C4 -7 (U(44L · 2014. 7. 30. · 1 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 Relief Request In Accordance with 10 CFR50.55a(g)(5)(iii)--Inservice

0

FPL.June 30, 2014

L-2014-20810 CFR 50.4

10 CFR 50.55a

U. S. Nuclear Regulatory CommissionAttn: Document Control DeskWashington, DC 20555

Re: St. Lucie Unit 2Docket No. 50-389Inservice Inspection PlanThird Ten-Year Interval Unit 2 Relief Request No. 17

In accordance with 10 CFR 50.55a(g)(5)(iii), inservice inspection impracticality, Florida Power& Light (FPL) requests relief from the examination requirements of the ASME Code, SectionXI, 1998 Edition with Addenda through 2000, as clarified by Code Case N-460, for the subjectASME Code Category B-A welds. The basis for the relief request is provided in theAttachment.

Please contact Ken Frehafer at (772) 467-7748 if there are any questions about this submittal.

Sincerely,

Eric S. KatzmanLicensing ManagerSt. Lucie Plant

Attachment

ESK/KWF

C4 -7(U(44LFlorida Power & Light Company

6501 S. Ocean Drive, Jensen Beach, FL 34957

L-2014-208Attachment

1 of 20St. Lucie Unit 2

THIRD INSPECTION INTERVALRELIEF REQUEST NUMBER 17, REVISION 0

Relief RequestIn Accordance with 10 CFR50.55a(g)(5)(iii)

-- Inservice Inspection Impracticality--

1. ASME Code Component(s) Affected

Class 1 pressure retaining welds in the reactor pressure vessel (RPV).

2. Applicable Code Edition and Addenda

The Code of record for St. Lucie Unit 2 (PSL-2) is the 1998 Edition with Addendathrough 2000 of the ASME Boiler and Pressure Vessel Code, Section Xl, "Rules forInservice Inspection of Nuclear Power Plant Components" as modified by 10CFR50.55a.The 1998 Edition with Addenda through 2000 was utilized for ASME Section XI,Appendix VIII.

3. Applicable Code Requirement

Exam Item No. Examination RequirementsCat.

B1.10 Essentially 100% volumetric examination of allB-A B1.11 longitudinal and circumferential shell welds (does not

B1.12 include shell to flange weld).

B1.20 Essentially 100% volumetric examination of accessibleB1.22 length of circumferential and meridional head welds.

As defined by 10CFR50.55a(g)(6)(ii)(A)(2) and ASME Code Case N-460, essentially100% means more than 90% of the examination volume of each weld where reduction incoverage is due to interference by another component or part geometry.

4. Impracticality of Compliance

Due to the configuration of the Reactor Vessel, it is impractical to meet the examinationcoverage requirements of the ASME Code, Section XI, 1998 Edition with Addendathrough 2000, as clarified by Code Case N-460. Relief is requested in accordance with10 CFR 50.55a(g)(5)(iii). These areas were found during the 3rd 10-year inserviceinspection interval.

When examined, the welds listed within this request did not receive the required codevolume coverage due to their configuration and/or the presence of permanentattachments. These scanning limitations prohibit essentially 100% ultrasonicexamination coverage of the required examination volume.




Described below, coupled with figures, are details of the examination limitations by welddescription. Figure 1 provides an illustration of the contact UT head used for scanningfrom the vessel shell. Figures 2 through 15 provide the dimensions and locations ofobstructions and views of each of the affected welds showing the interference caused bythe permanent attachments on the Trans World System (TWS) robot and the affect ofthe obstructions on scanning.

RPV Intermediate Shell-to-Lower Shell Circumferential Weld (101-171)

Examination Category B-A, Item B1.11

The examination of the Figure IWB-2500-2 A-B-C-D volume is limited due to thesix surveillance capsule holders. Access to approximately 17% of theexamination volume is restricted. The remaining examination volume wasexamined with techniques which have been qualified by demonstration inaccordance with Supplements 4 & 6 of the 1998 Edition with Addenda through2000 of the ASME Code Section Xl, Appendix VIII, using the PerformanceDemonstration Initiative Protocol. This weld was examined from both sides ofthe weld, scanning both parallel and perpendicular. These ultrasonicexaminations did not reveal any recordable or reportable flaws in accordancewith the ASME Code Section Xl, 1998 Edition with Addenda through 2000.

Figure 2 is a view of the TWS robot in the vessel shell region showing scanlimitations caused by the six surveillance capsule holders. The weld is coveredby the six surveillance capsule holders. Figure 3 provides dimensionalinformation for the six surveillance capsule holders and their affect on scanning.Figure 4 is a roll out view showing the reactor vessel inside surface scan areas(cross hatched) and the locations of limited areas due to the presence of the sixsurveillance capsule holders.

RPV Circumferential Bottom Head-to-Lower Shell Weld (201-141)


The examination of the Figure IWB-2500-3 A-B-C-D volume is limited due to theproximity of the Core Barrel Stabilizers and Core Lugs. Access to approximately29% of the examination volume is restricted. The remaining examination volumewas examined with techniques which have been qualified by demonstration inaccordance with Supplements 4 & 6 of the 1998 Edition with Addenda through2000 of the ASME Code Section Xl, Appendix VIII, using the PerformanceDemonstration Initiative Protocol. This weld was examined from both sides ofthe weld, scanning both parallel and perpendicular to the weld. These ultrasonicexaminations did not reveal any recordable or reportable flaws in accordancewith the ASME Code Section XI, 1998 Edition with Addenda through 2000.

Figure 5 is a view of the TWS robot in the vessel shell region showing scanlimitations caused by the Core Barrel Stabilizers and Core Lugs. Figure 6




provides dimensional information for the core barrel stabilizers and core lugs andtheir locations in the reactor vessel. Figure 7 is a roll out view showing thereactor vessel inside surface scan areas (cross hatched) for the bottom head-to-lower shell weld and the locations of limited areas due to the presence of thecore barrel stabilizers and core lugs.

RPV Upper Shell Longitudinal Seam Weld at 15 Degrees (101-122A)


The examination of the Figure IWB-2500-2 A-B-C-D volume is limited due to theoutlet nozzle at zero degrees integral extension. Access to approximately 37%of the examination volume is restricted. The remaining examination volume wasexamined with techniques which have been qualified by demonstration inaccordance with Supplements 4 & 6 of the 1998 Edition with Addenda through2000 of the ASME Code Section XI, Appendix VIII, using the PerformanceDemonstration Initiative Protocol. This weld was examined from both sides ofthe weld, scanning both parallel and perpendicular to the weld. These ultrasonicexaminations did not reveal any recordable or reportable flaws in accordancewith the ASME Code Section Xl, 1998 Edition with Addenda through 2000.

Figures 8 and 9 are views of the TWS robot in the vessel shell region showingthe scan limitation caused by the outlet nozzle at zero degrees integralextension. Figure 10 provides dimensional information and the affect the outletnozzle at zero integral extension had on scanning. Figure 11 is a roll out viewshowing the reactor vessel inside surface scan areas (cross hatched) for theupper shell longitudinal seam weld at 15 degrees.

RPV Lower Head Peel Segment Welds (101-154-A through F)


The examination of the Figure IWB-2500-3 E-F-G-H volume is limited due to theproximity of the flow baffle. Access to approximately 47% of welds 101-154-A,101-154-C, 101-154-E and 57% of welds 101-154-B, 101-154-D, 101-154-Fexamination volume is restricted due to limited access behind the flow baffle.The remaining examination volume was examined with techniques which havebeen qualified by demonstration in accordance with Supplements 4 & 6 of the1998 Edition with Addenda through 2000 of the ASME Code Section XI,Appendix VIII, using the Performance Demonstration Initiative Protocol. Thisweld was examined from both sides of the weld, scanning both parallel andperpendicular to the weld. These ultrasonic examinations did not reveal anyrecordable or reportable flaws in accordance with the ASME Code Section Xl,1998 Edition with Addenda through 2000.Figures 12 and 13 are views of the TWS robot in the vessel shell region showingscan limitations due to limited access behind the flow baffle and core lugs.Figure 14 provides dimensional information for the core lugs and core baffle and




their affect on scanning. Figure 15 is a roll out view showing the reactor vesselinside surface scan areas (cross hatched) for the peel segment welds and thelocations of the core lugs.

5. Burden Caused by Compliance

It is not possible to obtain ultrasonic interrogation of greater than 90% of the requiredexamination volume due to interference caused by configuration and/or permanentattachments. Examinations were performed to the maximum extent possible. For thewelds listed in this relief request, it is not possible to remove the permanently attachedobstructions to increase ASME Code coverage without significant work, increasedradiation exposure, and/or damage to the plant.

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.

Basis

FPL performed inservice examinations of selected welds in accordance with therequirements of 10CFR50.55a, plant technical specifications, and the 1998 Edition withAddenda through 2000, of the American Society of Mechanical Engineers (ASME) Boilerand Pressure Vessel Code, Section Xl. When a component has conditions which limitthe examination volume, Florida Power and Light is required to submit the information tothe enforcement and regulatory authorities having jurisdiction at the plant site. ThisRelief Request has been written to address areas where those types of conditions existand the required amount of coverage was reduced below the minimum acceptable.

FPL performed mechanized ultrasonic examinations of the reactor vessel during the2012 (SL2-20) refueling outage.

10 CFR 50.55a(g)(4) recognizes that throughout the service life of a nuclear powerfacility, components which are classified as ASME Code Class 1, Class 2, and Class 3must meet the requirements set forth in the ASME Code to the extent practical within thelimitations of design, geometry and materials of construction of the components.

The mechanized techniques employed for examination from the RPV inside have beendemonstrated in accordance with Supplements 4 & 6 of the 1998 Edition with Addendathrough 2000 of the ASME Code Section XI, Appendix VIII, using the PerformanceDemonstration Initiative Protocol. The Ultrasonic (UT) techniques for each weld werereviewed to determine if additional coverage could be achieved. Access for examinationof the affected welds from the outside of the reactor vessel is not possible. Access and




permanently installed attachments inside the reactor vessel limit additional scanning ofthe welds included in this request for relief.

In addition to the required ultrasonic examinations, the interior of the reactor vessel,including welded attachments, received visual examination in accordance with TableIWB-2500-1, Examination Categories B-N-i, B-N-2, and B-N-3. Additionally,Examination Category B-D nozzle inner radius examinations were performed inaccordance with ASME Code Case N-648-1, as amended by 10CFR50.55a. With theexception of acceptable visual indications identified at the top of the material surveillancecapsule holders at the 83 and 97 degree azimuths, the visual examinations revealed noindications.

The subject welds were also examined in the second interval during the 10-year reactorvessel examination. The second interval examinations did not reveal any reportableflaws.

The extent of examination volume achieved ultrasonically, the alternate scansperformed, and the system pressure tests provide assurance of an acceptable level ofquality and safety.

7. Duration of Proposed Alternative

This relief request is applicable to the St. Lucie unit 2 Third Inservice Inspection Intervalwhich began August 8, 2003 and ended August 7, 2013.

8. References

10CFR50.55a

ASME Section XI, "Rules For Inservice Inspection of Nuclear Power Plant Components,"1998 Edition with Addenda through 2000

ASME Section Xl, Division 1, Code Case N-460, "Alternative Examination Coverage forClass 1 and Class 2 Welds, Section XI, Division 1"




CONTACT51OCK END

CONTACT HEADD RECTIONAL

ARROW

V

2x3 L,7FOR

HEAD CO\FIGUFRATIONSHELL SCANNING

(AS VyEWED FROM BACK OF ROBOHAND COUPLING)

Illustration of the typical UT head configuration used for vessel shell weld scanning. Overall headdimensions are approximately 12" x 8".

Figure 1




RPV Intermediate Shell-to-Lower Shell Circumferential Weld (101-171)

View of TWS robot in vessel shell region showing scan limitation caused by the surveillance capsuleholders. The weld is covered by the surveillance capsule holders. These limitations occur at twocircumferential locations on this weld at 1800 apart. Single sided scan parameters are used nearobstructions to improve examination coverage. Coverage obtained on this weld is 83%.

Figure 2




270YAND90"

-263, 27'TAND AND

IDELTA -40izsTP(STP w sr)

UIMENS•UNS• SHOUWN IN DLEGIREES

TOTAL SCAN AREA OFYELD 101-171 IS LIMITED DUETO 6 SURVEILLANCE HOLDERS

TOTAL WELD LENGTH= 546.01 INCHES

SHO- SURVEILLANCE HOLDER OBSTRUCTED

RPV Intermediate Shell-to-Lower Shell Circumferential Weld (1 01-171)

Figure 3




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r 1

I!T

~ I:

IRPV Intermediate Shell-to-Lower Shell Circumferential Weld (101-171)

Figure 4




RPV Circumferential Bottom Head-to-Lower Shell Weld (201-141) and Peel Segment Welds(101-154-A through F) Behind Flow Baffle

View of TWS robot in lower vessel shell region showing scan limitations caused by the Core BarrelStabilizers, Core Lugs and the Flow Baffle. The weld examinations are obstructed by these features.Single sided scan parameters are applied as applicable near the obstructions to increase coverage.Coverage on the circumferential weld is 71% and coverage on the peel segment welds is 53% for weldsA, C, and E and 43% for welds B, D, and F.

Figure 5




0.

CORE BARRELSTABIUZER

TYP 6X-

CORE

WELD 201-141

BAFFLE

'CORE LUGTYp 9x


Figure 6




,- o-, ,101-1,4-F 101-154-A 101o154-,

[2.I- 41]


Figure 7




RPV Upper Shell Longitudinal Seam Weld at 15 Degrees (101-122-A)

View of TWS robot in upper vessel nozzle belt region showing scan limitation caused by the outlet nozzlereinforcement. The weld intersects the outlet nozzle and limits UT head movement adjacent to the outletnozzle on both the upper and lower portions of the weld. Single side scan parameters are used on thisweld in the axial beam directions to improve coverage. Coverage obtained on this weld is 63%.

Figure 8





View of TWS robot in upper vessel nozzle belt region showing scan limitation caused by the outlet nozzlereinforcement on the upper portion of the weld. The weld intersects the outlet nozzle and limits UT headmovement adjacent to the outlet nozzle. Single side scan parameters are used on this weld in the axialbeam directions to improve coverage. Coverage obtained on this weld is 63%.

Figure 9




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Figure 10




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101-121 1 - i-- i

rAp rAý rrAtýýI -- I , I , , I , I I , I , , , , , - . . . . .101-122"

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Figure 11




RPV Lower Head Peel Segment Welds (101-154-A through F) Below Flow Baffle

View of TWS robot in lower head below flow baffle showing scan limitation caused by the baffle. The peelsegment welds are covered by the baffle. Single side scan parameters are used on these welds belowthe baffle for the axial beam directions. Coverage on the peel segment welds is 53% for welds A, C, andE and 43% for welds B, D, and F.

Figure 12





View of TWS robot in lower head below flow baffle showing scan limitation caused by the baffle. The peelsegment welds are covered by the baffle. Single side scan parameters are used on these welds belowthe baffle for the axial beam directions. Coverage on the peel segment welds is 53% for welds A, C, andE and 43% for welds B, D, and F.

Figure 13




FLOW


Figure 14




1W 27 1

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201-141 ,


Figure 15

Documents

C4 -7 (U(44L · 2014. 7. 30. · 1 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 Relief Request In Accordance with 10 CFR50.55a(g)(5)(iii)--Inservice