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Category:Slides and Viewgraphs
MONTHYEARML24248A2112024-09-0303 September 2024 2023 Davis-Besse End-of-Cycle Meeting Presentation ML23152A2022023-06-0101 June 2023 2022 Davis-Besse End-of-Cycle Meeting Presentation ML22222A1102022-07-21021 July 2022 KM Session Final ML22178A1952022-06-27027 June 2022 2021 Davis Besse Nuclear Power Station End-of-Cycle Meeting Presentation ML22028A3922022-02-0101 February 2022 Licensee Regulatory Conference Presentation ML22028A3972022-02-0101 February 2022 NRC Regulatory Conference Presentation ML21176A1992021-06-25025 June 2021 Slideshow Presentation for 2020 End -of-Cycle Public Meeting for Davis-Besse and Perry ML20210M0712020-07-27027 July 2020 Combined End-of-Cycle 2019 Public Meeting Slide Presentation ML19249D0212019-09-0606 September 2019 End-of-Cycle Summary Handout (2018) ML18310A3802018-11-0808 November 2018 Pre-Submittal Meeting Davis-Besse Nuclear Power Station (DB) Post-Shutdown Emergency Plan (PSEP) License Amendment Request ML18180A1962018-06-29029 June 2018 Slides for Davis Besse 2017 EOC Open House ML17229B3382017-08-17017 August 2017 Presentation for 2016 Davis-Besse EOC Open House ML16174A3152016-06-21021 June 2016 Annual Assessment Meeting Open House June 21, 2016 ML16117A1822016-04-22022 April 2016 Industry Slides for the Spring 2016 Conference Call Regarding the Steam Generator Tube Inservice Inspections ML15156A6962015-06-11011 June 2015 Annual Assessment Meeting Open House Handout ML14224A1112014-08-25025 August 2014 Safety Culture Presentation for Brazil, U.S. Workshop on Safety and Security Culture - August 25, 2014 ML14218A0542014-08-0707 August 2014 Handout Davis-Besse EOC Mtg ML14050A4002014-02-20020 February 2014 NRC Presentation for Davis-Besse Steam Generator Replacement Webinar ML13322B3112013-11-13013 November 2013 NFPA 805 Transition - Meeting Slides, 11/13/2013 ML13294A5972013-10-21021 October 2013 FENOC Presentation Slides for Public Meeting September 24, 2013 ML13220A0632013-08-30030 August 2013 Dsd ED2013 3267 Presentation, Primary Water Stress Corrosion Cracking Tests and Metallurgical Analyses of Davis-Besse Control Rod Drive Mechanism Nozzle #4. ML13157A0642013-06-0606 June 2013 June 11, 2013 NRC Presentation ML13159A0092013-06-0404 June 2013 Notable Failures in Nondustructive Testing - June 4, 2013 Public Meeting ML13078A2492013-03-20020 March 2013 Project Overview-Public Mtg 3-20-13 Non Proprietary ML12269A0612012-09-26026 September 2012 FENOC Presentation for 2012-09-26 Public Meeting ML12227A4172012-08-15015 August 2012 NRC End-Of-Cycle Assessment 2011 Meeting Presentation ML12221A2682012-08-0909 August 2012 FENOC Shield Building Cracking Davis-Besse Public Meeting 8/9/12 ML12221A2642012-08-0909 August 2012 NRC Public Meeting NRC Presentation 8/9/12 ML12138A0732012-05-14014 May 2012 FENOC-Davis-Besse Nuclear Power Station, Unit 1 Docket No. 50-346, License No. NPF-3 Submittal of Contractor Root Cause Assessment Report-Section 5 ML12132A3442012-05-11011 May 2012 NRC-AERB Bilateral Meeting Slide Presentation (Nro/De), Aerb, India - May 16-17, 2012 ML1206901712012-02-29029 February 2012 Slides and View Graphs - Boric Acid Corrosion Testing Program: Industry Perspective ML12200A2402012-02-23023 February 2012 Presentation Slides on Davis-Besse Shield Building Crack ML1204402842012-02-16016 February 2012 Public Meeting Construction Experiences - Evaluate Impact of Concrete Degradation ML1200501462012-01-0505 January 2012 Public Meeting FENOC Slides ML12004A0102012-01-0404 January 2012 Public Meeting NRC Slides ML12200A2492011-12-22022 December 2011 Presentation Slides on Shield Building /Containment Delamination ML11220A2542011-08-0101 August 2011 DBNPS-Info Meeting Slides ML11221A3012011-08-0101 August 2011 521- R326C B&W Tech Cross Training - Chapter 16 Davis-Besse Loss of All Feedwater ML1117303602011-06-21021 June 2011 FENOC Licensee Slides for 6-21-11 All FENOC Meeting ML1116400632011-06-15015 June 2011 EOC NRC Slides for Public Meeting ML1117209902011-06-15015 June 2011 Meeting Presentation NRC Annual Assessment Meeting: Davis-Besse Nuclear Power Station. ML1032103472010-11-16016 November 2010 FENOC 11/16/10 Public Meeting Presentation Slides ML1025103462010-09-0909 September 2010 SIT Exit Meeting Presentation Slides ML1021501182010-07-29029 July 2010 Licensee Slides for Davis-Besse Annual Assessment Meeting ML1021501112010-07-29029 July 2010 NRC Slides for Davis-Besse; July 29, 2010; Annual Assessment Meeting ML1015400332010-06-0303 June 2010 Licensee Slides for June 3, 2010 Public Meeting Presentation ML1015400342010-06-0303 June 2010 NRC Slides for June 3, 2010 Public Meeting Presentation ML1009102662010-03-31031 March 2010 Slides FENOC and NRC Senior Management Briefing, 3-31-10 ML0920202872009-07-15015 July 2009 Meeting Slides, NRC Annual Assessment Meeting Davis-Besse Nuclear Power Station ML0920202972009-07-15015 July 2009 NRC Slides from EOC Meeting 2024-09-03
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DAVIS-BESSE RPV HEAD CORROSION ACTIVITIES:
STATUS AND FUTURE PLANS ON VHP NOZZLE AND RPV HEAD INSPECTIONS Brian Sheron US Nuclear Regulatory Commission Office of Nuclear Reactor Regulation NRC/INPO Conference August 29, 2002
BACKGROUND ON VHP NOZZLE CRACKING
& RPV HEAD DEGRADATION HISTORY
First cracking of CRDM nozzles identified in France in 1991 - axial cracking
Industry analyses - axial cracking not a safety concern; circ. cracking unlikely
NRC issued Generic Letter 97-01
Spring 2001 Outages -- Circumferential flaws detected (boric acid deposits)
< Oconee Units 2 & 3 - 2 nozzles 165E through-wall cracks
< Chronology of circumferential cracks Axial cracks in J-groove welds or HAZ allow leakage into annular region Leakage to vessel head OD may be restricted by interference fit of nozzles Circumferential cracks initiate on OD and grow in aggressive environment
NRC issued Bulletin 2001-01 (August 2001) - inspections for circumferential cracks
Spring 2002 Outages - vessel head degradation identified at Davis-Besse
NRC issued Bulletin 2002-01 (March 2002) - no head degradation at other plants
NRC issued Bulletin 2002-02 (August 9, 2002) - inspections to prevent leakage Typical Reactor Vessel Head - Oconee Unit 1 (Babcock & Wilcox)
Schematic View of B&W Design CRDM Nozzle Area FUTURE INSPECTIONS
Management by leakage detection not considered sufficient
< Visual examination inspectability
< Insufficient Davis-Besse root cause report
< Technical specification limit of no pressure boundary leakage
Need further information to support visual examinations alone
< On-going MRP activities
< Support not sufficiently mature at this time
< Lack of understanding about wastage (corrosion) rates
< Lack of predictive models for crack growth in welds
< Cracking is becoming more prevalent as plants age BULLETIN 2002-02 EXAMPLE INSPECTIONS
High Susceptibility Plants ( > 12 EDY) - ~ 33 plants
< UT of nozzle base metal every RFO
< Surface examination (eddy current or PT) every RFO
< Bare metal visual every RFO
Moderate Susceptibility Plants ( > 8 EDY & <12 EDY) - ~ 15 plants
< UT of nozzle base metal at RFO after next RFO and then every other RFO
< Surface examination (eddy current or PT) at RFO after next RFO and then every other RFO
< Bare metal visual at next RFO and then every other RFO
Low Susceptibility Plants ( < 8 EDY) - ~ 21 plants
< UT of nozzle base metal within 5 years and then at least once every 5 years
< Surface examination (eddy current or PT) within 5 years and then at least once every 5 years
< Bare metal visual within 3 years and then at least once every 5 years PLANNED SUPPLEMENT TO BULLETIN 2002-01
Bulletin 2002-01 issued March 18, 2002
< Within 60-days: Describe boric acid corrosion prevention program for ensuring integrity of reactor coolant pressure boundary
Licensee responses inadequate due to:
< Lack of specificity regarding BAC prevention programs Inspection techniques Scope and frequency of inspections Degree of insulation removal Evaluation criteria Corrective actions
< Staff could not make a reasonable assurance finding that the boric programs have been implemented effectively.
OUTLOOK FOR ADDRESSING VHP NOZZLE AND RPV HEAD INSPECTIONS
Review Bulletin 2002-02 responses - status of inspection plans
< Pursue regulatory actions for plants with inadequate inspections
Develop technical basis to support inspection programs
Pursue changes to ASME Section XI
< Section XI Task Group on Alloy 600/182/82 Issues
< Request for formation of task group on changes to inspection requirements Insulation removal Inaccessible components Local corrosion areas
Revise 10 CFR 50.55a as appropriate INDUSTRY NEEDS TO TAKE MORE PROACTIVE ACTIONS TO ADDRESS ISSUES
Industry needs to provide adequate technical justification to reduce necessary reliance on supplemental non-visual examinations
New heads with Inconel 690 tubes will have to follow the same inspection criteria as head with Inconel 600 until industry provides technical basis for changes NRC WEB-SITE INFORMATION Alloy 600 Cracking (including Circumferential Cracking of CRDM Nozzles) http://www.nrc.gov/reactors/operating/ops-experience/alloy600.html RPV Head Degradation http://www.nrc.gov/reactors/operating/ops-experience/vessel-head-degradation.html