ML20236E242
| ML20236E242 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 03/16/1989 |
| From: | Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 89-160, NUDOCS 8903240031 | |
| Download: ML20236E242 (3) | |
Text
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VIRGINIA ELECTRIC AND Powen COMPANY j
RICIIMONU,VIROINIA 202 61
)
l W, R. C A RTWMIGHT
""Jlll"'"'
March 16, 1989 l
United States Nuclear Regulatory Commission Serial No.89-160 Attention: Document Control Desk PES /ISI/FP8:jmj j
Washington, D.C.
20555 Docket No.
50-338 License No. NPF-4 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNIT 1 i
ASME SECTION XI RELIEF RE0 VEST l
In accordance with 10 CFR 50.55a(g)(5), we are requesting relief from the ASME Section XI requirement to volumetrically examine the pressurizer and steam generator nozzle inside radiused sections on North Anna Unit 1 during the first inspection interval.
The specific ASME Section XI requirement and the basis for our request are provided in the attachment.
The last of the component examinations for the first ten-year inspection l
interval are scheduled to be completed during the current refueling outage.
In preparing for this outage end reviewing our inservice inspection program, we discovered that the subject relief request had not been submitted.
Further investigation has determined that a relief request from performing these same examinations on North Anna Unit 2 was submitted by letter dated September 4, l
1987 (Serial No. 87-285A) and is currently pending NRC approval.
The North Anna Unit 1 information was inadvertently omitted from that submittal.
Review of this relief request is required prior to the end of the 1980 North Anna Unit I refueling outage.
Should you have any questions or require additional information, please contact us immediately.
Very truly yo s,
W. R. Cartw ght Attachment 8903240031 s90316 PDR ADOCK 0500 8
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cc:
U. S. Nuclear Regulatory Commission
'101 Marietta Street, N.W.
Suite 2900
~ Atlanta, GA 30323 Mr. J. L. Caldwell NRC Senior Resident Inspector North Anna Power Station I
l l
,r ASME SECTION XI RELIEF RE0 VEST FROM VOLUMETRIC EXAMINATION REQUIREMENTS FOR CLASS 1 PRESSURIZER AND STEAM GENERATOR l
N0ZZLE INSIDE RADIUSED SECTIONS NORTH ANNA POWER STATION UNIT 1 IDENTIFICATION OF COMPONENTS AND IMPRACTICAL CODE REQUIREMENTS The 1974 Edition, Summer 1975 Addenda, of ASME Section XI, Category B-D, Item Numbers 82.2 and 83.2 requires that the nozzle inside radiused section of Category B-D nozzles on the pressurizer and the steam generator primary side be examined volumetrically in accordance with subsection IWB-2500 during each inspection interval.
Category B-D includes nozzles with full penetration welds to the vessel shell (or head).
Relief is requested from the volumetric examination requirements of the nozzle inner radiused section for the pressurizer and steam generator nozzles for the first inspection interval.
BASIS FOR RELIEF REQUEST Examination Category B-D requires the nozzle inside radiused sections of the pressurizer and steam generators be examined volumetrically.
These nozzles contain inherent geometric constraints and clad inner surfaces which limit the ability to perform meaningful volumetric (UT) examinations of the inner radii areas.
The pressurizer surge line nozzle I.D.
is physically restricted by sparger, thermal sleeve, and heater bank interferences.
Presently, there is no comprehensive examination technique, or guidance for such in the ASME Code, which would provide a conclusive assessment for the Code required volumetric examination of these inner radii, particularly since no preservice results are available for review.
Radiography (RT) is not a viable examination technique due to the same inherent geometric constraints and accessibility limitations that restrict the effectiveness of the ultrasonic examination method.
In addition, high radiation levels on primary system nozzles would expose radiographic film, causing it to " fog" beyond acceptable standards.
ALTERNATE PROVISIONS Virginia Electric and Power Company proposes to visually examine the steam generator Category B-D nozzle inside radiused sections from the I.D. during l
the current refueling outage.
The pressurizer Category B-D nozzle inside radiused sections will be VT-2 examined from the 0.D.
after the unit has reached normal pressure and temperature subsequent to the current refueling outage.
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