SBK-L-21083, NextEra Energy Seabrook, LLC - Relief Request 3IR-18 and 3IR-19 for End of Third 10-Year ISI Interval for Examinations with Limited Coverage
| ML21230A157 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/18/2021 |
| From: | Levander M NextEra Energy Seabrook |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 3IR-18, SBK-L-21083 | |
| Download: ML21230A157 (52) | |
Text
{{#Wiki_filter:NEXTeraM EN~~~~ August 18, 2021 10 CFR 50.55a SBK-L-21083 Attention: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Seabrook Station Docket No. 50-443
Subject:
Relief Request 3IR-18 and 3IR-19 for End of Third IO-Year ISI Interval for Examinations with Limited Coverage NextEra Energy Seabrook, LLC (NextEra) concluded its third ten-year inservice inspection program on August 18, 2020. During this interval, components identified in Enclosures 1 and 2 received less than the required examination coverage. Therefore, pursuant to 10CFR50.55a(g)(5)(iii), NextEra requests relief on the basis that the required examination coverage is impractical due to physical obstructions and limitations imposed by design or geometry. Enclosures 1 and 2 contain relief requests and the basis for these requests. The relief requests are specifically identified as 3IR-18 and 3IR-19. There are no commitments being made in this submittal. If you have any questions regarding this submittal, please contact me at (603) 773-7631. Sincerely, NextEra Energy Sf brook, LL~
~~
Matthew Levander Licensing Manager : Relief Request 3IR-18 Limited Coverage Obtained for Piping Examinations : Relief Request 3IR-19 Limited Coverage Obtained for Class 1 & 2 Vessel Welds Examinations
United States Nuclear Regulatory Commission SBK-L-21083 I Page 2 cc: NRC Region I Administrator NRC Project Manager NRC Senior Resident Inspector
Enclosure 1 to SBK-L-21083 Relief Request Number 3IR-18 Relief Request 3IR-18, Limited Coverage Obtained for Piping Examinations
Enclosure 1 SBK-L-21083 Page 1 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Relief Request In Accordance with 10 CFR50.55a(g(5)iii)
--lnservice Inspection lmpracticality--
- 1. ASME Code Component(s) Affected Class 1 and 2 pressure retaining welds in piping
2. Applicable Code Edition and Addenda
The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Rules for lnservice Inspection of Nuclear Power Plant Components, Section XI, 2004 Edition with No Addenda as amended by 10CFR50.55a, is the code of record for the Seabrook Unit 1, 3rd 10-year interval. ASME Section XI, 2004 Edition with No Addenda as amended by 10CFR50.55a, was utilized for Appendix VIII.
3. Applicable Code Requirement
Exam Item No. Examination Requirements Cat. R1 .11 - Elements Subject to Thermal *Essentially 100% volumetric examination R-A Fatigue of the circumferential welds. R1 .16 - Elements Subject to lntergranular *Essentially 100% volumetric examination R-A Stress Corrosion Cracking of the circumferential welds. R1 .20 - Elements Not Subject to a Damage *Essentially 1 00% volumetric examination R-A Mechanism of the circumferential welds.
*As defined by ASME Code Case N-460, essentially 100% means more than 90% of the examination volume of each weld where reduction in coverage is due to interference by another component or part geometry.
The Seabrook Risk-Informed, Safety-Based ISi Program was developed based on the Electric Power Research Institute (EPRI) Topical Report (TR) 112657 Rev. B-A, [Ref. 2], with identified differences, and with additional guidance taken from ASME Code Case N-716. By letter dated November 7, 2011 (Accession No. ML11319A016), supplemented by letter dated March 8, 2012 (Accession No. ML12074A111), NextEra Energy Seabrook Station (Seabrook) submitted request for alternative 3AR-1 to the NRC, requesting relief from the ASME Section XI Code examination requirements for Class 1 and Class 2 piping weld (Examination Categories B-F, B-J, C-F-1, and C-F-2) inservice inspections by implementing a Risk-Informed, Safety-Based lnservice Inspection (RIS_B) Program. The NRC published a
Enclosure 1 SBK-L-21083 Page 2 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Safety Evaluation dated June 21, 2012 (Accession No. ML121320552, TAC No. ME7569) authorizing the use of a risk-informed, safety based inservice inspection (RIS_B) program for the third 10-year ISi interval at Seabrook. 10 CFR 50.55a(b)(2)(xv)(A) requires the following examination coverage when applying Supplement 2 to Appendix VIII: (1) Piping must be examined in two axial directions and when examination in the circumferential direction is required, the circumferential examination must be performed in two directions, provided access is available. (2) Where examination from both sides is not possible, full coverage credit may be claimed from a single side for ferritic welds. Where examination from both sides is not possible on austenitic welds, full coverage credit from a single side may be claimed only after completing a successful single side Appendix VIII demonstration using flaws on the opposite side of the weld. 10 CFR 50.55a (b)(2)(xvi)(B) requires that examinations performed from one side of a stainless-steel pipe weld must be conducted with equipment, procedures, and personnel that have demonstrated proficiency with single side examinations. To demonstrate equivalency to two sided examinations, the demonstration must be performed to the requirements of Appendix VIII as modified by this paragraph and paragraph 50.55a(b)(2)(xv)(A).
4. Impracticality of Compliance
Due to the configuration, it is not possible to meet the examination coverage requirements of the ASME Code, Section XI, 2004 Edition with No Addenda, as clarified by Code Case N-460. Relief is requested in accordance with 10CFR50.55a(g)(5)(iii). These areas were found during the 3rd 10-year inservice inspection interval. When a component has conditions, which limit the examination volume, NextEra Energy is required to submit the information to the enforcement and regulatory authorities having jurisdiction at the plant site. This Relief Request has been written to address areas where those types of conditions exist, and the required amount of coverage was reduced below the minimum acceptable. The welds listed in Table 1 within this request did not receive the required code volume coverage due to their configuration and/or the presence of permanent attachments, when examined. These scanning limitations prohibit essentially 100% ultrasonic examination coverage of the required examination volume. Table 1 included in this Relief Request summarizes the percent of coverage credited and references specific figures that show the extent of coverage.
Enclosure 1 SBK-L-21083 Page 3 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Relief is requested from the ASME Boiler and Pressure Vessel Code required volume as identified in figure IWB-2500-8. Additionally, in accordance with the Seabrook Risk Informed (RI) Program (ME7569), the Figure IWB-2500-8 exam volume is increased, when required, to include internal counterbore areas.
5. Burden Caused by Compliance
It is not possible to obtain ultrasonic interrogation of greater than 90% of the required examination volume due to interference caused by configuration and/or permanent attachments. Examinations are performed to the maximum extent possible. The Ultrasonic (UT) techniques for each weld were reviewed to determine if additional coverage could be achieved. For the welds listed in Table 1, NextEra Energy determined that removal of the obstruction was not possible without significant work, increased radiation exposure, and/or damage to the plant. Additional weld preparation by welding or metal removal is a modification of the examination area requiring significant engineering and construction personnel support. Radiography is impractical due to the amount of work being performed in the areas on a 24-hour basis. This would result in numerous work-related stoppages and increased exposure due to the shutdown of and startup of other work in the areas. The water must be drained from systems where radiography is performed, which increases the radiation dose rates over a much broader area than the weld being examined. There would be significant burden associated with the performance of weld or area modifications or radiography to increase the examination coverage.
6. Proposed Alternative and Basis for Use
Proposed Alternative
- 1) Periodic system pressure tests in accordance with ASME Section XI Category B-P, Table IWB-2500-1.
- 2) Conduct ultrasonic examinations to the maximum extent possible.
- 3) Regular walkdowns by operations personnel and system engineers are performed on systems outside containment to check for leakage, piping configuration, and/or damage.
During outages, system engineers walkdown systems inside and outside containment. This walkdown is performed to look for system anomalies that could affect plant performance. Basis The attached Table provides the percent of coverage credited and references specific figures that illustrate the extent of coverage for each weld. The examination figures of ASME Section XI, 2004 Edition with No Addenda, define the examination volume required. The system, diameter, pipe schedule and material are identified for each item within the Table. The angles, Ultrasonic wave modes (Shear-S or Longitudinal-L) that were employed for examination and
Enclosure 1 SBK-L-21083 Page 4 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS impracticality of compliance are listed for each weld. Arrows and lines on the figures illustrate the UT transducer beam direction and extent of the area examined. 10 CFR 50.55a(g)(4) recognizes that throughout the service life of a nuclear power facility, components which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements set forth in the ASME Code to the extent practical within the limitations of design, geometry and materials of construction of the components. Seabrook performed the examinations to the maximum extent possible. There is no plant-specific, NextEra fleet or industry operating experience regarding potential degradation specific to the subject welds included in this relief request. However, isolated occurrences of stress corrosion cracking have occurred in stainless steel materials in the industry. To address the concerns of these isolated cases, periodic walkdowns by plant personnel provide assurance that any isolated degradation would be identified at the onset before a safety concern could develop. The Class 1 items identified in the table are located within either the reactor containment building or reactor auxiliary building. Regular walkdowns by operations personnel and system engineers are performed on systems in the reactor auxiliary building to check for leakage, piping configuration, and/or damage. During outages, system engineers perform boric acid walkdowns of all systems inside containment. This walkdown is performed to look for borated system as well as system abnormalities that could affect plant performance. Also, a system pressure test and VT-2 visual examination is performed each refueling outage for Class 1 connections and each period for Class 2 and 3 connections without removal of insulation by examining the accessible and exposed surfaces and joints of the insulation. Leakage monitoring inside containment at Seabrook Unit 1 is provided by the reactor cavity (containment) drainage sump level monitoring system. This system has high level and alert status alarms in the control room. This system has Tech Spec required monitoring (TS 3/4.4.6.1(b)) at least once every 24 hours. All preservice and inservice examinations were performed by personnel certified in accordance with IWA-2300 of 2004 Edition with No Addenda of the ASME Section XI Code. UT examinations of the austenitic piping welds utilized equipment, procedures, and personnel qualified in accordance with ASME Section XI, Appendix VIII, Supplement 2, 2004 Edition with No Addenda and the Performance Demonstration Initiative (POI) program. The UT techniques for each weld were reviewed to determine if additional coverage could be achieved. Seabrook's procedures require the examiner to make an attempt to achieve complete coverage by using alternative techniques such as using a smaller wedge thus reducing the distance from the exit point to the front of the wedge, changing angles or reducing the search unit element size. Any alternative equipment is required to follow the limits specified in the qualified procedure. Alternate techniques were investigated at the time of discovery. For piping welds performed in accordance with Appendix VIII, Supplement 2, the coverage credited is limited when access can only be obtained from one side. No coverage is claimed
Enclosure 1 SBK-L-21083 Page 5 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS past the centerline in the coverage credited in the Table since access for scanning was not available from that side of the weld and the Performance Demonstration Qualification Summary (PDQS) for the qualified procedure, PDl-UT-2, states that "the austenitic single side qualification documented on this summary demonstrates application of best available technology, but do not meet the requirements of 10CFR 50.55a(b)(2)(xvi)(B)." It should be noted that UT was performed through the weld to obtain the maximum possible Code examination volume and, as shown in the figures, the theoretical beam path extends into the far side for the examinations performed. While the coverage is not included in the Table, the techniques employed for the single side examination are noted in the figures, when applicable and provided for a best effort examination. The coverage obtained was the maximum practical. Therefore, the UT examinations conducted using the Appendix VIII, Supplement 2, qualified procedure provide reasonable assurance for the detection of flaws on the far side of welds where the ultrasonic beam has been transmitted even though not presently qualified. The piping welds listed in Table 1 did not require a surface exam per Seabrook's Risk Informed Program. The volumetric examinations of all the items listed did not reveal any recordable or reportable flaws in the examination zone or adjacent to any volumetric limitations. The extent of examination volumes achieved via volumetric examinations, combined with the system pressure tests and system walk downs, provide assurance of an acceptable level of quality and safety.
7. Duration of Proposed Alternative
This relief request is applicable to the Seabrook Unit 1 Third lnservice Inspection Interval which began August 19, 2010 and ended August 18, 2020.
8. Precedents
Similar relief requests have been granted to the following plants: Seabrook Generating Station, Unit No.1 - Issuance of Relief Requests 21R-20 Regarding Second 10-Year Interval lnservice Inspection Program Plan for Risk Informed Welds (TAC. Nos. ME6901, ML12145A170), dated June 4, 2012. Turkey Point Nuclear Station, Unit Nos.3 & 4- Issuance of Relief Requests RR#16 Regarding Fourth 10-Yearlnterval lnservice Inspection Program Plan for Risk Informed Welds, Class 2 piping Welds and Class 1 & 2 Vessel Welds (TAC. Nos. MF5796, ML15350A203), dated December 3, 2015.
Enclosure 1 SBK-L-21083 Page 6 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS
- 9. References 10CFR50.55a ASME Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components," 2004 Edition with No Addenda ASME Section XI, Division 1, Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds, Section XI, Division 1"
Enclosure 1 SBK-L-21083 Page 7 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System ComponentlD Impracticality of of Requirement and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Valve to Pipe cs 0366-02 04 2014 Exam Category R-A 45°S 1 lnservice examination N/A (3"-160) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access due to reducer (Class 1) configuration. SA376, TP316 Examination pipe side complete. Total coverage: 50.0% Best Effort Far Side: 41 % No Service Flaws were detected Pipe to Valve cs 0368-02 04 2012 Exam Category R-A 45°S 2 lnservice examination N/A (3"-160) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access due to valve (Class 1) configuration. SA376, TP316 Examination pipe side complete. Total coverage: 50.0% Best Effort Far Side: 41 % No Service Flaws were detected
Enclosure 1 SBK-L-21083 Page 8 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table.1 System Year Applicable Code Examination Surface System Component ID Impracticality of of Requirement and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance
*Exam Credit Wave Mode Results Material Pipe to Elbow RC 0097-01 09 2018 Exam Category R-A 45°S 3 lnservice examination N/A (3"-160) Item No. R1.20 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access on pipe for 2.5" (Class 1) due to the intrados elbow SA376, TP316 configuration.
Examination pipe side Total coverage: 89.4% complete. No Service Flaws were detected Elbow to Pipe RC 0097-01 10 2018 Exam Category R-A 45°S 3 lnservice examination N/A (3"-160) Item No. R1.20 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access on pipe for 2.5" (Class 1) due to the intrados elbow SA376, TP316 configuration. Examination pipe side Total coverage: 89.4% complete. No Service Flaws were detected
Enclosure 1 SBK-L-21083 Page 9 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System Component ID Impracticality of of Requirement and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Reducer to RC 0048-03 01 2012 Exam Category R-A 45°S 4 lnservice examination N/A Pipe (4"-160) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to reducer (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Pipe to RH 0160-06 08 2017 Exam Category R-A 45°S 5 lnservice examination N/A Reducer (6"-160) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access due to reducer (Class 1) 60°RL configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected
Enclosure 1 SBK-L-21083 Page 10 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System Component ID Impracticality of of Requirement .and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Pipe to RH 0180-03 08 2012 Exam Category R-A 45°S 5 lnservice examination N/A Reducer (6"-160) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 70°S access due to reducer (Class 1) 60°RL configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Pipe to Valve SI 0251-07 04 2012 Exam Category R-A 45°S 6 lnservice examination N/A (6"-160) Item No. R1.16 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to valve (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected
Enclosure 1 SBK-L-21083 Page 11 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System ComponenflD Impracticality of of Requirement and Coverage Angle and Fig~***. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Valve to Pipe SI 0251-07 05 2012 Exam Category R-A 45°S 6 lnservice examination N/A (6"-160) Item No. R 1.20 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to valve (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Valve to Pipe SI 0201-02 17 2015 Exam Category R-A 45°S 7 lnservice examination N/A (10"-140) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to valve (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected
Enclosure 1 SBK-L-21083 Page 12 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System Component ID .* Impracticality of of Requirement and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Pipe to SI 0201-02 18 2015 Exam Category R-A 45°S 8 lnservice examination NIA Nozzle (10"-140) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to nozzle (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Valve to Pipe SI 0202-02 17 2017 Exam Category R-A 45°S 9 lnservice examination NIA (10"-140) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to valve (Class 1) configuration. SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected
Enclosure 1 SBK-L-21083 Page 13 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System *. Year Applicable Code Examination Surface System Component ID Impracticality of of Requirement and Coverage Angle and Fig. Examination Configuration Diameter-Schedule Compliance Exam Credit Wave Mode Results Material Valve to Pipe SI 0203-02 21 2017 Exam Category R-A 45cs 10 lnservice examination N/A (10"-140) Item No. R 1.11 socs limited to single side Stainless Steel Fig. IWB-2500-8 SOcRL access due to valve (Class 1) configuration. SA37S, TP31S Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Valve to Pipe SI 0204-02 21 2020 Exam Category R-A 45cs 11 lnservice examination N/A (10"-140) Item No. R1.11 socs limited to single side Stainless Steel Fig. IWB-2500-8 70cs access due to valve (Class 1) SOcRL configuration. SA37S, TP31S Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected
Enclosure 1 SBK-L-21083 Page 14 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Table 1 System Year Applicable Code Examination Surface System Component 1.D
- of Impracticality of Requirement and Coverage Angle and Fig. Examination Configuration Diameter~Schedule Compliance 1 Exam Credit Wave Mode Results Material Pipe to Tee RH 0160-17 02 2017 Exam Category R-A 45°S 12 lnservice examination N/A (12"-140) Item No. R1.11 60°S limited to single side Stainless Steel Fig. IWB-2500-8 60°RL access due to tee (Class 1) configuration.
SA376, TP316 Examination pipe side complete. 50.0% Best Effort Far Side No Service Flaws were See Figure detected Pipe to Elbow RC 0013-01 04 2015 Exam Category R-A 45°S 13 lnservice examination N/A (12"-140) Item No. R1.11 60°S limited for all scans 4" of Stainless Steel Fig. IWB-2500-8 40" total scan area due to (Class 1) structural steel that could SA376, TP316 not be removed. Total coverage: 90.0% No Service Flaws were detected
Enclosure 1 SBK-L-21083 Page 15 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Exam coverage: ~est effort far side coverage Near side Axial = 100% 100(0.0457 / 0.1107)= 41% Near side CW= 100% Near side CCW = 100% 300/ 3=100% Far side coverage= 0% ar side weld volume 0.1107 sq/in. Total coverage: 100 I 2 = 50% Coverage Near side weld Far side best effort = 41 %
~-~overage= l 00%
il!ll1 CW & CCW from weld crown & skewed) r 0
\C Pipe 0
Flow '-.,, 0 1 2 3 4 5 6 I I I I I I' I I I I I I I I I I I I' I I I ' ' I I I I I I I I I I I I I l I I t I I I I I I I I I I I I I I I I I I I cs 0366-02 04 (Relief submitted in 2nd interval for this Configuration) Figure 1
Enclosure 1 SBK-L-21083 Page 16 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION O LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Exam coverage: ~est effort far side coverage Near side Axial = 100% 100(0.0457 I 0.1107)= 41% Near side CW= 100% Near side CCW = 100% 300/3=100% Far side coverage= 00/o ~ar side weld volume 0.1107 sq/in. Total coverage: 100 / 2 = 500/o Coverage Near side weld Far side best effort= 41 %
~~~r:~~~~m weld crown & skewed) r 0
\I:?
0 _Pl-PE_ _ ~* VM.VE
/Flow 0 1 2 3 4 5 6 I I I f I I I I I I I I I I I I I I I ! I I I I ' I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I cs 0368-02 04 (Relief submitted in 2nd interval for this Configuration)
Figure 2
Enclosure 1 SBK-L-21083 Page 17 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS II I L.,_.,1¥0 r.v.r ,....
\ C.~*
\
1c~ FILO'"\ -.ftl.. *.. 1.1" *AflOX lc..voa.c ~ 1ti..... --t.1. .., 5oj( , 11,71' oG ~M. "~~C:_Ci'>vde e..,.100.%
- 7J."1X~HR:~cttJ./P""~
, l:&.'3/. #' tl,f.;,P. *w,.c ~ !, $'01. c 10.?i( DF ~ ... 0 \}~tc 011~ e:tAM1..JA11ttu ~ o~~~~ O,.'-IA RC 0097-01 09 (Pipe to Elbow) RC 0097-01 10 (Elbow to Pipe) Figure 3
Enclosure 1 SBK-L-21083 Page 18 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION O LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Far side coverage = 0%
~ Best effort with 60 RL = 100%
Total coverage= Near side coverage= 100% ~ 100+0=100 100 /2 = 50%
;n
~ ~
t"-- ('I
~ \C!
""=
45° 45° 60°L Reducer Pipe 0 RC 0048-03 01
/Flow 0 1 2 3 4 5 6 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Ii I I I I I I I I I I I I I I I I RC 0048-03 01 (Relief submitted in 2nd interval for this Configuration)
Figure 4
Enclosure 1 SBK-L-21083 Page 19 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Total Coverage Credited: 50% Single Side Access RH 0160-06 08 (Pipe to Reducer) RH 0180-03 08 (Reducer to Pipe) (Relief submitted in 2nct interval similar to this Configuration) Figure 5
Enclosure 1 SBK-L-21083 Page 20 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION O LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS VALVE l+---++-0.25'
!131
------ ---- __i RISK INFORMED ISi EXAMINATION VOWl.IE IIHCLUOSll ASUE EXAM VOWMEJ
~ PORTION OF REQUIRO EXAM VOLUMe COVEREll WllH APPENDIX vm QUAUFIEOTECHNIOUES Ill PORTIO!l Of REOUlRED EXAMVOl.UME WHEAE NO CQVliRAG& CREll!l' IS CUJMEO REGARDLESS IF PLOTS INDICATED OTHERWISE Total Coverage Credited: 50%
Single Side Access SI 0251-07 04 (Pipe to Valve) SI 0251-07 05 (Valve to Pipe) (Relief submitted in 2nd interval for this Configuration) Figure 6
Enclosure 1 SBK-L-21083 Page 21 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION O LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS Flo tAJ VALVE. ::: 5" "f>;tf.i;_
<t l). t"\
0
- r 0
y 0 ILi
~
~ :::r Total Coverage Credited: 50%
Single Side Access SI 0201-02 17 (Relief submitted in 2nd interval similar to this Configuration) Figure 7
Enclosure 1 SBK-L-21083 Page 22 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS
\JJC.W::.. 1.~ \\
WL :::. 3~,5\\ FLOW
--..9 0-6 Total Coverage Credited: 50%
Single Side Access SI 0201-02 18 Figure 8
Enclosure 1 SBK-L-21083 Page 23 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION O LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS
\,JC:.W : 1.30
SI C>Z.oz-02 11 We lei k'ih t 3C.. -Sb" I"~
,. , I I I I Total Coverage Credited: 50%
Single Side Access SI 0202-02 17 (Relief submitted in 2nd interval for this Configuration) Figure 9
Enclosure 1 SBK-L-21083 Page 24 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS
-SI OZo3-oz. z l
[1-ow Total Coverage Credited: 50% Single Side Access SI 0203-02 21 (Relief submitted in 2nd interval similar to this Configuration) Figure 10
Enclosure 1 SBK-L-21083 Page 25 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS FLOW ' 0
'O 0 0 9.
QO QI) tr <r 0 6
~f 0
.,bl.
~
Mldt kwth =33. io Total Coverage Credited: 50% Single Side Access SI 0204-02 21 (Relief submitted in 2nd interval similar to this Configuration) Figure 11
Enclosure 1 SBK-L-21083 Page 26 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS \.JG\,..\.: \.Z" W.i:td. ~~" LtC> *'S I I I RH 0160-17 02 Figure 12
Enclosure 1 SBK-L-21083 Page 27 of 27 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-18, REVISION 0 LIMITED COVERAGE OBTAINED FOR PIPING EXAMINATIONS we.w -/. 4 Wl-
- r-/o "
Comments: RC 0013-01 04 Figure 13
Enclosure 2 to SBK-L-21083 Relief Request Number 3IR-19 Relief Request 3IR-19, Limited Coverage Obtained for Class 1 & 2 Vessel Welds Examinations
Enclosure 2 SBK-L-21083 Page 1 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Relief Request In Accordance with 10 CFR50.55a(g(5)iii)
--lnservice Inspection lmpracticality--
- 1. ASME Code Component(s) Affected Class 1 and 2 pressure retaining welds in vessel and piping
- 2. Applicable Code Edition and Addenda The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Rules for lnservice Inspection of Nuclear Power Plant Components, Section XI, 2004 Edition with No Addenda as amended by 10CFR50.55a, is the code of record for the Seabrook Unit 1, 3rd 10-year interval.
- 3. Applicable Code Requirement Steam Generator Head to Tubesheet Weld. *Essentially 100%
8-8 82.40 volumetric examination of the weld length. 8-D 81.10 Pressurizer Nozzle-to-Shell Weld. *Essentially 100% volumetric examination of the weld length. C-A C1.30 Heat Exchanger Tubesheet-to Shell Weld. *Essentially 100% volumetric examination of the weld length. C-8 C2.21 Nozzle -to-Shell Weld. *Essentially 100% volumetric examination of the weld length. As defined by ASME Code Case N-460, essentially 100% means more than 90% of the examination volume of each weld where reduction in coverage is due to interference by another component or part geometry.
- 4. Impracticality of Compliance Due to the configuration, it is not possible to meet the examination coverage requirements of the ASME Code, Section XI, 2004 Edition with No Addenda, as clarified by Code Case N-460. Relief is requested in accordance with 10CFR50.55a(g)(5)(iii). These areas were found during the 3rd 10-year inservice inspection interval.
Enclosure 2 SBK-L-21083 Page 2 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS When a component has conditions, which limit the examination volume, NextEra Energy is required to submit the information to the enforcement and regulatory authorities having jurisdiction at the plant site. This Relief Request has been written to address areas where those types of conditions exist, and the required amount of coverage was reduced below the minimum acceptable. When examined, the welds listed within this request did not receive the required code volume coverage due to their configuration and/or the presence of permanent attachments. These scanning limitations prohibit essentially 100% ultrasonic examination coverage of the required examination volume. Table 1, included in this Relief Request, summarizes the percent of coverage credited and references specific figures that show the extent of coverage. Relief is requested from the ASME Boiler and Pressure Vessel Code required volume as identified in Figure IWB-2500-6, IWB-2500-7, IWC-2500-2, and IWC-2500-4.
- 5. Burden Caused by Compliance Steam Generator Head-to-Tubesheet Weld RC E-11A (Seam 1)
To increase examination coverage on the steam generator heat exchanger head - to-tubesheet weld, removal of the four (4) permanently pedestal welded support attachments that are part of the original heat exchanger design or replacement of the heat exchanger with a design that would allow for complete examination coverage of the subject weld would be required. These options to meet the 100% percent examination coverage requirement are considered impractical. Pressurizer Nozzle-to-Shell-Welds The pressurizer nozzle-to shell welds were examined with a manual ultrasonic technique using most recent technology available to achieve maximum examination coverage practical. Examination coverage of the nozzle-to- shell welds is limited because of single sided access due to nozzle-to-shell weld configuration. The ability to meet the 100 percent examination coverage requirement are considered impractical. Containment Building Spray Heat Exchanger Tubesheet Weld CBS E-16B 01 To increase examination coverage on the CBS heat exchanger tubesheet-to-shell weld, removal of the permanently welded support gusset plates that are part of the original heat exchanger design or replacement of the heat exchanger with a design that would allow for complete examination coverage of the subject weld would be required. These options to meet the 100% percent examination coverage requirement are considered impractical.
Enclosure 2 SBK-L-21083 Page 3 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Containment Building Spray Heat Exchanger The "B" Containment Building Spray (CBS) heat exchanger inlet and outlet nozzle-to-shell welds were examined with a manual ultrasonic technique using most recent technology available to achieve maximum examination coverage practical. Examination coverage of the inlet and outlet nozzle-to- shell welds is limited because of single sided access due to nozzle-to-shell weld configuration. The ability to meet the 100% percent examination coverage requirement are considered impractical. It is not possible to obtain ultrasonic interrogation of greater than 90% of the required examination volume due to interference caused by configuration and/or permanent attachments. Examinations are performed to the maximum extent possible. The Ultrasonic (UT) techniques for each weld were reviewed to determine if additional coverage could be achieved. For the welds listed in Table 1, NextEra Energy determined that removal of the obstruction was not possible without significant work, increased radiation exposure, and/or damage to the plant. Additional weld preparation by welding or metal removal is a modification of the examination area requiring significant engineering and construction personnel support.
- 6. Proposed Alternative and Basis for Use Proposed Alternative
- 1) Periodic system pressure tests in accordance with ASME Section XI Category B-P, Table IWB-2500-1 and C-H, Table IWC-2500-1.
- 2) Conduct ultrasonic examinations to the maximum extent possible.
- 3) Regular walkdowns by operations personnel and system engineers are performed on systems outside containment to check for leakage, piping configuration, and/or damage. During outages, system engineers walkdown systems inside and outside containment. This walkdown is performed to look for system anomalies that could affect plant performance.
Basis The attached Table provides the percent of coverage credited and references specific figures that illustrate the extent of coverage for each weld. The examination figures of ASME Section XI, 2004 Edition with No Addenda, define the examination volume required. The system, diameter, pipe schedule and material are identified for each item within the Table. The angles, Ultrasonic wave modes (Shear-S or Longitudinal-L) that were employed for examination and impracticality of compliance are listed for each weld. Arrows and lines on the figures illustrate the UT transducer beam direction and extent of the area examined.
Enclosure 2 SBK-L-21083 Page 4 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS 10 CFR 50.55a(g)(4) recognizes that throughout the service life of a nuclear power facility, components which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements set forth in the ASME Code to the extent practical within the limitations of design, geometry and materials of construction of the components. Seabrook performed the examinations to the maximum extent possible. There is no plant-specific, NextEra fleet or industry operating experience regarding potential degradation specific to the subject welds included in this relief request. However, isolated occurrences of stress corrosion cracking have occurred in stainless steel materials in the industry. To address the concerns of these isolated cases, periodic walkdowns by plant personnel provide assurance that any isolated degradation would be identified at the onset before a safety concern could develop. The Class 1 and 2 items identified in Table 1 are located within either the reactor containment building or reactor auxiliary building. Regular walkdowns by operations personnel and system engineers are performed on systems in the reactor auxiliary building to check for leakage, piping configuration, and/or damage. During outages, system engineers perform boric acid walkdowns of all systems inside containment. This walkdown is performed to look for borated system as well as system abnormalities that could affect plant performance. Also, a system pressure test and VT-2 visual examination is performed each refueling outage for Class 1 connections and each period for Class 2 and 3 connections without removal of insulation by examining the accessible and exposed surfaces and joints of the insulation. Leakage monitoring inside containment at Seabrook Unit 1 is provided by the reactor cavity (containment) drainage sump level monitoring system. This system has high level and alert status alarms in the control room. This system has Tech Spec required monitoring (TS 3/4.4.6.1 (b)) at least once every 24 hours. All inservice examinations were performed by personnel certified in accordance with IWA-2300 of 2004 Edition with No Addenda of the ASME Section XI Code. UT examinations of the austenitic piping welds utilized equipment, procedures. The ultrasonic procedure utilized met the requirements of ASME Code, Section XI, Appendix I and Appendix 111 as required. The UT techniques for each weld were reviewed to determine if additional coverage could be achieved. Seabrook's procedures require the examiner to make an attempt to achieve complete coverage by using alternative techniques such as using a smaller wedge thus reducing the distance from the exit point to the front of the wedge, changing angles or reducing the search unit element size. Any alternative equipment is required to follow the limits specified in the qualified procedure. Alternate techniques were investigated at the time of discovery.
Enclosure 2 SBK-L-21083 Page 5 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Steam Generator Head-to-Tubesheet Weld RC E-11A (Seam 1) The ASME Code required volume for this item is as required by the ASME B&PV Code, Section XI, Figure IWB-2500-6. As required by ASME Section XI, Table IWB-2500-1, Category B-B Item 2.40, requires this weld be examined volumetrically for essentially 100% of the weld length. Weld RC E11A SEAM-I cannot be examined for essentially 100% of the weld length due to design (physical obstruction from four steam generator supports). ISi Drawing 1-NHY-650011 shows the four steam generator support pads. These pads are approximately 18" in length and block access to this weld in four locations. These obstructions limit the weld examination volume to 82.4%. This was the maximum extent achievable. Pressurizer Nozzle-to-Shell-Welds (RC E-10 A-NZ, RC E-10 B-NZ, RC E-10 C-NZ. RC E-10 D-NZ. RC E-10 SP-NZ. RC E-10 S-NZ) The ASME Code required volume for this item is as required by the ASME B&PV Code, Section XI, Figure IWB-2500-7. As required by ASME Section XI, Table IWB-2500-1, Category B-D Item B 1.10, these welds receive a volumetric examination. The pressurizer nozzle welds RC E-10 A-NZ, RC E-10 B-NZ, RC E-10 C-NZ, RC E-10 D-NZ, RC E-10 SP-NZ, RC E-10 S-NZ have limited coverage due to the nozzle to shell geometry. ISi drawing 1-NHY-650006 shows typical Pressurizer nozzle to stainless steel safe-end weld detail. The transition, from the carbon steel vessel nozzle to the stainless-steel safe-end to the stainless-steel pipe, is large over a short distance. This causes transducer sound beam propagation angle to change abruptly thereby not fully interrogating the required ASME examination volume. Each nozzle has its own unique fit-up, weld, and finish contour which presents specific individual limitations on examination volume. Grinding these transitions or adding weld material to increase examination volume could decrease the level of quality and safety in the Pressurizer nozzle safe-end welds. As depicted in Table 1, these limitations result in coverage from 71 % to 77.5% of the total examination volume. This was the maximum extent achievable. Containment Building Spray Heat Exchanger Tubesheet Weld CBS E-16B 01 The ASME Code-required volume for this item as required by the ASME B&PV Code, Section XI, Figure IWC-2500-2. This figure depicts the examination volume requirements for IWC, Category C-A, Item C1 .30, respectively. As illustrated in Figure IWC-2500-2 the required examination volume includes the entire thickness of the weld and base material, including one half inch (0.50") of the adjacent base material on both sides of the weld. CBS E-16B 01 is limitation on the flange side but it is also limited along the length of the weld on the near side due to attachment welds for the heat exchanger support. The near side limitation for CBS E-16B 01 is 60.25-inches of the 101-inches of circumferential length or approximately 60% of the weld length. As depicted in Table 1, these limitations result in coverage of 20% of the total examination volume. This was the maximum extent achievable.
Enclosure 2 SBK-L-21083 Page 6 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS The specific technology included conventional, composite, and monolithic ultrasonic search units using shear and longitudinal wave modes. The techniques utilized angles, modes, and frequencies that are equivalent to the techniques required by the industry generic procedure for the manual "Ultrasonic Examination of Austenitic Piping Welds," PDl-UT-2. This is an ASME Code, Section XI, Appendix VIII, Supplement 2 qualified procedure for the detection of circumferential and axial flaws in austenitic piping welds when dual side access is available or if the flaw is located on the near side of a single side access configuration. NextEra believes that the equipment and techniques used represent the most recent technology capable of maximizing volumetric coverage of the welds listed in this relief. The ultrasonic procedure utilized met the requirements of ASME Code, Section XI, Appendix I and Appendix Ill as required. The ultrasonic procedure included equivalent techniques and equipment that are also specified for the inspection of the near and far side of welds from an Appendix VIII qualified industry generic procedure for austenitic piping welds, PDl-UT-2. The scope of PDl-UT-2 does not cover austenitic pressure vessel welds. However, the techniques in PDl-UT-2 are applicable due to the similar base and weld materials used for fabrication of weld CBS E-16B 01. The techniques in PDl-UT-2 are not qualified to detect flaws that are on the far side of the weld when access is limited to a single side. However, PDl-UT-2 does provide guidance to perform a "best effort" examination of the far side examination volume. The guidance provided in PDl-UT-2 for the detection of flaws on the far side of the weld is separated into two approaches based upon the thickness of the component being examined. The procedure utilized for examinations of weld CBS E-16B 01 is not required to be ASME Appendix VIII qualified. There is also no requirement for personnel and equipment to be Appendix VI 11 qualified. However, the ultrasonic instruments, search units, and techniques used for these examinations have all previously been successfully qualified by demonstration in accordance with the requirements of ASME Section XI, Appendix VIII, Supplement 2 using the industry generic procedure for the Examination of Austenitic Piping Welds, PDl-UT-2. Additionally, personnel performing examinations were qualified by demonstration in accordance with the requirements of ASME Section XI, Appendix VIII, Supplement 2 as implemented by the PDA. NextEra believes that the equipment, techniques, and examination personnel used provide reasonable assurance that service induced flaws would have been identified in the areas covered.
Enclosure 2 SBK-L-21083 Page 7 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Containment Building Spray Nozzle-to-Shell Weld CBS E-16B Noz 1 and CBS E-16B Noz 2 The ASME Code required volume for this item is as required by the ASME B&PV Code, Section XI, Figure IWC-2500-4. This figure depicts the examination volume requirements for IWC, Category C-B, Item C2.21. As illustrated in Figures IWC- 2500-4, the required examination volume includes the inner 1/3 of the weld and base material thickness, including one quarter inch (0.25") of the adjacent base material on both sides of the weld. As depicted in Table 1, these limitations result in coverage of 50% of the total examination volume due only to the geometry of the weld joint and cannot be adequately examined from the opposite side of the weld due to the nozzle
-to-shell configuration. This was the maximum extent achievable.
Equipment, procedure, and personnel requirements are the same as discussed within the basis of the CBS E-16B 01 tubesheet to shell weld above. For steam generator weld RC E-11A Seam 1 and pressurizer nozzle to shell welds RC E-10 A-NZ, RC E-10 B-NZ, RC E-10 C-NZ, RC E-10 D-NZ, RC-E-10 SP-N, RC E-10 S-NZ and Containment Spray Heat Exchanger weld CBS E-16B 01, listed in Table 1, surface examinations were not required. Welds CBS E-16B N1 and CBS E-16B N2 are Class 2 Category C-B nozzle to shell welds, which require surface examinations per ASME Code Category C-B, Item No. C2.21. The surface and volumetric examinations of all the items listed did not reveal any recordable or reportable flaws in the examination zone or adjacent to any volumetric limitations. The extent of examination volumes achieved via surface and/or volumetric examinations, combined with the system pressure tests and system walk downs, provide assurance of an acceptable level of quality and safety. In all cases, 100% of the accessible Code required surface area was examined. All welds had a surface examination (liquid penetrant) and radiographic (RT) performed and were acceptable for service prior to initial startup.
- 7. Duration of Proposed Alternative This relief request is applicable to the Seabrook unit 1 Third lnservice Inspection Interval which began August 19, 2010 and ended August 18, 2020.
Enclosure 2 SBK-L-21083 Page 8 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS
- 8. Precedents Similar relief requests have been granted to the following plants:
Seabrook Generating Station, Unit No.1 - Issuance of Relief Requests 21R-17 Regarding Second 10-Yearlnterval lnservice Inspection Program Plan for Category C-A Item C1.30 Welds (TAC. Nos. ME6904, ML12144A240), dated June 4, 2012. Seabrook Generating Station, Unit No.1 - Issuance of Relief Requests 21R-18 Regarding Second 10-Yearlnterval lnservice Inspection Program Plan for Category C-B Item C2.21 Welds (TAC. Nos. ME6903, ML12144A435), dated June 4, 2012. Seabrook Generating Station, Unit No.1 - Issuance of Relief Requests 21R-2 Regarding Second 10-Year Interval lnservice Inspection Program Plan for Category B-B Item C2.40 Welds (TAC. Nos. MA9902, ML ML010540162), dated March 21, 2001. Turkey Point Nuclear Station, Unit Nos.3 & 4- Issuance of Relief Requests RR#16 Regarding Fourth 10-Year Interval lnservice Inspection Program Plan for Risk Informed Welds, Class 2 piping Welds and Class 1 & 2 Vessel Welds (TAC. Nos. MF5796, ML15350A203), dated December 3, 2015.
- 8. References 10CFR50.55a ASME Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components,"
2004 Edition with No Addenda. ASME Section XI, Division 1, Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds, Section XI, Division 1"
Enclosure 2 SBK-L-21083 Page 9 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Systern** Applicable Code Surface
**. ComponentlD Requirement and Fig. Examination
** Diarlieter:.schedule coverage Credit Results Material Tube sheet to A Steam Generator 2017 Exam Category 8-8 45°S 1 lnservice examination N/A Head Weld RC E-11A SEAM-1 Item No. 82.40 60°S limited in 4 areas both due Carbon Steel Clad Fig. IW8-2500-6 steam generator pedestal lug configuration I I Total Coverage: 82.4%
Nozzle to Safety Nozzle 2014 Exam Category 8-D 45°S 2 lnservice examination N/A Shell Weld RC E-10 A-NZ Item No. 83.110 60°S limited due nozzle-to-shell Carbon Steel Clad Fig. IW8-2500-7(8) weld configuration. SA533 GR. A CL.2 I I No service induced flaws Total Coverage: 74.0% were identified. I Nozzle to Safety Nozzle 2018 Exam Category 8-D 45°S 3 lnservice examination I N/A Shell Weld I RC E-10 8-NZ Item No. 83.110 60°S limited due nozzle-to-shell Carbon Steel Clad Fig. IW8-2500-7(8) weld configuration. SA533 GR. A CL.2 No service induced flaws Total Coverage: 71.7% were identified.
Enclosure 2 SBK-L-21083 Page 10 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS
**** i .* s~~~g~~~tiio<:*/***.****
. biameter;;Scheaule
- Matedar*
lnservice examination Nozzle to Safety Nozzle 2012 Exam Category 8-D 45°S 3 limited due nozzle-to-shell I N/A Shell Weld RC E-10 C-NZ Item No. 83.110 60°S weld configuration. Carbon Steel Clad Fig. IW8-2500-7(8) I No service induced flaws SA533 GR. A CL.2 I I I were identified. Total Coverage: 71.7% Nozzle to Safety Nozzle 2018 Exam Category 8-D 45°S 3 lnservice examination I N/A Shell Weld RC E-10 D-NZ Item No. 83.110 60°S limited due nozzle-to-shell Carbon Steel Clad Fig. IW8-2500-7(8) weld configuration. SA533 GR. A CL.2 No service induced flaws Total Coverage: 71.7% were identified. Nozzle to Spray Nozzle 2012 Exam Category 8-D 45°S 4 lnservice examination N/A Shell Weld RC E-10 SP-NZ Item No. 83.110 60°S limited due nozzle-to-shell Carbon Steel Clad Fig. IW8-2500-7(8) weld configuration. SA533 GR. A CL.2 No service induced flaws Total Coverage: 77.5% were identified.
Enclosure 2 SBK-L-21083 Page 11 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS
- @<~.riJin~tibn I'[
Angleand*
- Wave.Mode Nozzle to Surge Nozzle 2018 Exam Category 8-D 45°S 5 Inservice examination N/A Shell Weld RC E-10 S-NZ Item No. 83.110 60°S limited due pressurizer Carbon Steel Clad Fig. IW8-2500-7(8) heater obstruction and nozzle-to-shell weld SA533 GR. A CL.2 configuration.
Total Coverage: 71.0% No service induced flaws were identified. Tube sheet to Containment Spray 2020 Exam Category C-A 45°S 6 Inservice examination N/A Shell Weld Heat Exchanger Item No. C1 .30 60°L 7 limited for 60.25" of 101" CBS E-168 01 Fig. IWC-2500-2 due to welded attachment on heat exchanger and 3" on shell side due to SA240TP304 instrumentation line. Total scan area from shell side was 40.50" due to nozzle configuration. Total Coverage: 20.0% No service induced flaws were identified.
Enclosure 2 SBK-L-21083 Page 12 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Applicabl~**Cod.e E:i(amination
*** Requiretnentand .Angle and' Coverage*Credit Wave Mode Nozzle to Containment Spray 2020 Exam Category C-8 45°S 8 lnservice examination 100% complete.
Shell Weld Heat Exchanger Item No. C2.21 60°L 9 limited due nozzle-to-shell No service CBS E-168 N1 Fig. IWC-2500-4(8) weld configuration. Exam induced flaws. from shell side is complete. Shell - SA240 TP304 Nozzle - SA312 TP304 No service induced flaws were identified. Total Coverage: 50.0% Nozzle to Containment Spray 2020 Exam Category C-8 45°S 8 lnservice examination 100% complete. Shell Weld Heat Exchanger Item No. C2.21 60°L 9 limited due nozzle-to-shell No service CBS E-168 N2 Fig. IWC-2500-4(8) weld configuration. Exam induced flaws. from shell side is complete Shell - SA240 TP304 Nozzle- SA312 TP304 No service induced flaws were identified. Total Coverage: 50.0%
Enclosure 2 SBK-L-21083 Page 13 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS E:uOilmination VoJumll
------qs*
Tulw. ~hu.t p~
------'II
. I~"~ Z" le-1<!1 Aft!'~ Ml~~ea 01\ llOUi ~Id<!~<'.>! W'1!1ll (!(.,;It:\ f'*l4tf!E:~UI L<!a~
Measurlng 18.0" Wlcle: at 4 Loc.atlon:S- 7:UY' ofUmltatkm B:est Coverage Ac.hlevable: cue to Pe~es.tal Lugs: 7.<l" x .:t.ll" x 409.25" "'Total Volllme l4536.56 7 .J[" J<l.l.ll"' ~ H7.2S" -~ C(>IJM..,d Volum~ 1.Hl79.1:l 11517!J.1l/ lJ!S3f>.S6
- ijJ.401;3'il<\
i'-'Z,Ll"---1 4. ON= !52..41% Cv*t!I dl:lt! CON= 82;4% Co11erage l+D Slde =SZ.4% Cover111ge C.iwinr:1111e TS Side~
- T~t<>I Wcl~I li<>lum<: - (1.J" "~.O'") / 2 J.12 3.11 ~ 409'.25"= lZ7fi.85
~.II' 1276.86 x 2.()" = 2553.72
- TJtal l.imi~ed Weld V.olume= (0.16 x 0..22'"!/ 2 = (l'.017f 0.0176 x 409.25µ =7. 20-28 72028: / 2:553.n-0.:!8% Linit&d Wel-d Voli.!me 4!:i.* 1000G 60"~99.72%
l"'1*&.'l~ Tot,.I TS Sr:di: Vulumi= Cuv.,1asi:: C.C.W* !?.I.\*;. 11979.12-0.0176 "11979.1024 liti~*Ot.* 81..t.t*/. t 1979.10..14J1.4536. 56 .. 82.4057% rs ~1.k* s2.r.r,*k Comm~nt&; O/t/ - 62.4% Co*erage
~ 8 2 .*~% ccr~~rijf!<<'
31Jg_k.LAAh._M;sllc! o,,.._'.Bcitn_~;det; e~ 1h-c. \..l<:ld._ Oue. \Q 1h< thbtcJ ~::.*J7i '- (W lfJ Side= 81.:.4% C:Overage tl'1"~'i,Z."_11 ~'tU'"*_ t<>~L"l,loJ~ l'i~3<..S(. T5 Side "82.4% coverage 1.'t" x ~.e" ic .Jllz.r*" Covtwd lk;l..mc. _!1!i~J.1:...____________ =1
-- ll</7."f,l'Z- -v8Z~-'-I-% 1(>-f.uJfove,-,,!Cf.:
~cm/tArE :rrJ4itt.n~o/531Q. S(p I TUldl CUV!;!< 41K"" a?,*'M RC E-11A SEAM-1 (Relief submitted in 2nd interval for this Configuration) Figure 1
Enclosure 2 SBK-L-21083 Page 14 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Weldmctal=r
~B.aseme1al CW&CCW
- 2. 7435 sqlin T<>tal eXJUtt area
~CW&CCW area 4:4836 *qli ..
I 1.0546 sq/in Base metal e~am area ~ 11.0546 *2.8513= 8.2033 sq/in Weld metal Kadiali:n 2.8217 sq/in an:a' v* g BCIS& motnl 11tco Radin! dir.,otion 7.229sqlin
~ .,,,.j WeJdmetalarea 2.8Sl3 sqlin ' ~
Wcldmetalarca ~ Kadllllout
~ 0.4J'11sql:in
~
Rl.: ll* IUA-NZ (.;overage k f;/j~ @ Weld mc<al (both beam* - both sides) Axial nozzle side 100(1).4377/2.8513) t>i """""~ ;:/ -15.3l1> 60"- I "'- AAi*l 31icll *ille 100(2.827712.6Jl3)
-99.1%
wY c-vJrccw CWJCCW 100(2.7413512.1!513)
=96..2%
Total Weld Metal: 15.3 +99. I +96.2 + 96.2=306.8 306.8 / 4 - 76.7"4 I Base metal (two dill'erent angle. beams) Axial Sbell side I00(7 .229/8.2033)
=88.1%
cw Jccw 100(4.411;36/8.:2033)
=54.6%
Total Weld Metal: 88.I +54.6* 141.'I 142.7/2*71.3% Scale J*:l Total COVCill!!C =76. 7 i* 71.3 = 148 148/2-74% RC E-10 A-NZ (Relief submitted in 2nd interval for this Configuration) Figure 2
Enclosure 2 SBK-L-21083 Page 15 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS
% EXAMINED Tangential Scan (CW) = 90.6%
Tangential Scan (CCW) = 90.6% TOTAL EXAMINATION AREA= -1140 sq. in x 360 deg. (2.9 x 3.9 =11.31 + .09 =11.4 sq in.) Radial Scan (CW45 Shell} = 90.6% The area defined below was missed with the seerch units listed above Area Not Examined
.3 x .6' - .18" .18'" / 2 - .09" with tangential scans or either 46 or 60 ,1.45'" x 1/25" -1.95" 1.95'" / 2 - .978'" perpendicular scans in at least one direction 1.068 sq In.
Not Examined *-_../ Area Examined with 46 and/or 60 in one
!Radial Scan (60 Nz} = 15.1 o/o direction 2.45" x 1.4" =3.43", 3.43" / 2 =1.716" 1.715" / 11.40" =.151or15.1%
286.9 i.<!" asooeo
*- . . i-Area of 2 Bllgle, 2 d1!l!cllon OOWl'lfl1!
2.9"
= 111.12%1 286.9 / 4 Not to scale I+- :ur -4 l
Examination volume (weld+ 112 Teach side) Both ultrasonic beams must pass thru the entte volume of weld metaL The adjacent base material In the exam volume must ba completely scanned vAth two angle beams, but need not be examined by both angle beams from both directions, (any oombinetion of the two angle beams will satisfy the requirement.) RC E-10 8-NZ, RC E-10 C-NZ, RC E-10 D-NZ (Relief submitted in 2nd interval for this Configuration) Figure 3
Enclosure 2 SBK-L-21083 Page 16 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS Tangential Scan (CW) -. 92.5 % Tangential scan (CCW} "' 92.5 % Radial Scan (60 Shell ) = 92.5 % rn. 81'98 defined Mlowwas missed with lhs S$1lroh uni/ii liatod otxive
*T"x-1:1"'*.lr, ,111.n
- JM~tl
- TOTAL EXAMINATION AREA= ..... 13.21 sq. inx360 deg .
..r'llU'"*fr, 1.rl2;;.Kn.l!L.
.tuoqla. Weld Length= 27.0"
~r.~w -2u1qr...01 ... 111....i
-.rn~.u* mu .. 1M11*"""
Area Not examined Radial Scan (45 Noz)"' 32.4% wilh tangential scans and ellller45 or 6Q PeJPsndlcufar in al least one diedioo
~.O"'ll!:).86**e.6$, 8.15"'/2~-4.27aqln.
21'" x 4.27 a 11e.u ¥q 111 oJ*n* oxarin*d t Area where both beams have Hf.ASISIUFo .3238 or31.~'A-"*"'Oll two direotiona4 coverage
-f.1' 309.9 T
309.9/ 4= 111.s % I Area Examined will! 45 and I or 61l in al bast one direction Not to scale
~ 415" Jiii Comment:
Examination volume (weld + 1/2. Teach side) Both ultrasonic beams must pass thru tf\e entire volume of weld metal. The adjacent base material In the exam volume must be completely scanne-l Weld - Axial Coverage from Noz Side Weld - Axial Coverage fom Shell Side Direction (Hatched Areas) Direction 45Deg* 2..2" X1.8" *2.95'" 2.95" 12*1.98&q In,
~
46DeG -100% 60009-76% 1.99"
- 89.5
- 176.23 175.2~ 382.U
- 47.$%
&o oea *2.2"x1.1'"
- 2.42'" 2.42" 12
- 1.21 sq In.
1.21" '88.6
- 107.08 107.081382.U
- 27.9% ~ Weld - Axial Coverage lorn Noz Side Two Direction 4&0eg-100% 800eg-100%
RC E-10 S-NZ (Relief submitted in 2nd interval for this Configuration) Figure 5
Enclosure 2 SBK-L-21083 Page 18 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS L~~
~
~
rn _J
~ WELD VOLUME ll!ill NO EXAMINTION COVERAGE DUE TO CONFIGURATION GEOMETRY ( LIMITATIOl'J)
SECTIONA*A CBS E-168 01 (Relief submitted in 2nd interval for this Configuration) Figure 6
Enclosure 2 SBK-L-21083 Page 19 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS CROSS SECTIONAL VIEW OF OBSTRUCTIONS AT THE SUPPORT.ATTACHMENTS CROSS SECTIONAL VIEW OF OBSTRUCTIONS BETWEEN THE SUPPORT ATTACHMENTS (NO COVERAGE ON EITHER SIDE OF THE Wa.O) ( LIMITED COVERAGE ACHIEVED FROM ONE SIDE OF THE WELD,' r
,.\..td'<P SIJpPQt' ~
Alf<>t)\Mt Of-0"1" ASME REQUIRED / E.JW.41HATION VOlUME I JO"NO COVEAAG; CUE ro WELDED SUPPORT ATTACl1 MENT ,.i.,5* C:BS E*lbB I ( 1e-"1.5 " f '#.11.tl\
,.,_..,, ,, x.
~:* ~ ';,:~~
Ar.,_ "\
~
~ PORTJO/.I OF MME EX>MYOWMEWllERECOVEAAGECAEOIT IO CLAIMED
._,\ ~ ,,:J;..:<,;, A 3.0" l.i~~l-J\ti'l m PORTICN 01' ASM! EXAAI VOi.UM£ WHl!IU! kOCOVEll\llG!CR!OIT IS CLAll£Q RfGAAOLESS IF PLOTS IHOLCATEOOTHERWISE
'r:i:cz:z:o:uu:r old.lb!
h1ppo rl- t All"""""' Connr..;1 11(1: F
~le.-£JeLe1rn.-d.~,-{l.~.,.-a..!i,,,,,_~U;;tJ'lJ~~,Q'._T.,1.,
o-~.eo. = 'lo.:;io ~ l;,.. jh,..j]0"-dve. =lo 1.>e..1&&..illfl>..C.hm.~ ~ (.o.;i,s':
~ ~* ~.t. J~3.- ,,.P~i.__f;J<. AMP.Jf/) l.n
~
.,.,-=-
., ..;.e, SECTION A-A CBS E-168 01 (Relief submitted in 2nd interval for this Configuration)
Figure 7
Enclosure 2 SBK-L-21083 Page 20 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS CBS E-16BN1 CBSE*16BN2
/1\ \
SECTIONA*A CLASS3
/
INLET/OUTLET TYPICAL WELD DETAILS __/ CLASS2 ,.~ Total Coverage: 50% (Single Side Access) h_ [I] f;22j _J WELO VOLUME Im NO EXAMINTION COVERAGE DUE TO CONFIGURATl ON GEOMETRY (LIMITATION) SHtU... CBS E-16B N1 and CBS E-16B N2 (Relief submitted in 2nd interval for this Configuration) Figure 8
Enclosure 2 SBK-L-21083 Page 21 of 21 SEABROOK UNIT 1 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 31R-19, REVISION 0 LIMITED COVERAGE OBTAINED FOR CLASS 1 & 2 VESSEL WELDS EXAMINATIONS CROSS SECTIONAL VIEW OF CONFIGURATION AND EXAMINATION VOLUME (SHOWING BEAM ANGLE COVERAGE ACHEIYEO)
~
il5 ASME REQUIRED EXAMINATION cas HEAT EXCHANGER VOLUME I SECTION A-A INLET /OUTLET TYPICAL CLASS3 WELD DETAILS CLASS2
~
83' _J
~
m PORTIOff OF ASME EXAM VOLUME WHER1i COVERAGE CllEDIT IS CLAIME.O PORTION OF ASME EXAM VOl.UME WHERE NO COVERAGE CREDIT IS CU!MED REGARDLESS IF PLOTS INOICATl!D OTHERWISE CBS E-16B N1 and CBS E-16B N2 (Relief submitted in 2nd interval for this Configuration) Figure 9}}