ML20091M346

Final Significant Const Deficiency Rept 99 Re Safety Injection Tank (SIT) Isolation Valves Supplied by Lunkenheimer Corp.Initially Reported on 840525.Failed Components for Actuators on Three Valves Replaced

ML20091M346
Person / Time
Site:	Waterford
Issue date:	05/29/1984
From:	Gerrets T LOUISIANA POWER & LIGHT CO.
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
99, W3K84-1281, NUDOCS 8406110247
Download: ML20091M346 (3)

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LOUISIANA 242 octanoNoe srnter POWER & L1GHT P O box 6008

• NEW OnLEANS. LOUISIANA 70174 * (504) 366-2345 UTIUTIES SYSTEM May 29, 1964 W3K84-1281 Q-3-A35.07.99 i-2@20W2 %

Mr. John T. Collins Regional Administrator, Region IV

~ dM U. S. Nuclear Regulatory Commission y

j 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012 REF1'RENCE: LP&L letter W3K84-1062 dated May 4, 1984 Telecon C. Hooper (LP&L) and Eric Johnson (NRC IV) on May 25, 1984

SUBJECT:

Waterford SES Unit No. 3 Docket No. 50-382 Significant Construction Deficiency No. 99

" Safety Injection Tanks (SIT) Isolation Valves" Final Report In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Final Report of Significant Construction Deficiencies No.

99, " Safety Injection Tanks (SIT) Isolation Valves".

If you have any questions, please advise.

Very truly yours, M d 4+u"5 T. F. Gerrets Corporate Quality Assurance Manager TFG:CNH:VBR Attachment cc: Director Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C.

20555 (15 copies)

J.&F7 8406110247 840529 PDR ADOCK 05000382

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~ 6 Mr. John T. Collins l

May'29, 1984 W3K84-1281

-Page'2 l

cc:. Director Office of Management Information and Program Control U. S. Nuclear Regulatory Commission Washington, D.C.

20555 Mr. E. L. Blake Shaw, Pittman, Potts & Trowbridge 1800 M Street, N.W.

Washington, D.C.

20036 Mr. W. M. Stevenson Monroe & Lemann 1424 Whitney Building New Orleans, Louisiana 70130 Records Center Institute of Nuclear Power Operations 1100 circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 Mr. W. A. Cross 7910 Woodmont Avenue

-Suite 1200 Bethesda, Maryland - 20814 1

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FINAL REPORT OF SIGNIFICANT CONSTRUCTION DEFICIENCY No. 99

" SAFETY INJECTION TANKS (SIT) ISOLATION VALVES" INTRODUCTION This report was previously submitred pursuant to 10CFR50.55(e) and was Econsidered reportable.

It described a deficiency in the performance requirements of Safety Injection Tanks (SIT) Isolation Valve ISI-V1507 TK2A

.(SI-332A) supplied by the Lunkenheimer Corporation with a Limitorque Corporation. Actuator.

To.the best of our knowledge, this problem has not been reported to the USNRC pursuantLeo 10CFR21.

DESCRIPTIONS During Preoperational Testing, SIT Isolation Valve ISI-V1507 TK2A (SI-332A) appeared to mechanically bind, causing the valve motor to trip on overload.

Inspection of the valve actuator found a broken motor pinion gear, stripped worm gear and' broken retainer ring.

In addition LP&L's investigation has revealed that two similar incidents have previously occurred involving SIT Isolation Valves ISI-V-1505-TKIA and ISI-V15060TKlB.

SAFETY UMPLICATIONS The valves in question are locked open when RCS pressure is increased.above 500 psig during normal power operation. During plant cooldown and shutdown cooling, the SIT pressure is reduced to 377 psig when RCS pressure decreases-below 650 psig. l&en RCS pressure is below 400 psig, the SIT isolation valves will<be: closed. FSAR Section 6.3.2.2.1 requires that these valves open on demand frca an SIAS when the RCS pressure is less than 400 psig. This function ensures that the tanks.will discharge automatically'during a LOCA.

'Therefore,'if.left uncorrected, the failure of these' valves would result in the-inability to automatically discharge-into the RCS following a depressurization event.--

CORR?ETIVE ACTION TAKEN All failed components for the actuators of the three' valves have been replaced-and tested satisfactorily. Since the failed parts were scrapped no material' analysis was accomplished. However,-the motor pinion'from the fourth SIT.

Isolation. valve actuator.was removed and tested.by Limitorque Corporation.

Limitorque has" certified the material to be free of defect and the motor

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pinion gear sizing to be correct. All SIT' Isolation valve torque switch-settings have been verified to be set in accordance with manufacturer-specifications;. Valve ISI-V1507 TK2A'(SI-332A) was successfully stroke tested

'(132 cycles)-from the control room. 'After cycle testing the motor pinion sear was inspected and.found to be acceptable.

This report'is' submitted as the Final Report.

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