ML20003C380
| ML20003C380 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 04/26/1974 |
| From: | JERSEY CENTRAL POWER & LIGHT CO. |
| To: | |
| References | |
| AO-50-219-74-27, NUDOCS 8103030131 | |
| Download: ML20003C380 (2) | |
Text
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OYSTER CREEK NUCLEAR GENERATING STATION FORKED RIVER, NEW JERSEY 08731 Abnormal Occurrence Report No. 50-219/74/27 Report Date April 26, 1974 Occurrence Date April 17, 1974 Identification of Occurrence Failure of three (3) Bergen-Paterson hydraulic shock and sway arrestors, two (2) located on the main steam line and one (1) on the feedwater line, in the drywell.
This event is considered to be an abnormal occurrence reportable within ten days by virtue of personal communications with AEC Region I, Regulatory Operations.
Conditions Prior to Occurrence The plant was shut down with reactor coolant less than 212'F and preparations for refueling operations were in progress.
Description of Occurrence On April 17, 1974, an inspection was conducted of all Bergen-Paterson hydraulic shock and sway arrestor units installed in the drywell. As a result of this inspection, three units, rebuilt in September 1973 with molded polyurethane seal material, were found inoperable as determined by the absence of fluid level indication in the accumulators. The inoperable units were as follows:
Serial No.
System Elevation 487530 South Main Steam 23 Feet 487512 South Main Steam 51 Feet 587519 South Feedwater 51 Feet Apparent Cause of Occurrence None of the units have as yet been disassembled and, consequently, the failure mechanism is unknown at this time.
Analysis of Occurrence
-Had the design seismic event occurred during power operation, the restraining capabilities of these units may have been seriously impared and, consequently, de-graded the structural integrity of the steam and feedwater lines in question.
l i
T/63630/8
Abnormal Occurrence No. 50-219/74/27 Page 2 Corrective Action During the present refueling outage, we Ian to replace these units and others in the primary containment which still contain molded polyurethane seal material with units rebuilt exclusively with ethylene propylene material.
In our effort to develop a long-term solution to this problem, mechanical snubbers are being evaluated by the Generation Engineering Department as possible replacements for the hydraulic snubbers.
Failure Data Manufacturer: Bergen-Paterson Type:
HSSA-10 Serial Nos.:
487530 487512 487519 4
1 1
1
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