ML19209C458

Control Element Assembly Guide Tube Insp Program, Nonproprietary Version

ML19209C458
Person / Time
Site:	Calvert Cliffs
Issue date:	10/08/1979
From:	ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY
To:
Shared Package
ML19209C437	List: ML19209C436 ML19209C458
References
CEN-116(B), NUDOCS 7910150592
Download: ML19209C458 (33)

Text

'

's Combustion Engineering, Inc.

Response to Request for Additional Information CEA Guide Tube Inspection Program

- Calvert Cliffs Unit No. 2 Docket No. 50-313 CEN-116(B)-(NP)

October 8, 1979 e

i145 386 7910150 5 7.2,

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P00R OR K 1 LEGAL NOTICE THIS REPORT WAS PREPARED AS AN ACCOUNT OF WORK SPONSORED BY COMSUSTION ENGINEERING, ifJC. NEITHER COMDUSTION ENGINEERING NOR ANY PERSON ACTING ON ITS BEHALF:

A. MAKES /'.NY WARRANTY OR REPRESEtJTATION, EXPRESS OR .

IMPLIED INCLUDING THE WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MEHCHANTABILITY, WITH RESPECT TO THE ACCUCACY, COMPLETENESS, O3 USEFULNESS OF THE INFORh% TION COTJTAINED IfJ THIS REPORT, OR THAT THE USE OF ANY INFORMATION, APPARATUS, f.'.ETHOD, OR PROCESS DISCLOSED IN THIS REPORT MAY NOT INFRINGE PRIVATELY OWNED RIGHTS; Oft B. ASSUMES ANY LIABILITIES WITH RESPECT TO THE USE OF, OR FOR DAMAGES RESULTING FROM THE USE OF, ATJY INFORMATION, APPARATUS, METHOD OR PROCESS DISCLOSED IN THIS REPORT.

1145 087

1_

A. All Cate_gories of Fuel Assemblics Question (1): Provide Cycle 2 and Cycle 3 core maps identifying Category la,

. lb, and 2 core positions. Identify in tabular form 3t the assembly category, exposure, wear time, CEA type, high crimp ECT signal, average crimp ECT signal, pull test results, recrimp, general comments, and' any other pertinent characteristics which

. are considered important for evaluation purposes.

Response: Cycle 2 and Cycle 3 core maps are attached, showing the core positions for the various categories. The lists belotg abulate the assembly serial numbers for the various categories }. All assemblies have been or will be located under full length CEA's

- (part length CEA's have been replaced by plugs). ECT data and pull test results will be transmitted at a later date.

Category la - Unworn cuide tubes, sleeved unirradiated -

a. Under CEA's during Cycles 2 and 3 D001 0012 D103 D003 D015 D107 0007 D019 D108 D010 D047 D109

b. Under CEA's during Cycle 3 Only D106 Dill D113 0115 D117 Dil9 D110 D112 D114 Dll6 D118 D120 Category lb - Unworn cuide tubes, sleeved irraJiated,3 under CEA's durino Cycles 2 and 3

' C002 C0ll C024 C034 C003 C012 CO27 C036 C004 C017 CO29 C037 Category 2 - Demonstration Assemblies p  !

k 5 v.

Il0TE: (1) The fuel loading pa ttern presented on the following pages, and therefore the tabulation of fuel assemblies above, are preliminary. lhe assemblies involved may be changed due to late fine tuning of the core design to accor.nodate up to date burnup inforr:ation available for Cycle 2. "est likely, those assemblics to be reluccted would be intercilanged with assemblies of the same batch.

i145 088

2_

_ CYCLE 2 C01:E M;P 0

1145 089 u

CYCLE 3 CORE ltAP i

.I t

e e

4 1145 090

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Question (2):

Describe and discuss the ECT and pull test that will be performed in-core and out-of-core Response: Eddy Current Testing in-core Eddy Current Testing will be conducted upon that fuelassemblieswhichhavebeenunderCEA'sduringCycle(2.] A[ category?

determine the axial]of eddyofcurrent position maximumcoil wear will be employed if present, andfirst as atoscreen-

" ins technique to determine which guide tubes should be further inspected.

A[ jeddy current coil could then be used to provide more definitive information about the degree of guide tube wear.

The other fuel assemblies which will be eddy current tested ere category la and lb, i.e., sleeved, one and two cycle assemblies which will be under CEA's during Cycle 3. The emphasis for eddy current testing these categories is to determine the crimp size and therefore itr adequqacy for use in CEA locations. 'he eddy current equipment is identical to that.used for category 2 assemblics. Comparis)n of the eddy current sianals with that for a known standard will allow crimp size determination which may then be judged acceptable or not acceptable for use.

it is not certain at this time exactly where this eddy current testing will be performed, but is anticipated that it will take place out of core. The extent of the testing of the various categories of fuel assemblies is discussed in responses for sections B, C and D.

Pull Testing

, Pull testing of the sleeves is conducted out-of-core. The procedure for pull testing is similar to that utilized during sleeve installation.

The tool has elastomers at its lower end which are expanded to grip the sleeve, butwnich do not deform it so as to nake contact with the upper end fitt' Dost I.D.,

Anaxialloadisappliedgraduallyuntila[

applied to the sleeve. Should there be motion of the sleeve prior to

]is reachingthe{ 3 which point motion was dete,the ctedcmount of motion is recorded, and and the loadresumed the loading value at until[ ]onthesleeveisreached. >

l .._ s.

. 1145 391

Question (3): Describe the fuel handling criteria for each of the fuel categories.

Response: Category 1 fucl assemblics were steeved prior to their use under CEA's. Based on inspections of identical slee"es at other C-E reactors, the sleeves are not expected to have sustained measurable wear while operating under CEA's. The guide tubes in these assemblies should thus be unworn and the bundles may be lif ted and handled norrally.

Category 2 fuel assemblies had features intended to mitigate wear andwere,therefore,used(( ] Handling criteria for hese fuel assemblies are identical to those used for the[ Cycle i bundles that ucre under CEA's Sect, ion III. 1. of Amendment 2-P to CEN-83 (B)-P). l>(pee In the unlikely event that wear thru the sleeves and into the guide tubes is discovered in Category 1 fuel, these same criteria would be applied.

Question (4): Compare and discuss any observed differences in measured BOC2 and E0C2 ECT results.

Response: ECT inspections at BCC2 consisted of guide tube wear measurements on all fuel assemblies that were in CEA locations during Cycle 1.

These data are s 7marized in CEN-101-D-P, Amendment 3-P, dated October 12, 1978 Following the Cycle 2 shutdown, ECT measurements will be rade on the

[ ] demonstration assemblies that were(( '3in CEA locations during Cycle ? These data and an evaluation will be suppli:d af ter.

they become aval oble.

There were no ECT measurements made on the sleeves tnat were instailed at 80C2, so no comparisons can be made with the sleeve data to be taken during this shutdown.

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Reference:

(1) Ltr., A. E. Lundvall (BG&E) to R. W. Reid, (NRC) dated 3/17/78 (2) Ltr., A. E. Lundvall (BG&E) to R. W. Reid, (NRC) dated 10/16/78 1145 392

B. Category la Fuel Assemblies Question (1): A minimum of five (5) sleeved Batch D assemblies should be selected to confirm crimp adequacy. We also suggest a minimum of three (3) pull tests on those sleeves which exhibit the lowest ECT indications at the crimp. If any of these sleeves fail-the pull test, the number of pull tests should be increased.

Response: Based on preliminary Cycle 3 core management information as well as E0C IIg'uidetubeweareddycurrentdata,{ )sleevedBatchDassemblies have been selected to verify crimp adequacy. These assemblies and some characteristics of the cycle 2 and 3 core positions of each are:

Assembly CORE LOCATION CliARACTERISTICS Number Cycle 2 Cycle 3

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The ECT results from these assemblies will be reviewed together with the results of the Category 1(b) assembly ECT work to make a determination of samples for pull testing since crimps of similar design were used for both.

It should be added that the crimp geometry and expansion steo used for the Batch D assemblies sleeved fresh in 1978 were identical to those used on the fresh Calvert Cliffs II Batch E assemblies sleeved in Sep ten.be r , 1979. Eddy current testing of these Datch E assemblies indicated thatallcrinpsexceededtheminimumexpansionrequirements( ]

• These locations are identified as[ .]corepositions' as a result of the LOC I excm program.

1145 393

. Question (2): Provide your correlation of crimp adequacy versus pull test results for the new crimp design and compare these results with the old style crimp design results.

Response: There is no pull test data available at this time for the new crimp design. As explained in the response to Question (C4), a limited number of sleeves with the new crimp design will be pull tested during the outage. There is no reason to expect that these sleeves

, would be more susceptible to pullout than sleeves with the old crimp

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design and they are actually expected to perform better since they have a sharper, more clearly defined curvature in the crimp region.

Question (3,); Discuss the recrimp or reexpansion criteria proposed for the Category la assemblies or the sleeves which have been pull

. tes ted.

Res ponse_: Sleeves in Category la fuel assercblies must satisfy the same criterion on crimp size which is applied to Category lb assemblies.

This minimum size is[ ](see response to Question (C6)).

b 1145 394~

C. Category lb fuel Assemblies Question (1): This category of fuel assemblies resulted in inadequate crimps at CCf!PP-1. Verify that the crimping procedure used at CCflPP-2 included the pull test prior to the expansion step.

esponse: The crin.ging procedure used at CCNPP-2 was 00000-ESS-107 Revision 02,

'JProcedure for CEA Guide Tube Repair of C-E Fuci Assemblics." The procedure specified that the pull test be perfonned prior to the sleeve exapansion steps.

uestion (2): State how many of these assemblies will be discharged, and how many will go into non-CEA locations.

esponse: Category lb fuel assemblies are defined as-bundles that were sleeved af tdr irradiation during Cycle 1, were operated in the reactor during Cycle II, and are to be loaded in CEA locations during Cycle III.

In addition to the Category lb assemblies, +here are also thirty-seven bundles (Batch B) that were sleeved after operation in Cycle 1 and then located under CEA's during Cycle 2. These will all be discharged.

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pon (3): Propose a minimui.  :'mber of visual examinations to inspect for guide tube cracks in the region of the crimp.

Resconse: C-E has completed extensive poolside and hot cell examination programs aimed at confirming satisfactory sleeve / guide tube performance. These programs have provided the following information:

(a) Hot cell results from expansion tests of an irradiated sleeve and Zircaloy-4 guide tube sample set were repnrted in Reference (1). _

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' Reference (1): 'rSleeve Fuel Assembly inspection Results at Calvert Cliffs Unti I",

Cell-lll(B)-P, dated !1ay 1979 Ltr., A. E. Lundvall (BG&'E) to R. W. Reid (NRC) dated 5/31/79

These tests showed that irradiated Zircaloy-4 can accommodate deformation well in excess of the specification limit for crimping with no deleterious effects.

(b) In 1978, fuel assemblics at both Millstone II and Calvert Cliffs I were visually examined by periscope af ter sleeving in the. vicinity of the crimp and no guide tube anomalies were observed. In April, 1979[ ] fuel assemblies were visually inspected by periscope at Millstone II after one irradiation cycle in the sleeved condition.

Again, no anomalies were observed c: any of the guide tubes.

• Detailedhotcellexaminationofasetof[ ) irradiated sleeve /guid'e tube samples taken from a liillstone 11 fuel assembly also confirmed the absence of guide tube anomalies.

Based on this information, the condition of sleeved guide tubes after one operating cycle (e.g. assemblies at Calvert Cliffs II) is considered adequately characterized without any additional inspections at Calvert Cliffs II.

1145 396

C. Category lb Fuel Assemblies _

Question (4.1,:. Specify a minimum number of pull tests to be perform The basis may include, but not be limited the basis for selection.

to, the following considerations:

a. Low ECT ciimp signal, b.

flon-CEA location in Cycle 3 with low ECT crimp signal,

c. Observed fractures in guide tube crimp region,

d. Axial position change,

e. Discoloration in sleeve or guide tube and/or

f. Cycle I wear considerations.

Itisanticipatedthataminimum6f[pulltestswi'lbeperformed.

'.:wse :

However, the specific number of guide tubes and number of differe assemblies involved will be determined after inspection retuits are obtained. The bases for selection includes: 7 i

a

. 1145 097

Ques tion (5): Do you propose a pull-to-destruction test of Category lb sleeves?

If not, provide your justification for elimination of these tests.

Response: As explained in the response to the next two questions, Category lb sleeves must satisfy a minimum crimp size criterion or be recrimped to meet that criterion. Complete sleeve withdrawal has been performed on one sleeve in both Millstone 2 and Calvert Cliffs 1

. assemblies. The crimp sizes of these sleeves, which were comparable to the sizes expected for the discharged Calvert Cliffs 2 Batch B bundles, were smaller than the minimum crimp criterion to be used at Calvert Cliffs 2 for CEA locations. Maximum withdrawal force jat Calvert Cliffs 1.

was{ightofthese{,]at In l Millstone 7 and[

j forces for sleeves with small crimps, it is not considered necessary to conduct a pullout test in a Calvert Cliffs 2 fuel assembly.

Question __(6): What criteria determine the need for recrimping? .

Response: The sleeves must have a[ ] minimum crimp size. The basis for this value is explained below. .

Duringhotoperation,the{ ]differentialthernalexpansior, between the stainless steel sleeve and zircaloy guide tube will cause the two components to be in intimate contact over the expanded

' length of the sleeve [ lea gap betvieen tne two was set ] The to ensure

[ this condition.]maxinuminstal The(_ ] minimum outward crimp of the sleeve was chosen as a conservative size that would prevent withdrawal of the sleeve Realistically, upward thru the non-crimp]ed crimpsassmallas{ region are capable of of the guide performing tube.

this function even af ter long term operation (since the cold gap would not exceed the[_ 3 differential thermal expansion, even with relaxation values approaching 100%).

Question (7):__ 'What is your acceptance criteria for a recrimped sleeve?

Response: Thesame[ 3 minimum crimp size, discussed in the previous section, must be shown by ECT inspection of recrimped sleeves.

1145 098.=

Question (8): What visual examinations will be performed after the recrimp procedures? '

Response: The visual examinations which will be performed after recrimping would be those specifica oy tne procedure for recrimping, i.e., a TV camera inspection of the top of the fuel assembly to ensure that m tools or debris are on the assembly; to verify proper axial seating of the sleeves with respect to the upper end fitting posts.

Question (9): Specify if pull tests will be performed on any of the recrimped. sleeves.

Response: In the event that recrimping is required, pull testing of the recrimped sleeves will not be performed since for newly installed or recrinped sleeves it is an indication of pullout resistance prior to themal cycling.

As explained in the response to Question C.6, the effects of operation may tend to increase the gap between the sleeve and guide tube. There-fore, crimp size is the important paramater to ensure long term resis-tance to sleeve pullout. An Eddy Current Test of the recrimped sleeve will be performed to determine the magnitude of the recrimp. The size of the recrimp will be compared to allowable limits to insure positive sleeve retention within the guide tube.

Ques t_i_on (10): Will reexpansion be performed following the recrimp?

Response: Reexpansion of the sleeve for the first two inches will be performed

-after the sleeve has been recririped, lhese sleeve reexpansion r.teps are to close any local gaps which may be created by the recrimping process.

Question (11)1 If reexpansion is performed, will it be before, or af ter, a pull test?

Response: As stated in the answer to C.9, sleeve pull tests will not be performed, rather, Eddy Current Testing of the recrimped sleeve will be perfomed to ensure the crimp adequacy. The Eddy Current Testing is performed after the sleeve reexpansion steps so that a final sleeve configuration is tested.

1145 099

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D. Category 2 Fuel Assemblics 300ROR8!RI -

Question (1): What criteria' has been established for continued, or discontinued, use of the Category 2 assemblies in CEA locations, and/or non-CEA locations?

Response: No Category 2 fuel assemblics, sleeved or unsleeved, are going into CEA locations for Cycle 3. Detailed analysis of the ECT results from these bundles would be required to justify their use in CEA locations in future cycles. For non-CEA locations, the criteria for determining whether the bundle can be reused either unsleeved or sleeved, or not reused at all, are identical to the criteria applied to the worn fuel asserrLlies at E0C1. (See response to question D-4).

,uestion Q _(2): What criteria determines how many guide tubes will be azimuthally eddy-current tested for local wear?

Response: The number of guide tubes requiring [ ]ECT depends on the results of the[ ]ECT, as it did for E0Cl worn bundles.

The[ ] data ,gives an indication of the magnitude of average wear on the circumference of the guide tube, which, based on compariscns made from earlier data, determines whether stress levels with wear are acceptcble (see Question (D4)). If stress levels cant,0-bedefendedonthebasisofthisscreeningtest,[, ]ECTis required to further define the wear configuration.

Question (,3) 3 WhLt is the minircum number of guide tubes that will be azimuthally eddy-current tes ted?

ResEonse: eddy-The minimum number of guide tubes that will,Jbe{ data which]will be currenttestedcouldbezeroifthe{

taken on all the guide tut,es of Category 2 bundles verifies that the degree of wear indicated would not result in the violation of allowable stress levels. If this cannot be verified, the more detailedfi ] examination would be necessary.

Question (4a): What criteria determines excessive wear requiring sleeving and is the criteria different for CEA and non-CEA locations?

Response: As stnted previously, the Category 2 fuel assemblies are not being loaded into CEA locations. To allow the reuse of these bundles withnut sleeves in non-C[A locations, they must not'have a hole worn thru the guide tube and they must be capable of operation uithout violating applicable stress limits for tSe aorn region (see Section IV. A.3 of CD1-03(C)-P and Secticn IV.B of !.mondment 2-P te thLt ducu;..cnt) .

Rbferences: (1) Ltr.TT ETTuridvall (BG&E) to CStello ' :RC) dated 2/17/D (2) Ltr., A. E. Lundvall (BG&E) to R. W. Reid (NRC) dated 3/17/79 1145 100

Ques tion (4b)) What criteria determines excessive wear requiring discontinued use?

Response: A worn Category 2 fuel assembly could not be reused if, even with the installation of the stainless steel sleeve, the stress levels in the worn region were predicted to exceed the allowable limits. (See section IV.A.3 of CEN 83(B)-P).

Question (5):-~ If sleeving is installed in the Category 2 assemblies and they are placed under CEA's in Cycle 3, or future cycles: a) how will

, sleeving affect scram time; b)CEA cooling; c) local boiling in annulus.

Response: None of the category 2 foci assemblies are located in CEA positions for Cycle 3. Worn, sleeved assemblies have never been used in these positions. If, in. future cycles, Category 2 bundles, either sleeved or unsleeved, tre to be located under CEA's, analyses will have to be prepared to justify their acceptability.

b i145 101

- 15.-

E. CEA Examinatinns Question (1): Specify the minimum number (preferably 5) of CEA's that will be eddy current tested.

Response

The current plan is to eddy current test ( )CEA's. These include

(*

]from peripheral dual CEA positions that exhibited [ ) based on E0C I guide tube inspection results.

Two of these{ ]CEA's are locatedinunsleevedtestassemblieswith{

The( ]CEA is from the core center which was a very( ]

position based on E0C I guide tube inspection results.

Question (2): Describe the ET method, equipment, and the CEA areas tested.

Response: liethod

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For the test. a CEA was lowered into the fixture approxinately three feet, and the CEA was withdrawn, using(she spent fuel handling machine. Tne ] output of the[ jwas recorded on mag tape and a strip chart recorder. Each[ .Jias selected, in turn, and the CEA inserted into and withdrawn from the fixture until all 5 CEA fingers were tested.

The testing was done at 400 kliz and the gain on the El1-3300 set at 50.

Equipment

a. Eddy Current Tester

b. Two Channel 11ag Tape Recorder

c. Two Channel Strip Chart Recorder 4.{ ]

5. , [

6. Ca' . ration Standard

]

CEA Areas Tested i145 102 The lower three feet of all five fingers on the CEA assemblies were eddy current tested.

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Question (3):

100RORSNa Provide information on the ET calibration correlations

Response

The signal amplitudes from the CEA's were comoared to those obtained from testing a CEA wear standard with[

] wear simulations. Thesignalamplitudedependsonthe[

Jofthewearpattern. Consecuently, the

.signalamplitudel.

'} This correlation assumes that the signal is attributed only to weaFwith no associatedl lof the CEA finger. [

J The correlation factor relating signal amplitude to wear typically varied tion. Thefrom one test to another due to variations in test instrumenta-correlation was established independently for each test set-up to relate signal amplitud? to a calibration standard with machined wear of a known dimension, ues tion _(4): Provide the.ECT acceptance criteria.

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esponse:

The degree o'f wear on a control rod is acceptable,for continued operation,if the ECT data jindicates thanaraximumweardepthof[

J q wi th an that,the wear {is n uestion (5):

Specify the minimum number (preferably 5) of CEA's that will be visually examined to characterize the surface appearance of the CEA rods.

esponse:

Eachofthe{ ]CEA'smentionedinquestionE-1.willbe scanned by TV as they are eddy current tested. Based on the ECT and visualinspectionresults,( ]ofthesemaythenbeexamined in more detail either by TV or periscope.

1145 103

E. CEA Examinations Question (6): Describe your method (s) of visual examination, the areas examined, and the reliability of these examinations to detect: fatigue cracking,

. stress corrosion cracking, abrasion, denting, and otner surface characteristics which could impede CEA movement, degrade their function, or reduce their design life.

Response: Both closed circuit TV and periscope have been used for remote visual inspection of the CEA's. Specific surface features can be documented by videotape or 35 nm photographs.

The full length of the CEA's selected for eddy current testing are scanned by TV as they are removed from or returned to a fuel assembly.

Based upon the eddy current test results, as well as results of any previous examinations or observations, CEA's may be selected for additional, more detailed examination either by TV or periscope.

These detailed exams include a scan of each finger of the CEA to characterize overall condition and a more detailed inspection (with extensive documenation) of the bottom two to three feet of each CEA finger where the maximum neutron exposure has been accumulated. The techniques that are used for these visual examinations have been employed by C-E in the past for many different types of poolside inspection programs.

Bcsed on experience, the results of the visual inspections together with the results of the eddy current testing provide a reliable indication of the surface condition of the cladding of each CEA finger.

. 1145 104

Question (7): Because CEA's are subject to multiple cycles, and continued vibration, what supporting test data and criteria provides assurance that unacceptable accumulative damage will not occur within the design life of the CEA's? .

P.es ponse : Flow tests were performed at

, size CEA typicci of those in(Calvert using Clittsa full 2.]The CEA was in the fully withdrawn position, extending into a sleeved fuel assembly. The CEA vibratory characteristics obtained in this test were used as the bcsis for stress ar.d fatigue analyses of its various components and connections. The criterion applied to the results was a 0.8 cumulative demage factor over a 10 year li fe time . The analyses demonstrated that the criterion was satisfied.

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P00R ORiENAL

. CEA Eicaminations,

,equest: Your,workscope does not commit to7a definite number of CEA examinations ,,

.nor does it conmit to spec"ific tests. Provide your comparisons with similar tests at CCilPP-1 and other facilities and reference the specific

" document (s) and section(s) of the referenced document (s) from whicn the

f. similar data was obtained. If this infoimation has not been previously provided to flRC, it must be provided.

Response: CEA, examinations were conducted at Millstone II, Calvert Cliffs I and St. Lucie I during the spring of 1979. CEA's from Millstone II,

' -q frcm St.- Lucie I were eddy current from Calvert Cliffs I and

- sd tested after one cycle of operation in . sleeved fuel assemblies. In . ,

N l addition,,r JCEA'swerevisuallyexaminedbyperiscopeatMillstone II and s ]- CEA's were visually examined by TV at Calvert Cliffs I.

The results of these ex minations are described below.

I. lddy Current Examinations A. _

Millstone II E0C-2 Examination ,

c' '

( )CEAswereeddycurrenttestedduringtheMillstoneII EOC shutdowntodetect(

These CEAs operated at essentially the "all-rods-out" (AR0) position for Cycle 2. This operating mode corresponds tn approximately 15 in. of CEA insertion into the fuel assembly. TheCEAsin,spected;eddycurrenttest[, l and corresponding,. j

.}bservedare

, presented in Table 2. Theindicationswerelocated[

I n histogram of the obt.erved sig~ nal an:plitudes s

is sho, in Figure 1. Atotalof(j. indications were observed.-

on the(] ringers tested, ranging frcm slightly greater than

.qi45 iM'

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of the fingers tested in one CEA e - - L /e showed indicationsoneach,( apart. These -

between Cycles 1 and 2.

- a 3

The average indication is m s J with a standard edeviation of ) The average indication corresponds tc s L

- wear over 90" or less than 2 mils over a greater circumferential

~,V extent.. The maximum signal is 2.7 voits, which corresponds to a e range of values from less than 5 mils wear tapered over 90' to

[

.- This correlation assumes that(

oftheCEAfinger.( jwouldaddtothesignalamplitude, leadingtosome( No ECT signal

]oftheactualwear.

indication associated with was observed.

B) Calvert Cliffs I EOC3 Examination .

i c- 9

,CEAs were eddy current tested, durino the Calvert Cliffs

~ s -

1 E0C3 shutdown;, to detect

]TheseCEAsoperatedatessentially "all-rods-out" (AR0)'* position for Cycle 3. This operating mode corresponds to approximately 16 in of CEA insertion into the fuel assembly. TheCEAsinspected,eddycurrenttest{ )and corresponding ) observed,arepresented in Table 4. Theindicationswerelocatedapproximatelyatf A histogram of the observed signal amplitudes is shown in Figure 2. The )indicationsobservedwereprobably due to

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• Beginning in January 'I978 the Glvert Clif fs 1 CEA programming sequencewas_>modifiedby{

, 1145 107

The average indication is

- , )'with a standard. deviation of The average indication corresponds to .

s ~

1,,

.)Thiscorrelationassumesthatthe

.theCEAfinger.( }.vouldaddtothesignal amplitude,leadingtosome( of the actual wear.

110 ECT signal indication associated with j was observed.

m C) St. Lucie I b

I( JCEA's were eddy current tested during the St.1.ucie E0C-2 shutdown. The indications observed are comparable in size and location to those observed at Millstone 11 and Calvert Cliffs 1.

D) Effect of .

3 00

Eddy Current Signals N /

/* y 1

i f

N _

o

q

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11. Visual Examination A) Millstone II

,CEAs(q j were visually examined by periscope during the Millstone II EOC-1 and EOC-2 shutdowns. A detailed

. examination of the was performed at both

( J examinations. The results of these examinations are presented C

(

g k e

S e

\ \45 \C9:

' 0) Calvert Cliffs I .

Ine r s CEA's that were tested by eddy current during the .

CalvertbyCliffs examined T.V.  ! E,0C-3 shutdown (see Table 4) were als ..

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Ill. _ Conclusions Based on both poolside examinations and out-of-pile flow test simulation, it appears that CEA{

Thiswouldindicatethatthe[

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f n e

0

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24 -

Table 1 e < .

. liillstonc-II, E0C-2 Eddy Current Sienal Correlation for' CEA lest Standards .

Hear Simulations I*

' )

/

Standard

+

Standard [Deviah]on M

4

1145 111.

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Table) jlllistone-IIEOC-2CEAFingerj~

(Eddy Current Results

.c Jiaximum istar.ce Above CEA in Cycle 2 CEA -

30fCEA

})

Humber Assembly _ Bank ((

] -J ' --

'/,

i 5 ] .

e

. l e

D l

I .

80 e

e e

e 4

g  %

en N 1145 112

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Table .2- (continued) ,

!!illstone-II EOC-2.'CLA Fingei(

s s I ddy Current Results -

j ,

11aximum Distance Above CEA In Cycle 2 CEA ]' ( Jof CEA 7

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{(GaePeak)(W llumber As's embl y Bank -

f.

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e 4

a. .

= * * = = ...-.m .

au$ #

e g  %

en 1145 113 i

e

. Table.3-

. ., Cal ert Cliffs I, E0C-3 ECT Signal Correlation for CEA Test Standard s -

, ~.

. W Standard ]

(earSimulation )

Calvert (T1ffs T e ,

5 E

a l

,N

- l i

a i

, *% e 1145 114 1

4

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Table 4

• Calvert Cliffql EOC-3 CEA Finger (

~

. ) Eddy Current Results CEA In Cycle 3 CEA taxirnum "

fiumber' Assembly i(tance Above Bank 7 Vf CEA' (th.)

. J <

m. .

( .

3

~

\

9

-y 4

e i

d o

,q

)

\\h5 \\S

Table 4 (. Cont'd.)

Calvert Cliffs-I E0C-3 CEA Finget( -

Eddy. Current Results

/ ,

CEA In Cycle 3 CEA Jiaximum 1 stance Above ilumber Assembly Bank I

~ ]ofCEA(14.) ,.

. . ~

N ,- _.

/

. s .

1145 116

. 1 30 -

e a

c

$'i g

r O

4

• 4 M

J U) 5:

d Ln .

s w:

g 1- e 3

J A

d>

(I C

0

• )

h'.

c l

e 1145 117

\ \

., I H-E 4

=5 E

J m

• O to U

U to L 0

3 4 ~$

5 0

cc r

9 ss f$

J-5 7.

O 5

1145 118 I

J

e I ,

t t. . .

. e, Figure 1 MILLSTONE 11 EOC - II HISTOGRAM OF INDICATIONS DETECTED DURING CEA FINGEfT ECT IB)SPECTION APRIL 1979 i

N a

M

~

U"1 eamme

.