ML20073R088

RO 83-11:on 830326,DHR 1A Shaft Bearings Failed,Making Pump Inoperable.Caused by Design Change to Pump Bearing Lube Oil Sys.Sys Returned to Original Configuration.Review of Existing Sys in Progress

ML20073R088
Person / Time
Site:	Three Mile Island
Issue date:	04/18/1983
From:	Hukill H GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
5211-83-120, RO-83-11, NUDOCS 8305030436
Download: ML20073R088 (2)

Text

. o GPU Nuclear Corporation G U tuclear = = neeSs48o Middletown, Pennsylvania 17057 717 944-7621 TELEX 84 2386 Writer"s Direct Dial Number:

April 18, 1983 5211-83-120 Regional Administrator Region I U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Dear Sir:

Three Mile Island Nuclear Station, Unit 1 (TMI-1)

Operating License No. DPR-50 Docket No. 50-289 LER 83-11 This letter confirms the conversations on March 28, 1983 (R. J. Toole to R. Conte), April 11,1983 (M. A. Nelson to A. Fasano and F. Young) and on April 15, 1983 (M. A. Nelson to A. Fasano, final declaration of reportability) concerning reportability of following event.

At 3 p.m. on April 15, 1983, it was determined that an incident involving the Decay Heat Removal Pumps was reportable per Tech Spec 6.9.2.A.9. The incident occurred on March 26, 1983 and has been under investigation since.

On March 26, 1983, the Decay Heat Pump 1A shaft bearings failed, making the pump immediately inoperable. The investigation determined that a new design change that was made to the pump bearing lube oil system did not work correctly. Because of an inadequate understanding of the new oiling design, the operators removed the manual oiler from the pump and because of inadequate calibration of the new oiler, the bearing lost lubrication.

Action was required to return the lubrication system for both DH-PlA & 1B to their original configuration. This failure is, therefore, reportable under Tech. Spec. 6.9.2. A.9, " Performance of structures, systems, or com-ponents that require remedial action...".

In addition to returning the system to their original configuration, a review of the existing oiler design is underway.

8305030436 830418 PDR ADOCK 05000289 s PM GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation g

p w

l Regional Administrator 5211-83-120  ;

The details of this occurrence and correcti- 'ction to prevent recurrence will be provided in a follow-up report.

Sincerely,

$1 b Director, TMI-1 IIDil:CWS:vj f cc: J. Van Vliet R. Conte

.