LR-N970762, Provides Notification Re Change to Util Plan for Repairing Core Spray Nozzle Weld N5B.Commitment Change in Addition to Previously Submitted Change,Encl

Provides Notification Re Change to Util Plan for Repairing Core Spray Nozzle Weld N5B.Commitment Change in Addition to Previously Submitted Change,Encl

ML20199J625
Person / Time
Site:	Hope Creek
Issue date:	11/21/1997
From:	Eric Simpson Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LR-N970762, NUDOCS 9711280179
Download: ML20199J625 (4)

Text

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ec$c $$es company E. C. Simpson Put>he Service Doctnc and Gas Company P.O. Box 236. Haricocks Badge, f U 00038 0 & 339-1700 ,

5-- v . mo.. . .u.. mr .. NOV 211997 LR N970762 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 CHANGE TO REPAIR PLAN CORE SPRAY NOZZLE WELD THROUGH WALL LEAKAGE HOPE CREEK GENERATING STATION

• FACILITY OPERATING LICENSE NPF 57 DOCKET NO. 50 354 Gentlemen:

This letter provides notification regarding a change to the PSE&G plan for repairing Cors Spray Nozzle Weld N58. In Letter LR N970667, dated October 9,1997, and Letter LR N970696, dated October 15,1997, PSE&G submitted plans and procedures related to the repair of the subject weld. The PSE&G repair plan was subsequently approved by the NRC in a letter dated October 17,1997 (TAC Number M99755). A previous commitment change associated with the repair plan was submitted to the NRC on November 12,1997. The attached commitment change is in addition to the previously submitted change. The commitment change has been made in accordance with the Nuclear Energy Institute (NEI)" Guidelines for Managing NRC Commitments" and PSE&G Procedure NC.NA-AP.ZZ-0030(O), " Commitment Management."

Should you have any questions regarding this information, we will be pleased to discuss them with you.

Sincerely,l,

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Attachment '/

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NOV 211997 Document Control Desk 2-LR N970762 C Mr. H. Miller, Administrator - Region l U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. D. Jaffe, Licensing Project Manager HC U. S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mall Stop 14E21 Rockville, MD 20852 Mr. S. Morris (X24)

USNRC Resident inspector - HC P*r. K. Tosch, Manager IV Bureau of Nuclear Engineering P. O. Box 415 Trenton, NJ 08625

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ATTACHMENT HOPE CREEK GENERATING STATION FACILITY OPERATING LICENSE NPF 57 DOCKET NO. 50 354 COMMITMENT CHANGE RELATED TO REPAIR PLAN The following describes a commitment change made in accordance with the NEl guidelines related to the repair plan fo/ Core Spray Nozzle Wald N58. The commitment change involves eliminating the need for the repair to meet the acceptance criteria of ASME Section Ill.

DESCRIPTION / JUSTIFICATION FOR COMMITMENT CHA@%

The Hope Creek NSB Core Spray Nozzle Repair Plar 'ta w ,.. wbmitted as Attachment 2 to Letter LR-N970667 specified that the weki av : ?.y would be ultrasonically examined in accordance with Code Case N r.04 ', ' Alternative Rules for Repair of Class 1,2, and 3 Austenitic Stainless StLel Piping Section XI, Divislun 1." Paragraph (1) of this Code Case specifies that preservice examination of the overlay shall be performed in accordance with IWB 2200 and employ the acceptance standards of Table IWB-3415-2. Paragreph (h) of the Code Case further specifies that a post repair system hydrostatic test is to be performed, if the original flaws are through wall. The Hope Creek NSB Core Spray flaw was a through wall condition at the time of discovery.

The Repair Plan also specified that Code Case N-416-1, ' Alternative Pressure Test Requirement for Welded Repairs or Installation of Replacement items by Welding, Class 1,2 and 3 Section XI, Division 1', would be employed during the repair. This Code Case was chosen to provide an alternative to the hydrostatic test. Code Case N-416-1 provides for a post weld repair system leakage test at nominal operating pressure and temperature in lieu of the hydrostatic test, f at is supplemented by required volumetric and surface examinations in accordance with ASME Ill,1992 Edition, no Addenda.

As a further clarification, the Repair Plan specified that the volumetric examination that would be performed would be ultrasonic (UT), in lieu of l radiography. UT was selected because radiography would have been impractical and meaningful results would have been difficult to achieve due to ,

the geometry of the repair area. The acceptance criteria for UT acceptance was '

I ASME lil, NB-5330.

During the performance of the ultrasonic examination, a circumferentially oriented laminar type flaw was detected in the weld overlay, using O' straight beam ultrasonic examination. This condition was documented in a non-conformance report (NCR). This reported laminar flaw was identified by GE using the automated (Smart 2000 UT system), but could not be confirmed as Page 1 of 2 i j

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t Attachment LR N970762 Commitment Change Related to Repair Plan being present, when using 0 degree manual scanning equipment. In addition, there is rio discernible loss of UT back reflection signal in the location of the laminar indication, and the indication is not located where masking of the original flaws, prior to repair, would occur. Nevertheless, PSE&G conservatively assumed that the indication did indeed exist. ,

Since the overlay repair was made using a machine gas tungsten are weld (GTAW) welding process, a worst case flaw assessment wcs postulated for conservatisin, in developing the disposition to the NCR. PSE&G assumed that the indication was due to a lack of fusion. The existence of an area of lack of fusion would not be in conformance with ASME lll acceptance criteria.

Alternatively, the NCR demonstrated the acceptability of the flaw using the acceptance criteria of ASME XI,1989 Edition, no Addenda, IWB-3500, as originally specified in Code Case N 504-1. The NCR documents that a circumferentially oriented laminar flaw with maximum dimensions of 8.75 inches long by 0.32 inches wide is present. This results in a maximum flaw area of 2.8 in', which is less than the allowable value of 7.5 in'as defined in ASME Section XI Table IWB 3514-3. Therefore the flaw was considered acceptable as is.

The hydrostatic test as specified in Code Case N 504-1 was still deemed as unnecessary, based on the following:

• The weld overlay was examined in accordance with ASME lil,1992 Edition, no Addenda. The UT examination showed that there were no additional indications in the immediate vicinity. The existence of a laminar flaw, if actually present in the overlay repair, will not interact in any detrimental manner with the original flaws. Therefore, the repair of the original flaws met the intent of the original submitted Repair Den.

. The reported laminar type flaw in the overlay (i.e., mid plane) is oriented such that there would be no verification of its structural integrity by the performance of a Class 1 hydrostatic test. Note: The hydrostatic test condition for this nozzle repair would only be requircd to have been in a rarge of between 1.02 Po and a maximum of 1.10 Po, depending on tesi temperature, where Po = the nominal operating pressure corresponding with 100% rated reactor power.

Based on the above, the non-conformance was considered as acceptable with its 'use as is" disposition. Further, this change in the use of ASME Section XI UT acceptance criteria was deemed as being consistent with the intent of the original Repair Plan.

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