ML19247B269
| ML19247B269 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/29/1979 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Cavanaugh W ARKANSAS POWER & LIGHT CO. |
| References | |
| NUDOCS 7908080276 | |
| Download: ML19247B269 (1) | |
Text
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.....f Docket No.: 50-313 Mr. William Cavanaugh, III Vice President, Generation and Construction Arkansas Power & Light Company P. O. Box 551 Little Rock, Arkansas 72203
Dear Mr. Cavanaugh:
By letter dated April 20, 1979, we provided our Safety Evaluation supporting stud tensioning at 70 F at Arkansas Nuclear One, Unit flo.1 (ANO-1).
In conducting our review for this issue we ident1fied two issues which require our attention. They are the following:
1.
In your letter of Auguso 18, 1978, you indicated that efforts were being formulatec, detemine the actual chemistry of the ANC-1 closure head weld. We requs, tre plcns for this task or otnenvise report if the job has been abandoted.
2.
In addition to the stud tensioning at 70 F problem there are other safety analyses involving atypical weld metal to be considered. Other plant operations, such as nomal operation, heat-uo, cool-down, hydrostatic testing (ASME Code requirement), etc., also are subject to fracture prevention limitations. Charpy tests of atypical weld metal snowed that the ductile upper shelf occurred at about 3C0 F where the average abscri.cd energy was about 81 f t.-lb.
Those results suggest that there is no need to impose additional operating limitations on ANO-1 to prevent failure of the reactor pressure vessel. However, as was the case with the stud tensioning problem, there is greater technical confidence in showing trat tnere is an adequate safety margin by virtue of a fracture mec6 ics analysis using ex;:erimental fracture toughness data obtained the tempera-ture of interest. Therefore, we request you obtain and report elevated temperature K*c (cr JIc) data.
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We recuest a schedule for your response which will provide the requested data as secn a; practicable.
Sincerely, h& Uwj
'de Rccert W.
Reid, Chief Operating Reactors Branch 61 Divisicn of Opcrating Reactors cc: See next page bbc
- 30 799g080
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Arkansas Power & Light Company cc:
Phillip K. Lyon, Esq.
House, Holms & Jewell 1550 Tower Building Little Rock, Arkansas 72201 Mr. David C. Trimble Manager, Licensing Arkansas Power & Light Company P. O. Box 551 Little Rock, Arkansas 72203 Mr. James P. O'Hanlon Genera' Manager Arkt..sr.s Nuclea-One P. O. Box 6CS Russellville, Arkansas 72801 Mr. William Johnson U. S. Nuclear Regulatory Commission P. O. Box 2090 Russellville, Arkansas 72801 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 420, 7735 Old Georgetown Road Bethesda, Maryland 20014 Troy B. Conner, Jr., Esq.
Conner, Moore & Corber 1747 Pennsylvania Avenue, N.W.
Washington, D.C.
20006 Arkansas Polytechnic College Russellville, Arkansas 72501 c: 'i b Ll' L
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