ML19329B099
| ML19329B099 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 04/12/1976 |
| From: | Roe L TOLEDO EDISON CO. |
| To: | |
| Shared Package | |
| ML19329B100 | List: |
| References | |
| NUDOCS 8001300684 | |
| Download: ML19329B099 (3) | |
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FIOM OATE 08 DOCUMENT DATE RECElvfD NO h TM EDISON CGEPM 4/12/76 4/21/76 60382 LTR.
MEMO REPORT OTHER I
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on G-CC OTHER X
II (. ROT )
0 Co Cuaat~Ca O
o A ~s**a 'o ACTiO~ NECESsARv i
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NO ACTION NECESSARY ev CLASSir.
Post OFFsCE F'LE CCOE U
REG NO DESCR PTION %st 6e Unceseshess3 REFERRED TO DATE AECElvf D sv GATE INTERIM REPORT DATED AUGUST 13, 1975
' REGARDING THE DEFICII2tCT REIATED TO g[//)
[_V R.A. HARTTIELD DAVIS-5F.SSI NOCLEAR PCWER STATION UNIT
-ox ic h n Lure NO.1 REACTOR C00LAlff PUMPS.
ENCLOSURES C0FIES FOR PCR, LOCAL POR, NSIC, AND CTIE SENT TO RIGICHAL COCEDINATCR FGL DISTRIBUTION.
RawARas COPT SENT TO REGI0tt III 1
V S NUCLEAN REM;LATORY CCMu+5SION FCPV *.AC LYS 0h$
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April 12, 1976
\\02.3 L2i4ILJ0weG Docket No. 50-346 LOWELL E. ROE Vice President Facd ties C~e'CDment Dr. Donald F. Knuth, Director uiss es,.s2.a Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D. C.
20055
Dear Dr. Knuth:
This letter is submitted in accordance with 10 CFR 50.55 as consummation of the Toledo Edison Interim Report, dated August 13, 1975, regarding the apparent deficiency related to Davis-Besse Nuclear Power Station Unit No.1 reactor coolant pumps lAl, lA2, and 1B1.
Description of the Deficienev
' Indications exceeding the manufacturer's acceptance standards utilizing ASME Section III 1968 Edition for Class A vessels were discovered during the baseline inspection in the casing welds of Byron Jackson-furnished reactor coolant pumps lAl, lA2, and 131. The specific indications noted were:
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R. C. Pump Baseline Inspection Identifica tion Radiographic Review Comments lAl View E25-E26; Crack-type indication
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lA2 View A28-B28, slag or non-fusion approximately lk" long.
1B1 View A2-A3, slag approximately s
7" long Corrective Action Taken The indications were re=oved and the cavities examined by the liquid penetrant and radiographic methods to ensure defect removal. The cavities were then rewelded and the repaired areas reexamined by radiographic and liquid penetrant methods. The repaired areas were then radiographed by the Inservice Inspection Group to esta-blish the baseline documentation. The pumps will be hydrostatically tested at the time of the reactor coolant system hydrostatic test.
Analysis of Deficiency The reactor coolant pump casing welds were radiographed during original manufacture and certified to Byron Jackson by General Electric, Schenectady, to the acceptance standards of ASME Section III 1968 Edition for Class A vessels. Following the discovery in the baseline indications, the original GE radiographs were reviewed by both GE and Byron Jackson. Their review reconfir=ed the acceptability of the original GE radiographs and the acceptability of the pump casings based on the code requirements at the time of manufacture. The original radiographs were made by GE, utilizing Type AA film.
THE TOLEDO EDISCN CCMPANY EDISON PLAZA 300 MACISCN AVENUE TOLEDO. CHIO 43652
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Page 2 April 12,~1976
.s During the baseline inspection, the radiographs were made utilizing Types 45, 55, and 65 films which provided a higher contrast than the Type t.A film.
In addition, and as noted in~IE Inspection Report :*a. 050-346/75
.'l. the GE penotraneter used for the original GE radiographs in some instances had partially masked the areas of concern on the original film. These conditions contributed to the indications not being discovered at the time of manufacture.
Safety Implications Any possible adverse safety considerations have been resolved with the timely finding, evaluating, repairing, and accepting of the three pumps' casing weld joint areas. The baseline inspection program has provided additional confidence prior to placing the reactor coolant pumps into service.
Yours truly,
,4 f'..
\\
Lowell E. Roe Vice President Facilities Development LER/jy 4
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