ML20238D629
| ML20238D629 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 09/04/1987 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| 87-285A, NUDOCS 8709110295 | |
| Download: ML20238D629 (5) | |
Text
{{#Wiki_filter:.__ VInonilA ELEcTuzc AND POWEu COMI%NY HIcuwoxn,VIHOINIA 20061 v.L.STBWANT c' VICE PRESIDENT i . wmum ornamon. September 4, 1987 U. S. Nuclear Regulatory Commission Serial No. 87-285A Attention:' Document Control Desk-NOD /ISI Rev. 1 Washington, D. C. 20555 Docket No. 50-339. License No. NPF-7' Gentlemen: VIRGIFilA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNIT 2 ASME SECTION XI RELIEF REQUESTS On June 8, 1987, Virginia Electric and Power Company submitted North Anna Unit 2 ASME Section XI relief requests (Serial No. 87-285). On July 9,
- 1987, Virginia Electric and Power representatives met with members of the Nuclear Regulatory Commission staff.- During this meeting, staff members ' requested clarification of our June 8 request.
This-clarification is provided in. j If you desire additional information, please contact me. Very truly yours, G- ,, 4\\ .k Nh W. L. Stewart Attachment cc: U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W. j Suite 2900 i Atlanta, GA 30323 Mr. J. L. Caldwell NRC Senior Resident Inspector North Anna Power Station i - ()k, N)s 8709110295 870904 PDR ADOCK 05000339 p PDR
d (- Attachment I l Page 01 of 03 Relief Request Description Page 1 Item Number B2.2 & B3.2 of Category B-D 2 Nozzle-to-Vessel Welds and Nozzle Inside Radiused Section. 2 Item Number B4.6 of Category B-J - Branch 3 Pipe Connection Welds exceeding six inches in diameter. I
to+ 4 Attachment I Page 02 of 03 ASME Section XI Relief Request From NDE Examinations on Class 1 Pressurizer and Steam Generator North Anna Power Station Unit 2 7f Examination Category B-D, Full Penetration Welds of Nozzles in Vessels lqd3y Item Number B2.2 Nozzle-to-Vessel Welds and Nozzle Inside Radiused -{[ Section and B3.2 Nozzle-to-Head Welds and Nozzle Inside Radiused Section on the Primary Side p) IDENTIFICATION OF COMPONENTS AND IMPRACTICAL CODE REQUIREMENTS N' The Code reqtires that the nozzle inside radius section of Category B-D nozzles on the pressurizer and steam generator 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 l inner radii for the pressurizer and steam generator nozzles. BASIS FOR RELIEF REQUEST Examination Category B-D requires the nozz?m inside radiused sections of the pressurizer and steam generators be exam.ned volumetrically. These nozzles contain inherent geometric constraints and clad inner surfaces which limit the ability to perfonn meaningful volumetric (UT) examinations of the inner radii areas. The pressurizer surge line nozzle I.D. is physically restricted by the sparger, the 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 .I Generator Category B-D nozzles inside radius sections from the I. D. when accessible prior to the end of the inspection interval and perform a VT-2 examination of the Pressurizer Category B-D nozzles inside radius sections from the 0.D. after the unit has reached normal pressure and temperature prior to the end of the inspection interval. I)o
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- Q ASMESectfynXI-ReAllefRequest' i
C . From NCE Examinations ou T Class 1 Piping Pressure Boundary 3 g o:.l(r S,- North Anna Power Station Unit 2 l! I ;), o it Examination Category'B-J Predsure Retaining Welds in Piping ) ' Item Number B4.6, Branch Pipe Connection Welds Exceeding Six Inches In Diameter t I s. 1 as s,9 ,1 ~ IDENTIFICATION OF COMPONENTS'AND IMPRACTIC#A CODE REQUIREMENTS g l w Section XI of. the ASME Boiler and Pressure Vessel Code, 1974 Edition thr'ough. ,the Summer 1975 Addenda,' requires a volumstric. examination of branch.. pipjp l connection welds on piping having a' nominal pipe size of six inches or greater'i in particular, Table T E-2500 requires an' ultrasonic examination of thei wel'd. .j 3 . metal and the base metalifor?one pipe wall thickness. [ s m full volumetriedramtnation doe to the piksicalL 1 Relief is requested from a configuration of the branch nozzle connection welds Tn the following 11nbs - LIljE, ISO t WELD .j A j .s o.: 14"-RH-401 VGB l-4100 18BC l g;""-RC-416-VGBM-4100-19BC q j n ct -RC-417 VGB-1-41DU 26BC i s3 ,1 12"-RC-422 VGB 4100 29BC I 1 '6"-RC-418 VGB-1-4200 ~18BC' 6"-RC-419 VGB-1-4200 24BC l 12" -RC-42 3 - . VGB--l-4200 26BC 12"-RC-424 VGB-1-4300. 28BC i 6"-RC-421 VGB 430Q 18BC
- i. 14"-RC-410 VGB-l-4300 -
19BC s 6"-RC-420 VGB 4300 25BC 3 BASIS FOR RELIEF 4. Due to the: configuration of the weld crown, Ucrann0ucer contact cannot be maintained on the weld. The slope of the. weld croyn precludes examination of 'the entire weld volume when scanning from the veld crows. f D, ' ALTERNATE PROVISIONS-w .The volumetric examinations on these welds will ' be performed to the extent practical., i A sit ilar relief request was granted for Surry by letter from Mr. Steven A. j.. Varga dated January 24, 1984. l 1 i'O. j i ....'u m _. j
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