TXX-8852, Supplemental Deficiency Rept CP-85-49 Re Unevaluated Fluid Transient in Steam Supply Line for Turbine Driven Auxiliary Feedwater Pump (Tdafp).Initially Reported on 851220.TDAFP Will Be Tested W/Revised Piping Configuration

Supplemental Deficiency Rept CP-85-49 Re Unevaluated Fluid Transient in Steam Supply Line for Turbine Driven Auxiliary Feedwater Pump (Tdafp).Initially Reported on 851220.TDAFP Will Be Tested W/Revised Piping Configuration

ML20196J624
Person / Time
Site:	Comanche Peak
Issue date:	06/29/1988
From:	Beck J TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
CP-85-49, TXX-88520, NUDOCS 8807060419
Download: ML20196J624 (2)

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F "" log # TXX-88520 "1 O File # 10110 Z C 906.2 7UELECTRIC Ref. # 10CFR50.55(e) y/I,"1$,$,,, June 29, 1988 U. S. Nuclear Regulatory Commission e Attn: Document Control Desk Washington, D.C. 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET NOS. 50-445 AND 50-446 MAIN STEAM LINE FLUID TRANSIENT SDAR: .CP.-85-49 (SUPPLEMENTAL REPORT)

Gentlemen:

On December 20, 1985, we informed you by our final report logged TXX-4656 of a reportable deficiency involving an unevaluated fluid transient in the steam supply line for the turbine driven auxiliary feedriater pump (TDAFP). Our letter logged TXX-6435, dated May 13, 1987, identified this issue as one for which the corrective actions and schedule for implementation required revision. This supplemental report provides the revised corrective actions and completion schedule.

In TXX-4656, we stated that in' order to remove moisture accumulation more effectively, the piping system would be redesigned to increase the slope and provide additional condensate drain pots. Further engineering evaluation has determined that increasing the slope of the affected lines is adequate to ensure proper drainage. Therefore, additional drain pots will not be installed. The TDAFP will be tested with the revised piping configuration to ensure that any condensation which occurs on a cold start and is not removed by the existing drain pots, can not prevent the system from performing its safety function.

A warm up by-pass line around each steam supply isolation / control valve has also been included in the redesign to minimize cold starts of the TDAFP.

This by-pass line is normally locked closed and will be used only in i surveillance testing of the TDAFP operability. Additionally, the opening time of the steam supply isolation / control valves will be sluwed to reduce the loads imposed on the piping system.

8807060419 880629 PDR i S ADOCK 05000445 ppe A lfp 400 North Olive Street LBof E41!as. Tem 73201 J

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,,Jo TXX-88520 June 29, 1988 Page 2 of 2 The above modifications will be completed by August 31, 1988, for Unit 1, with testing to take place during Unit 1 Hot Functional Testing. The Unit 2 modifications will be completed prior to Unit 2 Hot Functional Testing.

Very truly yours, W. G. Counsil By: V. b Johti W. Beck Vice President, Nuclear Engineering CBC/grr c-Mr. R. D. Martin, Region IV Resident Inspectors, CPSES (3)

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