05000219/LER-1982-049, Forwards LER 82-049/03L-0.Detailed Event Analysis Encl

Forwards LER 82-049/03L-0.Detailed Event Analysis Encl

ML20063N772
Person / Time
Site:	Oyster Creek
Issue date:	09/24/1982
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20063N773	List: 05000219/LER-1982-049, Forwards LER 82-049/03L-0.Detailed Event Analysis Encl
References
NUDOCS 8210070178
Download: ML20063N772 (3)

LER-2082-049, Forwards LER 82-049/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
2192082049R00 - NRC Website

text

. 's

• GPU Nuclear

- 2

.!- g g7 P.O. Box 388 Forked River, New Jersey 08731 609-693-6000 Writer's Direct Dial Number:

September 24, 1982 Mr. Ronald C. Haynes, Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Dear Mr. Haynes:

Subj ect: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/82-049/03L This letter forwards three copies of a Licensee Event Report to submit Reportable Occurmnce No. 50-219/82-049/03L. We recognize this LER is not being submitted within the time limitation of Technical Specification Section 6.9.2.b(2). As reported in Reportable Occurrence No. 50-219/81-61/03I-1, dated May 25,.1982, we committed to completing our inspection of first generation snubbers by September 1982. Our emphasis was to submit a complete report, and final testing of the snubbers took place over an extended period of time. By submission of this event, we have completed that program.

Very truly yours,

~

f{ [ k Peter B. Fiedler Vice President and Director Oyster Creek cc: Dimetor (40 copies)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. ?0555 Director (3)

Office of Management Information and Program Control U.S. Nuclear Regulatory Commission Washington, D.C. 20555 NRC Resident Inspector (1)

Oyster Creek Nuclear Generating Station l Forked River, NJ 08731

( B210070178 820924 l PDR ADOCK 05000219 s

S PDR _

GPU Nuclear is a part of the General Public Utilities System g@

. . - a OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/82-49/03L Report Date September 24, 1982 Occurrence Date July 15, 1982 Identification of Occurrence Operation in a degraded mode permitted by a limiting condition for operation (Section 3.5.A.8) when seven (7) Bergen-Patterson hydraulic snubbers failed functional testing af ter being removed and replaced with certified operable spa re s . These snubbers are located in the Core Spray, Containment Spray, Shut-down Cooling, and Isolation Condenser systems.

This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9 2.b.2.

Conditions Prior to Occurrence The reactor was operating in various modes.

Description of Occurrence Prior to this occurrence, Oyster Creek had established a program to replace all first generation hydraulic snubbers manufactured by Bergen-Patterson and assure that none of the existing hydraulic anubbers contained molded polyurethane seals.

It was during the performance of this program, established per Reportable Occurrence No. 50-219/81-61/03I-1 dated May 25, 1982, that certain identified snubbers were removed and replaced with certified operable spares. Subsequently, functional tests and checks for polyurethane seals were performed. At this time, seven (7) of the removed snubbers failed their functional tests for various re asons.

The following is a listing of the seven snubbers, dates tested and location.

Release Item Snubber Serial Date Drag Lock-Up Rate

1. Location # Tested System Load Velocity Velocity 1 -19/14 Y69957 8/23/82 Core Spray Header P P P 2 -19/19 487562 8/ 12 /82 Core Spray North P F P l

3 23/6 469946 8/4/82 Containment Spray P P F South I

l

.. .* a LicIn32s Event R2psrt Paga 2 Reportable Occurrence No. 50-219/82-49/03L Release Item Snubber Serial Date Drag Lock-Up Rate

1. Location # Tested System Load Velocity Velocity 4 51/5 487557 7/15/82 Core Spray North P F F 5 51/17 F848063-F 8/12/82 Shutdown Cooling P P F 6 51/18 F93502-G 8/12/82 Shutdown Cooling P P P 7 75/22 487530 8/23/82 Isolation Condenser P F F

. B' P = Passed F = Failed These tests were performed on our Bergen-Patterson test machine which was calibrated in June of 1982.

Apparent Cause of Occurrence All removed snubbers were disassembled and inspected for mode of failure. Snubber

1. 1 failed due to the fact it contained molded polyurethane seals which were cracked. This unit would not hold fluid. Snubber #2 failed due to a high lockup velocity. This was caused by the unit poppets not seating properly. Snubber #3 failed due to a high release rate due to the unit poppets being worn. Snubber #4 failed due to a high lockup rate as well as a high release rate velocity which was caused by the unit poppets being worn and not seating properly. Snubber #5 failed due to a lower release rate; however, when disasembled, no major faults were found. The cause of failure is attributed to possible dirt in the manifold.

Snubber #6 failed when tested. It also contained molded polyurethne seals which were brittle. Snubber $7 did not lockup at all due to the poppet being worn and not seating.

Analysis of Occurrence Hydraulic snubbers are installed to limit piping movement during seismic events and during transient conditions. Another function is the ability of the piston to move freely during normal operation to compensate for thermal expansion and contraction. As a result of inoperable snubbers in the piping systems, the ability of these systems to perform their intended function during a seismic event may have been degraded.

Corrective Action All seven defective snubbers were replaced with certified operable spares. In doing so, Oyster Creek has fulfilled its commitment identified in Reportable Occurrence No. 50-219/81-61/03X-1 to replace all first generation hydraulic snubbers and to assure that none of the existing units contain molded polyurethane seals.