ML19343B816
| ML19343B816 | |
| Person / Time | |
|---|---|
| Site: | Zimmer |
| Issue date: | 12/17/1980 |
| From: | Borgmann E CINCINNATI GAS & ELECTRIC CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, QA-1371, NUDOCS 8012300609 | |
| Download: ML19343B816 (2) | |
Text
7 THE CINCINNATI GAS & ELECTRIC COMPANY sE -
CINCINN ATl.CHIO 45208 a
December 17, 1980 C. A. S O RG M AN N QA~1371 St %eC# V'CE pets
- DENT U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 j
Attention:
Mr. James G.
Keppler
]
Director RE:
WM. H.
ZIMMER NUCLEAR POWER STATION -
{
UNIT 1 - 50.55 (e) ITEM M SERVICE
_q WATER PUMP ACCELERATED WEAR -
S 5
DOCKET NO. 50-358, CONSTRUCTION j
2 PERMIT CPPR-88, W.O.
57300-957, JOB E-5590 Gentlemen:
We previously reported a potential 50.55 (e) item (M-13) involving accelerated wear of service water pump impellers.
1:?is letter will advise you that after detailed investigations we hate concluded this matter is definitely reportable under 50.55 (e).
A detailed report of our investigations, conclusions and system modifications required is being included in an FSAR revision which will be forwarded to you shortly.
The matter can be summarized as follows:
The service water pumps were designed to 4ccommodate maximum service water flows associated with worst. case LOCA situations.
Service water flows during normal non-accident conditions are less than that required to prevent internal recirculation in the pumps.
The original design made no provision to assure that internal recirculation would not occur and we believe it did occur during initial pump operation.
The. accelerated impeller wear is attributed to internal recirculation.
Flow elements and minimum flow control valves are being added to the service water system to assure the situation will 1
30/7 s I
//k) 3 em.mcq
3 To:
U.S. Nuclear Regulatory Commission December 17, 1980 Re:
Wm. H.
Zimmer Nuclear Power Station -
Page #2 Unit 1 - 50.55 (e) Item M Service Water Pump Accelerateo Wear not recur.
Redesigned pump impellers of more rugged construction with lower minimum flow capability are also being installed.
We trust that the above explanation provides an accept-able interim status report on this item.
Very truly yours, THE CINCINNATI GAS & ELECTRIC COMPANY By E. A.
BORGMANN Senior Vice President JFW: dew cc:
NRC Resident Inspector Attn:
F.
T.
Daniels WRC Office' of" Inspecti6n T Etiforcement, Washington, D.C.
G e