L-20-036, of the Unit Cycle 2 Cycle 3 Core Operating Limits Report (COLR)
ML20211L689 | |
Person / Time | |
---|---|
Site: | Watts Bar ![]() |
Issue date: | 07/29/2020 |
From: | Anthony Williams Tennessee Valley Authority |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
WBL-20-036 | |
Download: ML20211L689 (13) | |
Text
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Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 WBL-20-036 July 29, 2020 10 CFR 50.4 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 Facility Operating License No. NPF-96 NRC Docket No. 50-391
Subject:
REVISION 1 OF THE UNIT 2 CYCLE 3 CORE OPERATING LIMITS REPORT (COLR}
Pursuant to Watts Bar Nuclear Plant Technical Specifications Section 5.9.5.d, Tennessee Valley Authority (TVA) has enclosed Revision 1 of the Unit 2 Cycle 3 COLR. The analytical methods used to determine the core operating limits were previously reviewed and approved by the NRC.
There are no regulatory commitments contained in this letter or the enclosure.
Should you have questions regarding this submittal, please contact Tony Brown at (423) 365-7720.
Anthony L. Williams IV Site Vice President Watts Bar Nuclear Plant
Enclosure:
Watts Bar Nuclear Plant, Unit 2, Cycle 3 Core Operating Limits Report Revision 1 July 2020
U.S. Nuclear Regulatory Commission Page 2 WBL-20-036 July 29, 2020 cc (Enclosure):
NRC Regional Administrator - Region II NRR Project Manager - Watts Bar Nuclear Plant NRC Senior Resident Inspector - Watts Bar Nuclear Plant
ENCLOSURE Watts Bar Nuclear Plant, Unit 2, Cycle 3 Core Operating Limits Report Revision 1 July 2020
QA Record L36 200714 802 WATTS BAR NUCLEAR PLANT, UNIT Z CYCLE 3 CORE OPERATING LIMITS REPORT Revision I July 2020 Prepared by:
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Kome L Yetzer, PWR Pu Engineering Date VeriIed by:
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I Jamel C. Bell, PWR Fuel I ngineering Date Reviewed by:
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John A. Ritchie, Manager, WR Fuel Engineering Date signed by Mack, Bryan Thomas IviaCrI, I,
urya ri .omas Digitally Date:2O2O.O7.16O951O5-O4'OO' Bryan T. Mack, Manager, eactor Engineering Date
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ate PORC Chairman
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I Plant Manager (late Date of POR Affected Revision Approval -
Pages Reason for Revision 0 04/09/2019 All Initlalissue Revised Table A.1 for W(z) Error as I See Above documented in CR 1620559.
Unit2 Cycle 3 WAITS BAR Page 1 of 10 Revision I
1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Watts Bar Unit 2 Cycle 3 has been prepared in accordance with the requirements of the Technical Specifications (TS) 5.9.5.
The Technical Specifications affected by this report are listed below:
3.1.4 Moderator Temperature Coefficient (MTC) 3.1.5 Rod Group Alignment Limits 3.1.6 Shutdown Bank Insertion Limits 3.1.7 Control Bank Insertion Limits 3.2.1 Heat Flux Hot Channel Factor (FQ(Z))
3.2.2 Nuclear Enthalpy Rise Hot Channel Factor (FHN) 3.2.3 Axial Flux Difference (AFD) 3.9.1 Boron Concentration 2.0 OPERATING LIMITS The cycle-specific parameter limits for the specifications listed in section 1.0 are presented in the following subsections. These limits have been developed using the NRC approved methodologies specified in the Technical Specifications Section 5.9.5.
The following abbreviations are used in this section:
BOL -- Beginning of Cycle Life ARO -- All Rods Out HZP -- Hot Zero Thermal Power EOL -- End of Cycle Life RTP -- Rated Thermal Power Unit 2 Cycle 3 WATTS BAR Page 2 of 10 Revision 1
2.1 MODERATOR TEMPERATURE COEFFICIENT - MTC (LCO 3.1.4) 2.1.1 The MTC limits are:
The ARO/HZP - MTC shall be less positive than or equal to 0 k/k/°F (upper limit).
With the measured BOL/ARO/HZP - MTC more positive than -1.93 x 10-5 k/k/°F (as-measured MTC limit), establish control rod withdrawal limits to ensure the MTC remains less positive than or equal to 0 k/k/°F (upper limit) for all times in core life.
The EOL/ARO/RTP - MTC shall be less negative than or equal to
-4.50 x 10-4 k/k/°F (lower limit).
2.1.2 The 300 ppm surveillance limit is:
The measured 300 ppm /ARO/RTP-MTC should be less negative than or equal to
-3.75 x 10-4 k/k/°F.
2.1.3 The 60 ppm surveillance limit is:
The measured 60 ppm /ARO/RTP-MTC should be less negative than or equal to
-4.28 x 10-4 k/k/°F.
2.2 SHUTDOWN MARGIN - SDM (LCO 3.1.5, 3.1.6, 3.1.7) 2.2.1 For TS 3.1.5, SDM shall be 1.6% k/k in MODE 1 and MODE 2.
2.2.2 For TS 3.1.6, SDM shall be 1.6% k/k in MODE 1 and MODE 2.
2.2.3 For TS 3.1.7, SDM shall be 1.6% k/k in MODE 1 and MODE 2 with keff 1.0.
2.3 SHUTDOWN BANK INSERTION LIMITS (LCO 3.1.6) 2.3.1 The shutdown banks shall be withdrawn to a position greater than or equal to 225 steps withdrawn.
2.4 CONTROL BANK INSERTION LIMITS (LCO 3.1.7) 2.4.1 The control banks are fully withdrawn or shall be limited in physical insertion as shown in Figure 1.
2.4.2 Each control bank shall be considered fully withdrawn from the core at greater than or equal to 225 steps.
2.4.3 The control banks shall be operated in sequence by withdrawal of Bank A, Bank B, Bank C, and Bank D. The control banks shall be sequenced in reverse order upon insertion.
Unit 2 Cycle 3 WATTS BAR Page 3 of 10 Revision 1
2.4.4 Each control bank not fully withdrawn from the core shall be operated with the following overlap as a function of park position.
Park Position (steps) Bank Overlap (steps) Bank Difference (steps) 225 109 116 226 110 116 227 111 116 228 112 116 229 113 116 230 114 116 231 115 116 2.5 HEAT FLUX HOT CHANNEL FACTOR - FQ(Z) (LCO 3.2.1)
FQ(Z) [CFQ / P]
- K(Z) for P > 0.5 FQ(Z) [CFQ / 0.5]
- K(Z) for P 0.5 Where P = Thermal Power / Rated Thermal Power 2.5.1 CFQ = 2.50 2.5.2 K(Z) is provided in Figure 2.
2.5.3 FQW(Z) = FQc(Z)
- W(Z)/P for P > 0.5 FQW(Z) = FQc(Z)
- W(Z)/0.5 for P 0.5 where: W(Z) values are provided in Table A.1. The table provides sufficient information to determine W(Z) versus core height for all cycle burnups.
2.5.4 Part power W(Z) values are only required to be used when the part power surveillance is performed using the fixed incore detector system.
2.5.5 FQW(Z) Penalty Factor The FQW(Z) penalty factor is provided in Table A.2.
Unit 2 Cycle 3 WATTS BAR Page 4 of 10 Revision 1
2.6 NUCLEAR ENTHALPY RISE HOT CHANNEL FACTOR - FHN (LCO 3.2.2)
FHN FHRTP * ( 1 + PF * ( 1-P))
where P = Thermal Power / Rated Thermal Power FHRTP = 1.65 for RFA-2 fuel, and PF = 0.3 2.7 AXIAL FLUX DIFFERENCE - AFD (LCO 3.2.3) 2.7.1 The AFD limits for Cycle 3 are provided in Figure 3.
2.8 REFUELING BORON CONCENTRATION (LCO 3.9.1) 2.8.1 The refueling boron concentration shall be 2000 ppm.
Unit 2 Cycle 3 WATTS BAR Page 5 of 10 Revision 1
250 BANK A (ALL POWERS, 225) 225 (0.197, 225) (0.703, 225) 200 BANK B (1.0, 177)
ROD BANK STEP POSITION (STEPS WITHDRAWN) 175 (0.0, 180) 150 BANK C 125 100 BANK D 75 (0.0, 64) 50 25 (0.227, 0) 0 0.0 0.2 0.4 0.6 0.8 1.0 FRACTION OF RATED THERMAL POWER Figure 1 Control Bank Insertion Limits Versus Thermal Power Four Loop Operation Note: Fully withdrawn region shall be the condition where shutdown and control banks are at a position within the interval of 225 and 231 steps withdrawn.
Unit 2 Cycle 3 WATTS BAR Page 6 of 10 Revision 1
1.2 1.1 1
0.9 0.8 Normalized FQ
- Power 0.7 0.6 Core Height K(Z) 0.000 1.000 6.000 1.000 0.5 12.000 1.000 0.4 0.3 0.2 0.1 0
0 1 2 3 4 5 6 7 8 9 10 11 12 Core Height (feet)
Figure 2 K(Z) - Normalized FQ(Z) as a Function of Core Height Unit 2 Cycle 3 WATTS BAR Page 7 of 10 Revision 1
120 110
(-12, 100) (7, 100) 100 90 Acceptable Operation 80 Unacceptable Unacceptable Operation Operation
% of Rated Thermal Power 70 60 50
(-28, 50) (21, 50) 40 30 20 10 Figure 3 Axial Flux Difference Acceptable Operation Limits as a Function of Rated Thermal Power (RAOC) 0
-50 -40 -30 -20 -10 0 10 20 30 40 50 Flux Difference (I) %
Figure 3 Axial Flux Difference Acceptable Operation Limits as a function of Rated Thermal Power (RAOC)
Unit 2 Cycle 3 WATTS BAR Page 8 of 10 Revision 1
Table A.1 RAOC W(Z) Surveillance Factors Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) at 150 at 150 at 150 at 2000 at 4000 at 8000 at 12000 at 16000 Height (ft) MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU (30% (75% (100% (100% (100% (100% (100% (100%
Power) Power) Power) Power) Power) Power) Power) Power) 12.0720 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.8708 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.6696 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.4684 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.2672 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.0660 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 10.8648 1.2497 1.2760 1.1798 1.2132 1.2089 1.2179 1.2045 1.1797 10.6636 1.2412 1.2601 1.1760 1.2059 1.1985 1.2049 1.1918 1.1764 10.4624 1.2347 1.2468 1.1714 1.2051 1.1954 1.1994 1.1768 1.1720 10.2612 1.2285 1.2330 1.1704 1.2012 1.1902 1.1921 1.1693 1.1668 10.0600 1.2224 1.2224 1.1719 1.1949 1.1957 1.1847 1.1659 1.1635 9.8588 1.2131 1.2072 1.1743 1.1878 1.1927 1.1839 1.1616 1.1610 9.6576 1.1971 1.1907 1.1748 1.1801 1.1863 1.1815 1.1567 1.1577 9.4564 1.1773 1.1718 1.1726 1.1723 1.1916 1.1770 1.1509 1.1537 9.2552 1.1564 1.1557 1.1680 1.1751 1.1880 1.1748 1.1506 1.1510 9.0540 1.1378 1.1424 1.1659 1.1781 1.1833 1.1766 1.1541 1.1585 8.8528 1.1293 1.1400 1.1820 1.1782 1.1810 1.1763 1.1565 1.1723 8.6516 1.1265 1.1469 1.1986 1.1806 1.1846 1.1816 1.1631 1.1910 8.4504 1.1221 1.1506 1.2138 1.1875 1.1895 1.1952 1.1800 1.2108 8.2492 1.1242 1.1620 1.2257 1.1917 1.1922 1.2047 1.1943 1.2292 8.0480 1.1150 1.1633 1.2350 1.1938 1.1929 1.2120 1.2063 1.2450 7.8468 1.1085 1.1668 1.2418 1.1941 1.1920 1.2171 1.2160 1.2582 7.6456 1.1035 1.1687 1.2445 1.1914 1.1883 1.2190 1.2227 1.2679 7.4444 1.0910 1.1680 1.2449 1.1866 1.1832 1.2191 1.2275 1.2756 7.2432 1.0882 1.1664 1.2428 1.1836 1.1775 1.2164 1.2292 1.2794 7.0420 1.0843 1.1643 1.2388 1.1828 1.1721 1.2118 1.2288 1.2803 6.8408 1.0786 1.1606 1.2331 1.1804 1.1692 1.2056 1.2264 1.2788 6.6396 1.0681 1.1537 1.2247 1.1762 1.1650 1.1978 1.2220 1.2745 6.4384 1.0595 1.1477 1.2152 1.1711 1.1599 1.1887 1.2163 1.2678 6.2372 1.0570 1.1403 1.2046 1.1650 1.1538 1.1783 1.2088 1.2587 6.0360 1.0520 1.1324 1.1924 1.1590 1.1496 1.1665 1.1997 1.2475 5.8348 1.0401 1.1212 1.1776 1.1546 1.1459 1.1535 1.1890 1.2342 5.6336 1.0443 1.1184 1.1716 1.1499 1.1416 1.1426 1.1768 1.2189 5.4324 1.0440 1.1191 1.1674 1.1474 1.1392 1.1403 1.1626 1.2009 5.2312 1.0486 1.1201 1.1647 1.1479 1.1392 1.1396 1.1566 1.1939 5.0300 1.0513 1.1200 1.1633 1.1510 1.1398 1.1396 1.1569 1.1939 4.8288 1.0597 1.1248 1.1633 1.1528 1.1403 1.1388 1.1557 1.1920 4.6276 1.0688 1.1288 1.1640 1.1542 1.1422 1.1374 1.1541 1.1891 4.4264 1.0757 1.1333 1.1638 1.1549 1.1434 1.1369 1.1515 1.1850 4.2252 1.0831 1.1362 1.1626 1.1547 1.1440 1.1379 1.1484 1.1798 4.0240 1.0941 1.1384 1.1605 1.1537 1.1439 1.1380 1.1443 1.1737 3.8228 1.1039 1.1411 1.1580 1.1523 1.1433 1.1385 1.1451 1.1662 3.6216 1.1082 1.1400 1.1552 1.1507 1.1424 1.1403 1.1493 1.1569 3.4204 1.1161 1.1414 1.1522 1.1482 1.1414 1.1436 1.1521 1.1529 3.2192 1.1329 1.1487 1.1531 1.1480 1.1404 1.1480 1.1547 1.1517 3.0180 1.1519 1.1608 1.1615 1.1535 1.1517 1.1529 1.1567 1.1530 2.8168 1.1852 1.1836 1.1798 1.1725 1.1751 1.1691 1.1687 1.1661 2.6156 1.2186 1.2098 1.2019 1.1980 1.1977 1.1919 1.1868 1.1845 2.4144 1.2563 1.2361 1.2230 1.2219 1.2209 1.2133 1.2034 1.2016 2.2132 1.2955 1.2653 1.2442 1.2465 1.2443 1.2352 1.2204 1.2191 2.0120 1.3369 1.2925 1.2656 1.2712 1.2680 1.2568 1.2367 1.2354 1.8108 1.3721 1.3189 1.2865 1.2953 1.2913 1.2776 1.2519 1.2504 1.6096 1.4092 1.3435 1.3058 1.3177 1.3129 1.2969 1.2659 1.2645 1.4084 1.4617 1.3714 1.3233 1.3380 1.3327 1.3145 1.2791 1.2779 1.2072 1.4983 1.3930 1.3393 1.3564 1.3507 1.3305 1.2911 1.2905 1.0060 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.8048 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.6036 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.4024 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.2012 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Unit 2 Cycle 3 WATTS BAR Page 9 of 10 Revision 1
Table A.2 FQW(Z) Penalty Factor Burnup Penalty (MWD/MTU) Factor 448 1.0200 597 1.0205 746 1.0221 895 1.0235 1043 1.0227 1192 1.0200 Note:
- 1. The Penalty Factor, which is applied to FQW(Z) for compliance with Surveillance Requirement 3.2.1.2, is the maximum factor by which FQW(Z) is expected to increase per 31 Effective Full Power Days (EFPD) starting from the burnup at which the FQW(Z) was determined.
Unit 2 Cycle 3 WATTS BAR Page 10 of 10 Revision 1