ML17238A725

Unit #3 Sections 6.6.A.1 and 6.6.B.2 of Technical Specifications - Regarding the Failure of the HPCI Turban to Reset

ML17238A725
Person / Time
Site:	Dresden
Issue date:	05/25/1972
From:	Worden W Commonwealth Edison Co
To:	Bloch E US Atomic Energy Commission (AEC)
References
Download: ML17238A725 (2)

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Commonwealth Edison Company ONE FIRST NATIONAL PLAZA* CHICAGO. ILLINOIS Address Reply fo; POST OFFICE BOX 767 *CHICAGO, ILLINOIS 60690 Dresden Nuclear Power Station R. R. /fl Morris, Illinois 60450 May ,25, 1972 Mr. E. J. Bloch, Director Division of Reactor Licensing U.S *. Atomic Energy Conunission Washington, D. C. 20545 50-249

SUBJECT:

I::.ICENSE DPR-25, DRESDEN NUCLEAR POWER STATION UNIT 113 SECTIONS 6.6.A.l AND 6.6.B.2 OF TECHNICAL SPECIFICATIONS.

Dear Mr. E. J. Bloch:

This is to report a condition relating to the operation of the st~tion in which during monthly surveillance, the High Pressure Coolant Injection (HPCI) turbine would not reset. Failure of the turbine to rese_t .re11dered the sysJem ..i~capable of prov;iding coolant inject.ion ;:is.

'r~qui~ed "by Section 3*;5." c. f of the Dre~den Unit 113 Technical Specifica-tions.

PROBLEM AND INVESTIGATION HPCI monthly surveillance was being conducted on May 19, 1972, and it was found that the turbine would not reset from the Control Room.

The turbine was reset locally.* 'and the turbine surveillance test was satisfactorily completed. On.,Saturday, May 20, 1972, an electrician found a wire broken off the turbine reset solenoid. This wire was recon-nected and a new solenoid was ordered. The new solenoid will be installed when received.. This surveillance test was last conducted on April 20, 1972, and the turbine reset satisfactorily at this time. In addition, during the plant trip of May 4, 1972, the HPCI turbine was called upon to operate and the turbine reset satisfactorily.

CONCLUSION AND CORRECTIVE ACTION The cause of the failure appears to be a brittle failure of a terminal on the solenoid. New solenoids have been ordered to replace this solenoid and the similar one on the D-2 HPCI turbine. . ll' F*/

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• Mr. E. J. Bloch May 25, 1972 Further investigation of the failure mechanism will be conducted by the Commonwealth Edison Engineering Department and further action will be taken if required.

Sincerely, W. P. Worden Superintendent WPW:do

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