ML19253C197
| ML19253C197 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 11/16/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Nichols T SOUTH CAROLINA ELECTRIC & GAS CO. |
| References | |
| NUDOCS 7911300138 | |
| Download: ML19253C197 (1) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION
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'l 101 MARIETTA ST N.W.. SUITE 3100 ATl.ANTA, GEORGIA 30303 NOV 161979 In Reply Refer To:
RI 0-395 South Carolina Electric and Gas Company Attn:
T. C. Nichols, Jr., Vice President Power Production and System Operations Post Office Box 764 Columbia, South Carolina 29218 Gentlemen:
The enclosed IE Information Notice No. 79-27 provides information with regard to the sequence of events that followed incidents involving steam generator tube ruptures at two P'n'R units.
Sincerely, y.,.
James P. O'Reill' Director
Enclosures:
1.
IE Information Notice No. 79-27 2.
List of IE Information Notices Issued in the Last Six Monthe 1443 T31 IS9 7011300
SSINS No.:
6870 Accession No.:
7910250488 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON D.C.
20555 November 16, 1979 IE Information Notice No. 79-27 STEAM GENERATOR TUBE RUPTURES AT TWO PWR PLANTS Description of Circumstances:
In recent months two incidents involving steam generator tube ruptures have occurred.
In both instances, the units were cooled down and placed in the residual heat removal mode with existing procedures.
Event of June 25, 1979, at the Doel 2 Nuclear Power Plant in Belgium The first event occurred on June 25, 1979, at the Doel 2 nuclear power plant in Belgium. The Doel unit is a 390 Mwe Westinghouse two-loop reactor. The event consisted of a rupture of several tubes in the loop B steam generator. The resultant leakage between the primary and secondary systems was estimated to be 125 gpm. The event started when the plant was heated up after a shutdnwn caused by a malfunction of the main steam isolation valve.
At the time of the incident the primary coolant pressure was 2233 psi and the temperature 491 F.
The reactor remained subcritical throughout the event.
The first indication of abnormal behavior was a rapid decrease of the primary system pressure (approximately:
28 psi / min.).
This was followed by the sequence of events listed below:
Time, min.
1.
Increase of charging flow demand, charging pump.
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