ML17228A295

Cycle 12 Startup Physics Testing Rept

ML17228A295
Person / Time
Site:	Saint Lucie
Issue date:	09/01/1993
From:	Jimenez M, Mead W, Wachtel P FLORIDA POWER & LIGHT CO.
To:
Shared Package
ML17228A294	List: L-93-236, Forwards St Lucie Unit 1,Cycle 12 Startup Physics Testing Rept ML17228A295
References
NUDOCS 9309160163
Download: ML17228A295 (19)

Text

9309160163 930910 PDR ADOCK 05000335 P

PDR (PRES4WAN)

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St. Lucie Unit 1, Cycle 12

>et>ev M2M~ ~ChdM Patricia Wachtel Reactor Engineering, St. Lucie Plant Date~~g~~

Reviewed M~ J. 7i~

Walter D. Myoid,jr Reactor Engineering, St. Lucie Plant Date Reviewed

~PdS~

Modesto Jimenez Reactor Support Supervisor, Nuclear Fuel Approved Erwin J. Wunderlich Reactor Engineering Supervisor St. Lucie Plant D,, zg~y'~e

~l l~~

Date Page 2 of16

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St. Lucie Unit 1, Cycle 12 Table of ContentsSection I

II III IV V

VI VII

~Pa e

4 4

5 5

7 7

8 Title Introduction Cycle 12 Fuel Design Approach to Criticality Zero Power Physics Testing Power Ascension Program Summary References List of Fi ures Fi ure No.

Titles 9

10 10 11 12 13 14 Cycle 12 Core Loading Pattern Inverse Count Ratio Plot-Channel B

Inverse Count Ratio Plot-Channel D

RCS Boron Dilution Plot Power Distribution-25% Power Power Distribution-50% Power Power Distribution-100% Power List of Tables Table No.

Title 15 15 16 Cyde 12 Reload Sub-Batch ID Approach to Criticality Comparison of SPCND Calculations with Measured Values Page 3 of-16

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St. Lucie Unit 1, Cycle 12 I.

Introduction The purpose of this report is to provide a description of the fuel design and.

core load, and to summarize the startup physics testing performed at St. Lucie Unit 1 following the Cycle 12 refueling. Startup physics testing verifies key core parameters are as predicted.

The major parts of this tesbng program are:

1) Initial Criticality following reload,

2) Zero Power Physics Testing and,

3) Power Ascension Testing.

II.

C cie12 Fuel Desi The Cycle 12 core consists entirely of fuel manufactured by Siemens Power Corporation Nuclear Division (SPCND).

The 217 assemblies in the Cycle 12 core are comprised of fuel from three batches.

Of these, 84 are fresh batch R assemblies consisting of natural uranium axial blanket assemblies, 84 are once burnt batch P assemblies consisting of 76 natural uranium axial blanket assemblies and 8 Vessel Fluence Reduction Assemblies (VFRAs), and 49 are twice burnt batch M assemblies.

A further breakdown of the distinct sub-batches is contained in Table 1.

This is the sixth cycle of operation utilizing gadolinia, in the form of Gd>O3, as a burnable absorber, coupled with the use of natural uranium blankets at the top and bottom of each fuel assembly.

"The batch R fuel is the fifth cycle of fuel provided by SPCND that uses long lower end-caps as a means of providing protection against debris fretting in the Lower End-Fitting region.

The Cycle 12 core map is represented in Figure 1.

The assembly serial numbers and Control Element Assembly (CEA) serial numbers are given for each core location. As in Cycle 11, the Cycle 12 reload employs a low-leakage design that relies on batch M fuel around the periphery, augmented with VFRAs in the core flats to further reduce the fluence on the reactor vessel welds for life extension purposes.

Each VFRA is constructed to the design of a standard fuel assembly with the exception of the fuel pellets loaded in each fuel rod.

The VFRA design utilizes depleted uranium instead of the standard reload enrichments.

In addition, each of the outer four guide tube finger holes is loaded with a full-length hafnium insert to further suppress the flux at the vessel boundary.

Page 4 of 16

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St. Lucie Unit 1, Cycle 12 Following the fuel shuffle and prior to the approach to criticality, CEA drop time testing was performed.

The objective of this test was to measure the time of insertion from the fully-withdrawn position (UEL) to the 90% inserted position under hot, full-flowconditions.

The average CEA drop time was found to be 2.30 seconds with maximum and minimum times of 2.50 seconds and 2.14 seconds, respectively.

All drop times were within the requirements of Technical Specifications 3.1.3.4 (i.e. less than or equal to 3.1 seconds).

III. A roach to Criticali The approach to criticality involved diluting from a non-critical boron concentration of 1633 ppm to a predicted critical boron concentration of 1408 ppm.

The actual critical concentration was observed to be 1377 ppm. Inverse countrate ratio (ICRR) plots were maintained during the dilution process using wide range channels B and D.

Refer to Figures 2 and 3 for ICRR information, Table 2 summarizes the dilution rates and times, as well as the beginning and ending boron concentrations.

Initial criticalityfor St. Lucie Unit 1, Cycle 12 was achieved on May 29, 1993 at 0421 with CEA group 7 at 60 inches withdrawn and all other CEA's at the all rods out (ARO) position, IV. Zero Power Ph sics Testin The purpose of the Zero Power Physics Testing program is to verify that the core operating characteristics are consistent with the design predictions and to provide assurance that the core can be operated as designed.

The major tests performed for the startup of Cycle 12 were the following:

1) Reactivity Computer Checkout

2) CEA Symmetry Test

3) AllRods Out Critical Boron Concentration

4) Isothermal Temperature Coefficient Measurement

5) CEA Group Rod Worth Measurements Page 5 of 16

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St. Lucie Unit 1, Cycle 12 The tests above were performed in accordance with approved procedures Zero Power Physics Testing started on May 29, 1993, following initial criticality. Following the Reactivity Computer Checkout, the CEA Symmetry Test commenced.

The initial test showed indications of a possible unlatched CEA and the Unit was returned to cold shutdown conditions, the reactor was disassembled, and the CEA was relatched.

Criticality was achieved, again, on June 11, 1993, and Zero Power Physics Testing was reinitiated on June 12, 1993.

Proper operation of the Reactivity Computer was verified for a second time through the performance of two tests. In the first, reactor power was elevated sufficiently high to ensure maximum sensitivity of the reactivity measuring system and at the same time preserve adequate margin to the point of adding heat.

The second test ascertained response to a known value of positive or negative reactivity by measuring the values of positive or negative reactor periods that result.

The results of the Reactivity Computer checkout were compared to the appropriate predictions supplied by the fuel vendor. Satisfactory agreement was obtained.

Verification of proper CEA latching was confirmed through the use of the CEA Symmetry Test utilizing the Unit 1 Shutdown Groups A and B which contain

=dual CEA's. The prescribed acceptance criteria was that the reactivity measured for each dual CEA shall be within + 15.0 pcm of the average reactivity measured for the entire group.

There were no unlatched CEA's for either Shutdown Group.

The All Rod's Out Critical Boron concentration was performed.

The measured value was 1418.7 ppm which compared favorably with the design value of 1456 ppm, This was within the acceptance limits of k 100 ppm.

The measurement of the Isothermal Temperature Coefficient was performed and the resulting Moderator Temperature Coefficient (MTC) was obtained, The MTC was determined to be +1.54 pcm/'F which fell well within the acceptance criteria of 2 2.0 pcm/'F of the design MTC of +1.38 pcm/'F (corrected).

This agreed favorably with the Unit 1 Technical Specification 3.1.1.4 which states that the MTC shall be less positive than 7.0 pcm/'F.

The final section of interest for low power physics testing is in the measurement of CEA Group Rod Worths.

Rod worth measurements were performed using the Rod Swap methodology.

This method involves exchanging the reference group, measured by the boration dilution technique, with each of the remaining test groups. A comparison of the measured and design CEA reactivity Page 6 of 16

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0 St. Lucie Unit 1, Cycle 12 worths is provided in Table

3. The following acceptance criteria apply to the measurements made:

1) The measured value of each test group is within %15% or 2100 pcm of the design CEA worths, whichever is greater.

2)

The measured worth of the Reference Group, and the total worth for all the CEA groups measured is within 210% of the total design worth.

Allacceptance criteria were met in that the Reference Group measured worth was within 210% of design worth and each test group was within +15% or 2100 pcm of design worth.

V.

Power Ascension Pro ram During Power Ascension, the fixed incore detector system is utilized to verify that the fuel is loaded properly and there are no abnormalities occurring in the various core parameters (core peaking factors, LHR, and Tilt) for power plateaus at 25%, 50%, and >98% rated thermal power.

Calorimetric, Nuclear, and hT power calibrations were performed at each of the plateaus prior to advancing reactor power to the next higher power level.

A summary of the results of the flux maps at each power level is provided in Figures 5, 6, and 7.

1 Within seven days of attaining 100% power, the Hot Full Power (HFP) MTC test was performed by maintaining power constant and varying temperature.

The center CEA, 7-1, was inserted to permit compensation of the resulting reactivity changes.

The HFP MTC was measured to be -5.7772'pcm/'F which was within +2.0 pcm/'F of the design value of -4.2810 pcm/'F.

This test also verified compliance with Technical Specification 3.1.1.4 which requires the measured MTC be less negative than -28.0 pcm/'F and less positive than 2.0 pcm/'F while thermal power is greater than 70%.

VL ~Summar A second rod drop test was performed, prior to reaching criticality on June 11.

The results of that test were consistent with the previous test conducted in May.

The average CEA drop time'was 2.36 seconds and the maximum and minimum times were 2.54 seconds and 2.22 seconds, respectively.

Compliance with the applicable Technical Specifications was satisfactory for all tests.

Page 7 of 16

St. Lucie Unit 1, Cycle 12 VII. References 1)

"St. Lucie Unit 1, Cycle 12 Startup and Operations Report,"

EMF-93-076(P),

dated April,1993.

2)

"Initial Cr'iticality," Pre-Operational Test Procedure Number 1-3200088, Revision 3.

3)

"Reload Startup Physics Testing," Pre-Operational Test Procedure Number 3200091, Revision 1.

4)

"Reactor Engineering Porkier Ascension Program," Pre-Operational Test Procedure Number 3200092, Revision 3.

5)

St. Lucie Unit 1 Technical Specifications.

Page 8 of 16

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St. Lucie Unit 1, Cycle 12 FIGURE 1 CYCLE 12 CORE LOADINGPATTERN Y

X W

V T

S P

M K

H J

I G

F E

D C

B A

FROB M21 a

b d

c M18 FR04 a

b d

c 21 M13 R01 POS RO5 124 R03 125 P07 R07 M12 20 Mlo R21 129 RO9 P12 MBO R17 126 R25 201 P29 R33 R73

':: P38,.;-.

116

.'c k>+4 P16 R78 122 P42 M92 81 R49 127 R65 118 P66 R41 R29 M03 P75 R59 120 R37 M33 A51 123 R67 117 P10 R76 119 P39 M90 82 R19 128 R35 R83 115 M57 R24 130 P13 M16 R12 19 18 17 FA01 a

d c

M19 FR05 a

b d

c R13 133 R15 136 R53 131 Mol R32 301 M07 R55 101 R62 105 M31 R64 111 P74 R40 P72 114 R45 P17 P48 107 R84 110 P'l9 R47 P23 i RBO,",

P46 132 M87 135 P49 P45 99 R81 109 R82 103 P70 113 P24 R48 P47 106 M27 P71 P61 98 P18 R46 R69 83 M32 R39 M35 R71 84 R61 108 P73 R63 102 R56 112 R31 303

PBO,'54 R16 134 R14 137

'a'~..",.b-.:~c

.M23.'.

FA02 a

b d

c 15 14 13 12 11 10 9,

8 R 1 1 P14 M15 R23 138 R75 96 P35 R36 M89 95 P64 R44 R60 93 M26 R42 R38 M29 R58 92 M91 85 P41 R34 R74 94 Pll R22 139 Rlo

M09, M58 R28 203 P31 R77 91 RBB 90 P76 R66 89 R79 88 R26 69 M55 R20 140 P09 R52 M04 87 R30 M06 304 R50 F02 P15 R18 141 Ml1 R06 POB R04 142 ROB 143 PO6 R02 M14 FR&,

M17 M22 FA07

'a'.:'~': b a

b d:I"c' c

Page S of16

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St. Lucie Unit 1, Cycle 12 HGURE 2 WIDERANGECHANNELB BORON DILUTION 1.0 0.9 0.9 0.8 0.8 0.7 0.7 0.6

$ 0.5 D

0.4 0.6 0.5 0.4 0.3 0.3 0.2 0.2 0.1 0.1 1.0 GALLONSDILUTED FIGURE 3 WIDERANGECHANNELD BORON DILUTION 1.0 0.9 0.9 0.8 0.8 0.7 0.7 0.6 0.6

~0.5 O

0.4 0.5 0.4 0.3 0.3 0.2 0.1 GALLONSDILUTED Page 10 of 16

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St. Lucie Unit 1, Cycle 12 FIGURE 4 RCS BORON DILUTION BORON CONCENTRATIONVS. GALLONSDILUTED 165 162

~159 CI p 156 0p 1153

~150 UO147 gc144 141 138 165 62 59 56 53 50 47 41 38 135 PZ Eel 135 GALLONSDILUTED Page 11 of 16

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St: iucie Unit 1, Cycle 12 FIGURE 5 POWER DISTRIBUTION COMPARISON WITH DESIGN AT 25% POWER MEASURE: (CECOR/~INPA UNIT 1

SNAPSHOT ID¹ POWER LEVEL EXPOSURE CEA POSITION BORON CONC.

0/

EFPH 22.25 1 'PM DESIGN:

DATASOURCE:

POWER LEVEL EXPOSURE CEA POSITION BORON CONC EMF-93-076(P)

EFPH 2

N 60 PPM 0.8260 0.8390

-0.0130 2

1.0720 1.0890

-0.0170 1.0300 1.0410

-0.0110 1.1210 1.1440

-0.0230 1.1340 1.1580

-0.0240 1.1610 1.1790

-0.0180 0.7260 0.7480

-0.0220 0.9830 1.0150

-0.0320 1.0200 1.0530

-0.0330 3

0.8090 0.8440

-0.0350 4

1.1470 1.1580

-0.0110 3

0.4000 0.4070

-0.0070 1.3080 1.3150

-0.0070 2

1.1320 1.1400

-0.0080 3

1.1830 1.1980 4.0150 0.4290 0.4680

-0.0390 3

1.0780 1.0880

-0.0100 2

1.2330 1.2310 0.0020 1.2280 1.2210 0.0070 2

.1.1020 1.1060

-0.0040 2

1.2030 1.2040

-0.0010 2

1.1420 1.1280 0.0140 21 1.3070 1.2870 0.0200 2

1.0010 0.9830 0.0180 0.8090 0.8160

-0.0070 1.2300 1.2160 0.0140 0.9980 0.9750 0.0230 1.3040 1.2500 0.0540 1

1.1120 1.1310

-0.0190 1.1030 1.0940 0.0090 6

1.2900 1.2500 0.0400 7

1.0700 1.0060 0.0640 8

~KEY MEASURED DESIGN DELTA RMS DEVIATION ~gg~o 0.1000 0.3490 0.0970 0.3350 0.0030 1

0.0140 g

Page 12 of 16

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St. Lucie Unit 1, Cycle 12 FIGURE 6 POWER DISTRIBUTION'OMPARISON WITH DESIGN AT 50% POWER MEASURE: (CECCRI~NPAX I ttlttttt tlst UNIT 1

DESIGN:

DATASOURCE:

POWER LEVEL EXPOSURE CEA POSITION BORON CONC PPM 1.0870 1.1110

-0.0240 0.7570 0.7770

-0.0200 1

1.1390 1.0120 1.1710 1.0440

-0.0320 1

-0.0320 1.1500 1.0400 1.1850 1.0800 4.0350 1q

-0.0400 3

1.3080 1.3030 0.0050 2

0.8470 1.0460 0.8550 1.0640

-0.0080 2

-0.0180 1.1000 1.2190 1.0950 1.2180 0.0050 2

0.0010 1.1710 0.8160 1.2070 0.8680 4.0360 1

-0.0520 0.8300 1.138p 0.8360 1.1480

-O.OO6O 1

-O.O1OO 6

1.1350 1.1420 1 257p 1 154p 1.1350 1.1260 1 224p 1 13pp 0.0000 3

0.0160 3

0.0330 2

0.0240 2q 0.3810 1.2080 1.27gp 1.324p 0 4000 1 1730 1.2030 1.2740

-0.0190 3

0.0350 3]

0.0760 2

0.0500 0.4790 1.1380 1.pp4p 0 4620 1.0820 p.g67p 0.0170 3

0.0560 2

0 0370 2

1.2470 1.2230 0.0240 1.0040 0.9790 0.0250 1.2760 1.2430 0.0330 1.1330 1.1010 0.0320 6

1.2820 1.2450 0.0370 1.0290 1.0010 0.0280 8

~KEY MEASURED DESIGN DELTA ID RMS DEVIATION~ ~gg1 0.1010 0.0990 0.0020 0.3470 0.3410 0.0060 9

Page 13 of 16

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St. Lucie unit 1, Cycle 12 FIGURE 7 POWER DISTRIBUTION COMPARISON WITH DESIGN AT 100% POWER MEASURE: (CECOR/INPAX)

UNIT 1

SNAPSHOT ID¹ POWER LEVEL EXPOSURE CEA POSITION BORON CONC.

880 7

PPM DESIGN:

DATASOURCE:

POWER LEVEL EXPOSURE CEA POSITION BORON CONC MF-EFPH 1.1910 1.2240

-0.0330 1.1290 1.2010 1.1540 1.2310

-0.0250 1

-0.0300 11 0.8290 0.8520 0.0040 1.0760 1.1050

"-0.0290 1.0960 1.1310

-0.0350 3

0.8770 1.0760 1.2080 0.8850 1 0990 1.2450

-0.0080 2

-0.0230 1

-0 0370 0.8640 0.9140

-0.0500 1.2860 1.2830 0.0030 2

1.0930 1.1020

-0.0090 2

1.2060 0 8480 1.2300 0.8680

-0.0240 2

-0.0200 1.1480 1.1790

-0.0310 5

1.1080 1 09 0 1.1970 1.0970 1.2080 1.1030 1.1020 1 2p3p 1.1280 1 228p 0.0050 3

-0.0070 3

-0.0060 2

-0.0310 2q 4.0200 1

1.1040 1.1180

-0.0140 6

0.3850 1.1200 1.1860 0.3850 1 1210 1.1620 0.0000 3

-0.0010 3$

0 0240 2

1.2460 0.9780 1.2400 0.9810 0.0060 2

4.0030 1

1.2440 1.2500

.0060

~KEY 0.4230 0.4440

-0.0210 3

1.0400 p.954p 1.0270 0.9260 0.0130 2

0.0280 1.2150 1.2090 0.0060 1

0.9550 0.9940

-0.0390 8

MEASURED

DESIGN, DELTA RMS DEVIATION= ~~

0.1010 0 3310 0.1010 0 3470 0.0000 1

-0.0160 g

Page 14 of 16

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St. Lucie Unit 1, Cycle 12 TABLE 1 CYCLE 12 RELOAD SUB-BATCH ID Sub-Batch Ml M2 M3 M4 M5 Pl P2 P3 P4 P5 P6 Rl R2 R3 R4 RS

¹ ofAssemb 16 12 8

9 4

16 12 40 4

4 8

16 12 20 24 12 Enrich.

4.00 3.97 3.90 3.89 3.87 3.75 3.73 3.65 3.64 3.62 0.30 3.90 3.88 3.81 3.79 3.76 TABLE 2 APPROACH TO CRITICALITY Dilution Rate 88 gpm Init. Boron Conc.

1633 ppm Final Boron Conc.

1444 ppm DilutionTime(min) 151 1444 ppm 1377 ppm 78 Page 15 of 16

TABLE 3 COMPARISONS OF SPCND CALCULATIONS WITH MEASURED VALUES CEA Group Worth Summary CEAGrou B/5 7

2 1

4 6/3 A

Measured 509 654 699 759 824 929 1099 Desi n 570 591 674 689 714 825

'1059.2

% Diff.

11.98 %

- 9.63 %

- 3.58 %

- 9.22%

-13.35 %

-11.19 %

-3.62 %

Total 5473 5122.2

-6.41%

Note: Allworths in pcm

'%iff= (D/M-1)100 HZP Critical Boron Condition Measured Design(Adj)

Difference (M-D)

ARO 1418.7 ppm 1456 ppm

-37.3 ppm Moderator Temperature Coefficient Condition ARO Measured

+1.56 pcm/'F Design(Adj)

+1.38 pcm/'F Difference(M-D)

+0.18 pcm/'F Page 16 of 16