ML20029A309

Nonproprietary Sequoyah Nuclear Plant Unit 2 Cycle 5 Restart Physics Test Summary.

ML20029A309
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Site:	Sequoyah
Issue date:	01/31/1991
From:	Strange J TENNESSEE VALLEY AUTHORITY
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PFE-G22NP, PFE-GN22NP, NUDOCS 9102150039
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,

i ENCLOSURE 2 SEQUOYM NUCLEAR PIANI (SQN),

UNII2 CYCLE 5 RESIARTPilYSICSIESISUMRY (PFE-022NP)

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Sequoyah Nuclear Plant Unit.2, Cycle 5  !

Restart Physics Test Summary Nuclear Fuel PWR Fuel Engineering January 1991 l

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Prepared by f f l ,$t f & page 7_ , 7. g, Approved by u

NW Date /- J .? - 9 /

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ABSTRACT The Sequoyah Nuclear Plant Unit 2, Cycle 5 Restart Physics Test Summary cov r3 the period from September 21, 1990 through December 31, 1990. The report presents restart physics test results and operational data for the first 32 effective full-power days (EFPD). The tests included are initial criticality, primary coolant critical boron concentration, reactivity control, isothermal temperature coefficient, and power distribution measurements, i

The results in this report have been verified in accordance with l Nuclear Fuel Instructions.

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1, TABLE OF CONTENTS Section . Title Page

-ABSTRACT. . . . . . . . . . . . . . . . . . . . . 1 LIST OF TABLES. .. . . . . . . . . . . . . . . . . iii LIST OF FIGURES . . . . . . . . . . . . . . . . . iv 4

1. 0 - INTRODUCTION AND CYCLE DESCRIPTION. . . . . . . . 1 2.0 TEST PROGRAM

SUMMARY

. . . . . . . . . . . . . . . 6 3.0 CORE RELOAD

SUMMARY

, . . . . . . . . . . . . .. 12 4.0 CORE PERFORMANCE. . . . . . . . . . . . . . . . . 15 4.1 INITIAL CRITICALITY . . . . . . . . . . . . . . . 15 4 .' 2 CORE-DEPLETION. . . .. . . . . . . . . . . . . . 15 4.3 REACTIVITY CONTROL. . . . . . . . . . . . . . . . 16:

'4.3.1 CONTROL'OD R BANK WORTH MEASUREMENTS . . . 16 4.3.2 BORON WORTH AND ENDPOINT MEASUREMENTS . . 16 4.4 . ISOTHERMAL TEMPERATURE COEFFICIENT MEASUREMENTS . 17 4.5 POWER DISTRIBUTION MEASUREMENTS . . . . . . . . . 17 4.5.1- ASSEMBLY POWER DISTRIBUTIONS. . . . . . . 18 4.5.2 FQ(Z) SURVEILLANCE. . . . . . . . . . . . 18 4.5.3 FDHN SURVEILLANCE . .. . . . . .. . . . . 19 4.5.4 INCORE-EXCORE CALIBRATION.. . . . .- . . . 19 11

a LIST OF TABLES Table Title 1.1 SEQUOYAH UNIT 2, CYCLE 5 CORE DESIGN PARAMETERS . . 2 1.2 SEQUOYAH UNIT 2, CYCLE 5 FUEL SPECIFICATIONS. . . . 3 2.1 SEQUOYAH UNIT 2, CYCLI 5 CHRONOLOGY.OF STARTUP PHYSICS TESTS . . . . . . . . . . . . . . . . . . . 7 2.2 SEQUOYAH UNIT 2, CYCLE 5 SIGNIFICANT EVENTS

SUMMARY

, . . . . . . . . . . . . . . . . . . . . . 8 4.3.1 SEQUOYAH UNIT 2, CYCLE 5 ROD SWAP INTEGRAL BANK WORTHS. . . . . . . . . . . . . . . . . . . . . . . 29 4.5.1 SEQUOYAH UNIT 2, CYCLE 5 INCORE FLUX MAP

SUMMARY

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LIST OF FIGURES Figure Title 1.1 SEQUOYAH UNIT-2, CYCLE 5 CORE COMPONENT CONFIGURATION . . . . . . . . . . . . . . . . . . . 5 2.1 SEQUOYAH UNIT 2, CYCLE 5 MONTHLY REACTOR POWER ,

HISTOGRAM FOR NOVEMBER 1990 . . . . . . . . . . . . 10 2.2 SEQUOYAH UNIT 2, CYCLE 5 MONTHLY REACTOR POWER HISTOGRAM FOR DECEMBER 1990 . . . . . . . . . . . . 11 3.1 SEQUOYAH UNIT 2, CYCLE 4 FINAL BURNUP DISTRIBUTION. 13 3.2 SEQUOYAH UNIT 2, CYCLE 5 INITIAL CORE LOADING PATTERN . . . . . . . . . . . . . . . . . . . . . . 14 4.1.1 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO DURING ROD WITHDRAWAL FOR N-31. . . . . . . . . . . 20 h 4.1.2 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO I DURING ROD WITHDRAWAL FOR N-32. . . . . . . . . . . 21 4.1.3 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO VERSUS TIME DURING DILUTION N-31. . . . . . . . . . 22 4.1.4 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO VERSUS TIME DURING DILUTION N-32. . . . . . . . . . 23 4.1.5 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO VERSUS GALLONS OF DILUTION N-31 . . . . . . . . . . 24 4.1.6 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO VERSUS GALLONS OF. DILUTION N-32 . . . . . . . . . . 25 4.1.7 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO L VERSUS BORON CONCENTRATION N-31 . . . . . .. . . . 26 4.1.8 SEQUOYAH UNIT 2, CYCLE 5 INVERSE COUNT RATE RATIO VERSUS BORON CONCENTRATION N-32 .. . . . . . . . . 27 4.2.1 SEQUOYAH UNIT 2, CYCLE 5 BORON LETDOWN CURVE. . . . 28-4.3.1 SEQUOYAH UNIT 2, CYCLE 5 INTEGRAL BANK D WORTH. . . 30 4.3.2 SEQUOYAH UNIT 2, CYCLE 5 DIFFERENTIAL BANK D WORTH.- 31 4.5.1 SEQUOYAH UNIT 2, CYCLE 5 RELATIVE ASSEMBLY POWERS INC-5-F2-90-1B. . . . . . . . . . . . . . . . . . . 33 iv 1

LIST OF FIGURES (continued) 4.5.2 SEQUOYAH UNIT 2, CYCLE 5 RELATIVE ASSEMBLY POWERS INC-5-F2-90-2A. . . . . . . . . . . . . . . . . . . 35 4.5.3 SEQUOYAH UNIT 2, CYCLE 5 RELATIVE ASSEMBLY POWERS INC-5-F2-90-11A . . . . . . . . . . . . . . . . . . 37 4.5.4 SEQUOYAH UNIT 2, CYCLE 5 NORMALIZED AVERAGE AXIAL POWER DISTRIBUTION INC-5-F2-90-1B . . . . . . . . . 39 4.5.5 SEQUOYAH UNIT 2, CYCLE 5 NORMALIZED AVERAGE AXIAL POWER DISTRIBUTION INC-5-F2-90-2A . . . . . . . . . 40 4.5.6 SEQUOYAH UNIT 2, CYCLE 5 NORMALIZED AVERAGE AXIAL ,

POWER DISTRIBUTION INC-5-F2-90-11A. . . . . . . . . 41 4.5.7 SEQUOYAH UNIT 2, CYCLE 5 LIMITING FQ AT EACH AXIAL POINT INC-5-F2-90-1B. . . . . . . . . . . . . . . . 42 4.5.8 SEQUOYAH UNIT 2, CYCLE 5 LIMITING FQ AT EACH AXIAL POINT INC-5-F2-90-2A. . . . . . . . . . . . . . . . 43 4.5.9 SEQUOYAH UNIT 2, CYCLE 5 LIMITING FQ AT EACH AXIAL POINT INC-5-F2-90-11A . . . . . . . . . . . . . . . 44 4.5.10 SEQUOYAH UNIT 2, CYCLE 5 K(Z) - NORMALIZED FQ(Z) AS A FUNCTION OF CORE HEIGHT . . . . . . . . . . . . . 45 4.5.11 SEQUOYAH UNIT 2, CYCLE 5 AXIAL FLUX DIFFERENCE LIMITS AS A FUNCTION OF RATED THERMAL POWER . . . . 46 v

1.0 Introduction and Cycle Deacription ~

Sequoyah unit 2 was shut down on September 8, 1990, ending its fourth cycle of operation. During the 75 day outage, 80 of the 193 fuel assemblies were replaced with fresh fuel. Ultrasonic fuel inspection identified leaking fuel rods in 4 assemblics scheduled for reinsertion, assemblies S15, S21, S27, and S61. >

Assemblies S15, S21, and S27 are symmetric counterparts and were discharged. Assembly S61 and three symmetric counterparts were

((} also discharged. In addition, visual inspections identified 18 instances of grid damage, one severe enough to discharge the assembly (assembly S20). Assembly S20 was the fourth symmetric counterpart for S15, S2g3 and S27. The 80 fresh fuel agggmblies consist of 56 3.60 w/o U assemblies and 24 4.20 w/o U assemblics of the Westinghouse Vantage SH type. The final core loading pattern is presented in Figure 3.2. Cycle 5 is the first application of the Vantage SH fuel in unit 2, and includes the A following new features; Zircaloy grids, reconstitutable top nozzles, integral fuel burnable absorbers (IFBA), extended burnup capability, and debris filter bottom nozzles.

The purpose of this report is to discuss the cycle 5 startup physics testing program. The startup tests are performed to verify that the core performs as designed. Tables 1.1 and 1.2 contain core design parameters and fuel specifications for cycle 5.

Cycle 5 utilizes 144 fresh burnable absorber rods of the wet annular-design in cluster patterns of 4 and 8. In addition, 7104 integral fuel burnable absorbers were used in patterns of 80, 100, and 128 rods per assembly. The neutron sources are located in 2 assemblies each containing 4 source rods. Core locations for the burnable absorbers, neutron sources, and control rods are indicated in Figure 1.1.

Cycle 5 has a projected full power capability of approximately 15,600 MWD /MTU (410 effective full power days, EFPD). The safety analysis for cycle 5 is valid up to a burnup of 16,600 MWD /MTU which includes a power coastdown. Operation of cycle 5 will have the flexibility of being governed by relaxed axial offset control (RAOC) .

l

Tabl.e 1.1 Sequoyah Unit 2, Cycle 5 Core Design Parameters Power Rating 3411 MWT Heat Generated in Fuel 97.4 %

Coolant Temperatures Hot Zero Power 547.0 F Design Inlet, Hot Full Power 546.7 F Design Core Average, Hot Full Power 582.2 F System Pressure 2250 psia Average Linear Power Density 5.43 kW/ft Specific Power 38.09 kW/KGU Power Density 103.79 kW/ liter Hot Channel Factor Limiting Heat Flux, FQ 2.32 Nuclear Enthalpy Rise, FDHN 1.55

Table 1.2 Sequoyah Unit 2, Cycle 5 Puel Specifications Number of Fuel Assemblies Region 4 9 Region-SA 24 Region SB 8 ,

Region 6A 40 Region 6B 32  ;

Region 7A 56 Region 7B 24 Total 193 Region Fuel Loading Region-4 4.14 MTU Region SA 11.08 MTU Region 5B 3.69 MTU

_ Region 6A 18.62 MTU Region 6B 14.91 MTU Region 7A 25.98 MTU

-Region 7B __11.12 MTU Total 89.54 MTU Enrichments (w/o U-235)

Region 4 3.50 w/o Region SA 3.80 w/o Region SB 3.60 w/o Region 6A 3.40 w/o Region 6B 3.60 w/o Region 7A 3.60 w/o Region 7B 4.20 w/o Active Fuel Height 144 inches

-Lattice Configuration 17 x 17 Lattice Pitch 0.496 inches Assembly-Pitch 8.466 inches No. of-Fuel Rods Per Assembly 264 No. of Instrument Thimbles per Assembly 1 No. of RCC Guide Thimbles Per Assembly 24 No. of Grids Per Assembly 8 Fuel Rod Outside Diameter 0.374 inches

Table 1.2 (Continued)

Clad Thickness 0.0225 inches clad Material Zircaloy-4 Pellet Diameter 0.3225 inches Wet Annular Burnable Absorbers 144 (Al 2O3-D 4C)

Integral Fuel Burnable Absorbers 7104 (ZrB2 coating)

R P N M L K J H G F t 0 C 8 A 1

SA CB CC CB SA 2 4W 4W 1001 1001 1001 1001 SD $8 SB SC 3

801 1281 1281 4S 1281 1281 Sol SA CD CD CD SA 4 BW 8W 1281 1281 1281 1281 SC SD 5 4W 4W 4W 4W 1001 1281 1001 1281 1001 CB CC CA CC CB 6 4W 4W 1281 1001 1D01 1281 SB SB 1 BW 4W 4W BW 1001 1281 1001 1001 1001 1281 1001 CC CD CA ' CD CA CD CC 8

1001 1001 1001 1001 SB SB 9 BW 4W 4W BW 1001 1281 1001 1001 1001 1281 1001 CS CC CA CC CB

.0 4W 4W 1281 1001 1001 1281 SD SC 11 4W 4W 4W 4W 1001 1281 1001 1281 1001 SA CD i CD CD SA 12 l W BW 1281 1281 1281 1281 SC 58 $8 SD 13 AS 801 1281 1281 1281 12Li 801 SA CB CC CB SA '

14 4W 4W 1001 1001 1001 1001 d

M T01 AL CA, CB, CC, CD, SA, 50, SC, SD...(RCCAs)...... 53 W....(WABAS)........ ......................... 144 1....(IF8As).. ... ......... ............... . 7104 S....(SECONDARY SOURCE R00 LEIS)........ ..... 8 FIGURE 1.1 SEQUOYAH UNii 2 CYCLE 5 CORE COMPONENT CONFIGURATION 5-

2.0 Test Procram Summary This report covers the period from September 21, 1990 through December 31, 1990. Significant milestones for this period are summarized as follows:

Start of Core Unload September 21, 1990 End of Core Reload October 11, 1990 Initial Criticality November 12, 1990 Completion of Zero Power Physics Testing November 21, 1990 Initial Power Generation November 22, 1990 Power Escalation to 30-percent Power November 22, 1990-Power Escalation to 70-percent Power November 30, 1990 Power Escalation to 100-percent Power December 6,-1990 Achieved Core Burnup of 32 EPPD December 31, 1990 Table 2.1 summarizes the startup physics tests that were performed during cycle 5 startup. Reactor power histograms for November 1990 and December 1990-are shown in Figures 2.1 and 2.2, respectively, with significant events summarized in Table 2.2.

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• Westinghouse Proprietary Class 2 4.0 Core Performance The operational power capabilities of Sequoyah Nuclear Plant are governed by limits imposed by the safety analysis, as presented in the Sequoyah Updated Final Safety Analysis Report (UFSAR).

Various core parameters were measurou during the restart physics testing to ensure the conservatism of assumptions made in the safety analysis and to verify the core performed as designed.

The following sections discuss the results of the core physics tests.

4.1 Initial Criticality Initial criticality was achieved on November 32, 1990 at 1730 EST. The reactor coolant system temperature a..d pressure were about 547 F and 2235 psig, respectively. The soluble boron concentration was 1513 ppm, and all rod control banks were fully withdrawn with the exception of control bank D, which was at 200.5 steps. The corrected critical boron concentration for control bank D at 200 steps was 1513 ppm. The acceptance critorion for_ critical boron concentration with control bank D at 200 steps was [ ] 1 130 ppm. a,c The approach to criticality proceeded in a safe and judicious manner. Starting with the shutdown banks withdrawn and 1751 ppm and the reactor coolant at about 547 F and and 2235 psig, control rod withdrawal commenced. During-rod withdrawal, inverse count rate ratio data was recorded and plotted for source range detectors N-31 and N-32 (Figures 4.1.1 through 4.1.2). When control-banks A, B, and C were-fully withdrawn and control bank D was positioned at about 200 steps, boron dilution was initiated.

Again inverse count rate ratio plots were recorded (Figures 4.1.3 through 4.1.8). The reactor coolant was diluted until criticality was achieved.

In addition to bringing the reactor critical for the first time, the initial criticality procedure accomplished several other objectives. The neutron flux level at which nuclear heating first occurred was determined, thus establishing a range below nuclear heating at which all zero power physics measurements were performed. The calibration of,the reaqtivity computer was verified by comparing its output to several positive and negative reactor periods.

4.2 Core Depletion The primary coolant critical boron concentration is monitored for the purposes of following core reactivity and identifying any anomalous reactivity behavior. If necessary, the measured Westinghouse Proprietary Clano 2 critical boron concentration is adjusted to nominal 100-percent operation conditions taking into consideration contro) rod position, xenon and samarium concentrations, moderator temperature, and power level. Figure 4.2.1 shows the design boron letdown curve and the measured critical boron concentration versus burnup to about 32 EPPD in cycle 5.

] 4.3 Beactivity contrM Excess reactivity is controlled by neutron absorbing control rods, boric acid dissolved in the reactor coolant and burnable absorbers. Both the control rod position and the boron concentration may be adjusted separately or in conjunction with one another to compensate for various reactivity changes and to

]} maintain the required shutdown margin. Rod bank and boron reactivity worths are measured at hot zero power (HZP) for comparison with design predictions.

4.3.1 Control Rod Bank Worib_Measurementn Control rod bank worth measurements for cycle 5 were determined using the Westinghouse rod swap procedure. This replaces the standard boration/ dilution method for determining the integral and differential worths of each control rod bank.

The rod swap procedure starts with the measurement of the reference bank worth using the boron exchange technique. After establishing an equilibrium condition with the reference bank inserted, each remaining rod bank is inserted and the reactivity change is compensated by withdrawing the reference bank. For the cycle 5 loading pattern, control bank D was used as the reference bank. The measured integral worth of control bank D was 1102.7 pcm, which met the acceptance criteria of ( ) i 162 pcm. n.c Figures 4.3.1 and 4.3.2 provide plots of the integral and differential worth of control bank D. Table 4.3.1 shows a comparison of measured and predicted rod worths based on the rod swap.

4.3.2 poron Worth and EDdpoint Measurements Reactor coolant system boron measurements were made during zero power physics testing to determine differential boron worth and concentration endpoints for the ARO configuration. The differential boron worth measured over the range of control bank D at HZP was -7.95 pcm/ ppm. The measured differential boron worth was within the review criteria of ( ) i 1.17 pcm/ ppm. a,c The boron endpoint was established for the ARO configuration.

The boron endpoint value includes corrections to the measured data to account for differences between the critical

. Westinghouse Proprietary Clo.ss 2 configuration and the endpoint configuration. The ARO boron endpoint was calculated to be 1527 ppm, well within the review criteria of ( ) i 50 ppm. a,e 4.4 Jsothermal Temperatilre Coefficient McAnute_Inanta;i The isothermal temperaturo coefticient (ITC) was measured during zero power physics testing to verify a negative T.oderator temperature coefficient (MTC) as required by Technical Specifications. The ITC is defined as the change in core reactivity per unit change in moderator, clad, and fuel temperatures. From the measured ITC, a value for the MTC is obtained from the relationship:

MTC = ITC - Doppler Coctficient s The predicted hot zero power beginning of cycle Doppler coefficient was ( ) pcm/F. a,c This measurement was performed by heating un and cooling down the primary system by regulating steam dump to the atmosphere or the condenser over the range of 543 to 546 F. During the heatup and cooldown, an X-Y recordtr was utilized to plot the change in reactivity with respecu to the changes in the primary system temperature. The slope of this curve of Tavg versus reactivity is the ITC.

Measurements of the ITC were taken for D bank at 213 steps. The ITC measured during heatup and cooldown wero ~2.98 and -2.66 pcm/F respectively, with an average of -2.82 pcm/F at a Tavg of 544.8 F. When corrected to a temperature of 547 F and ARO, the ITC was found to be -2.90 pcm/F which is within the acceptance criteria of ( ) i 2 pcm/F. When conservatively corrected to a a,c Tevg of 541 F, the corrected ITC is -2.38 pcm/F. The corresponding conservative MTC was -0.48 pcm/F which is within the acceptance criteria of < 0 pcm/F.

4.5 Eower Distriby_ tion Measurements Analysis of core power distribution data during startup' test'ing is necessary to verify proper core loading, design calculations, compliance with Technical Specifications, and the relationship between incore power distributions and excore detector responses.

Three-dimensional core power distributions are determined from moveable detector flux trace measurements using the INCORE computer code.

Table 4.5.1 summarizes representative INCORE flux maps for the startup of unit 2, cycle 5. This table includes the core

conditions at the time of the measurement and INCORE results for the maximum heat flux hot channel factor (excluding uncertainties) FQN(z), the maximum nuclear enthalpy rise hot channel factor FDHN, incore quadrant power tilt ratios (QPTR) ,

and axial offsets. Note that the maximum peaking factors ,

identified in Table 4.5.1 are useful from a core design standpoint, but are not necessarily the most limiting according to Technical Specifications since they do not indicate reduced margina associated with the W(z) and K(z) functions or uncertainty tolerances.

4.5.1 Assemb1v Power Distributions Power distribution measurements were made during startup testing at 30-percent power, 70-percent power, and 100-percent power.

Relative assembly power is analyzed with respect to the difference between designed and measured values. Figures 4.5.1 through 4.5.3 provide an assemblywise relative power distribution for all the flux maps described in Table 4.5.1. Also included in these figures are comparisons between measured and designed assembly powers including the RMS difference, the RMS percent difference, the RMS difference for assemblies above 1.0 relative power, the out-in power tilt (power in the outer two rings of assemblies vs. the power in the center) , the incore quadrant power tilt and the maximum percent difference between symmetric assemblies.

When the 30-percent power flux map was recorded and compared to predictions, all review criteria were met. Flux maps were also recorded at 70-percent and 100-percent power.

Figures 4.5.4 through 4.5.6 illustrate the normalized core average axial power distributions for each flux map.

4.5.2 Fa(z) Surveillance The Technical Specification limit for Fq(z) at full power is 2.32. Fq(z) surveillance involves the use of the parameter K(z).

K(Z) is Fq(z) normalized to the maximum value allowed at any core height. The parameter K(z) is given in Figure 4.5.10 for unit 2, cycle 5 operation. Operation of cycle 5 has had the added i flexibility of Relaxed Axial Offset Control (RAOC). Figure 4.5.11 represents the acceptable RAOC delta-I operation limits used in cycle 5. The Technical Specification surveillance requirement on Fq(z) incorporates potential changes from the equilibrium power distribution by using a transient function W(z). W(z) accounts for the effects of normal operational transients and is determined from calculated power control maneuvers over the full range of burnup, power, and axial flux difference conditions. The Fq(z) limit of 2.32 is multiplied by K(z)/W(z) and then compared with the measured Fq(z) values.

si _.-_

- Figures 4.5.7 L through 4.5.9 illustrate the Fq(z) limit and limiting value at each axial point for each_ flux map.

4.5.3 FDHN Surveillance i

FDHN surveillance is accomplished by comparison of the measured FDHN to the FDHN limit defined by plant Technical Specifications.

The Technical Specification l'imit for FDHN at full power is 1.55.

The measured value of FDHN obtained in each flux map was verified to be within Technical: Specification limits.

.4.5.4 -Incore-Excore Calibration  !

Calibration.of the nuclear-instrumentation system (NIS),

comprised of-six moveable incore detectorsuand eight stationary' excore detectors,_ is required for each core reload. For this i cycle, calibrations'were_ performed for startup, at 30-percent power, and'at-70-percent. power. The calibration at 30-percent was a single point alignment. Calibration checks were performed on,the Intermediate Range. channels at 50-percent and-100-percent-power. A calibration was required at 50-percent power.

-To obtain the data required to calibrate the'NIS excoro. power rangecdetectors at power, an axial xenon oscillation is induced in1the core by inserting control. bank D. LAfter about 5-hours, 1 control bank D is withdrawn to its starting position and_the xenon oscillation is allowed to swing delta-I without any ,

adjustments in bank.D position.

Full-core' flux maps are-taken along with associated NIS and

-calorimetric data. prior to the oscillation-and at-the peak-of the delta-I swing. From-this data the power range-channels N-41 through-N-44 were calibrated.

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0 25 50 75 100 125 150 175 200 225 250 Rod Bank Position (Steps Withdrawn)

Figure 4.3.1

4 SON 2 Cycle 5 Differential Bank D Worth BOL, HZP, NO XE 4

8 -

h  % i D

i l , , j l s 7 _ . . .

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f i .-  : i e  ;

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0 25 50 75 10 0 125 15 0 175 200 225 250 Rod Bank Position (Steps Withdrawn)

Figure 4.3.2

. ._.,.--,_-_.___,-~_-.~_._._-.--____....~...____._..___..-.n_-._.._.._ .

~

k'estinghouse Proprietary Class 2 .

TAstr 4.5.1 SEQUOYAM UNIT 2 CYCLE 5 INCORE FLUX PAP SLHMRf RADIAL AX1AL MAX RADIAL CPTR* AXIAL BANK PCNTR PtJRNt? PAX LOCATION N41 M42 N43 h44 CFFTET DATE INC-5-F2- 0 LEVEL K'D/MTU FCN(2) t0CAff04 POINT FDP4 a,c

- - a,c - - a,c p 11/27/90 90-18 167.0 27% 22 N 6NM 30 N 6(M 1.0101 0.9797 1.0040 1.0062 12/ 2/90 90-2A 210.0 71% 135 m 6%M 31 N 6NM 1.0067 C.9333 1.C026 1.0052 t

219.5 307 m 6NM 40 N 6hM 1.0039 0.9399 1.C^06 1.0056 d

I 12/ 8/90 90-11A 100%

• Reistive Locations of Excore Detectors: N41 I N43 N44 l N42

k'e t; t inghou se Proprietary Clatir. 2 n,c i

FIGURE 4.5.1 StouOYAH UNIT 2 CYCLE 5 Rtt Alivt AS$tMnty Pcotts INC-$ F2 90 1B 1

. t "g _

l 1

i i-POWER DISTRIBUTION PARAMETERS INC-5-F2-90-1B RMS DIFF = 0.03109 RMS % DIFF = 3.2423 RMS DIFF FOR ASSY > 1.0 RPD = 0.03148 POWER OUT (EXPECTED) = 0.8533 POWER OUT (MEASURED) = 0.8486 POWER IN (EXPECTED = 1.1131  :

POWER IN (MEASURED) = 1.1166 -

l MEASURED QUADRANT POWER TILTS 1.0100 1.0040 1.0062 0.9797 EXPECTED QUADRANT POWER TILTS i 1.0000 1.0000 1 1.0000 1.0000 SYMMETRIC ASSEMBLY % DIFFERENCES 1 0.00 1.47 2.81 6.54 5.47 5.03 2.68 2.63 !

1.47 3.78 5.82 5.53 5.84 4.74 4.10 4.63 2.81 2.83 3.73 1.80 6.32 5.65 12.88 11.51 i 4

6.54 4.54 0.80 2.74 4.91 6.17 14.32 13.77 5.47 4.43 1.47 1.68 5.00 8.51 13.71 5.03 4.06 4.61 3.36 8.C6 3.47 7.05 2.68 4.16 3.71 4.00 6.92 5.77 2.63 6.31- 4.10 3.87 i

FIGURE 4.5.1 (cont.)

i i  !-

Westinghouse Proprietary Class 2 a,c s

FIGURE 4.5.2 SEQUOYAH UWii 2 CYCLE 5 RELATIvt Ass [ MOLY POWERS INC-5 F2 90 2A

_. 3 9

POWER DISTRIBUTION PARAMETERS INC-5-F2-90-2A RMS DIFf = 0.02299 RMS % DIFF = 2.4431 RMS DIFF FOR ASSY > 1.0 RPD = 0.02266 POWER OUT (EXPECTED) = 0.8429 POWER OUT (MEASURED) = 0.8354 POWER IN (EXPECTED = 1.1211 POWER IN (MEASURED) = 1.1268 MEASURED QUADRANT POWER TILTS 1.0068 1.0026 1.0052 0.9854 2XPECTED QUADRANT POWER TILTS 1.0000 1.0000 1.0000 1.0000 SYMMETRIC-ASSEMBLY % DIFFERENCES 0.00 2.42 2.14 5.21 5.60 3.98 3.02 2.49 2.42 4.95 5.19 4.52 5.06 3.75 3.22 2.00 2.14 2.87 3.20 1.90 4.31 4.06 9.75 8.51 5.21 2.85 0.54 2.42 3.14 4.05 11.95 11.45 5.60 4.70 1.05 2.57 2.70 6.07 10.30 3.98 3.49 3.83 2.97 2.94 1.98 5.91 3.02 3.34 3.13 2.95 6.57 4.10 2.49 4.43 3.39 2.93 FIGURE 4.5.2 (cont.)

i l i 1

l

Westinghouse l'roprietary Class 2 a,c

~

FIGURE 4.5.3 SEQUOYAH UNii 2 CYCLE 5 RELAfivE ASSEM3tY Poutes INC 5 F2 90 11A

~37-

l l

l l

POWER DISTRIBUTION PARAMETERS INC-5-F2-90-11A RMS DIFF = 0.01818 RMS % DIFF = 1.9246 RMS DIFI; FOR ASSY > 1. 0 RPD = 0. 01804 POWER OUT (EXPECTED) = 0.8428 POWER OUT (MEASURED) = 0.8330 POWER IN (EXPECTED = 1.1219 POWER IN (MEASURED) = 1.1281 MEASURED QUADRANT POWER TILTS 1.0039 1.0005 1.0057 0.9899 EXPECTED QUADRANT POWER TILTS

-1.0000 1.0000 1.0000 1.0000.

SYKMETRIC ASSEMBLY % DIFFERENCES 0.00 0.87 2.38 5.02 4.43 4.11 3.22 2.92 0.87 3.34 4.37 3.93 3.76 3.42 2.06 0.68 2.38 1.85 2.48 1,54 3.05 3.52 7.38 6.04 0.02- 2.55 1.07 1.54 2.34 3.55 9.26 8.72 4.43 4.12 2.29 1.42 1.49 4.21 7.84 4.11 3.88 3.78 1.22 2.51 0.43 4.31 3.22 3.26 3.86 1.30 4.47 3.26 2.92 3.97 3.97 0.92 FIGURE 4.5.3 (cont.)

f

Westinghouse Proprietary Class 2

.I i

n,c J

1-

+

1 9

flGURE 4 $.4 stouGYAH UNIT 2 CYCLE $ NORMAllHD AVERAGE AXIAL POWER Di$fRIDufl0W INC 5 F2 90 18

-39 g-y., ,-gy#.49,wgy g, - -

ye-- - y .y 2-w---

7%.-W'4 ,w y y -- yy.-vee--- .g-. ,, ,%-.,we, , , , , s+3+-- m9w,,.r,g,- - .yy. 9

We fi t i ng,lio u f,0 Ptoprietary ClaHB 2 a,c flGURE 4.5.5 $EQUOYAH UNii 2 CYtti 5 WORMAtl2tn AVERiaE AXt AL MMR DISTRIBUTION INC-5 f2-90 2A s

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Wer.tinghouse Prepriccary Clasu 2 ,

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9 FIGUR[ 4.5.6 stou0VAH UNIT 2 CYCLE 5 NORMAL!![D AVERAGE AXIAL N MER DISTRIBUTION

.INC $ f2 90 11A s

9" ) W 4 "F*I V gm"" Wl'WT- ,p, ,w,a y,.p,,,_,,m..,,,, r,p,p.,_,,,,__,gg _ , , , , , , , _ _ ,

i Welit ing,houtte l't oprieta ry Claus 2 l

a,c flGtRF.4.5.7 stopoVAH UNIT 2 CYCLE $ LIMlilNG F0 Ai [ACH AXIAL POINT INC 5 F2 90 19 l

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Westinghouse Ptoprietary Class 2 l l

l a,e t

t FIGURE 4.5.8 stouoVAH UNIT 2 CYCLE 5 LlHITING Fo AI EACH AX1AL iglNT IWC+5 F2 90 2A j.

1

r- 1 e

West iny, hour.c l'roprietat y Clusti 2 1

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FIGURE 4.5.9 $EQUOYAH UN!I 2 CYCLE $ LlHl(ING F0, At E ACH !,rl AL PolWT .

IWC 5 f2 90 11A

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'20 5 6 7 8 9 10 11 12 O 1 2 3 4 tottee N M1 UEEO Top 1

Fo Normallred Operating Envelope, K(Z) as a Function of Core Height

-45

r 3 l'Ir,ure 4. 5.11 9

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0 50 -40 -30 -20 -10 0 10 20- 30 40 50 Flux Difference (61):

1 AXIAL FLUX 01FFE3ENCE LIMITS AS A FUNCTION OF RATED THERFAL POWER

~46-

_ - - .._._ _ _ _ . _ _ _ ,__ . . _ _ . . . - _ _ _ _ _ . _ , . . . . . . _ _ _ - _ _ . _ ..