United States Nuclear Regulatory Commission - Protecting People and the Environment

ACCESSION #: 9705210401


Westinghouse        Energy Systems      Nuclear Services Division

Electric Corporation

                                        Box 355

                                        Pittsburgh, Pennsylvania 15230-


                                        May 14, 1997

U.S.  Nuclear Regulatory Commission

ATTN: Document Control Desk

Washington, DC 20555-0001

Attention: NRC Operations Center

Subject:  Notification of the Potential Existence of Defects Pursuant to


Westinghouse has identified defects that could create a substantial

safety hazard should the defect remain uncorrected.


Deviations were identified by Westinghouse during a lessons learned

review of a pilot program to provide safety-related circuit breaker

refurbishment for the Byron/Braidwood Nuclear Station sites.  The

refurbishment pilot program included both Westinghouse Type DHP Series

and DS Series breakers.  The pilot program was conducted at Westinghouse

satellite facilities and failed to utilize correct procedures which

resulted in certain tests and inspections not being performed or

documented.  The items which were omitted or not documented included the

performance of timing tests, contact resistance checks to correct values,

reapplication of lubricant, opening force margin verification, and weld

inspections.  These tests and inspections are designed to provide

assurance that breaker operation, either to open or close, will be

successfully completed.  W determined that the tests that were performed

on the refurbished breakers before their return to Byron/Braidwood were

insufficient to reestablish full qualification of the breakers.

Safety Significance

The DHP and DS circuit breakers are used in applications such as SI

pumps, RHR pumps, fan coolers and vent fans.  Although unlikely,

installation of breakers that are not fully qualified in redundant trains

could result in the inability to perform a safety function on demand.

Since the Westinghouse data from the pilot program was considered

insufficient, the utility was contacted to collect the operational

history of each breaker after refurbishment to provide reasonable

assurance of operability.  Based on the utility provided data and the

fact that the breakers were refurbished at Westinghouse's facilities

under controlled conditions by competent personnel, it was determined

that the breakers would be operable in the short term.  Additional

cycling was performed on some refurbished breakers to provide confidence

that the breakers would remain operable until proper refurbishment could

he completed.

"The mission of NSD is to provide our customers with people,

equipment and services that set the standards of excellence in the

nuclear industry"


NSD-NRC-97-5093                    2                         May 14, 1997

The only plants involved in the pilot program were Byron and Braidwood

Nuclear Stations.  The population of affected applications is limited to

twelve DHP and twelve DS breakers which were returned to the Braidwood

site and two DS breakers which were returned to the Byron site.

Recommendations/Corrective Action

All of the breakers that were refurbished using incorrect procedures have

been identified.  Personnel from each applicable plant have been notified

and have confirmed operability of the breakers.  As corrective actions,

approved Procedures at Westinghouse's satellite facilities have been

developed for the continued refurbishment of both DHP and DS breakers to

preclude the reoccurrence of this situation.  Plans to complete the

proper refurbishment of all of the returned breakers are being


If you have any questions regarding the notifications, please call me at

(412) 374-5282.

Very truly yours,

H. A. Sepp, Manager

Regulatory and Licensing Engineering




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