L-08-049, Summary of Weld Overlay Ultrasonic Examinations
| ML080380331 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 02/05/2008 |
| From: | Bezilla M FirstEnergy Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-08-049, TAC MD4452 | |
| Download: ML080380331 (10) | |
Text
FENOC 00"%
5501 North State Route 2 FirstEnergy Nuclear Operating Company Oak Harbor, Ohio 43449 Mark B. Bezilla 419-321-7676 Vice President - Nuclear Fax. 419-321-7582 February 5, 2008 L-08-049 10 CFR 50.55a ATTN: Document Control Desk United States Nuclear Regulatory Commission Washington, D. C. 20555-0001
SUBJECT:
Davis-Besse Nuclear Power Station, Unit 1 Docket No. 50-346, License No. NPF-3 Summary of Weld Overlay Ultrasonic Examinations - Davis-Besse Unit 1 (TAC No.
MD4452)
By letter dated February 15, 2007, as supplemented by letters dated June 28, 2007, September 28, 2007, and November 19, 2007, the FirstEnergy Nuclear Operating Company (FENOC) requested Nuclear Regulatory Commission (NRC) approval of a proposed alternative to American Society of Mechanical Engineers Code Section XI requirements in support of weld overlay repairs for the Davis-Besse Nuclear Power Station (DBNPS). The NRC provided authorization to perform the weld overlay repairs in correspondence dated December 20, 2007.
The February 15, 2007 submittal contained a commitment to submit within 14 days of the final ultrasonic examination for the weld overlays information relevant to the indications and disposition of indications. The final ultrasonic examination was performed on January 22, 2008. The Enclosure provides the information specified in the commitment.
There are no regulatory commitments contained in this letter. If there are any questions or if additional information is required, please contact Mr. Thomas A. Lentz, Manager -
Fleet Licensing, at (330) 761-6071.
Sincerely, Mark B. Bezilla /
Ao7 ki"I
Davis-Besse Nuclear Power Station L-08-049 Page 2 of 2
Enclosure:
Summary of Weld Overlay Ultrasonic Examinations - Davis-Besse Unit 1 cc:
NRC Region III Administrator NRC Resident Inspector NRR Project Manager Utility Radiological Safety Board Executive Director, Ohio Emergency Management Agency, State of Ohio (NRC Liaison)
Enclosure L-08-049 Summary of Weld Overlay Ultrasonic Examinations - Davis-Besse Unit 1
Structural Integrity Associates, Inc.
3315 Almaden Expressway Suite 24 San Jose, CA 95118-1557 Phone:
408-978-8200 Fax: 408-978-8964 www.structnt.com bsmith@structint.com February 1, 2008 SIR-08-022-NPS, Rev. 0 Mr. Tom McCrary Davis-Besse Nuclear Power Station 5501 North State Route 2 Oak Harbor, OH 43449,
Subject:
Summary of Weld Overlay Ultrasonic Examinations - Davis-Besse Unit 1
References:
(A) FENOC letter to USNRC dated September 28, 2007;
Subject:
Response to Request for Additional Information Regarding Proposed Alternative to ASME Code Section XI Repair Requirements (TAC No. MD4452)
Dear Mr. McCrary:
The following attachment is transmitted in support of FENOC's response to commitments in the above-referenced request for alternative and response to request for additional information:
Attachment:
Summary of Weld Overlay Ultrasonic Inspections for Davis-Besse Unit 1 The Attachment addresses the commitment which stated that FENOC will submit the following information to the NRC within fourteen (14) days from completing the final ultrasonic examinations of the completed weld overlays:
" Weld overlay examination results including a listing of indications detected, and any repairs performed to the overlay material and/or base metal and reason for the repair.
- Disposition of all indications using the acceptance standards of ASME Section XI, Tables IWB-3514-1, IWB-3514-2 and/or IWB-3514-3 and, if possible, the type and nature of the weld indications.
Except for the Hot Leg Decay Heat Nozzle dissimilar metal weld, no flaws outside the IWB-3514 criteria were identified in the weld overlays, and no repairs were made to the weld overlays, the original base materials or original 82/182 weld materials. All examination results are discussed in the Attachment.
Austin, TX Centennial, CO Charlotte, NC 512-533-9191 303-792-0077 704-597-5554 Stonington, CT Silver Spring, MD Sunrise, FL Uniontown, OH 860-536-3982 301-445-8200 954-572-2902 330-899-9753 Whittier, CA Toronto, Canada 562-944-8210 905-829-9817
Mr. Tom McCrary SIR-08-022-NPS Rev. 0 February 1, 2008 Page 2 of 2 If you have any questions or comments regarding this summary, please contact one of the undersigned.
Prepared by:
Verified by:
Ned Finney Senior Consultant NDE Level III
\\2/l/08 Date Michael Lashley Associate Nuclear Plant Services 2/1/08 Date Approved by:
Barry Smith, P.E.
Senior Consultant Nuclear Plant Services 2/1/08 Date Attachment cc: M. Ruis Project File: DB-08Q-408 V
Structural Integrity Associates, Inc.
Attachment Summary of Weld Overlay Ultrasonic Examinations for Davis-Besse, Unit 1 Attachment to SIR-08-022, Rev. 0 1 of 5
Ultrasonic Examination Procedures SI-UT-126 Revision 3, Procedure for the Phased Array Ultrasonic Examination of Weld Overlaid Similar and Dissimilar Metal Welds, was used during the examinations. This procedure, and the examiners who applied the procedure, are qualified through the PDI Program at the EPRI NDE Center. No flaws outside the ASME Section XI Table IWB-3514-1, Table IWB-3514-2, or Table IWB-3514-3 acceptance standards were identified and no repairs were made to the weld overlays. Except as discussed below for the hot leg decay heat dissimilar metal weld, no other indications were detected in the base material or dissimilar metal welds examined.
SI-UT-130 Revision 0, Procedure for the Phased Array Ultrasonic Examination of Dissimilar Metal Welds, was used during the inspection of the hot leg decay heat nozzle to elbow weld following the observation of a through-wall leak detected during welding of the full structural overlay. This procedure was used for the characterization of the axial flaw which caused the leakage. No other indications were detected in the base material or dissimilar metal weld.
3" Safety Nozzle Weld Overlay Examination Component Identification:
Nozzle to Flange Weld: RC-PZR-WP-91 W/X Examination Date: January 16, 2008 Examination Time: 21:45 - 22:20 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
00 through 840 (in 1' Increments)
Circumferential Examination Angles:
00 through 620 (in 10 Increments)
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
3" Safety Nozzle Weld Overlay Examination Component Identification:
Nozzle to Flange Weld: RC-PZR-WP-91 Y/Z Examination Date: January 16, 2008 Examination Time: 21:37 - 22:14 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
00 through 840 (in 10 Increments)
Circumferential Examination Angles:
00 through 620 (in 10 Increments)
Attachment to SIR-08-022, Rev. 0 2 of 5 Structural Integrity Associates, Inc.
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
2%" Relief Nozzle Weld Overlay Examination Component Identification:
Nozzle-to-Safe-End Weld: RC-PZR-WP-91 Z/W Safe-End-to-Pipe Weld: RC-30-CCA-8-1-FW 10 Examination Date: January 18, 2008 Examination Time: 22:32 - 23:05 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material and Outer 25% Safe End-to-Pipe Weld & Adjacent Base Material Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
00 through 840 (in 10 Increments)
Circumferential Examination Angles:
00 through 600 (in 1' Increments)
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
Spray Nozzle Weld Overlay Examination Component Identification:
Nozzle to Safe End Weld: RC-PZR-WP-102 Safe End to Pipe Weld: RC-MK-A-90-FW56 Examination Date: January 20, 2008 Examination Time 13:08 - 14:08 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material and Outer 25% Safe End-to-Pipe Weld & Adjacent Base Material Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
0' through 830 (in 10 Increments)
Circumferential Examination Angles:
00 through 61 0 (in 10 Increments)
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
Pressurizer Surge Nozzle Weld Overlay Examination Component Identification:
Nozzle to Safe End Weld: RC-PZR-WP-23 Attachment to SIR-08-022, Rev. 0 3 of 5 4lA a
Examination Date: January 10, 2008 Examination Time: 16:44 - 17:24 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material.
Examination Coverage: 100% coverage of the Code-required volume was achieved, during the examinations.
Axial Examination Angles:
0' through 830 (in 1' Increments)
Circumferential Examination Angles:
00 through 68' (in 10 Increments)
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
Hot Leg Surge Nozzle Weld Overlay Examination Component Identification:
Nozzle to Pipe Weld: RC-MK-A-82-FW54 Examination Date: January 10, 2008 Examination Time: 16:44 - 17:24 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material.
Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
00 through 840 (in 1 0 Increments)
Circumferential Examination Angles:
00 through 700 (in 10 Increments)
Examination Summary: No suspected flaw indications were observed during the examinations.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during the examination.
Hot Leg Decay Heat Nozzle Dissimilar Metal Weld Examination Component Identification:Nozzle to Elbow Weld: DH-33A-CCA-4-1-FW1 Examination Date:
January 10 and 11, 2008 Examination Times: 22:00 - 01:15 and January 11, 2008 Examination Times: 09:45 - 10:15 Examination Regions: Dissimilar Metal Weld & Adjacent Base Material Axial Examination Angles:
Longitudinal 00 through 840 (in 10 Increments)
Shear 250 through 850 (in 10 Increments)
Circumferential Examination Angles:
00 through 690 (in 10 Increments)
(For the Circumferential Examination only a longitudinal wave mode is required.)
Attachment to SIR-08-022, Rev. 0 4 of 5 Structural Integrity Associates, Inc.
Examination Summary: One axial flaw indication was detected following the observation of a through-wall leak which occurred during welding of the full structural overlay. No other recordable indications were noted in area of interest 3600. The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The examination gain was again adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height.
Hot Leg Decay Heat Nozzle Weld Overlay Examination Component Identification:
Nozzle to Elbow Weld: DH-33A-CCA-4-1-FW1 Examination Date: January 22, 2008 Examination Time: 14:09 - 16:21 Examination Regions: Weld Overlay Material, Outer 25% Dissimilar Metal Weld & Adjacent Base Material Examination Coverage: 100% coverage of the Code-required volume was achieved during the examinations.
Axial Examination Angles:
0' through 840 (in 10 Increments)
Circumferential Examination Angles:
00 through 700 (in 10 Increments)
Examination Summary: One indication was recorded in the WOL material, which was characterized as a circumferential planer sub-surface indication in the WOL material. This indication is outside the ISI examination volume between the 1800 and 2700 azimuth as stamped by WSI. No other suspected planer or laminar flaw indications were observed within the weld overlay material. This indication is acceptable in accordance with ASME Sec XI, Table IWB-3514-2 as characterized in accordance with IWA-3300.
The previously identified axial base material flaw was observed and recorded during the ISI examination. No additional suspected flaw indications were observed within the ISI examination volume. The axial indication is between the 90' and 1800 azimuth at 14.5" as stamped by WSI.
The examination gain was adjusted to maintain the procedure-specified baseline noise level from 5% to 20% of full screen height. The lower range of examination angles detected responses from the inside surface of the component which were useful for monitoring search unit contact /
coupling effectiveness during these examinations.
Attachment to SIR-08-022, Rev. 0 5 of 5 Structural Integrity Associates, Inc.