ML19312C865
| ML19312C865 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/22/1972 |
| From: | Desiree Davis US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Deyoung R US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8001130027 | |
| Download: ML19312C865 (4) | |
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UtHTED STATES Rf ', :s., / h ATOMIC ENERGY COMMISSION
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>q CEC 2 21F/2 R. C. DeYoung, Assistant Director For Pressurized Water Reactors, L THRU:
A. Schwencer, Chief, Pressurized Water Reactors, L d'EETING WITH DUKE POWER COMPANY AND BABCOCK & WILCCX-OCONEE 2/3 CFT LINE BREAK ANALYSIS Enclosed is a summary of the veeting held on December 15, 1972 with Duke Power Company and Babcock & Wilcox. An attendance list is also enclosed.
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Donald K. 2 avis Pressurized Water Reactors Branch No. 4 Directorate of Licensing
Enclosures:
1.
Meeting Summary 2.
Attendance List cc:
R. S.,Boyd D. Skovholt.
D. Knuth R. Mriccary R. Tedesco H. Denton PWR Branch Chiefs V. Stello 6
R. W. Klecker M. Rosen R0 (3)
AEC participants AEC PDR I. A. Peltiec Local PDR l'
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ENCLOSURE 1 e
SUMMARY
OF MEETING WITH DUKE POWER COMPANY AND BALCOCK & WILC OCONEE 2/3 CFT LINE BREAK ANALYSIS 7ecember 15, 1972 Sunmary_
In this meeting the preliminary results of the staff's independent hydraulics calculations of a break in the CFT line for the Oconee The staff's calculations were compared to several plants were presented.
models B&W proposed for this accident.
Some unique features of ECCS for the Oconee Units were presented which potentially could reduce the consequences of this accident. The heat transfer methods which should be used to evalute the cladding temperature resulting from this accident were discussed.
)
Staff's Independent Calculation Messrs. Ross and Sullivan of the Reactor Systems Branch ' resented p
the available results f rom eleven RELAP-3 (Mod 62) cases which were instituted to investigate the modeling sensitivity of this The number of nodes in the system was varied as well as the break.
(homogeneous or " babble rise") of nodes in the down-number and type One case also varied the size of the break to investigate comer.
No definitive the effect of a proposed orifice in the CFT line.
conclusion on the appropriate hydraulics model was reached since most of these results are still under active review.
I 1
Oconee ECCS_
The dif ferences between Oconee's ECCS and typical B&W plant ECGS were discussed. These differences are 1) large capacity emergency power supplies, 2) three LPI pumps instead of two and 3) a cross connection of these LPI pumps. The result of these differences appeared to enable Oconee to have, as a minimum, 2 HPI pumps and one CFT to mitigate the consequences of this accident assuming that. two valves in the LPI crossover, presently locked closed, are changed to the locked open position.
Subsequent evaluation and conversation with Duke Power have shown that the failure of a single power supply would still degrade the ECCS to one HPI I
' pump and one CFT.
Heat Transfer The staff indicated that using Schrock-Grossman heat transfer coefficients was not appropriate lor the heat up calculations of this transient.
Based on GE data which present core cooling ability versus quiet water level in the bundle, a heat transfer model which considers steam cooling above the core water level would appear more appropriate.
Both the sta'f and B&W agreed to pursue this approach *in the next several weeks.
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ENCLOSURE 2 o
Attendance List t
December 15, 1972 H. Sullivan D. Ross R. Mattson*
A. Schwencer*
D. Davis P. Norjan*
B&W J. F. Mallay*
L. R. Allen J. E. Mecca L. R. Pletke*
B. M. Dunn
.C. E. Parks Duke Power Company Ken Canady*
- Part-time attendance l
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