ML20151U684
| ML20151U684 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 03/31/1977 |
| From: | Roy G, Thompson D, Warnick R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-77-050, PNO-77-50, NUDOCS 9809110121 | |
| Download: ML20151U684 (2) | |
Text
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I PRELIMINARY NOTIFICATION March 31, 1977 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE-PNo-77-50 This preliminary notification constitutes EARLY notfice of an event of POSSIBLE safety or public interest significance....Theinformation i
, presented is as initially received without-verification or evaluation l
and is basically all that is known by IE staff on_this date.
l Facility Iowa Electri'c Light and Power Company,. Duane Arnold Energy Center, (DN 50-331), Palo, Iowa
Subject:
AUTOMATIC PRESSURE RELIEF VALVE 1 FAILURE.L.=
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.~.m Iowa Elect?ic Light and Power Company notified Region III (Glen Ellyn) of-
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failure of four of six automatic relief valves during testing. The halves
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had been removed from the reactor's main steam line and were undergoitig'a ~~
l bench test and reset at Wylie En51neering in Hunt'aville, Alabama. On
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M rch 29, 1977, one of the six valves lifted at 1125 psi (Technical i
Specification limit is 1100 + 11 ' psi), but reset at a higher 1
than design pressure (design reset is 50 psi).
All six valves could be operated manually-and.the-four valves associated.
with the Automatic Depressurization System (ADS) would' have performed their ADS function. The licensee has stated that the manual relief function of the six valves had been satisfactorily tested at the site.
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y There are two spring-loaded safety valves in addition to the six relief valves. One was tested satisfactorily during the last refueling outage while the other will be tested during the current refueling outage. Two i
licensee. representatives _have bean dispatched to.Huntsville, Alabama.to i
observe the testing of the final two relief valves. The four relief l
valves which failed the testing have been disassembled. No apparent cause-1 of failure has been ascertained at this time.
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The valves are Dresser Industries 6" pneumatically operated relief i
valves.
Region III is following this matter closely.
No press releases by the licensee or Region III (Glen Ellyn) are being issued. This communication is being forwarded because of the history of operating problems with BWR relief valves.
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Continued Oj
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'h 0 9809110121 770331 PDR I4 E q
PNO-77-050 PDR
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PNO-77-50 Continued March 31, 1977 Region III (Glen Ellyn) received notification of this occurrence by-telephone on March 29, 1977, and again on March 30, 1977. This PN is current as of 0900 March 31, 1977.
Contact:
RFWarni'ck, IE x27261 GWRoy, IE x27261 DThompson, IE x27541 Distributi_on: TransmittedHSt#.'3kP.
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Chairman Rowden C. C. Kammerer, CA G. F. Murphy, JCAE Commissioner Gilinsky S. J. Chilk, SECY H. H. Whiteside, SCNR i
H. R. Myers, HCEE Transmitted: HNBB8.'8d i
p PBldgI/;V6h SS Bldg O W a..
L. V. Gossick, EDO B. C. Rusche,' NRR K. R. Chapman, NMSS S. H. Hanauer, EDO H. K. Shapar, ELD J. A. Harris, PA l
W. G. Mcdonald, MIPC Luge (MAIL)
E. Volgenau, IE R. G. Ryan, OSP T. J. McTiernan, Region g J.'s'u,e FREL1m NAlu Nuuntauva
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