BW250046, Core Operating Limits Report (COLR) for Braidwood Unit 1 Cycle 26, Revision 22
| ML25295A004 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 10/22/2025 |
| From: | Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML25295A002 | List: |
| References | |
| BW250046 | |
| Download: ML25295A004 (1) | |
Text
CORE OPERATING LIMITS REPORT (COLR)
FOR BRAIDWOOD UNIT 1 CYCLE 26 CONSTELLATION TRACKING ID:
COLR BRAIDWOOD 1 REVISION 22
COLR BRAIDWOOD I Revision 22 Page I of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Braidwood Station Unit 1 Cycle 26 has been prepared in accordance with the requirements of Technical Specification 5.6.5 (ITS).
The Technical Specification Safety Limits and Limiting Conditions for Operation (LCOs) affected by this report are listed below:
SL 2.1.1 LCO 3.1.1 LCO 3.1.3 LCO 3.1.4 LCO 3.1.5 LCO 3.1.6 LCO 3.1.8 LCO 3.2.1 LCO 3.2.2 LCO 3.2.3 LCO 3.3.1 LCO 3.3.9 LCO 3.4.1 Reactor Core Safety Limits (SLs)
SHUTDOWN MARGIN (SOM)
Moderator Temperature Coefficient (MTC)
Rod Group Alignment Limits Shutdown Bank Insertion Limits Control Bank Insertion Limits PHYSICS TESTS Exceptions-MODE 2 Heat Flux Hot Channel Factor (Fo(Z))
Nuclear Enthalpy Rise Hot Channel Factor (FN11H)
AXIAL FLUX DIFFERENCE (AFD)
Reactor Trip System (RTS) Instrumentation Boron Dilution Protection System (BOPS)
Reactor Coolant System (RCS) Pressure, Temperature, and Flow Departure from Nucleate Boiling (DNB) Limits LCO 3.9.1 Boron Concentration The portions of the Technical Requirements Manual (TRM) affected by this report are listed below:
TRM TLCO 3.1.b TRM TLCO 3.1.f TRM TLCO 3.1.g TRM TLCO 3.1.h TRM TLCO 3.1.i TRM TLCO 3.1.j TRM TLCO 3.1.k Boration Flow Paths - Operating Borated Water Sources - Operating Position Indication System - Shutdown Shutdown Margin (SOM) - MODE 1 and MODE 2 with keff ~ 1.0 Shutdown Margin (SOM) - MODE 5 Shutdown and Control Rods Position Indication System - Shutdown (Special Test Exception)
COLR BRAIDWOOD I Revision 22 Page 2 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT l CYCLE 26 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 are applicable for the entire cycle unless otherwise identified. These limits have been developed using the NRG-approved methodologies specified in Technical Specification 5.6.5.
2.1 Reactor Core Safety Limits (SLs) (SL 2.1.1) 2.1.1 In MODES 1 and 2, the combination of Thermal Power, Reactor Coolant System (RCS) highest loop average temperature, and pressurizer pressure shall not exceed the limits specified in Figure 2.1.1.
r11r: -.---------,------,--------r-------,.------,-------,
2-1' 71 psia 2250 psia
- _\\-'1 Fruc:ion of o.o 1\\lcn*iriul F'c**iicr Figure 2.1.1: Reactor Core Limits 1.**,,
- L
2.2 2.3 COLR BRAIDWOOD 1 Revision 22 Page 3 of 12 CORE OPERA TING LIMITS REPORT (COLR) for BRAIDWOOD UNIT 1 CYCLE 26 SHUTDOWN MARGIN {SOM)
The SOM limit for MODES 1, 2, 3, and 4 is:
2.2.1 The SOM shall be greater than or equal to 1.3% Ak/k (LCOs 3.1.1, 3.1.4, 3.1.5, 3.1.6, 3.1.8, 3.3.9; TRM TLCOs 3.1.b, 31.f, 3.1.h, and 3.1.j).
The SOM limit for MODE 5 is:
2.2.2 SOM shall be greater than or equal to 1.3% Ak/k (LCO 3.1.1, LCO 3.3.9; TRM TLCOs 3.1.i and 3.1.j).
Moderator Temperature Coefficient {MTC) (LCO 3.1.3)
The Moderator Temperature Coefficient (MTC) limits are:
2.3.1 The BOL/ARO/HZP-MTC upper limit shall be +6.44 x 10-5 Ak/k/°F.
2.3.2 The EOL/ARO/HFP-MTC lower limit shall be -4.6 x 10-4 Ak/k/°F.
2.3.3 The EOL/ARO/HFP-MTC Surveillance limit at 300 ppm shall be -3.7 x 10-4 Ak/k/°F.
2.3.4 The EOL/ARO/HFP-MTC Surveillance limit at 60 ppm shall be -4.3 x 10-4 Ak/k/°F.
where: BOL stands for Beginning of Cycle Life ARO stands for All Rods Out HZP stands for Hot Zero Thermal Power EOL stands for End of Cycle Life HFP stands for Hot Full Thermal Power 2.4 Shutdown Bank Insertion Limits (LCO 3.1.5) 2.4.1 All shutdown banks shall be fully withdrawn to at least 225 steps.
2.5 Control Bank Insertion Limits (LCO 3.1.6) 2.5.1 The control banks, with Bank A greater than or equal to 225 steps, shall be limited in physical insertion as shown in Figure 2.5.1.
2.5.2 Each control bank shall be considered fully withdrawn from the core at greater than or equal to 225 steps.
2.5.3 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.
2.5.4 Each control bank not fully withdrawn from the core shall be operated with the following overlap limits as a function of park position:
Park Position (step)
Overlap Limit (step) 231 115
COLR BRAIDWOOD 1 Revision 22 Page 4 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 225 220 200 180 Figure 2.5.1:
Control Bank Insertion Limits Versus Percent Rated Thermal Power
/
{26.95%, 225)
V
~ANKB I
~
- /1 i
~
/
{77.39%, 225)
~
/ V
/
160 c
==
l!! 140 j(D%, 163)
I L
/
{100%, 161)
"C
.c 3
cS. 120 a,
~
C:
0 100
/
I BANK C I
/
/
0
- 0.
~
C:
80 ra
/
V
/
a:i "C
0 a::
60 40 20 0
/ /
V
/
/
/
r1 (0%, 47) I
/
~/
1(30%,0) V 0
10 20 30 40 50 60 Rated Thermal Power (Percent)
The bank position is given as follows:
Control Bank D: (161/70) * (P-100) + 161 (for 30 SP S 100)
Where P is defined as the core power (in percent).
70
/~
/
V
!BANK D I 80 90 100
2.6 COLR BRAIDWOOD I Revision 22 Page 5 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 Heat Flux Hot Channel Factor (Fo(Z)) (LCO 3.2.1) 2.6.1 Total Peaking Factor:
F.RTP FQ(Z) :5 7 x K(Z) for P > 0.5 where: P = the ratio ofTHERMAL POWER to RATED THERMAL POWER K(Z) is provided in Figure 2.6.1.
Figure 2.6.1 K(Z) - Normalized FQ(Z) as a Function of Core Height (0.0, 1.0)
(6.0, 1.0)
(12.0,1.0) 1.1 1
0.9 '
0.8 0.7 '
N' a... 0.6 '
"'C CII iii E 0.5 '
0 z
~ 0.4 I
..... LOCA Limiting L___ Envelope 0.3 0.2 0.1 0
0 1
2 3
4 5
6 7
8 9
10 11 12 BOTTOM Core Height (ft)
COLR BRAIDWOOD I Revision 22 Page 6 of 12 CORE OPERA TING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 2.6.2 V(Z) Values:
V(Z) values are provided in Table 2.6.2.a and correspond to the AXIAL FLUX DIFFERENCE (AFD) Acceptable Operation Limits provided in Figure 2.8.1.
Table 2.6.2.b shows the Foc(z) penalty factors that are greater than 2% per the allowable surveillance frequency. These values shall be used to increase the Fov(Z) as per Surveillance Requirement 3.2.1.2. A 2% penalty factor shall be used at all cycle burnups that are outside the range of Table 2.6.2.b.
Per Technical Specification 3.2.1, Action B.1, for the X% in which FoV(Z) exceeds the limit, multiply X% by the following factor to determine the reduction in the positive and negative AFD limits:
%AFD/%FQ = 1.2
2.6.3 Uncertainty
The uncertainty, UFo, to be applied to the Heat Flux Hot Channel Factor Fo(Z) shall be calculated by the following formula where:
Uqu = Base Fo measurement uncertainty= 1.05 Ue = Engineering uncertainty factor= 1.03
COLR BRAIDWOOD 1 Revision 22 Page 7 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT 1 CYCLE 26 Table 2.6.2.a V(Z) versus Core Height for Normal AFD Acceptable Operation Limits in Figure 2.8.1 (Top and Bottom 8% Excluded per Braidwood SR 3.2.1.2 Bases)
Height 150-5500 3500 -9500 7500 - 16500 (feet)
MWD/MTU MWD/MTU MWD/MTU 0.25 (core bottom) 1.2651 1.2422 1.2839 0.75 1.2579 1.2383 1.2766 1.25 1.2488 1.2299 1.2627 1.75 1.2326 1.2164 1.2418 2.25 1.2126 1.1982 1.2143 2.75 1.1883 1.1765 1.1895 3.25 1.1604 1.1549 1.1623 3.75 1.1491 1.1437 1.1553 4.25 1.1385 1.1321 1.1450 4.75 1.1265 1.1171 1.1311 5.25 1.1102 1.0999 1.1304 5.75 1.1045 1 0916 1.1263 6.25 1.1097 1.0947 1.1367 6.75 1.1391 1.1159 1.1628 7.25 1.1638 1.1408 1.1823 7.75 1.1825 1.1620 1.1941 8.25 1.1961 1.1794 1.1986 8.75 1.2009 1.1978 1.2143 9.25 1.2068 1.2118 1.2253 9.75 1.2139 1.2212 1.2325 10.25 1.2196 1.2268 1.2365 10.75 1.2225 1.2289 1.2379 11.25 1.2242 1.2267 1.2335 11.75 (core top) 1.2177 1.2207 1.2280 Table 2.6.2.b Penalty Factors in Excess of 2%
Cycle Burnup Penalty Factor (MWD/MTU)
Foc(zf 0to23,326 1.02
- For Braidwood Unit 1 Cycle 26 there are no values above 1.02 Table 2.6.2.b Notes:
14500 - EOC MWD/MTU 1.3034 1.2896 1.2722 1.2485 1.2182 1.1895 1.1623 1.1583 1.1509 1.1701 1.1796 1.1770 1.1751 1.1824 1.1912 1.2046 1.2120 1.2132 1.2103 1.2301 1.2451 1.2519 1.2449 1.2201 All cycle burn ups outside the range of Table 2.6.2.b shall use a 2% penalty factor for compliance with the 3.2.1.2 Surveillance Requirements.
2.7 COLR BRAIDWOOD I Revision 22 Page 8 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 Nuclear Enthalpy Rise Hot Channel Factor (FNi1H) (LCO 3.2.2) 2.7.1 FNi1H:,; FfJP [1.0 + PFi1H(1.0 - P))
where: P = the ratio of THERMAL POWER to RATED THERMAL POWER (RTP)
FfJP = 1.70 for Framatome fuel FfJP = 1.615 for Westinghouse fuel PFi1H = 0.3
2.7.2 Uncertainty
The uncertainty, UFi1H, to be applied to the Nuclear Enthalpy Rise Hot Channel Factor FNi1H shall be calculated by the following formula:
Uri1H = Uri1Hm where:
UFLJHm = Base FNi1H measurement uncertainty= 1.04 2.8 AXIAL FLUX DIFFERENCE (AFD) (LCO 3.2.3) 2.9 2.8.1 The AXIAL FLUX DIFFERENCE (AFD) Acceptable Operation Limits are provided in the Figures described below.
a)
Figure 2.8.1 is the Normal AFD Acceptable Operation Limits associated with the V(z) values in Table 2.6.2.a. These limits may be modified in accordance with the instructions in Section 2.6.2 if LCO 3.2.1 Required Action B.1 must be taken.
DELETED
COLR BRAIDWOOD l Revision 22 Page 9 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT l CYCLE 26 Figure 2.8.1:
120 100 a::
w 3:
0 0..
80
<C
~
0:::
w 60 J:
I-C w
~ 40 a:: -
0 20 0
-50 Normal Axial Flux Difference Limits as a Function of Rated Thermal Power Normal Axial Flux Difference Limits Una:cceptab!e O~erationf 1 (-10, 100) 1 1 (+10, 100) 1
~cceptable Oper:ation Uoaccept~ble
- Operatrd,n *
(-20, 50) 1 (+25, 50) 1
-40
-30
-20
-10 0
10 20 30 40 AXIAL FLUX DIFFERENCE(%)
50
COLR BRAIDWOOD 1 Revision 22 Page 10 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 2.10 Reactor Trip System (RTS) Instrumentation (LCO 3.3.1) - Overtemperature ~ T Setpoint Parameter Values 2.10.1 2.10.2 2.10.3 2.10.4 2.10.5 2.10.6 2.10.7 2.10.8 The Overtemperature ~ T reactor trip setpoint K1 shall be equal to 1.325.
The Overtemperature ~ T reactor trip setpoint Tavg coefficient K2 shall be equal to 0.0297 I °F.
The Overtemperature ~ T reactor trip setpoint pressure coefficient K3 shall be equal to 0.00135 / psi.
The nominal Tavg at RTP (indicated) T' shall be less than or equal to 588. 0 °F.
The nominal RCS operating pressure (indicated) P' shall be equal to 2235 psig.
The measured reactor vessel~ T lead/lag time constant 11 shall be equal to 8 sec.
The measured reactor vessel~ T lead/lag time constant 12 shall be equal to 3 sec.
The measured reactor vessel~ T lag time constant 13 shall be less than or equal to 2 sec.
2.10.9 The measured reactor vessel average temperature lead/lag time constant 14 shall be equal to 33 sec.
2.10.10 The measured reactor vessel average temperature lead/lag time constant 1s shall be equal to 4 sec.
2.10.11 The measured reactor vessel average temperature lag time constant 1e shall be less than or equal to 2 sec.
2.10.12 The f1 (~I) "positive" breakpoint shall be +10% M 2.10.13 The f1 (~I) "negative" breakpoint shall be -18% M 2.10.14 The f1 (~I) "positive" slope shall be +3.47% I% ~I.
2.10.15 The f1 (~I) "negative" slope shall be -2.61 % I% ~I.
COLR BRAIDWOOD 1 Revision 22 Page 11 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT I CYCLE 26 2.11 Reactor Trip System (RTS) Instrumentation (LCO 3.3.1) - Overpower 11 T Setpoint Parameter Values 2.11.1 2.11.2 2.11.3 2.11.4 2.11.5 2.11.6 2.11.7 2.11.8 2.11.9 The Overpower 11 T reactor trip setpoint K4 shall be equal to 1.072.
The Overpower 11 T reactor trip setpoint Tavg rate/lag coefficient Ks shall be equal to 0.02 I °F for increasing Tavg.
The Overpower 11 T reactor trip setpoint Tavg rate/lag coefficient Ks shall be equal to 0 I °F for decreasing Tavg.
The Overpower 11 T reactor trip setpoint Tavg heatup coefficient Ks shall be equal to 0.00245 I °F when T > T".
The Overpower 11 T reactor trip setpoint Tavg heatup coefficient Ks shall be equal to O / °F when T :::'.:T".
The nominal Tavg at RTP (indicated) T" shall be less than or equal to 588.0 °F.
The measured reactor vessel 11 T lead/lag time constant 11 shall be equal to 8 sec.
The measured reactor vessel 11 T lead/lag time constant 12 shall be equal to 3 sec.
The measured reactor vessel 11 T lag time constant 13 shall be less than or equal to 2 sec.
2.11.10 The measured reactor vessel average temperature lag time constant 1e shall be less than or equal to 2 sec.
2.11.11 The measured reactor vessel average temperature rate/lag time constant 11 shall be equal to 10 sec.
2.11.12 The fz (111) "positive" breakpoint shall be 0 for all 11I.
2.11.13 The fz (111) "negative" breakpoint shall be 0 for all 11I.
2.11.14 The fz (111) "positive" slope shall be 0 for all t.l.
2.11.15 The fz (111) "negative" slope shall be 0 for all 11I.
COLR BRAIDWOOD 1 Revision 22 Page 12 of 12 CORE OPERATING LIMITS REPORT (COLR) for BRAIDWOOD UNIT 1 CYCLE 26 2.12 Reactor Coolant System (RCS) Pressure, Temperature, and Flow Departure from Nucleate Boiling (DNB) Limits (LCO 3.4.1) 2.12.1 The pressurizer pressure shall be greater than or equal to 2209 psig.
2.12.2 The RCS average temperature (Tav9) shall be less than or equal to 593.1 °F.
2.12.3 The RCS total flow rate shall be greater than or equal to 386,000 gpm.
2.13 Boron Concentration 2.13.1 The refueling boron concentration shall be greater than or equal to the applicable value given in the Table below (LCO 3.9.1 ). The reported "prior to initial criticality" value also bounds the end-of-cycle requirements for the previous cycle.
2.13.2 To maintain keff ::s; 0.987 with all shutdown and control rods fully withdrawn in MODES 3, 4, or 5 (TRM TLCO 3.1.g Required Action B.2 and TRM TLCO 3.1.k.2), the Reactor Coolant System boron concentration shall be greater than or equal to the applicable value given in the Table below.
COLR Conditions Boron Concentration Section (ppm) 2.13.1 a) prior to initial criticality 2146 b) for cycle burn ups 2 0 MWD/MTU 2132 and < 16000 MWD/MTU c) for cycle burn ups 2 16000 1525 MWD/MTU 2.13.2 a) prior to initial criticality 2275 b) for cycle burnups 2 0 MWD/MTU 2261 and < 16000 MWD/MTU c) for cycle burn ups 2 16000 1676 MWD/MTU