PNO-III-92-045, on 920908,unit Shut Down Due to High Generator Vibrations.Cause Undetermined.Licensee Will Remove & Inspect Generator Rotor

PNO-III-92-045:on 920908,unit Shut Down Due to High Generator Vibrations.Cause Undetermined.Licensee Will Remove & Inspect Generator Rotor

ML20127D957
Person / Time
Site:	Cook
Issue date:	09/09/1992
From:	Jorgensen B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
References
PNO-III-92-045, PNO-III-92-45, NUDOCS 9209150233
Download: ML20127D957 (1)

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Date: September 9, 1992 bc6 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PN39245 This preliminary notification constitutes EARLY notice of events '

of POSSIBLE safety or public interest significance The information is as initially received without verif' .ation or evaluation, and is basically all that is known by the Region III staff on this date.

Facility: Indiana Michigan Licenseem Emeroency Classificatio_n Power Company General Emergency Columbus, Ohio Site Area Emergency .

Alert D. C. Cook, Unit 2 Unusual Event h/g Docket No. 50-316 X _N/A Subjects UNIT SilOTDOWN DUE TO IIIGli GENERATOR VIBRATIONS On September 8, 1992, at 4:13 p.m., the licensee commenced a power reduction of Unit 2 from 87 percent power after vibration levels on the #6 generator bearing increased from approximately 6 to 11 mils. The high vibrational levels persisted during the power reduction; therefore, the unit was removed from the grid and the turbine was manually tripped at about 9:00 p.m. from 8 percent

-power. The unit had previously been paralleled to the grid on September 2, 1992, following an extended period troubleshooting the high vibration on the main turbine and generator bearings.

The reactor is currently being held at 8 percent power and the licensoc is evaluating the root cause of the vibrational problems. ,

The licensee's current focus is on generator eccentricity and shaft runout evaluations. Although the root cause remains to be determined, the licenseo has decided to remove and inspect the generator rotor. An outage of approximately three to four weeks is expected.

The State of Michigan will be notified. The information in this Preliminary Notification has been reviewed with licensee management.

Region III was n9tified of this event at about 4:00 p.m.,

September _8,-199S, This information is current as of 11:30 a.m.

(CDT), Se ber 9, 1992.

CONTACT:/,B.Jorgensen fjg915{g33920909 708/388-5689 PNO-Ill PDR Jigg p DISTRIBUTION:

HEADOUARTERS OFFICES REGIONS _ MAIL TO: !O NMSS Region I DCS (Orig)

'Comm. Rogers OSP Region II DOT (Trans Comm. Curtiss OPA Region IV Only)

Comm. Remick Comm. de Planque OCA 14002'0 "Si "V EDO Gen. Counsel OCAA' FAX TO:

NRR Research The Chairman /EW INPO /2 62 AEOD IRM NSAC /.2/ .5 7 LIC />d5 NRC OPS CTR /JU59 Enforcement ACRS PDR (8/634-3343) /.R ? 5V OIG /JF 4#

-OIG' ilQ Public Af f airs /2 J47 LSSA A. Byrdsong, NRR /2.'4' Region V

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