ML19269B942
| ML19269B942 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 01/16/1979 |
| From: | Roe L TOLEDO EDISON CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7901190080 | |
| Download: ML19269B942 (2) | |
Text
TOLEDO
%=> EDISON Docket No. 50-346 LOWELL E. ROE
%cc Pres + dent Operating License No. NPF-3
(([*ll[*"
Serial No. 481 January 16, 1979 Director of Nuclear Reactor Regulations Attention:
Mr. Robert W. Reid, Chief Operating Reactors Branch No. 4 Division of Operating Reactors United States Nucl c Regulatory Commission Washington, D.C.
0555
Dear Mr. Reid:
In our letter to you on May 26, 1978, Serial No. 439, we agreed to remeasure the reactor coolant system flow rate af:er removal of the burnable poison rod assemblies (15PMAs) and orifice rod acsemblies (ORAs),
and to supply information on flow data and total pressure drops, as required in Davis-Besse Unit 1 operating license NPF-3, Condi-tion 2.C. (3)(1), Amendment 7.
The information in this letter revises the results obtained before the removal of the BPRAs and ORAs, which were supplied in our letter dated April 24, 1978, Serial No. 428.
The four-pump flow rate after removal of the BPRAs and ORAs was 149.75 million pounds per hour or 403,300 gallons per minute at the cold leg.
This is 114.6% of the design flow rate for four-pump operation. The design flow rate is 352,000 gallons per minute for four-pump operation.
The measurement was determined from heat balance data taken at 100% of rated thermal power. The uncertainty on the result is 2.09%.
(This uncertainty was obtained on page 25 of Attachment 1 to Toledo Edison Company letter dated May 26, 1978, Serial No. 436. The value of 12.09%
corresponds to the heat balance data only and doeu not include the uncertainty from the Gentile flow rates.)
In the analysis of the reactor coclant system total pressure drop the averaged reactor coolant pump head-flow (H-Q) curve was used.
This curve was determined from hot performance data taken with each of the four Davis-Besse pumps. From this curve and from the flow rate and uncertainties, the results shown in the following tsole were obtained.
'hb THE TOLEOO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO. OHlO 43652 i
a System Pressure Drop (Feet)
Flow Rate After BPRA and Before BPRA and Condition ORA Removal ORA Removal Measured Flow Rate 334 338 Measured Flow Race 326 331 Plus Uncertainty Measured Flow Rate 342 344 Minus Uncertainty Results before BPRA and ORA removal, as given in our April 24, 1978 letter are also shown in the above table.
The measured flow rate for the information given in the April 24, 1978 letter was determined from heat balance data taken at 90% power. A flow rate equal to (113.4 2)
% of the design flow rate was obtained.
It should be noted that the uncertainty on this value was revised by the analysis given in our letter on May 26, 1978, Serial No. 436.
Toledo Edison considers the above information to be a sufficient and satisfactory response to the commitment in our May 26, 1978 letter to supply additional information on flow daca and total pressure drops.
Yours very truly,
' t&
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