ML032591158
| ML032591158 | |
| Person / Time | |
|---|---|
| Site: | Oconee, Mcguire, Catawba  (DPR-038, DPR-047, DPR-055, NPF-035, NPF-052) |
| Issue date: | 09/08/2003 |
| From: | Mccollum W Duke Energy Corp |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 03-GO-006 | |
| Download: ML032591158 (11) | |
Text
k Duke c W Energy.
Duke Energy Corporation 526 South Church Street P.O. Box 1006 Charlotte, NC 28201-1006 September 8, 2003 U. S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 ATTENTION: Document Control Desk
SUBJECT:
Duke Energy Corporation Oconee Units 1, 2, & 3 Docket Nos. 50-269, 50-270, 50-287 McGuire Nuclear Station, Unit 2 Docket No. 50-370 Catawba Nuclear Station, Units 1 & 2 Docket Nos. 50-413, 50-414 Relief Request for Alternative to ASME Section XI Relief Request 03-GO-006 Pursuant to 10 CFR 50.55a (a) (3) (i), Duke Energy Corporation (Duke) requests the use of an alternative to the ASME Boiler and Pressure Vessel Code,Section XI, Appendix I, 1-2100, 1989 Edition with no addenda for the remainder of the third inspection interval of Oconee Units 1, 2, and 3, and the second inspection interval of McGuire Unit 2 and Catawba Units 1 and 2.
Specifically, Duke requests relief from specific requirements when ultrasonic examination is performed on circumferential and longitudinal welds in steam generators and pressurizers. As an alternate, Duke requests approval to use the ultrasonic techniques, equipment, procedures, and personnel qualifications in accordance with ASME Section XI, Appendix VIII, Supplements 4 and 6, 1995 Edition through 1996 Addenda when examining circumferential and longitudinal welds greater than 2 inches in thickness in steam generators and pressurizers.
A detailed description of the proposed alternative and justification is included as an attachment to this letter. Duke is requesting approval of this request by September 8, 2004, to support the Catawba Unit 2 and Oconee Unit 3 outages in the fall of 2004. Questions regarding this request may be directed to R. K. Nader at 704-382-0979.
Very truly yours, W. R. McCollum, Jr.
Senior Vice President, uclear Support ADY-7
U. S. Nuclear Regulatory Commission September 8, 2003 Page 2 Attachment xc wlatt:
L. A. Reyes, Regional Administrator U. S. Nuclear Regulatory Commission, Region II Sam Nunn Atlanta Federal Center 23T85 61 Forsyth St., SW Atlanta, GA 30303 L. N. 01shan (Addressee only)
NRC Senior Project Manager (ONS)
U. S. Nuclear Regulatory Commission Mail Stop 0-8 H12 Washington, DC 20555-0001 R. E. Martin (Addressee only)
NRC Senior Project Manager (MNS and CNS)
U. S. Nuclear Regulatory Commission Mail Stop 0-8 H12 Washington, DC 20555-0001 M. E. Shannon, NRC Senior Resident Inspector (ONS)
E. F. Guthrie, NRC Senior Resident Inspector (CNS)
J. B. Brady, NRC Senior Resident Inspector (MNS)
U. S. Nuclear Regulatory Commission September 8, 2003 Page 3 bxc wI att:
M. T. Cash (ECO50)
C. J. Thomas (MGOIRC)
K. L Crane (MGO1RC)
N. T. Simms (MGOIRC)
G. D. Gilbert (CNO1RC)
K. E. Nicholson (CNO1RC)
L. J. Rudy (CNORC)X L. E. Nicholson (ON03RC)
J. E. Smith (ON03RC)
R. P. Todd (MD02FE)
J. M. Ferguson - Date File (CNO1SA)
R. K. Rhyne (ECO7J)
J. J. McArdle (EC07J)
T. Wills (WC28H)
R. 0. Sharpe (WC28H)
J. 0. Barbour (ECO7J)
MNS MasterFile MC-801.01 (MG01DM)
CNS MasterFile CN-801.01 (CN04DM)
ONS MasterFile ON-801.01 (ON03DM)
ELL
U. S. Nuclear Regulatory Commission September 8, 2003 Page 4 bxc w/ attach: North Carolina Municipal Power Agency Number 1 1427 Meadowwood Boulevard P. O. Box 29513 Raleigh, NC 27626 Saluda River Electric Cooperative, Inc.
P.O. Box 929 Laurens, SC 29360 Piedmont Municipal Power Agency 121 Village Drive Greer, SC 29651 T. Richard Puryear North Carolina Electric Membership Corporation P.O. Box 27306 Raleigh, NC 27611
03-GO-006 Page of 7 DUKE ENERGY CORPORATION McGuire Unit 2 Catawba Units 1 and 2 Oconee Units 1, 2 and 3 10-YEAR INTERVAL REQUEST FOR RELIEF NO. 03-GO-006 Pursuant to 10CFR50.55a (a) (3) (i), Duke Energy Corporation pro-poses an alternative to the requirements of ASME Section XI, 1989 Edition with no addenda.
The following information is submitted in support of our proposed alternative.
I.
System/Components for Which the Alternative Appliese Category B-B Pressure Retaining Welds in Vessels Other than Reactor Vessels Item Number:
B2.11 Pressurizer Circumferential and Shell-to-Head Welds B2.12 Pressurizer Longitudinal and Shell-to-Head Welds B2.31 Steam Generator (Primary Side) Circumferential Head Welds B2.40 Tubesheet-to-Head Welds Category C-A Pressure Retaining Welds in Pressure Vessels Item Number:
Cl 10 Shell Circumferential Welds C1.20 Head Circumferential Welds C1.30 Tubesheet-to-Shell Welds II.
Code Requirements ASME Section XI, Appendix I, 1-2100, 1989 Edition with no addenda requires that ultrasonic examination of pressure vessel welds greater than 2 inches in thickness be examined in accordance with ASME Section V, Article 4, 1989 Edition with no addenda as supplemented by the addi-tional requirements of Appendix I.
03-GO-006 Page 2 of 7 III. Code Requirement for Which the Alternative is Requesteds ASME Section RI-, Appendix I, I-2100 references ASME Section V, Article 4 for the ultrasonic examination of welds in fer-ritic pressure vessels greater than 2 inches in thickness.
Duke Energy Corporation proposes alternatives to the re-quirements of ASME Section V, Article 4 as shown below when manual ultrasonic examination is performed on circumferen-tial and longitudinal welds in steam generators and pressurizers.
T-424.3 Scanning Sensitivity Level.
"Scanning shall be performed at a gain setting at least two times the reference level, except that the reference level shall be used when electronic distance-amplitude correction is used with automated recording.
For -both manual -and mechanized examinations, recording of indications shall be made with respect to the reference level. -During scanning only the gain or attenuator controls may be adjusted.
Any adjustments to the-other controls shall require recalibra-tion.f f
N~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Duke Energy Corporation Alternative Duke Energy Corporation proposes to record indications at the scanning sensitivity levels that have been demonstrated during procedure qualification.
T-432.1.1 Calibration Check Upon Change in the Complete Ul-
- trasonic Examination System.
"Alternate cables and search units singly and in combina-tions that have been included-in a prior system calibration may be later substituted in the system; such substitution shall not necessitate a calibration check.
When any other part of the examination system is changed, a calibration check shall be made on-the basic calibration block to verify the A,, and T points on the sweep and distance amplitude correction values recorded satisfy the requirements of T-433.1 and T-433.2."
Duke Energy Corporation Alternative Duke Energy Corporation proposes to verify sweep using an International Institute of Welding (IIW) block, and to ver-ify amplitude using a single reflector in the basic calibration block.
03-GO-006 Page 3 of 7 T-432.1.2 Calibration Check on Basic Calibration Block or Simulator Check.
"A calibration 'check on at least two'of the basic reflectors in the basic calibration block T-441.1.1) shall be made at the finish of each examination, every 12 hr during the ex-amination, and when examination personnel (except for mechanized equipment) are changed.
The sweep and distance amplitude correction values recorded shall satisfy the re-quirements of T-433.l and. T-433.2.a Duke Energy Corporation Alternative Duke Energy Corporation proposes to perform calibration checks using an International:Institute of Welding (IIW) block to verify sweep and a-using single reflector in the basic calibration block to verify amplitude.
T-432.3.1 Angle Beam Calibration "The calibration shall provide.the following measurements (Appendix B contains a general technique):
():
(b) Distance-amplitude correction;"
Duke Energy Corporation Alternative Duke Energy Corporation proposes to use a performance based calibration technique in lieu of distance-amplitude correc-tion.
T-432.3.2 Straight Beam Calibration
'The method of calibration shall provide the following meas-urements (Appendix C gives a general technique):
(a) sweep range calibration; (b) distance-amplitude correction; Duke Energy Corporation Alternative Duke Energy Corporation proposes toexclude straight beam examination.
T-433.1 Sweep Range Calibration "If any pointon the DAC curve has moved on-the sweep line more than 10% of the sweep division reading, correct the sweep range calibration and note the correction in the ex-amination record.,
0
,tf-i,,
o 03-GO-006 Page 4 of 7 Duke Energy Corporation Alternative Duke Energy Corporation proposes using a single reflector in the basic calibration block as an alternative to a DAC, and will apply the same acceptance criteria stated in the Code.
T-433.2 DAC Correction-
"If any point on the distance-amplitude correction (DAC) curve has decreased 20% or 2 dB of its amplitude, all data sheets since the last-calibration or-calibration-check shall be marked void.
A new calibration shall be made and re-corded and the voided-examination areas shall be reexamined.
If any point on the distance-amplitude correction (DAC) curve has increased more-than 20% or 2 dB of its amplitude, all recorded indications since the last valid calibration or calibration check shall -be evaluated with the corrected calibration and their values shall be changed on the data sheets.ff Duke Energy Corporation Alternative Duke Energy Corporation proposes using a single reflector in the basic-calibration block as an alternative to a DAC, and apply the same acceptance criteria -stated
-in the Code.
T-441.3.2.1 General Scanning Requirements "These volumes shall be scanned by straight and angle beam techniques as described in detail in T-441.3.2.3 (a) and (b), and T-441.3.2.5.
Three angle beams, having nominal an-gles of 45 deg., 60 deg., and 70 deg. with respect to a perpendicular to the examination surface, shall generally be used.
Beam angles other than 45 deg. and 60 deg. are per-mitted provided the measured difference between angles is at least 10 deg.fX Duke Energy Corporation Alternative Duke Energy Corporation proposes to examine the required volume with 60 deg. and 70 deg. beam angles qualified by performance-demonstration
-,Straight beam and the 45 deg.
beam angle will-not be used to detect-planar reflectors.
Duke -Energy Corporation will use a straight-beam to detect laminations prior to the initial angle beam examination.
T-441.3.2.5 Angle Beam Scanning "The examination using the 70 deg. beam shall cover the near surface to a depth of 1 in. or A thickness, whichever is greater.
1.
03-GO-006 Page 5 of 7 Duke Energy Corporation Alternative Duke Energy Corporation proposes to use the 70 deg. beam an-gle to cover the -near surface to a depth of 1 in. or 15% of the thickness, whichever is greater.
T-441.3.2.8 Recording Angle Beam Examination Data for Planar Reflectors
" (a) Record all reflectors that'produce a response equal to or greater than 20% of the distance-amplitude correction (DAC).
However, clad interface and backwall reflections need not be recorded.
Record surface reflectors that pro-duce a response equal to or exceeding the calibration amplitude established per T-432.3.1 (d).W Duke Energy Corporation Alternative Duke Energy -Corporation-proposes recording angle beam data as follows:
- 1.
Clad Vessels e
Surface reflectors that produce a 3:1 signal to noise ratio when compared to the clad roll at the scanning gain level.
- Non-surface connected reflectors that have ampli-tudes greater than 20% of full screen height at the scanning gain level.
- 2.
Non-Clad Vessels
,All reflectors that have amplitudes greater than 20% of full screen height at the scanning gain level.
- 3. -Additional factors used in determining'if an indication should be recorded are:
- An indication is detected and plotted in the same location from two opposite directions;
- An indication detected from a perpendicular scan plots to the same location as an indication found in a parallel scan;
- An indication "travels' or shows target motion;
- Tip diffracted signals are present with the indica-tion.
- ^-,
03-GO-006 Page 6 of 7 IV. Basis for the Relief: ASME Section V, Article 4 describes the required techniques to be used for the ultrasonic exami-nation of welds.4in! ferritic pressure-.vessels greater than 2 inches in thickness.
These techniques _were first published in ASME Section V, Article 4, 1974 Edition, Summer 1975 Ad-denda.
The calibration technique and recording criteria based on the use of a distance-amplitude-correction curve (DAC) represented "good practice at the time and have not changed materially in twenty-eight years.
In 1999 Duke Energy Corporation participated in Appendix VIII performance demonstrations using -mock-ups with proce-dures and equipment showing that use of a DAC is irrelevant in performing ultrasonic examination of.ferritic pressure vessel welds.
The demonstrations also showed that fewer beam angles than required-by-ASME Section V, Article 4 were needed to detect flaws in -ferritic pressure vessel welds.
In addition it was found-that the 20% DAC recording criteria
.was arbitrary..The performance demonstrations were conducted
-in accordance with ASME Section XI, Code Case N-622, Supple-ments 4 and:6-and monitored by-the Performance Demonstration Initiative (PDI) at the EPRI NDE Center.
V.
Alternative Method for-Ultrasonic Exanination: Duke Energy Corporation proposes using ultrasonic techniques with equip-ment, procedures and personnel qualified in accordance with ASME Section XI, Appendix VIII, Supplements 4 and 6, 1995 Edition through.the 1996 Addenda-when examining circumferen-tial and longitudinal welds greater than 2 inches in thickness in steam-generators--and pressurizers.-The ultra-sonic procedure which Duke Energy Corporation has qualified applies to Ferritic pressure vessels.greater than-2 inches to 7.5-inches in thickness inclusive.
The manual contact techniques use 600 -and-700 refracted longitudinal wave search units.
Duke Energy Corporation realizes that all -vessel weld con-figurations cannot be fully examined by the techniques qualified Through PDI and therefore will limit the applica-tion to welds where scanning. can be accomplished in four
-orthogonal directions and achieve-coverage greater than 90%
as permitted by -Section XI Code Case N-460. Configurations that will not be examined with-the PDI qualified procedure are nozzle-to-vessel welds where access is restricted to one side of the weld, and head-to-shell welds where the ratio of the inside diameter to the outside diameter of the head pre-vents the 600 beam angle from intercepting the inside surface.
03-GO-006 Page 7 of 7 VI.
Justification for the Granting of Relief: Ultrasonic exami-nations performed in accordance with ASME Section V, Article 4 require the use of 00, 450, 600 and 700 beam angles with recording criteria that are time consuming and increase per-sonnel radiation exposure without a compensating-increase in quality or safety. Ultrasonic techniques qualified in accor-dance with Appendix VIII and administered by the PDI would increase the reliability. of the-ultrasonic examination, im-prove the level of quality and lessen personnel radiation exposure by reducing examination time without a decrease in quality or safety.
VII.- Implementation:s Duke-Energy. will perform.the-ultrasonic ex-aminations-described in Section V of this relief request for the remainder -of the 2nd-nspection interval at.-McGuire Unit 2, Catawba.-
Units 1 and 2, and the 3 inspection interval at Oconee Units 1, 2 and 3 Sponsored By J6-Date______
Reviewed By M
DateSJ D3 3