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{{#Wiki_filter:NEI Steam Generator Task Force NRC/Industry Update February 18, 2011 Agenda8:30 am    Introductions -NRCOpening Remarks -NRC and IndustryNEI Steam Generator Task Force Update -Industry 1.NEI 97-06 Revision Status 2.TSTF-510 Update 3.EDF Divider Plate Cracking Update 4LicenseRenewalIssues 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 Techniques11:00 amAddress Public Questions/Comments11:30 pm  Lunch1:00 pm    NEI Steam Generator Task Force Update (continued) -Industry Agenda (Continued) 3 11.Follow-up on Previous Meetings 12.Future Topics3:30 pm    NRC feedback on various issues -NRC and Industry3:45 pm    Address Public Questions/Comments -NRC and Industry4:00 pm    Adjourn NEI 97-06 Revision Status 4Jim Riley, NEI NEI 97-06 Revision StatusRevision 2 issued in 2005Need to capture changes in guidance and knowledgeSGTFsubgroupestablished 5SGTF subgroup establishedRevision 3 distributed to TAG and NRC for review in NovemberFinal version of revision 3 completed in January 2011 NEI 97-06 Revision StatusIndustry comments addressedNRC commentsConsistency of "shall" and should statements
*Changed "shoulds" to statements of factSending  Interim Guidance letters and Review Board 6 Interpretations to the NRC
*OKComments to establish consistency with technical specifications
*Definition of condition monitoring
*Change "Expected" to "Potential" tube degradation NEI 97-06 Revision StatusMain 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 StatusSGTF and SGMP IC endorsed the revision
-Suggested implementation
*September 1, 2011  or
*December312011ifplanthasaspring2011 8 December 31 , 2011 if plant has a spring 2011 outagePMMP approval requested
-Expected PMMP approval in March, 2011 TSTF-510 Update 9Jay Smith, Exelon TSTF-510 UpdateMajor 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 MilestonesTSTF-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 RAI's (email used) 6/1/2009 2/4/2010 TSTF /NEI SGTF Complete Respond to Rev. 0 RAI's 9/1/2009 6/15/2010 TSTF /NEI SGTF Complete SubmitRev1TSTFTravelertoNRC1/1/20106/17/2010TSTF/NEISGTFComplete 11Submit Rev. 1 TSTF Traveler to NRC 1/1/20106/17/2010 TSTF/NEI SGTFCompleteReceive Rev. 1 RAI's (SGTF Mtg) N/A 8/12/2010 TSTF /NEI SGTF Complete Respond to Rev. 1 RAI's 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 UpdateHelen Cothron, EPRI EdF Divider Plate Cracking UpdateOnly 900 MW plants have experienced divider plate cracking
-All have 34mm (1.33") divider platesAll 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
*Nochangeinnumberofcracksfewvariationsindepth 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 UpdateEdF removed 2 divider plate samples from retired SG's 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
)Stubrunnerdiscoveredtobebowedincenter 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 (~3100psi)
EdF Divider Plate Cracking Update 16 Tr i iple Poi n t
* DE on 3 SG div i der plates
* Fabrication defects *No sec Tubeshee t Divide r Plate EdF Divider Plate Cracking Update 17* Deeper cracks are on the top and bottom of the s t ub runner
* Cracks are intergran u lar
* Propagatio n is parallel to the weld
* No cracks on the div i der p l ate and no cracks on the weld
* No cracks a t the trip l e point or n ear the tubesheet EdF Divider Plate Cracking UpdateRoot 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 UpdateMechanical tests performed on materials with representative mechanical properties
shows:Crackdepthpropagationinthecenterof 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 UpdateComparison of EdF Affected Plants to US PlantsApparent Causal Factor of DP Component SCCEdF Plants withDivider Plate SCCU. S. PlantsDivider Plate Thickness (Nominal)1.33"Model 51: 1.31"Model 44F: 1.50" Models 51F/51M/
54F/D3*/D5/F: 2.0"PrimaryHydroTest133xP125xP 20 Primary Hydro Test Pressure 1.33 x Pdesign 3300 psi 1.25 x PdesignTypically ~3100 psiStub Runner Low StrengthDivider Plate High StrengthYesU.S. DP and stub runners mechanical properties are within A600 material spec
limitsPlant Load FollowYesNo* D3 -Ringhals-3 detected shallow cracking in stub    runner in 2005 by PT exam. Not confirmed by UT.
EdF Divider Plate Cracking Update900 MW SG Inspection Frequency as proposed for approval by the French Regulator
-If SCC defects are detect ed that are <2mm deep, inspect every 10 years 21-If SCC defects are detec ted that are >2mm and <4mm deep, inspect every 4 years
-If SCC defects are det ected that are >=4mm deep, inspect every 2 years EdF Divider Plate Cracking Update1300 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 inspectionsAll Alloy 600 divider plates will be inspected at the triple point every 10 years EdF Divider Plate Cracking UpdateSummary-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 EPRISGMPDraftWorkScope 24 EPRI SGMP Draft Work Scope for 2011 and 2012Helen Cothron, EPRIChris Cassino, Westinghouse Project ObjectivesObjective 1:  Determine the chromium content in the as-constructed Alloy 82/182 clad tubesheet and Alloy 690 tubingOb jective 2:  Determine if cracks can 25 jpropagate from the divider plate to other components and affect the integrity of the primary pressure boundaryTwo year SGMP project
-Funding approved for 2011.
Objective 1:  Cracking in Alloy 600 CladdingTask 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 26Task 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 CrackingTask 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)Initiatinginthedividerplateorstubrunnermaterial 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 CrackingTask 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 po ssible 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 29Helen Cothron, EPRIJay Smith, Exelon License Renewal IssuesDivider Plate CrackingDue to NRC License Renewal staff RAI, plants are committing to divider plate inspections once they have entered the extendedperiodofoperation 30 extended period of operation.Utilities will use SGMP project results to validate or change their commitments.
License Renewal IssuesTube Sheet Cladding CrackingRecent 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 31Utilities are committing to inspection of this area after entering the ext ended period of operationUtilities will use SGMP proj ect results to validate or change their commitments.
License Renewal IssuesPrimary Side Fouling UpdateDuring 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 Indstrtoproideadditionalinformationonprimarside 32 Ind u str y to pro v ide additional information on primar y 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 IssuesPrimary Side Fouling UpdateSG 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 exchan ger GALL tem plate for SGs and/or mis-understandin g of the 33 gp 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 34Viki Armentrout, DominionJay Smith, Exelon Pre-Service Inspection Code GuidanceNRC Comment regarding Pre-service Examination of SG tubing:
-IWB-2200(c) of Section XI of the ASME Code indicates that steam generator tube examination 35shall 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 GuidanceAction 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.
-ASMEitemBC10
-129alreadyinplacetomodifythesteam 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 2013Recommend to close action to ASME tracking item BC 10-129 Auto-Analysis Workshop Summary 37Steve Swilley, EPRI Auto-Analysis Workshop SummaryCharlotte, NC,  February 9 th and 10 th, 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 38inspection of steam generator tubing. Although automated analysis tools have been used in the industry since the 1980's, 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 Westinghouse El e ctric Co.; Doug HansenAPS N.
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 8:3 0AM 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 discuss i on points for industry action 11:45AM Lun ch Session6-Teclmology Demonsn-ations 1:00PM Functional demonstrations of vendor software Zetec, AREVA, MHI, Michigan S tate , and Westinghouse applications for automated analysis 5: 00PM End of Workshop Auto-Analysis Workshop Summary64 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 SummaryIndustry PerspectiveNRC Perspective 42 U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer Review 43Steve Swilley, EPRI U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer ReviewETSS's 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 softwareTechniques Available for Industry Use Upcoming Changes to Industry Documents 45 DocumentsJim 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 3Revision 3 has been endorsed by the PMMP ECPublished 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  OnJan12 ththeIC: 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 49Russ Lieder, Nextera Energy Seabrook, LLC SG Operating ExperienceObjective of OE presentation and approach for future meetingsOE is extensively discussed amongst utilities in non-public meeting 50 Implementation of Noise Monitoring Techniques 51 Techniques Helen Cothron, EPRI Implementation of Noise Monitoring TechniquesVendors have the capability to monitor noiseSGMP has worked with the vendors to ensure the output can be easily transferred to available software to recalculate probability of detection if necessaryLessons learned have been recorded during three pilot projects
-Alloy 690TT replacement SGs
-Alloy 600TT original SGOneadditionalpilotisplannedfor2011 52One additional pilot is planned for 2011-Alloy 600MA SG with multiple degradation mechanisms
-This experience is necessary prior to developing recommendationsRevision 8 of the PWR Examination Guidelines is underway during 2011/2012  and will consider recommendation/requirements for noise monitoringSome 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-510AVB Position Verification 55 Address Public Qti/Ct 56 Q ues ti ons/C ommen t s Adjourn 57}}

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Indian Point Pre-Filed Hearing Exhibit NYS000390, NEI Steam Generator Task Force - Nrc/Industry Update, Feb. 18, 2011)
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NEI Steam Generator Task Force NRC/Industry Update February 18, 2011 Agenda8:30 am Introductions -NRCOpening Remarks -NRC and IndustryNEI Steam Generator Task Force Update -Industry 1.NEI 97-06 Revision Status 2.TSTF-510 Update 3.EDF Divider Plate Cracking Update 4LicenseRenewalIssues 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 Techniques11:00 amAddress Public Questions/Comments11:30 pm Lunch1:00 pm NEI Steam Generator Task Force Update (continued) -Industry Agenda (Continued) 3 11.Follow-up on Previous Meetings 12.Future Topics3:30 pm NRC feedback on various issues -NRC and Industry3:45 pm Address Public Questions/Comments -NRC and Industry4:00 pm Adjourn NEI 97-06 Revision Status 4Jim Riley, NEI NEI 97-06 Revision StatusRevision 2 issued in 2005Need to capture changes in guidance and knowledgeSGTFsubgroupestablished 5SGTF subgroup establishedRevision 3 distributed to TAG and NRC for review in NovemberFinal version of revision 3 completed in January 2011 NEI 97-06 Revision StatusIndustry comments addressedNRC commentsConsistency of "shall" and should statements

  • Changed "shoulds" to statements of factSending Interim Guidance letters and Review Board 6 Interpretations to the NRC
  • OKComments to establish consistency with technical specifications
  • Definition of condition monitoring
  • Change "Expected" to "Potential" tube degradation NEI 97-06 Revision StatusMain 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 StatusSGTF and SGMP IC endorsed the revision

-Suggested implementation

  • September 1, 2011 or
  • December312011ifplanthasaspring2011 8 December 31 , 2011 if plant has a spring 2011 outagePMMP approval requested

-Expected PMMP approval in March, 2011 TSTF-510 Update 9Jay Smith, Exelon TSTF-510 UpdateMajor 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 MilestonesTSTF-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 RAI's (email used) 6/1/2009 2/4/2010 TSTF /NEI SGTF Complete Respond to Rev. 0 RAI's 9/1/2009 6/15/2010 TSTF /NEI SGTF Complete SubmitRev1TSTFTravelertoNRC1/1/20106/17/2010TSTF/NEISGTFComplete 11Submit Rev. 1 TSTF Traveler to NRC 1/1/20106/17/2010 TSTF/NEI SGTFCompleteReceive Rev. 1 RAI's (SGTF Mtg) N/A 8/12/2010 TSTF /NEI SGTF Complete Respond to Rev. 1 RAI's 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 UpdateHelen Cothron, EPRI EdF Divider Plate Cracking UpdateOnly 900 MW plants have experienced divider plate cracking

-All have 34mm (1.33") divider platesAll 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

  • Nochangeinnumberofcracksfewvariationsindepth 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 UpdateEdF removed 2 divider plate samples from retired SG's 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

)Stubrunnerdiscoveredtobebowedincenter 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).

EdF Divider Plate Cracking Update 16 Tr i iple Poi n t

  • DE on 3 SG div i der plates
  • Fabrication defects *No sec Tubeshee t Divide r Plate EdF Divider Plate Cracking Update 17* Deeper cracks are on the top and bottom of the s t ub runner
  • Cracks are intergran u lar
  • Propagatio n is parallel to the weld
  • No cracks on the div i der p l ate and no cracks on the weld
  • No cracks a t the trip l e point or n ear the tubesheet EdF Divider Plate Cracking UpdateRoot 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 UpdateMechanical tests performed on materials with representative mechanical properties

shows:Crackdepthpropagationinthecenterof 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 UpdateComparison of EdF Affected Plants to US PlantsApparent Causal Factor of DP Component SCCEdF Plants withDivider Plate SCCU. S. PlantsDivider Plate Thickness (Nominal)1.33"Model 51: 1.31"Model 44F: 1.50" Models 51F/51M/

54F/D3*/D5/F: 2.0"PrimaryHydroTest133xP125xP 20 Primary Hydro Test Pressure 1.33 x Pdesign 3300 psi 1.25 x PdesignTypically ~3100 psiStub Runner Low StrengthDivider Plate High StrengthYesU.S. DP and stub runners mechanical properties are within A600 material spec

limitsPlant Load FollowYesNo* D3 -Ringhals-3 detected shallow cracking in stub runner in 2005 by PT exam. Not confirmed by UT.

EdF Divider Plate Cracking Update900 MW SG Inspection Frequency as proposed for approval by the French Regulator

-If SCC defects are detect ed that are <2mm deep, inspect every 10 years 21-If SCC defects are detec ted that are >2mm and <4mm deep, inspect every 4 years

-If SCC defects are det ected that are >=4mm deep, inspect every 2 years EdF Divider Plate Cracking Update1300 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 inspectionsAll Alloy 600 divider plates will be inspected at the triple point every 10 years EdF Divider Plate Cracking UpdateSummary-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 EPRISGMPDraftWorkScope 24 EPRI SGMP Draft Work Scope for 2011 and 2012Helen Cothron, EPRIChris Cassino, Westinghouse Project ObjectivesObjective 1: Determine the chromium content in the as-constructed Alloy 82/182 clad tubesheet and Alloy 690 tubingOb jective 2: Determine if cracks can 25 jpropagate from the divider plate to other components and affect the integrity of the primary pressure boundaryTwo year SGMP project

-Funding approved for 2011.

Objective 1: Cracking in Alloy 600 CladdingTask 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 26Task 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 CrackingTask 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)Initiatinginthedividerplateorstubrunnermaterial 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 CrackingTask 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 po ssible 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 29Helen Cothron, EPRIJay Smith, Exelon License Renewal IssuesDivider Plate CrackingDue to NRC License Renewal staff RAI, plants are committing to divider plate inspections once they have entered the extendedperiodofoperation 30 extended period of operation.Utilities will use SGMP project results to validate or change their commitments.

License Renewal IssuesTube Sheet Cladding CrackingRecent 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 31Utilities are committing to inspection of this area after entering the ext ended period of operationUtilities will use SGMP proj ect results to validate or change their commitments.

License Renewal IssuesPrimary Side Fouling UpdateDuring 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 Indstrtoproideadditionalinformationonprimarside 32 Ind u str y to pro v ide additional information on primar y 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 IssuesPrimary Side Fouling UpdateSG 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 exchan ger GALL tem plate for SGs and/or mis-understandin g of the 33 gp 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 34Viki Armentrout, DominionJay Smith, Exelon Pre-Service Inspection Code GuidanceNRC Comment regarding Pre-service Examination of SG tubing:

-IWB-2200(c) of Section XI of the ASME Code indicates that steam generator tube examination 35shall 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 GuidanceAction 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.

-ASMEitemBC10

-129alreadyinplacetomodifythesteam 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 2013Recommend to close action to ASME tracking item BC 10-129 Auto-Analysis Workshop Summary 37Steve Swilley, EPRI Auto-Analysis Workshop SummaryCharlotte, NC, February 9 th and 10 th, 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 38inspection of steam generator tubing. Although automated analysis tools have been used in the industry since the 1980's, 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 Westinghouse El e ctric Co.; Doug HansenAPS N.

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 8:3 0AM Opening Remarks and Follow-up from previous day Steve Swilley, EP RI 8:45AM Panel Discussion Various representatives

  • AREVA
  • Zetec
  • Industry
  • NRC
  • MHI 10:00 AM Break 10:30 AM Panel Discussion Continued 11: 00 AM Compile discuss i on points for industry action 11:45AM Lun ch Session6-Teclmology Demonsn-ations 1:00PM Functional demonstrations of vendor software Zetec, AREVA, MHI, Michigan S tate , and Westinghouse applications for automated analysis 5: 00PM End of Workshop Auto-Analysis Workshop Summary64 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 SummaryIndustry PerspectiveNRC Perspective 42 U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer Review 43Steve Swilley, EPRI U-Bend Axial Outer Diameter Stress Corrosion Cracking Inspection Technique Peer ReviewETSS's 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 softwareTechniques Available for Industry Use Upcoming Changes to Industry Documents 45 DocumentsJim 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 3Revision 3 has been endorsed by the PMMP ECPublished 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 OnJan12 ththeIC: 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 49Russ Lieder, Nextera Energy Seabrook, LLC SG Operating ExperienceObjective of OE presentation and approach for future meetingsOE is extensively discussed amongst utilities in non-public meeting 50 Implementation of Noise Monitoring Techniques 51 Techniques Helen Cothron, EPRI Implementation of Noise Monitoring TechniquesVendors have the capability to monitor noiseSGMP has worked with the vendors to ensure the output can be easily transferred to available software to recalculate probability of detection if necessaryLessons learned have been recorded during three pilot projects

-Alloy 690TT replacement SGs

-Alloy 600TT original SGOneadditionalpilotisplannedfor2011 52One additional pilot is planned for 2011-Alloy 600MA SG with multiple degradation mechanisms

-This experience is necessary prior to developing recommendationsRevision 8 of the PWR Examination Guidelines is underway during 2011/2012 and will consider recommendation/requirements for noise monitoringSome 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-510AVB Position Verification 55 Address Public Qti/Ct 56 Q ues ti ons/C ommen t s Adjourn 57

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