ML19326B699
| ML19326B699 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 07/05/1974 |
| From: | Cavanaugh W, Phillips J, Reuter D ARKANSAS POWER & LIGHT CO. |
| To: | |
| Shared Package | |
| ML19326B689 | List: |
| References | |
| NUDOCS 8004170538 | |
| Download: ML19326B699 (3) | |
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Abnormal Occurrence Report No. 50-313/74-12 2.
Report Date:
11/18/74 3.
' Occurrence Date:
11/9/74
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4.
Facility:
. Arkansas Nuclear One-Unit 1 Rus_sellville, Arkansas PDT-1035, PDT-1037, and PT 1039 Identification of Occurrence:
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Reactor Protection System (RPS) instrument line socket weld failure.
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- 6. -Conditions Prior to Occurrence:
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Reactor Power 0
MWth Steady-State Power i
Hot. Standby Net Output 0
MWe Cold Shutdown X
Percent of Full Power 0
4 Refueling Shutdown Routine Startup Operation Routine Shutdown Operatio.n Load Changes During Routine Power peration Other (Specify) 2 1'
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Description of Occurrence:
During a routine operator inspecfion at 1900 hours0.022 days <br />0.528 hours <br />0.00314 weeks <br />7.2295e-4 months <br /> on 11/9/74, boric acid crystals were noticed near the three socket welds between isolation valves RC-1039B, RC-1035B and RC-1036B, and instruments PT-1039, PT-103.5 and PDT-1037 respectively. 'these are RPS instrumentation lines (3/8" 0.
and 1/4" ID) on B RCS hot leg.
A 12S psig air test was conducted on the three socket weld couplings following removal and only one was found to be leaking through a pin-Further examination will be conducted to determine hole in'the weld.
if all three welds were leaking or if boron crystals were deposited ort two welds from spray from the leaking weld.
I-004170j3I 8
July S, 1974 NSP-10, Rev. 0
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Sheet 2 l-50-313/74-12 Abnormal Occurrence Report No.
- 8. - Designation of Apparent Cause of Occurrence _:
Procedure Design
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Unusual Service
-Manufacture Condition Including-Environmental Installation /
f Construction-Component Failure Opere. tor Other (Specify)
Not determined at this time.
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Analysis of Occurrence _:
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At the time of the occurrence the reactor was at co
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'Ihere were no safety implications or hazard to the hea t fication safety of plant personnel or the public due to prompt identi tion.
and corrective action.
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- 10. Corrective Action:
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i A section of the tube 6" on either side of the socket weld c were removed and replaced with a new coupling.
at 2285 psig did not reveal any defects.
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Page 2 of.3l NSP-ID, Rev. O July 5, 1974
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' Sheet 3 Abnormal Occurrence Report No.
'50-313/74-12 11.
Failure Data:
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No prior failures of this type. Couplings are being given a metal -
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'lurgical examination. These results will be submitted in a follow-up report.
s 12.
Reviews and Approvals:
Reviewed and Approved by: Plant Safety Committee Yes (x)
No ( )
Plant Superintendent Yes (X)
No ( )
Reference:
JWA-667 Date: 11/18/74 Date: #
77[
Reviewed by:
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Licensing Supervisor
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Date: // Y 6' M Approved by:
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afet R'eview mmi ee 1
Date: h 7
Approved by: A [
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' 'unager of ucearServic[
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Approved byr
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Date: /[- / / '/
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Director of Power P oduction
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/o Date:
Approved by:
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Senior'Vice President
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l July 5, 1974 NSP-10, Rev. O Page 3 of 3