ML13079A141

CFR 50.55a Request, Relief Request RR-4L3 Inservice Inspection Impracticality Examination Limitations Due to Configuration Fourth Ten-Year Inservice Inspection Program Interval

ML13079A141
Person / Time
Site:	Point Beach
Issue date:	03/19/2013
From:	Meyer L Point Beach
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NRC 2013-0020
Download: ML13079A141 (6)

Text

NEXT March 19,2013 POINT BEACl NRC 2013-0019 10 CFR 50.55a U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Point Beach Nuclear Plant Unit 2 Docket 50-301 Renewed License No. DPR-27 1 0 CFR 50.55a Request, Relief Request RR-4L2 lnservice lns~ection lm~racticalitv Examination Limitations Due to Configuration Fourth Ten-Year lnservice lns~ection Program Interval In accordance with 10 CFR 50.55aI "Codes and Standards," Paragraph (a)(3)(i), NextEra Energy Point Beach, LLC (NextEra) requests that the Nuclear Regulatory Commission (NRC) grant relief from the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code),Section XI, 1998 Edition through 2000 Addenda requirement that the inner radius sections of all nozzles at terminal ends of piping runs be volumetrically examined.

Relief is requested on the basis that alternative methods will provide an acceptable level of quality and safety. Specifically, relief is requested because the geometry of the Unit 2 steam generator main steam outlet nozzles nozzle design does not result in a true inner radius with the bored flow restrictor holes. Therefore, no meaningful examination can be performed. This design does not entail a typical nozzle with a radius as described in Figure IWC-2500-4, but instead has several "corner regions" which correspond to each bored hole. As a result, the design of the nozzle is considered to be not applicable to the Code requirement and compliance with the Code should not be required. Therefore, no alternate examinations of the Main Steam nozzle inner radius section are proposed.

NextEra requests approval of this request as described in the enclosure prior to December 31,2013. NextEra Energy Point Beach, LLC, 6610 Nuclear Road, Two Rivers, WI 54241 Document Control Desk Page 2 Summarv of Commitments This submittal contains no new commitments or revisions to existing commitments.

Very truly yours, NextEra Energy Point Beach, LLC Enclosure Regional Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC PSCW Mr. Mike Verhagan, Department of Commerce, State of Wisconsin ENCLOSURE RELIEF REQUEST RR-4L2 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT UNIT 2 10 CFR 50.55a REQUEST, RELIEF REQUEST RR-4L2 INSERVICE INSPECTION IMPRACTICALITY EXAMINATION LIMITATIONS DUE TO CONFIGURATION FOURTH TEN-YEAR INSERVICE INSPECTION PROGRAM INTERVAL ASME Code Component(s)

Affected Code Class: Examination Category:

ltem Number(s):

==

Description:==

C-B Unit 2 Steam Generator Main Steam Outlet Nozzle Applicable ASME Code Edition and Addenda ASME Section XI, 1998 Edition through 2000 Addenda. Applicable Code Requirement ASME Section XI Table IWC-2500-1 Category C-B, ltem Number C2.22 - Nozzle Inside Radius Section requires that the inner radius sections of all nozzles at terminal ends of piping runs be volumetrically examined.

Note 4 of Table IWC-2500-1, Category C-B states, "in the case of multiple vessels of similar design, size, and service (such as steam generators, heat exchangers), the required examinations may be limited to one vessel or distributed among the vessels. Reason for Request Pursuant to 10 CFR 50.55a(g)(5)(iii), NextEra Energy Point Beach, LLC has determined that due to design and geometry of the Unit 2 Steam Generators, the volumetric examination requirement of nozzle inside radius sections of the Main Steam Outlet Nozzle Inner Radius Sections, as specified in Table IWC-2500-1, Examination Category C-B, ltem number C2.22 is impractical to meet. The Point Beach Nuclear Plant Unit 2 steam generator main steam outlet nozzles are one piece that contain a set of seven holes bored parallel to the nozzle centerline. These seven flow limiting holes create an essentially square transition (i.e., no inner Page 1 of 3 radius) to the nozzle, making it ultrasonically impractical to examine. In addition, this design of nozzle does not match the typical figures found in Figure IWC-2500-4.

See Figure 4L2-I for configuration drawing. Proposed Alternative and Basis for Use The geometry of this nozzle design, with the bored flow restrictor holes, does not have a true inner radius; therefore, no meaningful examination can be performed. This design is not the same as a typical nozzle with a radius as described in Figure IWC-2500-4, but instead has several "corner regionsJ' which correspond to each bored hole. As a result, the Code requirement is not considered to be applicable to the design of the nozzle and compliance with the Code should not be required.

Therefore, no alternate examinations of the Main Steam nozzle inner radius section are proposed. The subject nozzles receive a visual (VT-2) examination each inspection period during the system leakage test as required by Section XI, Table IWC-2500-1, Examination Category C-H. The required VT-2 examination performed each inspection period provides an acceptable level of quality and safety for the subject sections of the steam generators.

Duration of Proposed Alternative Relief is requested for the fourth 10-year inservice inspection interval for Point Beach Nuclear Plant, Unit 2, which began on July 1,2002 and ended on July 31,2012. Precedents Similar relief requests documenting limited examinations have been granted to the following plants: a NRC Letter to Seabrook Station, Dated June 27,2012, Seabrook Station, Unit No. 1 - Request for Relief 31 R-1, Examination Category C-B Pressure Retaining Nozzle Welds in Vessels (TAC No. ME7257) (ML120880245) Page 2 of 3 Figure 4L2-1 PBNP Unit 2 Steam Generator Main Steam Outlet Nozzle Configuration STEAM IYMZ- Page 3 of 3