ML19257B611
| ML19257B611 | |
| Person / Time | |
|---|---|
| Site: | 05000273, Crane |
| Issue date: | 08/03/1979 |
| From: | Lafleur J NRC OFFICE OF INTERNATIONAL PROGRAMS (OIP) |
| To: | Gorinson S PRESIDENT'S COMMISSION ON THE ACCIDENT AT THREE MILE |
| References | |
| TASK-TF, TASK-TMR NUDOCS 8001170778 | |
| Download: ML19257B611 (2) | |
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,j WASHINGTON, D. C. 205S5 AUG 3 1979 MEMORANDUM T0:
Stanley Gorinson Presidert's Commission on TMI FROM:
Joseph D. Lafleur, Jr., Deputy Director Office of International Programs
SUBJECT:
STATEMENT ON OVERSEAS REACTOR TRANSIENT Confirming earlier advice, I am enclosing a copy of a state-ment containing all the information we are authorized to disclose on the overseas PORV transient discussed recently.
The NRC staff is now discussing possible additional disclosures with the originator of this info tion.
Josep D.Tfleur,Jr.
Deputy Director Office of International Programs
Enclosure:
As stated cc w/ encl:
M. Rogovin W. C. Parler K. E. Cornell M. E. Chopko S. Helfman D. G. Eisenhut B. K. Grimes C. H. Berlinger S. H. Weiss S. Newberry R. H. Vollmer A. C. Thadani 9
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QUOTE. WE ARE AWARE OF ONE EVENT AT A FOREIGN REACTOR DESIGNED BY WESTINGHOUSE, WHICH OCCURRED A NUMBER OF YEARS AG0 IN WHICH A PORV WAS CHALLENGED DURING A TURBINE TRIP TRANSIENT AND FAILED TO RECLOSE WHEN PRESSURE DECREASED.
THE FAILURE TO CLOSE WAS DETECTED IN A FEW MINUTES BY THE OPERATORS, WHO IMMEDIATELY ISOLATED THE VALVE b( C10Mim THE BLOCK VALVE IN SERIES WITH THE PORV.
THIS ACTION TERMINATED THE INCIDENT.
THE FAILURE TO RECLOSE WAS DUE TO THE RUPTURE OF THE CAST-IRON FRAME BETWEEN THE VALVE OPERATER AND THE VALVE BODY WHICH WAS CAUSED BY A WATER SLUG HITTING THE VALVE. THE SOURCE OF THE WATER SLUG JAS THE LOOP SEAL LOCATED BETWEEN THE PRESSURIZER AND THE RELIEF VALVE.
INVESTIGATION OF THIS EVENT IDENTIFIED THE CAUSE OF THE VALVE FAILURE TO BE DESIGN ERROR WHICH WE UNDERSTAND)HAS BEEN SUBSEQUENTLY REMEDIED.
UNQUOTE.
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