NL-07-0859, Pressurizer Nozzle Full Structural Weld Overlay Nondestructive Examination Results Spring 2007 Outage (2R12) - Revision 1

Pressurizer Nozzle Full Structural Weld Overlay Nondestructive Examination Results Spring 2007 Outage (2R12) - Revision 1

ML073300533
Person / Time
Site:	Vogtle
Issue date:	04/18/2007
From:	George B Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2R12, NL-07-0859
Download: ML073300533 (4)

Text

-'*1 Southern Nuclear Operating Company, Inc.

Post Office Box 1295 Birmingham, Alabama 35201-1295 Tel 205.992.5000 SOUTHERN ZL April 18, 2007 COMPANY Energy to Serve Your WorId '

Docket No.: 50-425 NL-07-0859 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Vogtle Electric Generating Plant - Unit.2 Pressurizer Nozzle Full Structural Weld Overlay Nondestructive Examination Results Spring 2007 Outage (2R1 2) - Revision 1 Ladies and Gentlemen:

On April 13, 2007, Southern Nuclear Operating Company (SNC) submitted letter NL-07-0803 providing the NRC examination results for the Vogtle Electric Generating Plant (VEGP) Unit 2 pressurizer nozzle full structural weld overlays and a discussion of any repairs to the overlay material and/or base metal. This information was submitted as a table in enclosure I to the letter and addressed pressurizer nozzles Nl through N-6.

Subsequent to the submittal, SNC discovered that a clarification was needed to the N-5 nozzle information provided in the table on page El-2. Enclosed is a revised page El-2 to enclosure I which supersedes and replaces the same page submitted in NL-07-0803.

This letter contains no NRC commitments. If you have any questions, please advise.

Sincerely, Manager, Nuclear Licensing BJGIDRG/daj

Enclosure:

Revision to Page El -2 of the Weld Overlay Examination Results and Repairs Table in NL-07-0803 II /Vý/

eel

U. S. Nuclear Regulatory Commission NL-07-0859 Page 2 cc: Southern Nuclear Operating Company Mr. J. T. Gasser, Executive Vice President T. E. Tynan, Vice President - Vogtle Mr. D. H. Jones, Vice President - Engineering RType: CVC7000 U. S. Nuclear Regulatory Commission Dr. W. D. Travers, Regional Administrator Mr. B. K. Singal, NRR Project Manager - Vogtle Mr. G. J. McCoy, Senior Resident Inspector - Vogtle

I.

Enclosure Vogtle Electric Generating Pressurizer Nozzle Full Plant Unit 2 Revision to Page E1-2 Structural Weld Overlay of the Weld Overlay Examination Results and Repairs Table in NL-07-0803

Enclosure I Vogtle Unit No. 2 Weld Overlay Examination Results and Repairs Table PT of Overlay PDI UT Exam Post PDI UT Repairs PDI UT Nozzle Results PT of Mitigation Layer PT of Base Metal Results/Repairs Results/Repairs Results Re-exams Two indications due to probable hot cracking:

Indication I @ 900 Length = 5.6-inches N-4 Indication 2 @ 1800 NR NRI NONE NA RELIEF NRI Length = 2.8-inches The indications were repaired and a new PT was performed with acceptable results.

Grinding was performed to remove the laminar indication. A PT examination of the Numerous rejectable An intermittent 3600 laminar excavated area was indications were found in a indication was detected by UT. It performed with i-inch wide band 3600 acceptable results. In the N-5 aroundndthe fnozzle N-SNR pie at the he velay M the te oignalsufac near the original surface nar interface heintrfce welding the ground-out to fillsixin processarea, MUI pipe end of the overlay. NRI of the safe-end to stainless steel linear PT indications were SPRAY NRI

'Me indications were weld. The likely cause was lack of observed (lengths varied repaired and a new PT was fusion. See the attached figure to from 0.125-inch to 0.250-performed with acceptable show indication location. ih Teincatons results. inch). These indications were ground out and the areas were re-welded. A new PT was performed with acceptable results.

El-2