ML19263C635
| ML19263C635 | |
| Person / Time | |
|---|---|
| Site: | Hatch, Vogtle  |
| Issue date: | 02/02/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | John Miller GEORGIA POWER CO. |
| References | |
| NUDOCS 7902280071 | |
| Download: ML19263C635 (5) | |
Text
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UNITED STATES
/ 8800g'o, NUCLEAR REGULATORY COMMISSION
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REGloN 11
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5 4'
101 M ARIETT A STRE ET. N.W.
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ATLANT A, GEoR GI A 30303 o
FEB 2 1979
+ +......
In Reply Refer To:
Rll:JPO 50-321, 50-366 50-424, 50-425 Georgia Power C apany Attn:
Mr. J.1:. Miller, Jr.
Executive Vice President 270 Peachtree Street, N. W.
Atlanta, Georgia 30303 Gentlemen:
This Information Notice is provided as an early notification of a possibly significant matter. It is expected that recipients will review the information f or possible applicability to their f acilities.
No specific action or response is requested at this time.
If further h7C evaluatiens so indicate, an IE Circular or Eulletin vill be issued to recoc: mend or request specific licensee actions.
If you have questions the Director of the appropriate regarding this matter, please contact NRC Regional Office.
Sincerely,
/
6.%sfY s
- f sees y,-
Reilly Direetct
Enclosures:
1.
IE Information Notice No. 79-01 2.
List e# IE Information Notices Ins-d in 1979 7902280071 Q
FEB 2 1979 Georgia Power Company cc w/ enc 1:
K. M. Gillespie Construction Project Manager Plant E. I. Hatch P. O. Box 439 Baxley, Georgia 31513 M. Manry, Plant Manager Plant E. I. Hatch P. O. Box 442 Baxley, Georgia 31513 E. D. Groover QA Site Supervisor Vogtle Nuclear Plant P. O. Box 282 Waynesboro, Georgia 30830 O
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.
20555 February 2, 1979 IE Information Notice No. 79-01 BERGEN-PATERSON HYDRAULIC SHOCK AND SWAY ARRESTORS (HSSA)
On December 4, 1978, Rancho Seco Nuclear Generating Station reported the failure of seven Bergen-Paterson HSSA (Snubber) units to lockup in the co=pression direction and the failure of one additional unit to 1cckup in the extension direction. These failures were identified during surveillance testing and the affected models included HSSA-3-6, HSSA-10-6 and BSSA-20-6. When the units were disassembled, the licensee observed damage to the poppet valve and seat on the compression side of the valve blocks of the seven units that failed in the compression direction.
It was also observed that five of the seven units had the poppet spring entrapped between the poppet and the seat.
The licensee attributed the seven failures in the co=pression direction to abusive handling during cocpression of the units for installation following testing at the previous refueling outage. The cause of the single failure in the extension direction has not been determined. In addition to exercising greater care in reinstallation, the licensee coc=itted to functionally test all Bergen-Paterson snubbers subjected to transient cond!! ions which ca.use either physical damage to or significant movement of piping. This testing vill include verification of piston movement, lockup and bleed. The Bergen-Paterson Technical Maintenance Manual recom= ends that additional inspections should be made on units which may have participated in an unusual shock occurrence involving known damage to piping or equipment.
On January 3,1979, the licensee reported that the decay heat removal system had been subjected to a transient condition in the form of a
" water ha=cer."
This trar.sient, caused pipe movement great enough to damage two rigid pipe support wall attachments. The subsequent functional testing of the affected Bergen-Paterson units revealed that one of seven units failed the lockup test.
This unit 0Hodel No. HSSA-3-6) was disasse= bled and damage to the poppet valve and seat was observed.
The damage to the poppet valves is presently being reviewed by both the licensee and Bergen-Paterson. At this time, the cause of damage has not been completely defined nor has appropriate corrective action been determined. Other licensees have reported instances of poppet valve damage; however, the cause and extent of damage are not known at this tint.
4
IE Information Notice No. 79-01 February 2,1979 This information is provided as an early notification of a possibly significant matter.
It is expected that recipients will review the information for possible applicability to their facilities. No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular or Bulletin vill be issued to recommend er request specific licensee actions.
If you have questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
Page 2 of 2
IE Information Notice No. 79-01 February 2, 1979 LISTIhG OF IE IhTORMATION NOTICES ISSUED IN 1979 Information Subj ect Date Issued To Notice No.
Issued An Information Notice is a new method of coczmunicating items of potential interest to licensees. This iten, Information Notice No. 79-01, is the first of this new form of communication.
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