Leakage Guidelines Dec 2011

SGMP Industry Document Status and Revision Schedule 47

SGMP Administrative Procedures, Revision 3

Revision 3 has been endorsed by the PMMP EC

Published in December 2010

The SGMP IC will be drafting an Implementation Letter

Draft Implementation Letter was intentionally delayed to allow issuance at about the same time as NEI 97-06, Rev 3

On Jan 12th the IC:

48 On Jan 12, the IC:

- Endorsed draft NEI 97-06, Rev 3

- Recommended a utility implementation date of Sept 1, 2011

• Dec 31, 2011 for utilities with a spring 2011 outage

• EPRI implementation will be immediate

The Implementation Letter will be signed by the PMMP EOC Chair prior to issuance

- Letter expected to be issued in Feb 2011

SG Operating Experience 49 Russ Lieder, Nextera Energy Seabrook, LLC

SG Operating Experience Objective of OE presentation and approach for future meetings OE is extensively discussed amongst utilities in non-public meeting 50

Implementation of Noise Monitoring Techniques 51 Techniques Helen Cothron, EPRI

Implementation of Noise Monitoring Techniques

Vendors have the capability to monitor noise

SGMP has worked with the vendors to ensure the output can be easily transferred to available software to recalculate probability of detection if necessary

Lessons learned have been recorded during three pilot projects Alloy 690TT replacement SGs Alloy 600TT original SG

One additional pilot is planned for 2011 52

One additional pilot is planned for 2011 Alloy 600MA SG with multiple degradation mechanisms This experience is necessary prior to developing recommendations

Revision 8 of the PWR Examination Guidelines is underway during 2011/2012 and will consider recommendation/requirements for noise monitoring

Some plants are experimenting with the noise monitoring capabilities and are providing feedback to SGMP

Follow-up on Previous Meetings 53

Future Topics 54

NRC feedback on various issues TSTF-510 AVB Position Verification 55

Address Public Q

ti

/C t

56 Questions/Comments

Adjourn 57