ML20086J363

Telecopy AO 74-13:on 741015,HPCI Gland Seal Condenser Head Gasket Found Leaking.Caused by High Spots in Area Between Internal Baffles & Tube Sheet.Plant Shut Down.High Spots Removed.New Head Gasket Installed & Head Tightened

ML20086J363
Person / Time
Site:	Peach Bottom
Issue date:	10/16/1974
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086J362	List: ML20086J358 ML20086J363
References
AO-74-13, NUDOCS 8401230607
Download: ML20086J363 (2)

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PHIIADFLPilIA ELECTRIC COMPAhY gg.w.asuunw f Peach Ecttom Atomic Power Station Delta, Pennsylvania ---

17314 October 16, 1974 Mr. James P. O'Reilly, Director United States Atomic Energy Cornission Directorate of Regulatory Operations 631 Park Avenue Eing of Prussia, Pennsylvania 19406 Subj ec t : Abnormal Occurrence 24-Hour Notification Confirning W. T. Ullrich's phone conversation with Mr. Walt Baunack, A.E.C.

Region 1 Regulatory Operations Of fice on October 15, 1974.

Reference:

License Number DPR-56 Technical Specification Reference 3.5.C.1 Report No.- 50-278-74-13 Report Date: October 16, 1974 Occurrence Date: October 15, 1974 Facility: Peach Botton Atomic Power Station R.D. 1, Delta, Pennsylvania  ;

Identification of Occurrence-HPCI El and seal condenser head gasket leak.

Conditions Prior to Occurrence:

Reactor at approxinately 35% power. Electrical power output 327 MW.

Description of Occurrence:

During a HPCI injection to the reactor vessel perforced as part of the startup test program, a Icak was noted on the HPCI gland seal condenser head gasket. The vessel injection test was successful.

However, to reduce leakaRe of water from the condennate tank to the HPCI room, the HPCI pump had to be isolated, thereby making the HPCI system inoperable.

Designation of Apparent Cause of Occurrence:

The head gasket leak is believed to have been caused by high spots in the area between the internal baffles and the tube sheet. These high spots prevented proper cocpression of the head gasket.

Analynis of Occurrence:

Since the unit was only at 35% power and had only operated at a maximum 60% power for a short ti=e, decay heat load was significantly below the equilibrium full power value. With both the HPCI ano one RHR pump inoperable, sufficient emergency cooling systens were available. This occurrence has minimal safety significance.

8401230607 741025 3 PDR ADOCK 05000278 a '

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.2-Corrective Action:

With the HPCI inoperable and one PJiR pump out of service, the '

Technical Specifications require a plant shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.  ;

The plant was therefore shutdown to a cold shutdown within the  ;

allowable time interval.

The high spots noted following dise.antling of the heat exchanger [i head were removed to produce an interference-free sealing surface.

A new head yngEtt van inatalled nna the head _pInper.ly-1.ightenst ,

Operational testing of the HPCI is scheduled during the next startup period.

I Failure Data:

During the Unit 2 startup program, ninor Icakage on the same gland l seal condenser head gasket was noted and corrected on several occasions. Investigation of these problems also identified the ~

l interference probicm between the internal baf fle and the tube chect.

Correction of this probics on Unit 2 has apparently resolved the Icakage. '

1 ll235552iUfMd2.2mdbt.fics.TswwUEdu7missa.!.mvs.wza%Khnen 'dM~d%=7 l Very truly yours, N 2<'ch&

W. T. Ullrich, Superintendent Peach Bottom Atomic Power Station 1

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