ML20107B693

Final Deficiency Rept (53564-K161) Re Uncertainties in Resistance Temp Detectors Calibr.Westinghouse Evaluation Demonstrated That Revised Resistance Temp Detectors Uncertainty Acceptable

ML20107B693
Person / Time
Site:	Wolf Creek
Issue date:	02/07/1985
From:	Koester G KANSAS GAS & ELECTRIC CO.
To:	Denise R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
(53564-K161), KMLNRC-85-050, KMLNRC-85-50, NUDOCS 8502200519
Download: ML20107B693 (5)

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KANSAS GAS AND ELECTRIC COMPANY THE ELECTFhO COMPANY GLENN L MOESTER W48 Pet teOENT - kWCLE A4 February 7, 1985 R.P. Denise, Director Hblf Creek Task Force Reactor Projects Branch 2 U.S. niclear Regulatory Comission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011 KML?aC 85-050 Re: Docket No. STN 50-482 Subj: Final 10CFR50.55(e) Report - RdF RrD Calibration Uncertainties (53564-K161)

Dear Mr. Denise:

The Attachment to this letter provides the final report submitted pirsuant to 10CFR50.55(e) concerning the subject resistance tenperature detectors.

If you have any questions concerning this matter, please contact me or Mr. Gene Rathbun of my staff.

Very Truly Yours, fit $

Glenn L. Koester Vice President - Nuclear l

Attach )

Enclosure  !

l cc: FCDeYoung PO'Connor (2) l HBundy NGuldemcmd l

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1l 201 N. Market - WicNis, Kansas - Mad Address: RO. Box 208 i Wichts, Kansas 67201 - Telephone: Area Code (316) 261-6451

Attachment to KMUSC 85-050 10CPR50.55(e) Report on '

RdP RID Calibration thoertainties (53564-K161)

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Kansas Gas and Electric Conpany

, Wblf Creek Generating Station BL1rlington, Kansas February 7, 1985 i

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I

y. 1 10CF:50.55(e) . Report on 3- adr IUD Calibration theertainties 4

1.0 IMrIGUCTIQi Wis i report . provides a == mary of the deficiency discovered concerning calibration uncertainties- of ItP resistance temperature detectors ~ (RTDs) used to maamire primary system temperature at elf Creek. This deficiency.was reported to the

. IRC in accordance..with the requirements of 10CFR50.55(e). The initial report was made by Messrs Maynard and Chernoff of KGEE to Mr. ' Lawrence Martin of PRC Region IV on January 30, 1985. This concern - was' a ~- new deficiency associated with the same IUD -

uncertainties as an earlier .10CFR50.55(e) . report (References 1

! and 2).

2.0 DESCRIPTION

& TIE PROBUM

, As noted in Reference 1, a Startup Field Report (SPR$1-BB-150)

was generated to document an inconsistency .between calculated -

3 resistance versus tenperature data and measured resistance versus tenperature data which were both supplied by adr. . elf Creek's i

IUDS were returned to the vendor for refurbishment or replacement because of construction damage. Due to the extent of the damage, replacement RIDS were provided to 21f Creek. The replacement IUDS were calibrated by RdF utilizing a revised calibration procedure and shipped to 2 1f Creek.

I j %ere are sixteen narrow range and eight wide range IUDS utilized i in a 4-loop matinghouse plant. Two narrow range IUDS are j installed in each hot leg and cold leg bypass loop. One of these is in service and the other is an installed spare. This report documents .the narrow range and wide range IUD effects.

l m atinghouse has reviewed the calibration data for the e lf Creek i replacement IUDS and has determined that a revised calibration i

i uncertainty is now appropriate. This calibration uncertainty is used by Westinghouse in their setpoint methodology to determine Reactor Trip System instrumentation trip setpoints. However, the l

! IUDS were shiged to 21f Crefek and the SPR dispositioned l allowing their use prior to the completion of Westinghouse's l evaluation.

3.0_ SAFhTY_ IMPACT 3.1 Narrow Range RIDS In their evaluations Westinghouse reviewed the Wolf Creek safety analyses and reactor trip setpoint calculations. It was determined that the following Technical specifications were inpacted by the change in RID calibration uncertainty:

1. Table 2.2-1

a. Item 7, Overtenperature Delta-T setpoint

b. Item 8, Overpower Delta-T setpoint

c. Item 12, Reactor Coolant Flow - low setpoint

2. Specification 3.2.3 and Figure 3.2-3, Flow measurement uncertainty.

Material provided by Reference 3 documented the Technical Specification changes associated with the hardware changeout and is also provided herewith in Enclosure 1 for coupleteness.

Westinghouse in reevaluating affected safety analyses determined that a revised low reactor coolant flow trip point could be acce==vvbted without significantly changing any resultant accident analyses described in the FSAR. A revised FSAR page is provided herewith in Enclosure 2 which shows the trip point change. This change will be included in the first annual FSAR update.

Had the effects of the greater tenperature uncertainty gone unrecognized, Technical Specification required setpoints would have been inproperly set.

3.2 Wide Range RIDS In their evaluation, Westinghouse reviewed the functions which use the wide range RFDs and which could inpact plant safety. The post-accident monitoring, cold-overpressure mitigation, and inadequate core cooling monitoring fanctions were evaluated. It was determined that the increased sensor calibration uncertainties for the RdF RPDs installed at Wolf Creek have no significant inpact on the safe operation of the plant.

4.0 CALEE OF THE DEFICIENCY This deficiency resulted because the RID manufacturer supplied hardware to Wolf Creek which did not meet the Westinghouse specification.

5.0 uJeuaa;nVE ACTION The safety analysis inpacts were evaluated by Westinghouse.

With the Technical Specification changes given in Enclosure 1 and the FSAR change given in Enclosure 2 prcper reactor protective actions are ensured and FSAR accident analyses envelope design bases conditions. Thus, the evaluation described herein has demonstrated that the revised luD uncertainty is acceptable.

KG&E procedures will be revised to reflect the new setpoint values. The associated instrumentation will be recalibrated to the new setpoints prior to Wb1f Creek's initial criticality.

6.0 ler uBNCES

1. KMLNRC 84-158 dated 8/31/84 from GKoester, KGEE to EHJohnson, NRC

2. KMLNRC 84-216 dated 12/7/84 from GKoester, KGGE to RPDenise, NRC

, 3. SINRC 85-5 dated 2/1/85 from NAPetrick, SNUPPS to HRDenton, NRC d

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