ML13308B483
| ML13308B483 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 11/08/1976 |
| From: | Ottoson H SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| RO-76-09, RO-76-9, NUDOCS 8103060504 | |
| Download: ML13308B483 (1) | |
Text
.7-
- LICENSEE EVENT REPORT CONTROL BLOCK:
(PLEASE PRINT ALL REQUIRED INFORMATION) 1 6
LICENSEE LICENSE EVENT NAME LICENSE NUMBER TYPE TYPE
]L I clAI S1 01S I I 0
0
-1001 01 01 4 I 111111
[L Ii 789 14 1525 26 30 31 32 REPORT REPORT c
t fY TYPE IOURsE DOCKET NUMBER EVENT DfA 5
fpuRT 0
A 7(
~E ECONT DIPl LT LJ 1 5I 01-10121 01 6 LiLLP...L11 71 6 LU 0 7
8 57 58 59 60 61 (A8 69 74 75 80 EVENT DESCRIPTION During the refueling outage which began on September 30, 1976, remote Ivisual examinations of the reactor vessel internals were conducted d part of aroutinel 7 8 9inspection program. *The examinations were performed utilizing a standard underwater so Srlevision sstem wi al minations recorded on a video-tave to provide a Permanent
- 7.
9record of the inspections.
The results of the visual examinations indicate that four 80 M
f t ix fltxure suppor _ natpd at the top of the thermal shield have failed-.A1.
7 f
oqzutparae u
at 80 7 13 hrza lengthowof th lxres. oThe six1 exure oare4 ituated arundThef cr br-SO 80 7 9 12 X Reo Po X
7 89 t_'.INENT COMPONffNT COMPONENT CUE LSui DLIER MANUFACTURRYR VIOLATEN 07 IR JA I E I X-1 XI X I X I WjLN 11L 2j 0L2.
7 8 910 11 12 17 43 44 47 48 CAUSE DESCRIPTION
[~~
The flexures failed because of cycle fatigue related to dynamic oscillations of the 7 8 9thermal shield causebc a
tiow induced vibration.
1ai2ure ot 13lex s
80 9Ihad no adverse effects on the thermal shield and the remainder of the reactor 7 8 9internal structures.
Therefore, the flexures will be left-in the reactor vesse-T so
[M1~ Ln their rwjrrpnt condition, 1
7 8I9 80 FAILITY METHOD OF SATUS POvER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTIN i
l 1010101 NA J
I S1 visual inspection 7 8 9
10 1213 44 45 46 80 FORM OF ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE Do I A
I'INA I
L NA 7 8 9
10 11 44 45 8o PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION 1
ID 1
_j I NAI 7 8 9 11 12 13 80 PERSONNEL INJURIES NUMBER DESCRIPTION 7
L'J 1 0e1 NA 7
9 9 1
1 so OFFSITE CONSEQUENCES Fn5]
NA 7 8 9 LOSS OR DAMAGE TO FACILITY PI PE DESCRIPTION 8
I II NoneI 7 8 9 10 80 PUBLICITY 1 I Event released to standard publicity list.
7 8 9 80 ADDITIONAL FACTORS (Event description-continued)
E0l at 210, c50 2050, and 3250, were found failed. Since the flexure failures had no
? 6 9adverse effects on the remainder of the reactor internals structures, the flexures 80 will be left in the reactor in their current condition. Licensee Event Report No.769 7 Us 80 NAME L L. Ottoson 714-492-7700 gi 6 PHONE:.7-49-70