ML20087P713
| ML20087P713 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 03/31/1984 |
| From: | NORTHEAST NUCLEAR ENERGY CO. |
| To: | |
| Shared Package | |
| ML20087P711 | List: |
| References | |
| TAC-49798, TAC-55219, NUDOCS 8404090301 | |
| Download: ML20087P713 (15) | |
Text
-
\.: .1 4
N Docket No. 50-336 r
' MILLSTONE NUCLEAR POWER STATION UNIT NO. 2 STARTUP TEST REPORT CYCLE 6 t
0 1
w
=
March 1984
~
-I 8404090301 840327
- k. .
p, ,
ii._', _ _ __1 m ;___?_ m
____._______.______________.___.___.______.________.___________.__o
F e
INDEX
- 1.
SUMMARY
~2. INTRODUCTION
- 3. 2 Control Element Assembly (CEA) Symmetry Checks 3.3 Moderator Temperature Coefficients 3.4 ? Control Element Assembly Reactivity Worths 1
'3.5 Hot Rod Drops
- 42 POWER ASCENSION TESTING - CYCLE 6 4.1 Power Peaking, Linear Heat Rate, Incore Tilt.
- "4.2 Critical Boron Measurements
'4.3 Moderator Temperature Coefficients 4.4- Doppler Only Power Coefficient
'4.5 Reactor Coolant System Flow
^
4.6 Power Distributions 4.7 = Shape Annealing Factor Test 4.8.. Reactor Coolant System Chemistry i, .
' 5. REFERENCES Figure 1 Cycle ~6 Loading Plan
- Figure _2 CEA Layout -
Figure 3 100%' Power Distribution 14AP - Cycle 6 W
('
i
- 1. SUMARY - Cycle 6 Startup The refueling outage preceeding the Cycle 6 Startup saw a number of unusual events for Millstone Unit 2. In particular the Thermal Shield was removed from the Core Support Barrel of the Reactor
. Vessel. Also, Millstone 2 experienced some fuel failure events during Cycle 5 and fuel sipping was performed for the first time during this outage to remove fuel pin leakers from the Cycle 6 core.
The results from this startup testing program were routine with 2 exceptions:
- 1. Identification of Some Fuel Failures Peactor Coolant System Iodine - 131 levels show that a small
~
number of fuel pins are failed. Based on the Iodine 131 levels at the time of this report, the number of failed pins seem similar.to the number failed in Cycle 5.
- 2. Power Distribution Radial Shift At power measurements show that more power is being produced in the center of the core than what was expected / predicted. This shift in power towards the center of the core over what was T
predicted resulted in several problems. Higher Fxy peaking factors were measured than what was predicted, resulting in the inability to go higher than ; 85% power without a Technical T
,Specifica' tion Change to allow higher Fxy limits. The shift in radial power to the center of the core is demonstrated in Figure 3. .Also it is believed that the CEA worth disagreements that were identified during Low Power Testing were in part due to this power distribution shift.
- 2. . INTRODUCTION Millstone 2,' Cycle 6' fuel loading was completed on December 12, 1983.
The attached Core Map (figure 1) shows the final core geometry.
Subsequent operation / testing milestones were completed as follows:
.t
.)
^
a -
'V.
. Initial Criticality!- Jan. 5, 1984
. . Low Power Physics Testing: Completion Jr.n. 7, 1984 Turbine On-Line' Jan. 13, 1984 Complete 50% Power: Testing -Jan. 20, 1984
~
Complete 83% Power Testing Jan. 27, 1984
-Complete 100% Power Testing Feb. 3, 1984
~
Cycle 6. operation is'with ; 90% Westinghouse fuel and 10% Combustion
' Engineering fuel. The Safety Analysis..is supplied by Westinghouse.
During the outage preceeding this startup, the thermal shield was removed from the Core Support Barrel inside the Reactor Vessel. In
- addition the fuel loading plan was revised'during the outage to I
eliminate. failed fuel identified by sipping. These items were discuss'ed with the NRC and docketed.via other transmittals.
~~
- 3. LOW POWER PHYSICS TESTING RESULTS
-2 Low Power Physics Testing was conducted at a power level of g 10 %
5 power.
?3.1 Critical-Boron Concentrations-
/ Critical Boron Meas'urements were taken at 2 Control Element Assembly (CEA) configurations, all' rods out (ARO) and with CEA banks 2 thru 7.inserte'l(See d Figure 2, CEA MAP).
, rThe Critical' Boron Concentration (CBC) measured with CEA group 7 at 138 steps was 1262 ppm. Adjusted to all rods.out,~the CBC is11271 ppe. ie,-
, -Measured - 9' BOL-HZP-ARO .1271; ppm Boron
~] ,
- Predicte'd 0 BOL-HZP-ARO 1275 ppm Boron A' = ^ f.4 ppm
~
~
. Acceptance . C'riteria t '85L ppm .
' AcceptancezCriteria Met? Eyes s
L
2
^ ~
. The Critical. Boron Concentration (CBC) measured with CEA groups
-7 thru 3 inserted'and group 2 9 10 steps was 908 ppm. Adjusted
, _to CEA groups 7-2 inserted, the CBC is 907 ppm Boron. ie, Measured ' CBC BOL-HZP-2-7 CEA 909 ppa Predicted CBC - BOL-HZP-2-7 ' CEA 895'ppe A= 14 ppm Acceptance' Criteria =
- 85 ppm Boron
~
Acceptance-Criteria Met? Yes
~3.2L Control Element Assembly (CEA) Symmetry Checks
- Millstone 2 performs-rod swaps among CEA's in a bank of CEA's to. verify-that unexpected flux tilts'are not present from either a' core misloading, CEA problem or other reactivity
/ anomaly. Results of the CEA symmetry checks are expressed as the largest' deviation-(in cents of-reactivity) of any CEA from
~the average CEA for that CEA. bank.
1Two sets:of" values are given, raw values.and corrected values.
- The corrected values take into account the-slight design; tilt, since the._ core is not exactly-1/8 core symmetric. The raw values
- are.those values corrected for temperature but which
. assume the core is'.-1/8 core symmetric.
[Thieresultswere:
f' Maximum Value of. Maximum Value of
-Raw Deviation (4)- Corrected Deviation ($)
.564 Bank:1.CEA's 1.144
- " .734 .46&
iBank 3 CEA's-1 Bank'A CEA's: -1.144 .664
, Bank B CEA's. 1 01$ .724
~
n
]*
' f :,
J ;_s _'_.._w ,.-. . ..__2._--. - - . _ _ . _ . - _ . - - - . - - _ _ _ . _ ~ . . - _ - _ _ - . - _ _ _ _ . . _ . - . - . _ _ . . _ . - _ - . . - - - _ - _ _ _ . - _ _
Acceptance Criteria i 2.5$
Acceptance Criteria Met? Yes (Note B,ff = .60 M AD 3.3 Moderator Temperature Coefficients Moderator Temperature Coefficients are measured at 2 critical CEA configurations. All rods out and with CEA banks 2-7 inserted.
'All Rods Out Measurement The measurement @ 528.1*F, CEA 7 @ 138 steps and a boron concentration of 1262 ppm was +.447 x 10 ~4 AP/*F.
' Converting this measurement to its most positive value (All
~4 Rods Out) increases the MTC to + 455 x 10 AP/ F.
~4 Measured value of MTC @ 528.1"F BOL-HZP/AR0 +.455 x 10 AP/*F Technical Specification MTC Limit /Must be
~4 no more positive than + .50 x 10 AP/ F
~4 A=- .045 x 10 AP/ F
, Acceptance Criteria Met? Yes To compare the measurement to the prediction yields:
MTC measured value at 532*F, 1275 ppm
~4 Boron is: .43 x 10 AP/*F MTC predicted value at 532 F, 1275 ppm
-Boron is: .53 x 10 ~4 AP/ F A= .1 x 10 -4 AP/*F
< Acceptance Criteria is i .3 x 10~4'AP/ F Acceptance Criteria Met? Yes
/
__.__._J
a CEA 2-7 Inserted Measurement The MTC measurement with CEA banks 7 thru 3 inserted & CEA bank 2 9 10 steps, temperature = 527.6*F & a boron concentration 908 ppm was .39 x 10 ~4 AP/*F. Adjusted to the vendor conditions @
Baron Concentration of 895 ppm and an average temperature of 532*F given-a value of .44 x 10 ~4 AP/ F. Therefore-Predicted MTC 9 532*F, 895 ppm BOL/2-7 inserted CEA .31 x 10 ~4 AP/ F Measured MTC 0 532*F, 895 ppm 80L/2-7 inserted CEA .44 x 10 ~4 AP/ F A= .13 x 10 ~4 AP/*F
~4 Acceptance Criteria = 1.3 x 10 AP/*F
. Acceptance Criteria Met? Yes 3.4 Control Element Assembly Reactivity Worths Reactivity worth measurements were performed twice on CEA banks 2 thru 7. All measurements were taken with each CEA bank moving alone with no overlap from other CEA banks.
RESULTS OF THE MEASUREMENTS WERE:
(M-P/P)
.CEA BANK- MEASUREMENT ' PREDICTION DELTA % DIFFERENCE 7.- .615% AP- .655% AP .040 - 6.1%
6 .297 .328 .031 - 9.5%
- 5 .325 .276 +.049 -17.8%
4 .910' '1.080 .170 -15.7%
3 .612 .614 .002 -
.3%
'2
'1.011 1.108 .097 - 8.8%
'( .
l
- Acceptance Criteria on Total Worth CEA Groups 2-7 inserted is 1-10%
Acceptance Criteria Met?.-.Yes Acceptance Criteria on' individual CEA banks is either i 15% or within i .1% AP.
Acceptance Criteria Met?,IYes, on all banks except on Bank 4.
' Bank 4 does not meet acceptance criteria. It is slightly in excess of-i 15%.
Due to the' disagreements.found in the CEA worths, in particular CEA group 4, Westinghouse was consulted while Low Power Testing was'.in progress'. Westinghouse reviewed CEA group 4 being slightly
! :out_of acceptance criteria to determine whether the safety
. analysis was affected. They concluded that the measured results w of.CEA group'-4 worth'was-acceptable. This evaluation included shutdown margin, trip l reactivity and power peaking factors.
- '3.5 shot Rod Drops
~
Hot. Rod Drops were performed on all 61 CEA drive mechanisms.
The drop times from 0_to 90% insertion ranged from 2.02 to 2.31
. seconds for all CEA's.
Acceptance Criteria: All CEA's must drop'from 0 to 90%
' insertion ~in less than' 2.75. seconds, per technical
- specifications.
Acceptance Criteria Met? Yes
~
J 4.; : POWER ASCENSI'N O TESTING ~
4'.1, Power Peaking, Linear Heat Rate and Incore Tilt Measurements
~
-- .were:
~
. Power Level: N FrT Max. Linear Heat Rate Incore Tilt
.. 50%' Power J1.682' 1.532 17.13 kws/ft .008
~'
- 83% : 1.661 ' 1.5251 '11:30 kws/ft .008
,. 100%: , 1.670 ' 1.519.- 13.24 kws/ft' .006 g m- ,w w,- ,e.+,w.w , ,,w w -r > e --
7 J.
l Corresponding Technical ~ Specification Limits Are:
. Power Level -FxyT ppT Max. Linear Heat Rate. Incore Tilt 50%. 1.836 1.705 15.6 kws/ft .02 83% 1.785 1.605 15.6 .02
-100%' 1.719 1.565- 15.6 .02 Techanical Specification Limits Met? Yes MDTE: A Technical 5;acification change was processed for FxyT
-limits prior to plant power increasing above 83% power.
l4.2 ' Boron Measurements At 50%. power, 50 MWD /MT, AR0, Equilibrium Xenon, the measured Boron Concentration was 1005 ppm.
Measured 50%' Power, ARO, EQ Xe, 50 MWD /MT 1005 ppm Boron Predicted 50% Power, AR0, EQ Xe, 50 MWD /MT 1019 ppm Boron A= 14 ppm Acceptance Criteria = 1 85 ppm Boron
' Acceptance Criteria Met? Yes At 100% power,- 400 MWD /MT, ARO,'Equilibium Xenon, the measured Boron Concentration was 880 ppm.
Measured 100% Power, ARO, EQ Xe,'400 MWD /MT 880 ppm Boron
' Predicted 100% Power, AR0, EQ Xe, 400 MWD /MT 884 ppm Boron b -
A= 4 ppm i~
, , ; Acceptance Criteria = 1 85 ppm Boron Acceptance Criteria Met? Yes R
4 --
-6 4.3' Moderator Temperature Coefficient 9 83% Power The MTC measured at 83% power with CEA 7 at 150 steps,
-4 T,y, = 561*F, 915 ppm Boron was .14 x 10 AP/*F. Adjusted to the predicted MTC conditions given; Predicted MTC .9 563*F, 915 ppm, 83% power is -
. 22 x 10 ~4 AP/*F Measured MTC @ 563*F, 915 ppm, 83% power is -
. 17 x 10 -4 AP/*F A= . 05 x 10 ~4 AP/*F Acceptance Criter.ia-is t .3 x 10 ~4 AP/*F Acceptance Criteria-Met? Yes
~4.4 Doppler Only Power Coefficient The doppler only power coefficient was measured at 81.5% power, t
T,y,-= 566.5 and Boron = 915 ppm. The measured value at these :
conditions was .89 x 10 ~4 AP/% Power.
i
. Adjusting;the measured value to the conditions of the prediction yields:
' Measured Value: -
. 89 x 10 ~4
- AP/% power.
-4
-Predictsd Value
. 92~x 10 . AP/% power
- A =. . 03 x 10 ~4 AP/% power-Acceptance' Criteria i .3 x 10 -4 AP/% power
-Acceptance ~. Criteria Met? Yes
~
4.5 RCS Flow 9'100% Power .
1 The measured RCS flow at 100% power was 378,800 gpm.
' Acceptance-Criteria is > 350,000'gpm Acceptance Criteria Met? .Yes 4
4 f
-FT f eJ 1- +1ts J + g w: y V Wv--*5p --
++yW4 F'gs- yyp-ye - gey ++g-yr--s y fq-Nr1 n+g ep-yFT- -# -pg>--- t -Peyv--Tw's
t e
4.6 Power Distributions A Power Distribution Map at 100% power, 500 MWD /MT is shown in Figure 3. This map shows the agreement between measured and predicted-Relative Power Density for each assembly in an average.1/8 core octant. While acceptable, it does show an unexpected higher power core center region with corresponding lower power peripheral fuel assemblies. .
' Acceptance Criteria: All locations with i 10%
Acceptance Criteria Met? Yes 4.7 Shape Annealing Factor Test-In response to the thermal shield removal, a Shape Annealing Factor Test was performed at 50% power. This test was designed
'to ensure that accurate constants were being used for Axial
~
' Shape Index (ASI) inputs to the Reactor Protection System.
-Results of the test showed essentially no change in Shape Annealing Factor since they were measured during initial plant startup. The new Shape Annealing Factors were input to the Reactor Protection System. The table below shows the results for the 4 safety channels.
~
Cycle 1 S.A.F. Cycle 6 S.A.F.
Channel A 2.195 2.267 Channel B 1.738 1.783 Channel C '2.142. 2.116
- ' Channel D 1.851 1.870 4.8 Reactor Coolant System Chemistry Reactor Coolant System (RCS) Chemistry.up to 83% power testing showed_ low activity levels in the RCS. Iodine 131-values were 10
-3 Ci/ml or less up to and including the 83% power plateau.
1--
-Within a few days of reaching 100% power, RCS activity levels experienced significant increases in. total activity as well as I-131 increases. After several weeks of operation, Iodine-131 levels as of this writing were stabilizing around a value of about .07 pCi/ml Iodine-131. This is indicative of a small number of failed fuel pins.
5 .' REFERENCES
~
5.1 Inservice Test T83-42, Low Power Physics Testing for Cycle 6 5.2 Inservice Test T83-43, Power Ascension Testing for Cycle 6 5.3 Westinghouse Nuclear Design Report - Cycle 6 JP: d'1p.
f P
A s J
1 6
'~
FIGURE I
$ s.
eram m 5
ApppovAL: E'
- DATE:
3 Rf ACTOR INGiNEER 1 2 3 4 5 6 7 8 9 to 11 12 13 14 15 le 17 18 19 20 21 I I I I I I IIIIlllll l l l l 1 l
,_ M37 HT H2L H4o H39 M46 H L4 FSB *HIM F37 H72 H24 .
HS2 3i 40 ,
H3b Aol3 H81 A0bl M22 fot Ho4
'~ AOCSHt3 fo4 MSq IM 25 11 4 *1 SS v- H67 Hil G "li A048 H l2. F70 Gol F4o H24 A069 G4r H81 HSL 6*7 19 3o 39 51 69
,_ N44 Fl4 G71 GSo G li F44 S 12. G38 GIS F36 Gol G33 G69 A014 H3t 6 9 24 P 46 P 63 s- H45 H75 4037 G20 F74 H35 F64 G59 F45- H74 8021 G2n Ao32 HFI HSg to n So 59 .
,_ HL2 AoSL H2O F69 Hgy Fob G36 F45&3l . F03 Hil F4t HI6 AoT4 H35
, __ H43 5 83 23 34 4s" 54 61 H33
, _ _ FSL Hi9 Fbi GO8 F53 G65 Fo5 G42 FAO G48 F.26 Gl3 F21 Mii FSR
,_ H 2'? 2. 9 21 3R SR 6f H41 g_ H06 F17 G;8 G61 GS1 F47 G2R F'12 G44 F27 G49 G40 Gl1 FlS' Hoy K-
,_ F49 H03 FS5GO3 FSI G34 Fo9 G15 flo GSy F31 Gl6 F30 Ho8 F63 H-c- H2TAOSt H2l F3 H19 Fi8 GS3 F25GML Fi6 Mtz Fit H lo Aoos H40 4 12 2: 32. 43 53 6
,_ H69 HJ8 Ao48 G23 Fl9 H8L F54 Gsg Fs7 H76 Fl3 G06 Acts H&b HG3
. e 'l I6 49 SL
~ ,_ H67 Ao60 G29 G64 GIS F28 &l4 G30 Go*1 F46 Go1 G31 G43 FII H34 3 P 2o P 42 "P Go o_ His Hol G27 Ao2l Ho*7 F6) G22 F42 Ho2 A00f G70 HDT
, _ HS3 H54 H47 F67 H23 FS1 H55H48 H2O 2b- e 35*
_, __ H38 H49 H21 M61 C yc.le 6 2 g
f s.,,,ioca.g N ""
I X 11 NN 2 S t\ SW 3 F3 sW . c 4.
y 3$ 5g utv.o 2_u_n
E' FIGURE 2
'igt as s t aan m36 pggyg 4
130 83. at. .3. ' d. Att 63. rte it.
3-69 3-58 et. .19 61. Jt. 41. Flp sts ett vtB 119 sts A-49 4 - 57 7-38 4- 50 A-42
.. ii. ii. .i. 6:e si. si. .. ci. .i. . ci.
.. vi. '
7-68 A-49 1-33 1-76 L-47 7-59 _
L17 Jt? 617 ft? (17 .17 Cl? .47
- st? e l? vl? tt? Sl? et? .47
.A-48 2-25 2-18 A-43 .
.. .. ii. ,i. .i. ri. :i. .. ci. ..
ii. .. .. ti. ii. .
4-48 5-17 5-14 A-43
.35 L15 J15 618 ftS til ,D i l CSS 815 stl *18 ; vl5 til ,
816 all vu 4-56 2-24 B-9 5-2 B-6 2-16 4- 51 a13 .t3 L13 Jtt sta Ft3 EIS 013 CIS 913 113 wt3 vt3 113 SIS "8 1-32 B-9 B-6 1-27 3.60 3-67 .1% Fil Ell ett Clt pts sll uit vtt Ttt all all .11 L11 'Jll 7-39 a'*
C 7-41 5-5 7-1 5-3
,. re a. .. c. ..
. we v. te se .. .. 6.
C 3-66 1-31 B-8 B-7 l-28 w? v7 77 67 a? .7 L1 J7 .7 F7 L7 .7 C7 3.761 37 4-55 2-23 B-8 .5-4 B-7 2-20 4-52 o ..
is s
4-47 is E-16
.i .
to es ..
5-15 es os 4-44 es es 2-22 2-21 A-44 A-47 64 f4 to 4 C4 we we T4 84 .4 .. L4 AS 7-65 .4-46 l-30 l-29 .l-45 7-67 L3 53 F3 E3 B3 v3 T3 33 m3 .5 lJ3 A-46 4-54 7-40 4-53 A-45
.: .3 .: 6: .: .: en is 1:
5-64 5-63
.i .i ,
ai ..
- REACTOR CORE CEA AND EXCORE DETECTOR LOCATIONS D
e 9
e e
e e G
e r -_
- FIGURE 3' '
RADIAL' POWER DISTRIBUTION MAP 100% Power, 500 MWD /MT-Burnup All Rods Out, EQ, Xenon . - .
Millstone 2 Cycle 6' TOP - Predicted Relative Power Density MIDDLE'- Measured Relative Power Density
. BOTTOM - % Difference (MEAS-PRED)/PRED 1.113 .687 1.096- .685 8
-1.5% .3%
1.165 1.183 .671 .569 1.126 1.175 .683 . .576
-3.3% .7% +1.8% +1.2%
.899 .975 .835 1.140 .891
.903 .912 .830 1.125 .867
+.4% -6.5% .6% -1.3% -2.7%.
.937 1.241 1.035 1.244. .871 1.069
.980 1.263 1.037- 1.233 .880 1.046
+4.6% +1.8% +.2% .9% +1.0% -2.2% .657
.638
.929 1.165 1.056 1.056 1.084 1.245 .945 -2.9%
.984 1.202 1.058 1.037 1.086- 1.238 .958
+5.9% +3.2% +.2% -1.8% .2% .6% +1.4% .880
.861 1.099 1.220 1.090 1.175 1.258 1.040 .937 1.198 -2.2%
1.170 1.288 1.140 1.213 1.251 1.012 .949 1.191
+6.5% +5.6% +4.6% +3.2% .6% -2.7% +1.3% .6%