L-2014-208, Third Ten-Year Interval Unit 2 Relief Request No. 17

Third Ten-Year Interval Unit 2 Relief Request No. 17

ML14203A047
Person / Time
Site:	Saint Lucie
Issue date:	06/30/2014
From:	Katzman E Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2014-208
Download: ML14203A047 (21)

Text

June 30, 2014 0

FPL.

L-2014-208 10 CFR 50.4 10 CFR 50.55a U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Re: St. Lucie Unit 2 Docket No. 50-389 Inservice Inspection Plan Third 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,Section XI, 1998 Edition with Addenda through 2000, as clarified by Code Case N-460, for the subject ASME Code Category B-A welds. The basis for the relief request is provided in the Attachment.

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

Sincerely, Eric S. Katzman Licensing Manager St. Lucie Plant Attachment ESK/KWF C4 -7 Florida Power & Light Company (U(44L 6501 S. Ocean Drive, Jensen Beach, FL 34957

L-2014-208 Attachment 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 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 Addenda through 2000 of the ASME Boiler and Pressure Vessel Code, Section Xl, "Rules for Inservice 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 Requirements Cat.

B1.10 Essentially 100% volumetric examination of all B-A B1.11 longitudinal and circumferential shell welds (does not B1.12 include shell to flange weld).

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

As defined by 10CFR50.55a(g)(6)(ii)(A)(2) and 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 of the Reactor Vessel, it is impractical to meet the examination coverage requirements of the ASME Code,Section XI, 1998 Edition with Addenda through 2000, as clarified by Code Case N-460. Relief is requested in accordance with 10 CFR 50.55a(g)(5)(iii). These areas were found during the 3rd 10-year inservice inspection interval.

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.

L-2014-208 Attachment 2 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 Described below, coupled with figures, are details of the examination limitations by weld description. Figure 1 provides an illustration of the contact UT head used for scanning from the vessel shell. Figures 2 through 15 provide the dimensions and locations of obstructions and views of each of the affected welds showing the interference caused by the permanent attachments on the Trans World System (TWS) robot and the affect of the 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 the six surveillance capsule holders. Access to approximately 17% of the examination volume is restricted. The remaining examination volume was examined with techniques which have been qualified by demonstration in accordance with Supplements 4 & 6 of the 1998 Edition with Addenda through 2000 of the ASME Code Section Xl, Appendix VIII, using the Performance Demonstration Initiative Protocol. This weld was examined from both sides of the weld, scanning both parallel and perpendicular. These ultrasonic examinations did not reveal any recordable or reportable flaws in accordance with 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 scan limitations caused by the six surveillance capsule holders. The weld is covered by the six surveillance capsule holders. Figure 3 provides dimensional information 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 six surveillance capsule holders.

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

Examination Category B-A, Item B1.21 The examination of the Figure IWB-2500-3 A-B-C-D volume is limited due to the proximity of the Core Barrel Stabilizers and Core Lugs. Access to approximately 29% of the examination volume is restricted. The remaining examination volume was examined with techniques which have been qualified by demonstration in accordance with Supplements 4 & 6 of the 1998 Edition with Addenda through 2000 of the ASME Code Section Xl, Appendix VIII, using the Performance Demonstration Initiative Protocol. This weld was examined from both sides of the weld, scanning both parallel and perpendicular to the weld. These ultrasonic examinations did not reveal any recordable or reportable flaws in accordance with 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 scan limitations caused by the Core Barrel Stabilizers and Core Lugs. Figure 6

L-2014-208 Attachment 3 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 provides dimensional information for the core barrel stabilizers and core lugs and their locations in the reactor vessel. Figure 7 is a roll out view showing the reactor 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 the core barrel stabilizers and core lugs.

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

Examination Category B-A, Item B1.12 The examination of the Figure IWB-2500-2 A-B-C-D volume is limited due to the outlet nozzle at zero degrees integral extension. Access to approximately 37%

of the examination volume is restricted. The remaining examination volume was examined with techniques which have been qualified by demonstration in accordance with Supplements 4 & 6 of the 1998 Edition with Addenda through 2000 of the ASME Code Section XI, Appendix VIII, using the Performance Demonstration Initiative Protocol. This weld was examined from both sides of the weld, scanning both parallel and perpendicular to the weld. These ultrasonic examinations did not reveal any recordable or reportable flaws in accordance with 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 showing the scan limitation caused by the outlet nozzle at zero degrees integral extension. Figure 10 provides dimensional information and the affect the outlet nozzle at zero integral extension had on scanning. Figure 11 is a roll out view showing the reactor vessel inside surface scan areas (cross hatched) for the upper shell longitudinal seam weld at 15 degrees.

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

Examination Category B-A, Item B13.22 The examination of the Figure IWB-2500-3 E-F-G-H volume is limited due to the proximity 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-F examination volume is restricted due to limited access behind the flow baffle.

The remaining examination volume was examined with techniques which have been qualified by demonstration in accordance with Supplements 4 & 6 of the 1998 Edition with Addenda through 2000 of the ASME Code Section XI, Appendix VIII, using the Performance Demonstration Initiative Protocol. This weld was examined from both sides of the weld, scanning both parallel and perpendicular to the weld. These ultrasonic examinations did not reveal any recordable 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 showing scan 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

L-2014-208 Attachment 4 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 their affect on scanning. Figure 15 is a roll out view showing the reactor vessel inside surface scan areas (cross hatched) for the peel segment welds and the locations of the core lugs.

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 were performed to the maximum extent possible. For the welds listed in this relief request, it is not possible to remove the permanently attached obstructions to increase ASME Code coverage without significant work, increased radiation 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 the requirements of 10CFR50.55a, plant technical specifications, and the 1998 Edition with Addenda through 2000, of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Xl. When a component has conditions which limit the examination volume, Florida Power and Light 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.

FPL performed mechanized ultrasonic examinations of the reactor vessel during the 2012 (SL2-20) refueling outage.

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.

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

L-2014-208 Attachment 5 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 permanently installed attachments inside the reactor vessel limit additional scanning of the 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 Table IWB-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 in accordance with ASME Code Case N-648-1, as amended by 10CFR50.55a. With the exception of acceptable visual indications identified at the top of the material surveillance capsule holders at the 83 and 97 degree azimuths, the visual examinations revealed no indications.

The subject welds were also examined in the second interval during the 10-year reactor vessel examination. The second interval examinations did not reveal any reportable flaws.

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

7. Duration of Proposed Alternative This relief request is applicable to the St. Lucie unit 2 Third Inservice Inspection Interval which 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 for Class 1 and Class 2 Welds,Section XI, Division 1"

L-2014-208 Attachment 6 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 CONTACT 51OCK END CONTACT HEAD D RECTIONAL ARROW V

2x3 L,7 HEAD CO\FIGUFRATION FOR SHELL SCANNING (AS VyEWED FROM BACK OF ROBOHAND COUPLING)

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

Figure 1

L-2014-208 Attachment 7 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 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 capsule holders. The weld is covered by the surveillance capsule holders. These limitations occur at two circumferential locations on this weld at 1800 apart. Single sided scan parameters are used near obstructions to improve examination coverage. Coverage obtained on this weld is 83%.

Figure 2

L-2014-208 Attachment 8 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 270Y AND 90"

-263, 27'T AND AND IDELTA-40 izsTP(STP w sr)

UIMENS*UNS* SHOUWNIN DLEGIREES TOTAL SCAN AREA OF YELD101-171 IS LIMITED DUE TO 6 SURVEILLANCE HOLDERS TOTAL WELD LENGTH= 546.01 INCHES SHO- SURVEILLANCE HOLDER OBSTRUCTED RPV Intermediate Shell-to-Lower Shell Circumferential Weld (101-171)

Figure 3

L-2014-208 Attachment 9 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 I. ZRr -~v r 1 I

T

~ I:

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

Figure 4

L-2014-208 Attachment 10 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 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 Barrel Stabilizers, 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 welds A, C, and E and 43% for welds B, D, and F.

Figure 5

L-2014-208 Attachment 11 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 0.

CORE BARREL STABIUZER TYP 6X-CORE WELD 201-141 BAFFLE

'CORE LUG TYp 9x RPV Circumferential Bottom Head-to-Lower Shell Weld (201-141)

Figure 6

L-2014-208 Attachment 12 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0

[2.I-41]

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

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

Figure 7

L-2014-208 Attachment 13 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 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 nozzle reinforcement. The weld intersects the outlet nozzle and limits UT head movement adjacent to the outlet nozzle on both the upper and lower portions of the weld. Single side scan parameters are used on this weld in the axial beam directions to improve coverage. Coverage obtained on this weld is 63%.

Figure 8

L-2014-208 Attachment 14 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 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 nozzle reinforcement on the upper portion of the weld. The weld intersects the outlet nozzle and limits UT head movement adjacent to the outlet nozzle. Single side scan parameters are used on this weld in the axial beam directions to improve coverage. Coverage obtained on this weld is 63%.

Figure 9

L-2014-208 Attachment 15 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 F--- -- __--_--__

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

Figure 10

L-2014-208 Attachment 16 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 I .c.

101-121 1 - i-- i I-- rAp I,I, ,I, rAý II, I, , rrAtýý Ii U 101-122" VBFW v-i tl

-4 RPV Upper Shell Longitudinal Seam Weld at 15 Degrees (101-122-A)

Figure 11

L-2014-208 Attachment 17 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 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 peel segment welds are covered by the baffle. Single side scan parameters are used on these welds below the baffle for the axial beam directions. Coverage on the peel segment welds is 53% for welds A, C, and E and 43% for welds B, D, and F.

Figure 12

L-2014-208 Attachment 18 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 RPV Lower Head Peel Segment Welds (101-154-A through F)

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

Figure 13

L-2014-208 Attachment 19 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 FLOW RPV Lower Head Peel Segment Welds (101-154-A through F)

Figure 14

L-2014-208 Attachment 20 of 20 St. Lucie Unit 2 THIRD INSPECTION INTERVAL RELIEF REQUEST NUMBER 17, REVISION 0 1W 27 1

° U ' U U ..... .. - U "

777777:'* ' ;777Y 201-141 ,

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

Figure 15