ML19320D512: Difference between revisions
StriderTol (talk | contribs) (Created page by program invented by StriderTol) |
StriderTol (talk | contribs) (StriderTol Bot change) |
||
| (One intermediate revision by the same user not shown) | |||
| Line 16: | Line 16: | ||
=Text= | =Text= | ||
{{#Wiki_filter: | {{#Wiki_filter:% | ||
TOLEDO EDISON A>ckuC P C ACUSE Docket No. 50-346 | TOLEDO EDISON A>ckuC P C ACUSE Docket No. 50-346 llL[7"" | ||
14 t 91259-5221 License No. NPF-3 Serial No. 628 July 14, 1980 Director of Nuclear Reactor Regulation Attention: Mr. Robert W. Reid, Chief Operating Reactor Branch No. 4 Division of Licensing United States Nuclear Regulatory Commission Washington, D. C. 20555 | 14 t 91259-5221 License No. NPF-3 Serial No. 628 July 14, 1980 Director of Nuclear Reactor Regulation Attention: | ||
Mr. Robert W. Reid, Chief Operating Reactor Branch No. 4 Division of Licensing United States Nuclear Regulatory Commission Washington, D. C. | |||
20555 | |||
==Dear Mr. Reid:== | ==Dear Mr. Reid:== | ||
By {{letter dated|date=January 20, 1978|text=letter dated January 20, 1978}}, Mr. Victor Stello, Jr., of the NRC staff, requested of all PWR licensees "an evaluation of the overall asymmetric loss of coolant accident (LOCA) loads". | |||
By letter dated January 20, 1978, Mr. Victor Stello, Jr., of the NRC staff, requested of all PWR licensees "an evaluation of the overall | |||
asymmetric loss of coolant accident (LOCA) loads". | |||
The Toledo Edison Company has participated jointly with other Babcock & | The Toledo Edison Company has participated jointly with other Babcock & | ||
Wilcox NSSS owners in a multiphase program to evaluate the effects of asymmetric LOCA loads at Davis-Besse Nuclear Power Station Unit 1. An interim generic report entitled, BAW 1597, " Effects of Asymmetric LOCA Loadings - Phase II Status" was submitted to your staff by Babcock & | Wilcox NSSS owners in a multiphase program to evaluate the effects of asymmetric LOCA loads at Davis-Besse Nuclear Power Station Unit 1. | ||
Wilcox on February 14, 1980 and endorsed by letter from Toledo Edison dated February 15,1980 (Serial No. 593) . | An interim generic report entitled, BAW 1597, " Effects of Asymmetric LOCA Loadings - Phase II Status" was submitted to your staff by Babcock & | ||
Wilcox on February 14, 1980 and endorsed by letter from Toledo Edison dated February 15,1980 (Serial No. 593). | |||
Toledo Edison has completed its review of the final Phase 11 report prepared by Babcock & Wilecx entitled, BAW-1621, " Effects of Asymmetric LOCA Loadings - Phase II Analysis". This report was transmitted to you by letter from Mr. J. H. Taylor of Babcock & Wilcox on July 1, 1980. | Toledo Edison has completed its review of the final Phase 11 report prepared by Babcock & Wilecx entitled, BAW-1621, " Effects of Asymmetric LOCA Loadings - Phase II Analysis". This report was transmitted to you by letter from Mr. J. H. Taylor of Babcock & Wilcox on July 1, 1980. | ||
Two specific areas relating to Davis-Besse Unit I that deserve high-lighting include: | Two specific areas relating to Davis-Besse Unit I that deserve high-lighting include: | ||
1) | |||
THE TCLEDO EDISON COMPANY | Section 12.1 evaluates the service support structure platform-to-cavity wall connection. To ensure the applicability of the evaluation results, the required clearances of 1.0 inches are | ||
'b d)h) being provided.as part of a modification currently being made to the structure. This modification will be completed prior to startup from the current refueling outage. | |||
k2 i | |||
THE TCLEDO EDISON COMPANY EDISON PL ZA 300 MACISON AVENUE TCLEDO. CHlO 43652 eo o7210 45'/ | |||
/ | |||
'o | |||
, 2) | |||
This report, in conjunction with the observations above, provide an acceptable demonstration of the ability of Davis-Besse Nuclear Power Station Unit 1 to maintain core coolability, even for the asymmetric | Section 11.4 is an evaluation of unbroken primary system piping. To provide the evaluation, a simplistic subcompartment pressurization model was utilized to analyze stress imposed on other reactor coolant system piping located within the same steam generator compartment as the assumed break. This basic linear calculation was run without taking any credit for reactor coolant pump wire rope supports or initial pipe movement through the pipe support gaps. The results were compared directly against standard code allowable stresses. All loca-tions except one fell well within code allowable limits by this methodology. | ||
loading effects for extremely unlikely loss of coolant accidents. This completes Toledo Edison's response to your letter of January 20, 1978. | In reviewing the analysis with B&W the conservatisms and symplistic approach provide assurance that the results for the one remaining stress location would be acceptable given a more detailed, specific analysis. | ||
This report, in conjunction with the observations above, provide an acceptable demonstration of the ability of Davis-Besse Nuclear Power Station Unit 1 to maintain core coolability, even for the asymmetric loading effects for extremely unlikely loss of coolant accidents. This completes Toledo Edison's response to your letter of January 20, 1978. | |||
Very truly yours, ff h= | Very truly yours, ff h= | ||
RPC/JKW jh d/4-5}} | RPC/JKW jh d/4-5}} | ||
Latest revision as of 03:01, 1 January 2025
| ML19320D512 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 07/14/1980 |
| From: | Crouse R TOLEDO EDISON CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| 628, NUDOCS 8007210454 | |
| Download: ML19320D512 (2) | |
Text
%
TOLEDO EDISON A>ckuC P C ACUSE Docket No. 50-346 llL[7""
14 t 91259-5221 License No. NPF-3 Serial No. 628 July 14, 1980 Director of Nuclear Reactor Regulation Attention:
Mr. Robert W. Reid, Chief Operating Reactor Branch No. 4 Division of Licensing United States Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Reid:
By letter dated January 20, 1978, Mr. Victor Stello, Jr., of the NRC staff, requested of all PWR licensees "an evaluation of the overall asymmetric loss of coolant accident (LOCA) loads".
The Toledo Edison Company has participated jointly with other Babcock &
Wilcox NSSS owners in a multiphase program to evaluate the effects of asymmetric LOCA loads at Davis-Besse Nuclear Power Station Unit 1.
An interim generic report entitled, BAW 1597, " Effects of Asymmetric LOCA Loadings - Phase II Status" was submitted to your staff by Babcock &
Wilcox on February 14, 1980 and endorsed by letter from Toledo Edison dated February 15,1980 (Serial No. 593).
Toledo Edison has completed its review of the final Phase 11 report prepared by Babcock & Wilecx entitled, BAW-1621, " Effects of Asymmetric LOCA Loadings - Phase II Analysis". This report was transmitted to you by letter from Mr. J. H. Taylor of Babcock & Wilcox on July 1, 1980.
Two specific areas relating to Davis-Besse Unit I that deserve high-lighting include:
1)
Section 12.1 evaluates the service support structure platform-to-cavity wall connection. To ensure the applicability of the evaluation results, the required clearances of 1.0 inches are
'b d)h) being provided.as part of a modification currently being made to the structure. This modification will be completed prior to startup from the current refueling outage.
k2 i
THE TCLEDO EDISON COMPANY EDISON PL ZA 300 MACISON AVENUE TCLEDO. CHlO 43652 eo o7210 45'/
/
'o
, 2)
Section 11.4 is an evaluation of unbroken primary system piping. To provide the evaluation, a simplistic subcompartment pressurization model was utilized to analyze stress imposed on other reactor coolant system piping located within the same steam generator compartment as the assumed break. This basic linear calculation was run without taking any credit for reactor coolant pump wire rope supports or initial pipe movement through the pipe support gaps. The results were compared directly against standard code allowable stresses. All loca-tions except one fell well within code allowable limits by this methodology.
In reviewing the analysis with B&W the conservatisms and symplistic approach provide assurance that the results for the one remaining stress location would be acceptable given a more detailed, specific analysis.
This report, in conjunction with the observations above, provide an acceptable demonstration of the ability of Davis-Besse Nuclear Power Station Unit 1 to maintain core coolability, even for the asymmetric loading effects for extremely unlikely loss of coolant accidents. This completes Toledo Edison's response to your letter of January 20, 1978.
Very truly yours, ff h=
RPC/JKW jh d/4-5