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| l 2 l 10 CFR 50.55a(g)(6)(1), the Commission may grant relief and may impose i alternative requirements that are determined to be authorized by law, will not l endanger life, property, or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed. | | l 2 l 10 CFR 50.55a(g)(6)(1), the Commission may grant relief and may impose i alternative requirements that are determined to be authorized by law, will not l endanger life, property, or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed. |
| Pursuant to 10 CFR 50.55a(a)(3), by letter dated November 25, 1996, Florida Power Corporation (FPC or the licensee), requested approval for implementing the alternative rules of ASME Section XI Code Case N-524, " Alternative Examination Requirements for Longitudinal Welds in Class 1 and 2 Piping Section XI, Division 1," dated August 9, 1993, to be applied to the ISI program for CR3. | | Pursuant to 10 CFR 50.55a(a)(3), by {{letter dated|date=November 25, 1996|text=letter dated November 25, 1996}}, Florida Power Corporation (FPC or the licensee), requested approval for implementing the alternative rules of ASME Section XI Code Case N-524, " Alternative Examination Requirements for Longitudinal Welds in Class 1 and 2 Piping Section XI, Division 1," dated August 9, 1993, to be applied to the ISI program for CR3. |
| The staff has reviewed and evaluated the licensee's request and supporting information to use Code Case N-524. | | The staff has reviewed and evaluated the licensee's request and supporting information to use Code Case N-524. |
| 2.0 DISCUSSION CODE CASE N-524 ALTERNATIVE EXAMINATION RE0VIREMENTS FOR LONGITUDINAL WELDS IN CLASS 1 AND 2 PIPING - Sf1 TION XI. DIVISION 1 Component Identification Longitudinal Welds in Class 1 and 2 Piping: | | 2.0 DISCUSSION CODE CASE N-524 ALTERNATIVE EXAMINATION RE0VIREMENTS FOR LONGITUDINAL WELDS IN CLASS 1 AND 2 PIPING - Sf1 TION XI. DIVISION 1 Component Identification Longitudinal Welds in Class 1 and 2 Piping: |
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Category:SAFETY EVALUATION REPORT--LICENSING & RELATED ISSUES
MONTHYEARML20217G0191999-10-15015 October 1999 Safety Evaluation Concluding That Licensee Followed Analytical Methods Provided in GL 90-05.Grants Relief Until Next Refueling Outage,Scheduled to Start on 991001.Temporary non-Code Repair Must Then Be Replaced with Code Repair ML20212L0881999-10-0404 October 1999 SER Accepting Licensee Requests for Relief 98-012 to 98-018 Related to Implementation of Subsections IWE & Iwl of ASME Section XI for Containment Insp for Crystal River Unit 3 ML20212J8631999-10-0101 October 1999 Safety Evaluation Supporting Licensee Proposed Alternatives to Provide Reasonable Assurance of Structural Integrity of Subject Welds & Provide Acceptable Level of Quality & Safety.Relief Granted Per 10CFR50.55a(g)(6)(i) ML20212E6911999-09-21021 September 1999 Safety Evaluation Supporting Proposed EALs Changes for Plant Unit 3.Changes Meet Requirements of 10CFR50.47(b)(4) & App E to 10CFR50 ML20210P1111999-08-0505 August 1999 SER Accepting Evaluation of Third 10-year Interval Inservice Insp Program Requests for Relief for Plant,Unit 3 ML20203A4381999-02-0303 February 1999 Safety Evaluation Supporting EAL Changes for License DPR-72, Per 10CFR50.47(b)(4) & App E to 10CFR50 ML20236Q4611998-06-30030 June 1998 SER for Crystal River Power Station,Unit 3,individual Plant Exam (Ipe).Concludes That Plant IPE Complete Re Info Requested by GL 88-20 & IPE Results Reasonable Given Plant Design,Operation & History ML20216G8091998-04-10010 April 1998 Safety Evaluation Accepting Resolution of Crystal River Restart Issues Related to USI A-46 Program ML20199A1441998-01-0909 January 1998 Safety Evaluation Accepting Relief Request for Delayed Implementation of 10CFR50.55a,until 971231 or Plant Restart, Whichever Occurs First ML20199D0561997-11-14014 November 1997 Safety Evaluation Approving Ampacity Derating Test Results for Crystal River,Unit 3 Related to GL 92-08, Thermo-Lag 330-1 Fire Barriers ML20212C3751997-10-16016 October 1997 SER Accepting Licensee Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves ML20217D7561997-10-0101 October 1997 Safety Evaluation Concluding That Testing of Ingersoll-Dresser Pump Model 8HN194 at Test Facility Demonstrates That Crystal River Decay Heat Pumps of Same Model Can Operate at Flows of 100 Gpm for 30 Days ML20138J0151997-05-0505 May 1997 Safety Evaluation Approving Request for Relief 95-050,Rev 1, for Plant,Unit 3 ML20138E4411997-04-30030 April 1997 Safety Evaluation on ASME Code Case N-509 for Crystal River Nuclear Plant,Unit 3 ML20140F3771997-04-28028 April 1997 Safety Evaluation Supporting Staff Evaluation of Plant, Unit 3 Nuclear Generating Plant IPE ML20134B7091997-01-29029 January 1997 SER Accepting Fire Barrier Sys Relied by Licensee to Meet NRC Fire Protection Requirements for Following Raceway Types & Sizes ML20133N6511997-01-22022 January 1997 Safety Evaluation Accepting Licensee Request to Use Code Case N-524 as Alternative to ASME Code Section XI for Plant ML20149M6801997-01-17017 January 1997 Safety Evaluation Accepting Licensee 960807 Results of Analyses Re Operability Evaluation of Main Steam Sys W/Bent Rod Hangers at Plant ML20133D3471997-01-0606 January 1997 Safety Evaluation Supporting Amend 155 to License DPR-72 ML20058P1981993-12-16016 December 1993 Safety Evaluation Accepting Ground Response Spectra Utilized & Approaches Used in Development of Floor Response Spectra for Resolution of USI A-46 ML20138D5941993-02-0909 February 1993 Safety Evaluation Granting Relief from Repair Requirements of ASME Code Section XI in Order to Perform Temporary Noncode Repair to 18 Inch Portion of Nuclear Closed Cycle Cooling Sys ML20126F7811992-12-22022 December 1992 Safety Evaluation to Confirm Granting of Request for Relief from ASME Code Repair Requirements Nuclear Closed Cycle Cooling Sys ML20056B5341990-08-23023 August 1990 Safety Evaluation Re Station Blackout.Recommends That Util Reevaluate Areas of Nonconformance W/Station Blackout Guidance Identified in Evaluation.Subj to Acceptable Resolution of NRC Recommendations,Issue Remains Open ML20055E5141990-07-0202 July 1990 Safety Evaluation Re Util 831104 & 840731 Responses to Generic Ltr 83-28,Item 2.2.1 Re Equipment Classification Programs for All safety-related Components ML20245F6561989-06-22022 June 1989 Safety Evaluation Supporting Amend 118 to License DPR-72 ML20245D3001989-06-14014 June 1989 Safety Evaluation Concluding That Licensee Meets NRC Position on Item 4.5.2 of Generic Ltr 83-28,based on Finding That Facility Will Be Designed to Permit on-line Functional Testing of Reactor Trip Sys,Including Stated Testing ML20247D4951989-05-19019 May 1989 Safety Evaluation Re TMI Action Item II.K.3.31 Concerning plant-specific Calculations to Show Compliance w/10CFR50.46 ML20245A6161989-04-19019 April 1989 Safety Evaluation Supporting Util 890210 Final ATWS Design Description ML20155F2641988-10-0606 October 1988 Safety Evaluation Supporting Relief from Inservice Testing Program ML20154A7421988-04-29029 April 1988 Evaluation of Auxiliary Feedwater Sys Reliability (Generic Issue 124).Licensee Should Consider Listed Addl Recommendations for Improved Plant Performance & Auxiliary Feedwater Sys Challenge Rate Reduction ML20234D5221987-06-16016 June 1987 Safety Evaluation Re Conformance to Reg Guide 1.97 ML20214Q7731987-05-29029 May 1987 Ser:Pump & Valve Inservice Testing Program,Crystal River Nuclear Power Station,Unit 3,for Remainder of First 10-Yr Interval ML20214M1781987-05-26026 May 1987 Safety Evaluation Granting Util 860324 & 870114 Requests for Relief from Certain Requirements of ASME Code Section XI & to Use ANSI N45.2.6-1978 in Lieu of ASME Code Requirement of ANSI N45.2.6-1973 ML20211N2661987-02-19019 February 1987 Evaluation of Licensee Response to Insp Rept 50-302/86-12. Procedure AI-401 Found to Be Inadequate & Resulted in Restatement of Violation 2.Design Error Could Cause Loss of RHR Ability ML20211Q2971987-02-18018 February 1987 Safety Evaluation Re Auxiliary Feedwater Sys Reliability (Generic Issue 124) for Prairie Island Units 1 & 2 ML20211B5521987-02-0909 February 1987 Safety Evaluation Re Rev 7 to Offsite Dose Calculation Manual (ODCM) & Rev 0 to Process Control Program (Pcp).Odcm & PCP Acceptable Refs for Use W/Tech Specs for Assuring Compliance w/10CFR20 & 50,App a & I ML20209H7051987-01-16016 January 1987 Safety Evaluation of Util 831104,840116 & 0731 Responses to Generic Ltr 83-28,Item 4.4 Re safety-related Maint & Test Procedures for Diverse Reactor Trip Feature.Responses Acceptable ML20207Q6451987-01-0909 January 1987 Safety Evaluation Supporting Util 831104,840116 & 0731 Responses to Generic Ltr 83-28,Item 4.4 Re Maint & Test Procedures for Silicon Controlled Rectifiers ML20214N1941986-09-0404 September 1986 Safety Evaluation Supporting Licensee 860117 Response to 10CFR50.61 Re Projected Values of Matl Properties for Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events ML20205T5301986-06-0909 June 1986 SER Supporting Responses to Generic Ltr 83-28,Items 4.2.1 & 4.2.2 Re Reactor Trip Sys Reliability ML20211D6251986-06-0909 June 1986 SER Supporting Responses to Generic Ltr 81-21 Re Natural Circulation Cooldown ML20210R9531986-05-0202 May 1986 SER Supporting Util Response to IE Bulletin 80-11 Re Masonry Wall design.Safety-related Masonry Walls Will Withstand Specified Design Load Conditions W/O Impairment of Wall Integrity.Technical Evaluation Rept Encl ML20133Q1271985-10-24024 October 1985 SER Re Generic Ltr 83-28,Item 1.1 Post-Trip Review Program Description & Procedure. Util 831104 Response to Generic Ltr 83-28 Does Not Meet Guidelines for post-trip Review. Acceptable Responses Required ML20135F8871985-09-11011 September 1985 SER Re Control Complex Dedicated Cooling Sys for post-fire Alternate Shutdown Capability.Design of Control Complex Dedicated Cooling Sys Meets Requirements of Section III.G.3 & Iii.L of 10CFR50 App R & Acceptable ML20135G1051985-09-0909 September 1985 SER Supporting Licensee Response to Items 3.1.1,3.1.2,3.2.1, 3.2.2,4.1 & 4.5.1 of Generic Ltr 83-28, Required Actions Based on Generic Implications of Salem ATWS Events ML20135E6131985-09-0606 September 1985 SER Re Licensee Response to Generic Ltr 83-28,Item 1.2 Re post-trip Review (Data & Info Capability).Licensee Program for Data Retention Conforms to Guidelines of Section Ii.D & Acceptable ML20214J2911979-12-20020 December 1979 Safety Evaluation Re Preliminary Design for safety-grade Anticipatory Reactor Trips on Loss of Main Feedwater &/Or Turbine Trip 1999-09-21
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217G0191999-10-15015 October 1999 Safety Evaluation Concluding That Licensee Followed Analytical Methods Provided in GL 90-05.Grants Relief Until Next Refueling Outage,Scheduled to Start on 991001.Temporary non-Code Repair Must Then Be Replaced with Code Repair 3F1099-19, Part 21 Rept Re Damage on safety-grade Cable Provided to FPC by Bicc Brand-Rex Co.Damage Was Created During Cabling Process While Combining Three Conducters.Corrective Action Program Precursor Card PC99-2868 Was Initiated1999-10-13013 October 1999 Part 21 Rept Re Damage on safety-grade Cable Provided to FPC by Bicc Brand-Rex Co.Damage Was Created During Cabling Process While Combining Three Conducters.Corrective Action Program Precursor Card PC99-2868 Was Initiated ML20217B0931999-10-0606 October 1999 Part 21 Rept Re Damaged Safety Grade Electrical Cabling Found in Supply on 990831.Damage Created During Cabling Process While Combining Three Conductors Just Prior to Closing.Vendor Notified of Reporting of Issue ML20212L0881999-10-0404 October 1999 SER Accepting Licensee Requests for Relief 98-012 to 98-018 Related to Implementation of Subsections IWE & Iwl of ASME Section XI for Containment Insp for Crystal River Unit 3 ML20212J8631999-10-0101 October 1999 Safety Evaluation Supporting Licensee Proposed Alternatives to Provide Reasonable Assurance of Structural Integrity of Subject Welds & Provide Acceptable Level of Quality & Safety.Relief Granted Per 10CFR50.55a(g)(6)(i) ML20212E9031999-09-30030 September 1999 FPC Crystal River Unit 3 Plant Reference Simulator Four Year Simulator Certification Rept Sept 1995-Sept 1999 3F1099-02, Monthly Operating Rept for Sept 1999 for Crystal River,Unit 3.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Crystal River,Unit 3.With ML20212E6911999-09-21021 September 1999 Safety Evaluation Supporting Proposed EALs Changes for Plant Unit 3.Changes Meet Requirements of 10CFR50.47(b)(4) & App E to 10CFR50 ML20211L1321999-08-31031 August 1999 EAL Basis Document 3F0999-02, Monthly Operating Rept for Aug 1999 for Crystal River,Unit 3.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Crystal River,Unit 3.With ML20212C1501999-08-31031 August 1999 Non-proprietary Version of Rev 0 to Crystal River Unit 3 Enhanced Spent Fuel Storage Engineering Input to LAR Number 239 ML20211B7291999-08-16016 August 1999 Rev 2 to Cycle 11 Colr ML20210P1111999-08-0505 August 1999 SER Accepting Evaluation of Third 10-year Interval Inservice Insp Program Requests for Relief for Plant,Unit 3 ML20210U5341999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Crystal River,Unit 3 ML20209F5601999-07-31031 July 1999 EAL Basis Document, for Jul 1999 3F0799-01, Monthly Operating Rept for June 1999 for Crystal River,Unit 3.With1999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Crystal River,Unit 3.With ML20210U5411999-06-30030 June 1999 Revised Monthly Operating Rept for June 1999 for Crystal River,Unit 3 3F0699-07, Monthly Operating Rept for May 1999 for Crystal River,Unit 3.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Crystal River,Unit 3.With ML20210U5601999-05-31031 May 1999 Revised Monthly Operating Rept for May 1999 for Crystal River,Unit 3 ML20195C6271999-05-28028 May 1999 Non-proprietary Rev 0 to Addendum to Topical Rept BAW-2346P, CR-3 Plant Specific MSLB Leak Rates ML20196L2031999-05-19019 May 1999 Non-proprietary Rev 0 to BAW-2346NP, Alternate Repair Criteria for Tube End Cracking in Tube-to-Tubesheet Roll Joint of Once-Through Sgs 3F0599-04, Monthly Operating Rept for Apr 1999 for Crystal River Unit 3.With1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Crystal River Unit 3.With ML20210U5631999-04-30030 April 1999 Revised Monthly Operating Rept for Apr 1999 for Crystal River,Unit 3 3F0499-04, Monthly Operating Rept for Mar 1999 for Crystal River Unit 3.With1999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Crystal River Unit 3.With ML20204D9661999-03-31031 March 1999 Non-proprietary Rev 1,Addendum a to BAW-2342, OTSG Repair Roll Qualification Rept 3F0399-04, Special Rept 99-01:on 990310,discovered Containment Tendons That Required Grease Addition in Excess of Prescribed Limits During Recent Insp Activites.Six Tendons Were Refilled with Appropriate Amount of Grease1999-03-10010 March 1999 Special Rept 99-01:on 990310,discovered Containment Tendons That Required Grease Addition in Excess of Prescribed Limits During Recent Insp Activites.Six Tendons Were Refilled with Appropriate Amount of Grease 3F0399-03, Monthly Operating Rept for Feb 1999 for Crystal River Unit 3.With1999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for Crystal River Unit 3.With ML20203A4381999-02-0303 February 1999 Safety Evaluation Supporting EAL Changes for License DPR-72, Per 10CFR50.47(b)(4) & App E to 10CFR50 ML20206E9891998-12-31031 December 1998 Kissimmee Utility Authority 1998 Annual Rept ML20206E9021998-12-31031 December 1998 Florida Progress Corp 1998 Annual Rept ML20206E9701998-12-31031 December 1998 Ouc 1998 Annual Rept. with Financial Statements from Seminole Electric Cooperative,Inc 3F0199-05, Monthly Operating Rept for Dec 1998 for Crystal River Unit 3.With1998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for Crystal River Unit 3.With ML20206E9261998-12-31031 December 1998 Gainesville Regional Utilities 1998 Annual Rept 3F1298-13, Monthly Operating Rept for Nov 1998 for Crystal River,Unit 3.With1998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for Crystal River,Unit 3.With 3F1198-05, Monthly Operating Rept for Oct 1998 for Crystal River,Unit 3.With1998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for Crystal River,Unit 3.With ML20155F4071998-10-31031 October 1998 Rev 2 to Pressure/Temp Limits Rept ML20155J2701998-10-28028 October 1998 Second Ten-Year Insp Interval Closeout Summary Rept 3F1098-06, Monthly Operating Rept for Sept 1998 for Crystal River Unit 3.With1998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for Crystal River Unit 3.With ML20206E9461998-09-30030 September 1998 Utilities Commission City of New Smyrna Beach,Fl Comprehensive Annual Financial Rept Sept 30,1998 & 1997 ML20206E9561998-09-30030 September 1998 City of Ocala Comprehensive Annual Financial Rept for Yr Ended 980930 ML20206E9101998-09-30030 September 1998 City of Bushnell Fl Comprehensive Annual Financial Rept for Fiscal Yr Ended 980930 ML20206E9811998-09-30030 September 1998 City of Tallahassee,Fl Comprehensive Annual Financial Rept for Yr Ended 980930 ML20195E3121998-09-30030 September 1998 Comprehensive Annual Financial Rept for City of Leesburg,Fl Fiscal Yr Ended 980930 3F0998-07, Monthly Operating Rept for Aug 1998 for Crystal River Unit 3.With1998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for Crystal River Unit 3.With ML20236W6501998-07-31031 July 1998 Emergency Action Level Basis Document 3F0898-02, Monthly Operating Rept for Jul 1998 for Crystal River,Unit 11998-07-31031 July 1998 Monthly Operating Rept for Jul 1998 for Crystal River,Unit 1 ML20236V8801998-07-30030 July 1998 Control Room Habitability Rept 3F0798-01, Monthly Operating Rept for June 1998 for Crystal River Unit 31998-06-30030 June 1998 Monthly Operating Rept for June 1998 for Crystal River Unit 3 ML20236Q4611998-06-30030 June 1998 SER for Crystal River Power Station,Unit 3,individual Plant Exam (Ipe).Concludes That Plant IPE Complete Re Info Requested by GL 88-20 & IPE Results Reasonable Given Plant Design,Operation & History 3F0698-02, Monthly Operating Rept for May 1998 for Crystal River Unit 31998-05-31031 May 1998 Monthly Operating Rept for May 1998 for Crystal River Unit 3 1999-09-30
[Table view] |
Text
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p 4 UNITED STATES g j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20006 0001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ON ASME CODE CASE N-524 CRYSTAL RIVER NUCLEAR PLANT UNIT NO. 3 FLORIDA POWER CORPORATION DOCKET NO: 50-302
1.0 INTRODUCTION
The Technical Specifications (TS) for the Crystal River Nuclear Plant, Unit 3 i (CR3), state that the inservice inspection and testing of the American Society l of Mechanical Engineers (ASME) Code Class 1, 2, and 3 components shall be '
performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Code and applicable addenda as required by 10 CFR 50.55a(g), except where specific written relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). 10 CFR 50.55a(a)(3) states that alternatives to the requirements of paragraph (g) may be used, when authorized by the NRC, if (i) the proposed alternatives would provide an acceptable level of quality and l safety, or (ii) compliance with the specified requirements would result in !
hardship or unusual difficulties without a compensating increase in the level l of quality and safety. j Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components .
(including supports) shall meet the requirements, except the design and access !
provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, " Rules for Inservice Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materia h of construction of the components. The regulations require that inservice examination of components and system pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of the ASME Co#
Section XI incorporated by reference in 10 CFR 50.55a(b) on the date 11 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The applicable ASME Code Section XI edition for CR3, during the second 10-year inservice inspection (ISI) interval is the 1983 Edition though the Summer 1983 Addenda. The components (including supports) may meet the requirements set forth in subsequent editions and addenda of the ASME Code incorporated by reference in 10 CFR 50.55a(b) subject to the limitations and modifications listed therein and subject to Commission approval.
Pursuant to 10 CFR 50.55a(g)(5), if a licensee determines that conformance with an examination requirement of the ASME Section XI is not practical for its facility, information shall be submitted to the Commission in support of that determination and a request made for relief from the ASME Code requirement. After evaluation of the determination, pursuant to 9701230362 970122 PDR ADOCK 05000302 P PDR
l l
l 2 l 10 CFR 50.55a(g)(6)(1), the Commission may grant relief and may impose i alternative requirements that are determined to be authorized by law, will not l endanger life, property, or the common defense and security, and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed.
Pursuant to 10 CFR 50.55a(a)(3), by letter dated November 25, 1996, Florida Power Corporation (FPC or the licensee), requested approval for implementing the alternative rules of ASME Section XI Code Case N-524, " Alternative Examination Requirements for Longitudinal Welds in Class 1 and 2 Piping Section XI, Division 1," dated August 9, 1993, to be applied to the ISI program for CR3.
The staff has reviewed and evaluated the licensee's request and supporting information to use Code Case N-524.
2.0 DISCUSSION CODE CASE N-524 ALTERNATIVE EXAMINATION RE0VIREMENTS FOR LONGITUDINAL WELDS IN CLASS 1 AND 2 PIPING - Sf1 TION XI. DIVISION 1 Component Identification Longitudinal Welds in Class 1 and 2 Piping:
Examination Category B-J, in Table IWB-2500-1, Item Nos B9.12 and B9.22 Examination Category C-F, in Table IWC-2500-1, Item Nos C5.12, C5.22 and C5.32 of ASME Code,Section XI, 1983 Edition through Summer 1983 Addenda.
Code Reauirement and Relief Reauest: (As stated by the licensee)
"ASME Section XI 1983 Edition, Table IWB-2500-1, Examination Category B-J requires examination (surface and volumetric for piping 2 4 inches in diameter and surface only for piping < 4 inches in diameter) of at least one pipe diameter length but not more than 12 inches of each longitudinal weld in piping intersecting circumferential piping welds required to be examined by Examination Categories B-F and B-J.
"ASME Section XI 1983 Edition, Table IWC-2500-1, Examination Category C-F, Item C5.22 requires surface and volumetric examination for piping > 1/2 inch nominal wall thickness. Category C-F, Item C5.12 requires surface examination only for piping s 1/2 inch nominal wall thickness and Item C5.32 requires surface examination of pipe branch connections > 4 inches in diameter branch pipe size. The extent of examination includes at least the length of longitudinal welds equal to 2.5t, at the intersection of the circumferential weld, where 't' is a measure of the pressure boundary thickness.
" Relief is requested from performing the Code-required examination for longitudinal welds in Class 1 and 2 piping. FPC is proposing to adopt the l extent of examinaticn for longitudinal welds in Categories B-J and C-F defined by Code Case N-524."
l l
. 3 Licensee's Basis for Relief (As stated)
" Florida Power Corporation is requesting relief from the above stated requirements based on ASME Section XI Code Case N-524 which has been issued by the American Society of Mechanical Engineers and has been included in the 1995 Addenda of Section XI. Code Case N-524 defines alternative examination requirements that may be applied to surface l and volumetric examination of longitudinal welds in Class 1 and Class 2 l piping.
" Code Case N-524 directs examination efforts at the high risk area at weld intersections. By eliminating the low risk areas of longitudinal welds from examination, the time requirments and radiation exposure of personnel are )
significantly reduced. The expected dose savings is estimated to be 1.6 to l 2.0 man-rem per weld with a projected outage savings of 12.8 to 16.0 man-rem l based on examination of eight longitudinal welds. Compliance with the existing ASME Section XI requirements, in lieu of Code Case N-524, would result in unnecessary exposure without a compensating increase in the level of quality or safety.
" Longitudinal welds are produced during pipe fabrication, as opposed to circumferential welds which are field produced. The ASME Code contains requirements for characteristics and performance of materials and components, l
and for examination of longitudinal piping welds during fabrication. l Additionally, the ASME Code specifies the minimum chemical and physical i properties of the material to ensure structural integrity of the longitudinal j welds at the time of pipe fabrication.
"The preservice, and inservice examinations conducted during the first ISI interval provide assurance of longitudinal weld structural integrity for the service life of the plant to date.
i " Experience within the United States reveals that ASME Code longitudinal welds have not experienced degradation warranting inservice examination beyond that required to meet the circumferential weld examination requirements. To date, no significant loading conditions or material degradation mechanisms have become evident that specifically relate to longitudinal seam welds in nuclear power plant piping. If degradation of a longitudinal weld was to occur, it is expected to be located at an intersection with a circumferential weld, which is inspected in accordance with Code Case N-524. Therefore, the health and safety of the public will continue to be maintained while implementing the l alternative examination requirements of Code Case N-524."
l Licensee's Alternate Examination (As stated)
"The following alternative examination requirements will be performed as
, defined in ASME Section XI Code Case N-524:
l a) When only a surface examination is required, examination of longitudinal i piping welds is not required beyond those portions of the welds within
! the examination boundaries of intersecting circumferential welds.
I
. 4 b) When both surface and volumetric examinations are required, examination 4
j of longitudinal piping welds is not required beyond those portions of the welds within the examination boundaries of intersecting
] circumferential welds provided the following requirements are met:
i
- 1) Where longitudinal welds are specified and locations are known, examination requirements shall be met for both transverse and parallel flaws at the intersection of the welds and for that length
. of longitudinal weld within the circumferential weld examination volume; l
- 2) Where longitudinal welds are specified but locations are unknown, or the existence of longitudinal welds is uncertain, the examination i requirements shall be met for both transverse and parallel flaws
- within the entire examination volume of intersecting circumferential j welds."
]
} 3.0 EVALUATION )
1 I
The ASME Section XI Code (1983 Edition) requires one pipe diameter in length, i but no more than 12 inches, be examined for Class I longitudinal piping welds.
( Class 2 longitudinal piping welds are required to be examined for a length of i i 2.5t, where t is the thickness of the weld. These weld lengths are measured i
! from the intersection of the circumferential weld and longitudinal weld. The
- licensee's proposed alternative, Code Case N-524, limits the volumetric and !
l surface examination requirements of the longitudinal weld to the volume or i j area contained within the examination requirements of the intersecting
- circumferential weld. j
! Longitudinal welds are produced during the manufacturing process of the i
! piping, not in the field as is the case for circumferential welds. ASME (the ;
1 Code) provides requirements on characteristics and performance of materials ;
! and products, and specifies the examination requirements during the
] manufacturing of the subject longitudinal piping welds.
I
- In addition, there are material, chemical, and tensile strength requirements i in the Code. The manufacturing process that is specified by the Code provides ;
! assurance of the structural integrity of the longitudinal welds at the time the piping is manufactured.
i" The preservice examination and initial inservice examinations have provided the code-required assurance of the structural integrity of the longitudinal
! welds. The staff concurs with the licensee's assessment of the industry l experience in the United States relating to degradation of pipes with shop i welded longitudinal seams, that they do not warrant continued examination beyond the boundaries required to meet the circumferential weld examination
- requirements. No significant loading conditions or known material degradation
- mechanisms have become evident to date which specifically relate to 5
longitudinal seam welds in nuclear plant piping.
i If any degradation associated with a longitudinal weld were to occur, it is
! expected that it would be located at the intersection with a circumferential weld. This intersection is inspected in accordance with the provisions of
.]
i
- 5 Code Case N-524. Furthermore, the 1983 ASME Code,Section XI, Appendix III
" Ultrasonic Examination of Piping Systems" which is applicable to the subject plant, requires scanning for reflectors parallel and transverse to the weld seam in case of ferritic piping, contrary to the requirement in some older Code editions to only scan for reflectors oriented parallel to the weld seam.
The transverse scan of a circumferential weld, will further detect reflectors oriented parallel to a longitudinal weld at the root of intersection of a longitudinal seam.
4.0 CONCLUSION
Based on the above discussions, the staff concludes that the licensee's proposed use of Code Case N-524 as an alternative to the Code requirements, provides an acceptable level of quality and safety while eliminating personnel radiation exposure associated with the examination of longitudinal welds.
Therefore, the licensee's proposed alternative to use Code Case N-524 is authorized pursuant to 10 CFR 50.55a(a)(3)(i). The licensee is authorized to use Code Case N-524 until such time as the code case is included in a future revision of Regulatory Guide 1.147. At that time the licensee should follow all provisions and any limitations that may be described in the Regulatory Guide 1.147 concerning the use of Code Case N-524.
Principal Contributor: Prakash Patnaik, DE/NRR Date: January 22, 1997