ML17303B105
| ML17303B105 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 04/29/1988 |
| From: | Crutchfield D Office of Nuclear Reactor Regulation |
| To: | Miraglia F Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8805120253 | |
| Download: ML17303B105 (4) | |
Text
MEMORANDUM FOR:
FROM:
SUBJECT:
April 29, 1988 gy-s~5
'I 88051 QQp53 Frank J. Miraglia, Jr.
PDR ADOCg Associate Director for Projects Office of Nuclear Reactor Regulation Dennis M. Crutchfield, Director Division of Reactor Projects - III, IV, V and Special Projects Office of Nuclear Reactor Regulation PALO VERDE UNIT 2 SHAFT CRACKING RESULTS 880029 050005@9 PDR ~
Results of RCP shaft cracking measurements on Palo Verde 'Uni.t 2 were discussed with the licensee via conference call on April 28.
Table 1 attached shows the depth measurements.
The licensee made the following, points during the conversation:
1.
The quantity of cracks found on Unit 2 is less than that experienced on Unit l.
2.
The Unit 2 data does not indicate a different.root cause.
3.
While the 12.7 mm depth crack on the 2A pump is somewhat surprising, it is not totally unexpected.
The deepest crack on a Unit 1 pump.was 15.2 mm.
4.
After 1 1/2 years of operation, the licensees feel that the cracks on the Unit 2 RCP shafts are minor.
The staff concurs with the licensees'indings and does not feel that changes to the Unit 3 vibration monitoring <<program.are necessary at this time..
No interruption of Unit 3 operation for RCP shaft inspection is necessary at this time.
Furthermore, the licensee stated that information from German plants indicates that the removal of chrome from.'high stress areas appears to have fixed the problem.
This information will be forwarded to theosta~f
~f~~QQy.,
I Dennis N. Crotchfield, Director
- Division of Reactor Projects, - III, IV, V and Special'rojects Office of Nuclear Reactor Regulation
Contact:
M. Davis, 'NRR/DRSP 492-1368 DISTRIBUTION NRC 8
LPDRs PD5 Reading DMCrutchfield
- GMHolahan
- PREVIOUSLY CONCURRED DRSP/PDV*
NRR/DEST*
MJDavis:dr L'Shao 4/29/88 4/29/88 GWKnighton, MJDavis JLee LShao DRSP/D:PDV+
GWKnighton 4/29/88 GMHo ahan 4/IJ/88 DMCrutchfield 4/pq/88
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ENCLOSURE TABLE 1 Pump Number Approximate Hours Operation Keyway Depth millimeters Measurement Method 1A 1B 2A 2B 15,900 15, 800 15,200 15,100 0
180 pO 180 pO 180 pO 180 0
- 1. 6*
0 12.7 1.6 1.6 Wet fluorescent magnetic particle exam (MT) downside of keyway
- Dimension shown is the length of the indication along the side of the keyway.