Ev ,ios Marinos - UFM Bulletin status . . . ... . . . . .. . . Page 1-

From:To:Date:Subject:

Evangelos MarinosChristopher Grimes; Jared Wermiel; Jose CalvoWed, Jul 21,2004 4:31 PMUFM Bulletin status

Chris,I have scheduled a one hour briefing to Ellis Merschoff on July 29 at 10:30, in his office, Room 017H20and I have included Brian Sheron and Richard Barrett on the list of attendees in case they want to attend.

Attached are the proposed CRGR briefing slides we went through this morning at our strategy meeting.

CC:Barrett

Brian Sheron; Ellis Merschoff; George Dick; Gregory Cwalina; lqbal Ahmed; Richard

lq-,39

NRR PRESENTATION TO CRGRULTRASONIC FLOW METER (UFM) FORMEASURING FEEDWATER FLOW USED

IN DETERMINING REACTOR THERMAL POWER

C4

August 5, 2004

Evangelos C. Marinos, Section Chief

Instrumentation and Controls

Electrical & Instrumentation & Controls Branch

Division of Engineering, NRR

U. S. Nuclear Regulatory Commission

CPRESENTATION TOPICS

1) Reactor Thermal Power Measurement Page 3 - 7

2) Appendix K to Part 50- ECCS Evaluation Models Page 8

3) Ultrasonic Flow Meter Technologies Page 9 - 11

4) Non Power Uprate use of Ultrasonic Flowmeters Page 12

in Nuclear Power Plants

5) Staff Review of Vendor Topicals Page 13 - 14

6) Staff Licensing Reviews Page 15

7) Allegations Regarding Crossflow UFM Accuracy Page 16- 18

8) Staff Concerns of UFM Accuracy Page 19 - 20

Slide 2 of 20

REACTOR THERMAL POWER MEASUREMENT

PWR Calorimetric Calculation Principle Parameters" Feedwater Flow" SG Blowdown Flow• SG Blowdown Liquid Enthalpy" Feedwater Density

- Temperature- Pressure

* Feedwater Enthalpy

- Temperature- Pressure

* Steam Enthalpy

- Temperature- Pressure

" Net Pump Heat Addition

Slide 3 of 20

REACTOR THERMAL POWER MEASUREMENT(Continued)

BWR Heat Balance Calculation Principle Parameters

* Feedwater Flow

• Feedwater Temperature

° Main Steam Pressure

* Reactor Water Cleanup Flow

" Reactor Water Cleanup Temperature

* Control Rod Drive Temperature

Slide 4 of 20

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REACTOR THERMAL POWER MEASUREMENT(Continued)

Typical Feedwater Flow Uncertainty Calculation

Watts Bar Unit 1, April 2003

InstrumentError

0.5K

FlowUncertainty

0.5%(Per ASME PCT 19.1 1998)

+a,c

Venturi

Thermal Expansion Coef.

Temperature

Material

Density

Temperature

Pressure

AP

1.40 F

5.0%

0.0

0.06

0.06

0.01

0.4

1.40 F

35.5 psi

0.5% AP

Total Loop Uncertainty (TLU)

TLU= j(.5)2 +(.06)2 +(.06)2 +(.06)2 +(.01)2 +(.4)2 =.64%

Slide 5 of 20

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00 REACTOR THERMAL POWER MEASUREMENT

(Continued)Vetr MesrdFewtrFo tFl oeVenturi Measured Feedwater Flow at Full Power

-- Diablo Canyon, 1995

Venturi - Based Flow Readings

+a,c

0

U)

E

Sa-

14900

14880

14860

14840

14820-I . .

14800 -

14780 t

14760 .

14740

14720

14700

0 2 4 6 8

Actual Value: 14850

Mean Reading: 14806.7* * 0 ---- - . .

10 12 14

trial #16 18 20 22 24 26

Venturi Uncertainty demonstrated at Alden Labs: 0.251 %

Readings recorded over 3-hour period

Instrument loop precision from regression analysis: 0.07%

Instrument loop accuracy: .3%

TLU = (.07) + (.3)2 =.31%

Slide 6 of 20

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REACTOR THERMAL POWER MEASUREMENT(Continued)

IVenturi Measured Feedwater Flow at Full Power

-- Kewaunee, 2002

Venturi - Based Flow Readings(test starting 11124102,19:39:00)

+a,c

0

I-

7185

7180

7175

7170 '

Actual Value: 7180

R..

7165 .

7160

7155

7150

0 500

Mean Reading: 7165.9

1000 1500 2000

Trial #2500 3000 3500 4000

Readings recorded over 12-hour period

Instrument loop precision from regression analysis: .095%

Instrument loop accuracy: .2%

TLU = (.095)2 + (.2y) =.22%

Slide 7 of 20

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APPENDIX K TO PART 50- ECCSEVALUATION MODELS

Source of heat during the LOCA

" Reactor assumed operating continuously at a power level at least 1.02 times the licensed

power level (to allow for instrumentation error)

" An assumed power level lower than 1.02 times the licensed power level may be usedprovided the proposed alternative value has been demonstrated to account foruncertainties due to power level instrumentation error.

Slide 8 of 20

ULTRASONIC FLOW METER TECHNOLOGIES

Transit Time Technology - Leading Edge Flow Meter (LEFM) (Caldon)

Clamp-On Type Instrument

J1u

soi ae

Angle of the Sonic Wave to Flow = a

v = L(Ti - T) (2T1T2cos a)

AT •- 1uSecondFluid velocity (V) is determined by the difference in time of two sonic waves traveling inopposite directions.

Slide 9 of 20

ULTRASONIC FLOW METER TECHNOLOGIES(Continued)

o In-Line Type LEFM Instrument

LEFM Check 4- LEFM Check = LEFM CheckPlus

LEFM Check . + LEFM Check

LEFM CheckPlus

Operates on same principle as Clamp-On Type

Slide 10 of 20

ULTRASONIC FLOW METER TECHNOLOGIES(Continued)

* .*4

Cross Correlation Technology - Westinghouse / Advanced Measurement and Analysis

Group (W/AMAG)

Clamp-On Type (Crossflow) Instrument

A

v-L

r-50ms

Fluid Velocity (V) is determined by the time difference of two modulated signals shifted inphase by unique pattern of eddies in the fluid.

Slide 11 of 20

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41

NON POWER UPRATE USE OF ULTRASONICFLOWMETERS IN NUCLEAR POWER PLANTS

One-time venturi calibration.

Power Recovery from fouled venturies.

Use of Transit Time Clamp-On-Type, LEFM instrument, resulted in over 2% overpower atRiver Bend and approximately 1% - 3% at Palo Verde 1 & 2, caused by the instrument notmeeting its expected accuracy.

Use of Cross Correlation Clamp-On-Type Crossflow instrument resulted in over 2%overpower at Byron 1 and approximately .8% - 1% at Byron 2 and Braidwood 1&2 causedby an apparent misapplication of the instrument.

Slide 12 of 20

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00

tSTAFF REVIEW OF VENDOR TOPICALS

Caldon In-line Type LEFM Instrument

* Topical Report ER-80P, "Improving Thermal Power Accuracy and Plant Safety WhileIncreasing Operating Power Level Using The LEFM/ TM System," Revision 0, dated March1997, submitted for staff review

- Staff issued Safety Evaluation Report (SER) dated March 8, 1999, acceptingdocumented accuracy of instrument.

" Topical Report ER-157P, "Supplement to Topical Report ER-80P: Basis for a PowerUprate with the LEFM/ TM or LEFM Check Plus TM System" Revision 3, dated February2001, submitted for staff review

- Staff issued SER dated December 20, 2001 accepting documented enhancedaccuracy of instrument.

Slide 13 of 20

STAFF REVIEW OF VENDOR TOPICALS(Continued)

Westinghouse I AMAG Clamp-On Type Crossflow Instrument

Topical Report CENPD-397-P-A, "Improved Flow Measurement Accuracy UsingCrossflow Ultrasonic Flow Measurement Technology" Revision 0, dated August 1999submitted for staff review

- Staff issued SER dated March 20, 2000 accepting documented accuracy ofinstrument.

Slide 14 of 20

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0 STAFF LICENSING REVIEWS

Plant Applications for Measurement Uncertainty Recapture (MUR) Power Uprates (1.4-1.7%)

o Regulatory Information Summary RIS 2002-03, "Guidance on the Content ofMeasurement Uncertainty Recapture Power Uprate Application" dated January 3, 2002issued to licensees to provide consistent guidance for application submittals.

* Uprates granted by the staff to plants using Caldon LEFM In-Line Instrument forFeedwater measurement:

- 21 power plants

Beaver Valley 1Comanche Peak 1Comanche Peak 2Indian Point 2

Indian Point 3Point Beach 1Point Beach 2

Sequoyah 1

Sequoyah 2Susquehana 1Susquehana 2Watts Bar

Beaver Valley 2D. C. Cook 1D. C. Cook 2

Grand Gulf

Peach Bottom 2

Peach Bottom 3

River Bend

H. B. Robinson

Waterford 3

Uprates granted by the staff to plants using Westinghouse / AMAG Crossflow Clamp-OnInstrument for Feedwater measurement:

12 power plantsPilgrim Hope Creek San Onofre 2 Hatch 1 South Texas 1Kewaunee Salem Unit I San Onofre 3 Hatch 2 South Texas 2Fort Calhoun Salem Unit 2

Slide 15 of 20

0QaRE~, ALLEGATIONS REGARDING CROSSFLOW UFMACCURACY

February 15, 2000: Letter from Caldon expressing concern that the cross correlationinstrument under review by the staff can not support significant reduction in the 2%power uprate margin of Appendix K.

March 8, 2000: NRC met with Caldon in a public meeting to address Caldon's concerns withpending staff SER approving use of WIAMAG CrossFlow instrument.

March 15, 2000: Letter from Caldon reaffirming their conclusion that the CrossFlowinstrument could not achieve a bounding value of 0.5%.

March 17, 2000: Follow-up letter from Caldon stated that uncertainties with CrossFlowinstrument can be as high as 3%.

March 17, 2000: Internal NRC memorandum from Jack Cushing to Stuart Richardssummarizing public meeting with Caldon on March 8, 2000.

Slide 16 of 20

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ALLEGATIONS REGARDING CROSSFLOW UFMACCURACY (Continued)

Caldon Engineering Report ER-262, Revision 0, "Effects of Velocity Profile ChangesMeasured In-Plant on Feedwater Flow Measurement Systems" dated January 2002,submitted to the staff for information.

" Report identified swirl velocity phenomenon, whereby velocity profile correction factorscould be correcting underestimated mass flow rates not previously accounted in theuncertainty calculations for Clamp-on and In-line LEFMs.

" Report categorizes Clamp-on users in Categories A, B, C, & D and issued separatereports exempting those in Categories A, B, & C from the effects of the swirl velocityphenomenon.

" In-line LEFM users account for inaccurate correction factors by a change in boundingalarm.

* Staff informal review confirmed Caldon's determination that accuracy data of the TransitTime Clamp-On LEFM instruments do not invalidate the accuracy of the LEFM In-lineinstruments approved by the staff.

" On February 12, 2002 Caldon requested formal staff review of ER-262 to addressCaldon's concern previously stated that the W / AMAG CrossFlow Clamp-On instrumentdoes not meet the accuracy approved by the staff.

Slide 17 of 20

ALLEGATIONS REGARDING CROSSFLOW UFMACCURACY (Continued)

On September 12, 2002 W/ AMAG submitted unsolicited report WCAP-15689-P, Revision1, "Evaluation of Transit-Time and Cross-Correlation Ultrasonic Flow MeasurementExperience with Nuclear Plant Feedwater Flow Measurement" dated September 2002,addressing concerns raised by Caldon in the ER-262 report.

On January 28, 2003 the staff issued evaluation of ER-262 reaffirming that the accuracy

data of the Caldon Clamp-On Transit Time instrument do not invalidate the accuracy ofthe In-Line LEFMs approved by the staff and the data have no relationship to theW/AMAG Crossflow instrument.

Slide 18 of 20

STAFF CONCERNS OF UFM ACCURACY

NRC independent Task Group formed on February 2, 2004 to address concerns regardingaccuracy of W/AMAG Crossflow instrument. Task Group considered informationavailable through mid-April, 2004. Reports issued June 7, 2004.

Identified issues with (1) one time UFM, (2) power recovery, and (3) power uprate

applications.

* Crossflow sensitive to plant configurations and has not provided intended accuracy insome installations. The reasons have not been fully demonstrated to the staff.

o Crossflow may provide expected accuracy if properly implemented.

" Some Caldon clamp-on UFMs have not provided intended accuracy. Caldon LEFM\1 andLEFM CheckPlus UFMs appear less sensitive to installation configuration than clamp-ondesigns.

" Task Group does not have information based upon recent insights that demonstrates allUFMs are providing intended accuracy.

* Recommended bulletin to obtain information to demonstrate that UFMs are providing theintended accuracy consistent with the plant license.

Slide 19 of 20

STAFF CONCERNS OF UFM ACCURACY

(Continued)

Draft Bulletin 2004-XX being proposed to:

* Advise addressees that plant operating experience at some installations has led the staff toconclude the W/AMAG Crossflow and Caldon LEFM (both Clamp-On-Type) UFM have not providedthe intended Feedwater flow rate accuracy to maintain plant operation within the licensed thermalpower.

0 Advise addressees that there are potential questions regarding application of Caldon LEFM / andLEFM Check Plus UFMs, because of plant configuration sensitivity due to such phenomena as +swirl velocity reported in Engineering Report ER-262 and lack of empirical data that can confirminstrument performance at plant conditions. Presently performance has been based onextrapolated data from lab tests with temperature values on the order of 300 degrees lower thanthose expected at the plant and with Reynolds numbers one-sixth those expected.

" Recommend that licensees may confirm UFM accuracy by comparing the instrument performancein operational plant conditions against measurement values of a fully clean ASME flow nozzle orventuri, of known accuracy, or any other standard test of known accuracy, and

* Require addresses to provide a written response to the NRC in accordance with the provisions ofSection 50.54(f) of Title 10 of the Code of Federal Regulations (10 CFR 50.54(f), to verify thatactions have been taken to ensure that each addressee's plant(s) is (are) not operated above thelicensed thermal power level or outside the licensed design basis.

Slide 20 of 20