ML19332A711
| ML19332A711 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 07/24/1980 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Cavanaugh W ARKANSAS POWER & LIGHT CO. |
| References | |
| NUDOCS 8009180145 | |
| Download: ML19332A711 (1) | |
Text
bec to DAC:ADM:
- SP E FILES
,g2 UNITED STATES PDR:HQ d'
NUCLEAR REGULATORY COMMISSION LPDR
.o nEctoN iv J
h "1 2
611 nYAN Pt.AZA DRIVE, SulTE 1000 IIC L p7' !yj snuNGToN, TEXAS 76012 fj$1C
'%l -:,d /
July 24, 1980 Decket No. 50-313 50-368 Arkansas Power and Light Company ATTN:
Mr. tJilliam Cavanaugh III Vice P ssident of Ceneration and Construction P. O. Box 551 Little Rock, Arkansas 72203 Gentlemen:
The enclosed II Bulletin No. 80-18, is forwarded for action.
A written response is required.
In order to assist the NRC in evaluating the value/ impact of each Bulletin on licensees, it would be helpful if you would provide an estimate of the manpower expended in conduct of the review and preparation of the report (s) required by the Bulletin.
Please esti:nate separately the manpower associated with correc-tive actions necessary following identification of problems through the Bulletin.
If you desire additional information regarding this matter, please contact this office.
Sincerely, f.?'1 V. h h ~ f, O
?
{
u, Kar Seyfrit Director I
Enclosures:
1.
II Bulletin No. 80-18 2.
List of Bulletins Recently Issued cc: James ?. O'Hanlon, Plant Manager Arkansas Nuclear One P. O. Box 608 Russellville, Arkansas 72801 i
8009180 #5 9
1 SSINS No.
6820 Accession No.:
UNITED STATES 8005050062 i
NUCLEAR REGULATORY COMMISSION 0FFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 IE Bulletin No. 80-18 l
Date:
July 24, 1980 Page 1 of 3 MAINTENANCE OF ADEQUATE MINIMUM FLOW THRU CENTRIFUGAL CHARGING PUMPS FOLLOWING SECONDARY SIDE HIGH ENERGY LINE RUPTURE Description of Circumstances:
Letters similar to the May 8, 1980 notification made pursuant to Title 10 CFR Part 21 (enclosure) were sent from Westinghouse to a number of operating plants and plants under construction (list, within enclosure) in early May, 1980.
The letters and the enclosed "Part 21" letter contain a complete description of the potential problem summarized below. The letters indicated that under certain conditions the centrifugal charging pumps (CCPs) could be damaged due to lack of minimum flow before presently applicable safety injection (SI) termination criteria are met. The particular circumstances that could result in damage vary somewhat from plant to plant, but involve unavail-ability of the pressurizer power operated relief valves (PORVs), with operation of one or more CCPs repressurizing the reactor during SI following a secondary system high energy line break. Since the SI signal automatically isolates the CCP mini-flow return line, the flow through the CCPs is determined by the individual pump characteristic head vs. flow curve, the pressurizer safety valve setpoint, and the flow resistances and pressure losses in the piping and in the reactor core. That minimum flow may not be adequate to insure pump cooling, and resulting pump damage could violate design criteria be# ore current SI termination criteria are met.
Westinghouse recommends that plant specific calculations outlined in the letter (enclosure) be performed to decermine if adequate minimum flow is assured under all conditions. If adequate minimum flow is not assured, Westinghouse recommends specific equipment and procedtire modifications which will result in adequate minimum flow. The recommended modifications assure availability of the necessary minimum flow by assuring that the mini-flow bypass line will be open when needed, but will be closed at lower t
i bypass line closure might be DUPLICATE DOCUMENT Entire document previously entered into system under:
ANO h
No. of es:
_