ML20067E440
| ML20067E440 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 01/17/1991 |
| From: | Moul D, Noonan T, Zyra T DUQUESNE LIGHT CO. |
| To: | |
| Shared Package | |
| ML20067E428 | List: |
| References | |
| NUDOCS 9102140297 | |
| Download: ML20067E440 (9) | |
Text
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DUQUIXHE LTGIT CD4PANY
- BEAVIR VALLIN PCWIR STATIOtt (UIT 2 t
CYCIZ 3 STARIUP PHYSICS TEST RLTORT Preparnd by: O //7f/ Reviewod by: Am l-lT cli D. A. Moul T.
U4 G. Zyra D yinocr II Testirq ard Plant Testirg and Plant Performance Director Performance Reviewed by: 6- I-i 7- 9i Approved by: W ! 7 7~ I/
os T. G. Zyra T. P. Noonan Technical Services General Manager Mamger Nuclear Operations 9102140297 901115 PDR P
ADOCK 05000412 PDR
BEAVfR VAILLY KUIR STATION Unit 1,ApMitMtyp.3)st Renort IlmODUCTIOtit Deaver Valley Unit 2 was shutdown on Septamter 4,1990 for its Secord Refueling Outage. During the outage, 68 of 157 fuel assemblics were replaced with a triple split batch: 20 fuel assemblics of 3.6 w/o enricitwnt,12 assemblies of 3.8 w/o enrichment and 36 fuel assemblics of 4.2 w/o enrichment. The fresh fuel rtds are based on the starrlard design with natural uranium in the top ard bottom six inches. Assemblics with Integral Fuel Burnable Absorbers (IFBA) have arrangements of 100 and 128 rods with boride-coated pellets in the central 120 inches. A region of unpoisoned fuel six inches in length is found between the natural uranium ard the boride-mated fuel in these IFBA fuel assemblics.
7his report describes the startup test program applicable for the Cycle 3 reload core design verification for BVPS, Unit 2. This testirg program corcisted of the follcwiry measurements corducted frcan llovember 15, 1990 through November 30, 1990:
- 1. Control rod drop times
- 2. Initial criticality
- 3. Baron endpoints
- 4. Control bank worths
- 5. Temperature coefficient
- 6. Roactivity ccanputer checks
- 7. 30% power symmetry check
- 8. Incore/D: core cross-calibration
- 9. Power distribution measurements at 74%, 90% and 100% reactor power
'Ihe results of these startup tests are summarized in this report and comparisons are mde to predicted design values and applicable BVPS Technical Specification Requirements.
l TINP SOEARIES:
2BVP 1.1.1 " Control Rod Droo Time Moasurements" PURPOSE:
The pur y2 of this test was to determine a drop time for each full-length Rod Control Cluster Assembly (RCCA) at Hot Standby aM full RCS flow conditions.
The test also verifies that the Digital Rod Position IMicators are within 12 steps of the group demaM counters for each control rod.
TEST DESCRIPTION:
A sirgle RCCA Bank is withdrawn to the maximum full-out position (231 steps) .
At each 24 step increment, rod position is recorded frcan the RPI control board display and the Safety Parameter Display System for comparison with the group step counter indication.
After rod withdrawal, stationary gripper coil voltage, a 120 volt 60 Hz timing trace, a M the sum of the signals from the Digital Rod Position Indication Data Cabinets A and B detector /enooder cards are connected to a multichannel visicorder. At the power control cabinets, the movable gripper aM stationary gripper fuses are renoved to initiate the rod drop. Each of the 48 rod cluster assemblics is tested in this manner aM the rod drop times are determined from the visicorder traces.
RESULTS:
The test commenced at 0107 on November 15, 1990 and was completed at 0840 hours0.00972 days <br />0.233 hours <br />0.00139 weeks <br />3.1962e-4 months <br /> on November 16, 1990. The drop times of all 48 rods were well within the BVPS Unit 2 Technical Specification Requirement of < 2.2 secoMs, with the slowest time being 1.44 socords for rod B-6 at hot full RCS ficw.
2BVP 3 2.1 " Initial Anoroach to criticality After Refuelim" l
PURPOSE:
he purpose of this test was to: (1) achieve initial criticality; (2) determine the point at which nuclear heat occurs and establich the Iow Power Physics Testing Band (LPPTB); (3) verify the proper calibration of the reactivity emputer.
TEST DESCRIFFION:
l Initial conditions were established on November 20, 1990 at 0326 with the '
following corditions: shutdown banks fully withdrawn, control banks fully inserted, boron concentration at 2101 ppm, RCS tenperature at 547 F, and RCS pressure at 2262 psig.
he control banks were withdrawn in 50 step intervals until Control Bank D reached 160 steps. Luring control rod withdrawal, the Inverse Count Rate Ratio (ICRR) was monitored at 50 step increments and decreased frm 1.0 to 0.43.
We ICRR was renormalized to 1.0 and dilution to criticality s' h at 0400 at a rate of 46 gpn (51000 pcm/hr) . During the dilution, ICRR data was obtained at 20 minute intervals ard plotted versus boron concentration and makeup water added. At 1120, on November 20,1990 after 14,000 gallons of primary makeup water had been injected, criticality was achieved.
Following the recording of critica.lity data, flux was increased towards nuclear heat. Nuclear heating was observed at 6.9 x 10-7 amps on the reactivity cx2nputer.
A reactivity cmputer calibration check was then performed using the reactor with positive reactivity insertions of 24 pcm, 32 pcm, and 59 pcm. Se doubling times were measured and predicted reactivity cmpared to measured for each insertion.
2BVI 2.2.1 was ccxtpleted at 1555 on November 20, 1990.
RLSULTS:
.So All Rods Out (ARO) critical boron cancentration corrected for red position was calculated to be 1670 ppu which was within the acceptance criteria of 1671 1 50 ppm.
he IPPTB was set at 2.5 x 10-9 amps to 3 x 10-8 amps based on an observed nuclear heating point of 6.9 x 10-7 amps and a backgrourd current reading of 2.5 x 10 -10 amps for power range detector N44.
he measured errors for the reactivity cmputer calibration check were 0.31%,
-0.84%, ard 1.26%, which was within the acceptance criteria of i 4%.
- 2BVP 2.2.2 " Core Desian Check 7bst" PURPOSE:
The purpose of this test was to verify the reactor core design frca hot zero power to 100 percent reactor power, and to perform the initial incore/excore cross-calibration.
TESP der 4RIPPION:
The test was divided into five parts:
Section- A covered Iow Power Physics 7bsting. These tests are performed in the low Power Physics Testing Band at less than 5% reactor power. They include the following measurements: boron endpoints, boron dilution worth measurement of the reference bank (CBB), rod swap bank worths, differential baron worth, and an isothermal temperature coefficient measurement.
Section .B involved- performing a full-core flux map prior to exceeding 30%
reactor power to verify core symetry and proper core loading.
Section C required a full-core flux map to be obtained between 40% and 75%
reactor power to ensure the measured peaking factors were within their applicable Technical Specification Limits.
Section D required that an incore/excore calibration be performed between 50%
and 100% reactor power. This imelved perfonning 2BVT 2.2.3, " Nuclear power Range Calibration", in which a series of flux maps are performed at various axial offsets.
Finally, Section E involved performing a full-core flux map at 100% reactor power. This map served as a calibration check for the incore/excore calibration 'and' verified that the power distribution limits of the Technical Specifications were not e W .
RESULTS:
Boron Endnoints:.
The All Rods Out (ARO) critical boron concentration was measured to be 1648 ppu which was within the acceptance criteria of 1671 1 50 ppn.
The Control Bank B-in critical boron concentration was measured to be 1488 ppn which was within the acceptance criteria of 1497 ppm i 15% (1272.4 ppu to 1721.6 ppn)~._ _
-. . _.---_--_---a- -. a._._--.-__--.--- - .. a
l ATrcrature Coefficier)t:
.20 ATO, HZP Isotherml Temperature Coefficient (I'IC) was determired to be
-2.12 pcm/F khich was within the acceptance criteria of -2.9513 pam/F.
Subtractirg out the predicts.d design value of the Doppler Coefficient (-1.66 pcm/F) frun the reasured ITC, the infcrred Itdcrator 7bnporature Cbefficiont (MIC) was calculated to be -0.46 pam/F. 2his value rects the requircments of the DVPS Unit 2 7bchnical Specifications which rcquires the MIC to be betwoon
-50 pcm/F ard 0 pcm/F. The station has in place procedures to ensure that a ncgative MIC is mintainod thrcughout cycle 3 core life.
Diffcrential Boron Worth:
We reasured differential boron worth was 7.80 pczn/ppn khich was within the acceptance criteria of 7.66 pcm/ppn 15% (6.51 pcm/ppu to 8.81 pcm/ppn) .
RCC Bank Worths:
We boron dilution rethcd of rod worth measurement was used to deters worth of the reference bank (Control Bank B) for rod swap. The wort reminiry control and shutdown banks were obtainod relative to measured worth, predicted value, ard percent difference for each 10 total RCC worth are licttd in Table 1. All the reasured values were viu 9 aca ptance criteria for this test.
Reactivity Comruter:
The reactivity emputer calibration was chocked prior to Irw Power Ih,_ 1 Tcstirg (LPPT) and every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> durirg the test usirg the exponentiaA generator. In addition, an operational calibratior, check usirq the reactor was also perfonned follcwirg initial criticality. In all casos the camput~ error was within the 4% acceptance criteria, with the highest reasured err, - tcirg 2.36%.
30 Percent Pcuer Symmetry Chock:
A full-core flux map was performed on November 24, 1990 at approxim tely 30%
reactor power with Control Bank D at 183 steps to determine the initial flux distribution in the core. Table 2 lists the values for quadrant tilt and mxiraum deviation frcan predicted assembly powers for the 30% flux mp. All measured values were within the acceptance criteria for the test.
74 Peregnt Pcwer Flux Map mid Incore/Excore Calibration:
On November 26 and 27,1990 2BVP 2.2.3, " Nuclear Pcuer Range Calibration" was performed at approximtcly 74% reactor power. This test involved a full-core ard six quarter-core flux mps obtained at various axial offrets to calibrate the excore detectors and verify core peakirg factors. W e results of the full-core flux rap are shom in Table 2.
All measured values were within the acceptance criteria. W e measured Pxy corrected for uncertainties was 1.7355 for the 74% flux mp. Technical Specifications require this value to be less than Fxy(RTP) (1.65) ard Fxy(LIM)
(1.7760 for 74% power). The measured Fxy was less than Fxy(LIM), however it excecded Fxy(RTP) . This rcquired an additional pcuer distribution check to be done at 90% power per Technical Specification 4.2.2.2.d.1.
90 Prrcuit Power F1w mad:
On llovember 28, 1990 a full-core flux map was performed at 90% reactor powcr.
This map was performed to satisfy 7bchnical Specification 4.2.2.2.d.1 surveillance requiruments due to the measured hy eMirg Fxy(RTP) frcan aralysis of the 74% power flux map. The results of the full-core flux map are shown in Table 2. All measured values were within the acceptance criteria.
The masured by corrected for unocrtainties was 1.7062. Techni al Specificatic.a require this value to be less th:n hy(RTP) (1.69) and hy(IDf)
(1.7276 for 90% power) . Orce again, hy was less th a hy(LIM), hcwever it was greater than Fxy(RTP). The full-core flux map at 100 percent power would be uscd to satisfy surveillance requirements of 7bchnical Specification 4.2.2.2.d.1.
100 Pccx5it Pcwer Flux Man On 14cvenbcr 30, 1990 a full-core flux map was performed at 100% reactor power.
This map .W as a che::k for the in: ore /excore calibration and power distribution limits. The results of the map are shcun in Table 2. The ircoro/exoore calibration performed at 74% power was satisfactory. Analysis of the p3wer distribution limits shcwod that Fxy ELM 3 its surveillance limit (hy 2 Pxy(LIM)) by approximately 0.5% at axial point 45.
Westirghouse was notified of the hy masurement ard was requested to analyze the mrgin to 19 limit. Westinghouse's analysis showed that in the ragion curroundirg axial point 45, a 4 to 5 percent mrgin to 14 lir.it existed.
Westirghouse provided written notification that Unit 2 could take credit for this mrgin ard could justify continued full pswer operation of cycle 3.
'Ibe 100% flux map marked the ocarpletion of the reload startup test svpam for Beaver Valley Power Station Unit 2, cycle 3.
TABIE 1 ODITIlOL IOD BANK WORIHS Measured Predicted Worth Worth Error Acceptance llaDh (Dem) (ocm) (%) Criteria CCB* 1286.50 1330 -3.27 10%
CBD 941.25 1003 -6.16 i 15%
CBC 733.44 802 -8.55 i 15%
CBA 628.34 664 -5.37 1 15%
SBB 882.98 973 -9.25 i 15%
SBA 1072.78 1106 -3.00 15%
'Ibtal Worth 5545.29 5878 -5.66 1 15%
- Reference Bank for Rod Swap.
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i FUIL CORE FUJX MAP SLRNARY .;
1 30% Power 74% Power 90% Power 100% Power CSD. CBD' GD . CBD Acceptance Parameters 161 steps 219 steps 225. steps 228 s4s;!g critaria Quadrant 1.0095 1.0168 1.0106 1.0106 s 1.02 for power i Tilt above 50%
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Maxinum 6.4% 7.6% 6.6% 6.9%. - 1 10% for a Deviation. Predicted -*
fran Predicted Relative Power q, . Assembly, Powers > .9 T,p F delta H- N/A 1.5446 1.5187 1.5248 h t. Spec.:..
< 1.6681.for 74%
< 1.6017 for 90%
. < 1.5560 for 100% ,
- 9. .
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Fxy N/A -1.7355 1.7062 .1.7028 Tech. Spec.:
-< 1.7760 for 74% l
=< 1.7276.for 90% .<
<-1.6943 for 100% f.,;
Fxy(RIP) = 1.69 j 1
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