ML18036A452
| ML18036A452 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 11/15/1991 |
| From: | Zeringue O TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-80-07, IEB-80-13, NUDOCS 9111250255 | |
| Download: ML18036A452 (12) | |
Text
ACCELERATED DISTRIBUTION DEMONSTPWTION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9111250255 DOC.DATE: 91/11/15 NOTARIZED: NO DOCKET FACIL:50-296 Browns Ferry Nuclear Power Station, Unit 3, Tennessee 05000296 AUTH NAME AUTHOR AFFILIATION ZERINGUE,O.J.
Tennessee Valley Authority RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
R
SUBJECT:
,Submits results of visual insp of core spray sparger internal pipinq to reactor vessel, performed on 911007
& 12, per NRC Bulletins 80-007
& 80-013.Reinforced brackets will be installed during outage to resolve cracking problem.
DISTRIBUTION CODE:
IE11D COPIES RECEIVED:LTR ENCL SIZE:
TITLE: Bulletin Response (50 DKT)
NOTES RECIPIENT ID CODE/NAME SANDERS,M.
WILLIAMS,J.
INTERNAL: AEOD/DOA NRR/DOEA/OEABll NRR/DREP/PEPB9 D'RR/PMAS/I LRB1 2 RES/DSIR/EIB EXTERNAL: NRC PDR COPIES LTTR ENCL 1
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1 RECIPIENT ID'ODE/NAME HEBDON,F NRR/DET/EMEB 7E NRR/DOEA/OGCBll NR~RJ3Sg/8.E2~
RE E ~0.23 RGN2 FILE 01 NSIC COPIES LTTR ENCL 1
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NOTE TO ALL"RIDS" RECIPIENTS:
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PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 15 ENCL 14
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Tennessee Valley Authority, Post Office Box 2fEO. Decatur,'Atabarna 35609 O. J. 'Ike'eringue Vice President. Browns Ferry Operations U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk Washington, D.C.
20555 Gentlemen:
In the Matter of Tennessee Valley Authority Docket No. 50-296 BROWNS FERRY NUCLEAR PLANT (BFN) UNIT 3 CORE SPRAY (CS)
SPARGERS AUGMENTED INSPECTION REPORT
Reference:
TVA letter dated April 9, 1984, Inspection and Enforcement Bulletin Nos. 80-07, BWR Jet Pump Assembly Failure, and 80-13, Cracking. in Core Spray Spargers Browns Ferry Nuclear Plant On October 18,
- 1991, TVA provided 24-hour notification, in accordance with IE Bulletin 80-13, to the onsite resident inspectors and NRC Region II of cracking found in the CS spargers on Unit 3.
This letter provides the 30-day written report required by the bulletin.
The BFN Unit 3 Cycle 6 invessel inspection of the reactor vessel was completed on October 21, 1991.
The underwater camera system used for the visual inspection was qualified by underwater viewing of a one mil (0.001) wire visual standard.
This qualified the video 'camera to view one mil cracks within the reactor vessel.
Visual inspection of the CS sparger and internal piping to the reactor vessel was performed between October 7 and October 12, 1991, in accordance with IE Bulletin 80-13.
Cracking has been identified at one location on CS Loop A and at one location on CS Loop B.
No other relevant indications were found during these CS sparger inspections.
(g)l CS Loop A header piping (see Enclosure
- 1) has an arc strike with three linear indications, less than 1/4-inch length each, located at the left side of the 120 degree T-box.
An engineering evaluation is being performed on the arc strike.
Preliminary engineering review indicates that repair is not necessary and that continued operation with the arc strike is acceptable provided that the indication is inspected for degradation during subsequent outages.
Cl 1
(
U.S. Nuclear Regulatory Commission A 3-1/2 to 4-inch linear crack with well-defined gap width has been positively identified on CS Loop B pipi'ng (see Enclosure 2). It is located near a weld-joining the CS pipe to its T-box (left side of 240 degree T-box).
TVA plans to install reinforcement brackets during this outage similar to those installed to resolve similar cracking problems that occurred at Peach Bottom and Brunswick.
No abnormalities have been found in the CS Spargers during past inspections.
The last CS Spargers inspections were performed during the Unit 3, Cycle 5 invessel inspection (completed March 12, 1984, as documented in the referenced letter).
A summary of commitments is provided in Enclosure
- 3. If you have, any questions, please telephone J. E. McCarthy, Restart Licensing Manager, at (205) 729-2703.
Sincerely,
,/
(
~PjfPg/g 0.'
Zeringue Enclosures cc.(Enclosures):
NRC Resident Inspector Browns Ferry Nuclear Plant Route 12, Box 637
- Athens, Alabama 35611 Mr. Thierry M. Ross, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. B. A. Wilson, Project Chief U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
0 4l
CORE SPRAY INTERNAL PIPING - LOOP A
, ENCLOSURE l CDRE SPRAY HEADER 9Z VESSEL p
18 9
81 Ql~l.
(A JUNCTION BOX CORE SPRAY DOWCOHER 21 16 18 19 2
1 SHROUD la SHROUD l78 MOTE:
BI AHD B2 ARE THE CORE SPRAY INTERNAL PIPING lIALL.BRACKETS Q C1RCLE DIOlCATEO IIELO LOCATEONS (A) (3) linear inciications connected to arc strike
CORE SPRAY INTERNAL PIPING LOOP B
ENCLOSURE 2
CORE SPRAY HEADER 12 VESSEL 240 ie 9
el JUNCTION BOX CORE SPRAY OOMNCOMER 22 SHROUD 198 SHROUD 358 NOTE:
B1 AND B2 ARE THE CORE SPRAY INTERNAL PIPING MALL BRACKETS Q CIRCLE IOOICATES MELO LOCATIONS.
{B) f.ines indications 3-4" running along fusion la.ne of weld in base metal.
ENCLOSURE 3
SUMMARY
OF COMMITMENTS'VA will inspect the arc strike identified on the Unit 3 Core Spray Loop A header piping for signs of degradation during subsequent outages.
Install reinforcement brackets on Unit 3 CS Loop B piping prior to restart.
41 J