ML20134K752
| ML20134K752 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 02/12/1997 |
| From: | Jacob Zimmerman NRC (Affiliation Not Assigned) |
| To: | NRC (Affiliation Not Assigned) |
| References | |
| NUDOCS 9702140218 | |
| Download: ML20134K752 (52) | |
Text
-. _. ,_
February 12, 1997 LICENSEE: Southern Nuclear Operating Company, Inc.
FACILITY: Farley Nuclear Plant, Units I and 2
SUBJECT:
MEETING
SUMMARY
- DIRECT TUBE REPAIR METHOD OF STEAM GENERATOR REPAIR AND PROPOSED TECHNICAL SPECIFICATION AMENDMENT REQUEST SUBMITTAL SCHEDULE
Reference:
Meeting Notice by J. I. Zimmerman, January 27, 1997 On February 5, 1997, the staff met with Southern Nuclear Operatin3 Company, Inc. (SNC), and Westinghouse Electric Corporation for initial discussion of SNC's plans and schedule for submitting a proposed Technical Specification amendment request regarding the use of Direct Tube Repair in the repair of steam generator tubes. Enclosure I is a list of the meeting participants. Enclosure 2 is a copy of the material presented by SNC and discussed during the meeting.
Original signed by:
Jacob I. Zimmerman, Project Manager l i
Project Directorate II-2 Division of Reactor Projects - I/II l Office of Nuclear Reactor Regulation i Docket Nos. 50-348 and 50-364
Enclosures:
- 1. List of participants i
- 2. Material presented cc w/encls: See next page E-Mail Hard Copy '
FMiraglia/AThadani JZimmerman GTracy, ED0 Docket File RZimmerman LBerry EMerschoff, RII PUBLIC /
SVarga Dross (SAM) PSkinner, RII PD 11-2 Rdg. /
JZwolinski ESullivan OGC GHornseth JTsao ACRS PRush CBeardslee /p HBerkow RHermann d T O/
.140031 To receive a copy of this document, indicate in the box: "C" = copy without attachment / enclosure "E" = Copy with attaghment/ enclosure "N" = No copy 0FFICE PM:PDIlr2 lC LA:PDIIf2\ 11 D:#0tFE l NAME JZH9sE41RAN:cn LBERRY V(h) HBER4W DATE A/ff /97 R / W h/9V 3 /h /97 / /97 / /97 / /97 JOCUMENT NAME: G:\FARLEY\DIR. SUM 0FFICIAL RECORD COPY
- M"'t88 a 8188 P
L NRC IRE CENTER COPY l PDR
l 1
po uru ,
p 4 UNITED STATES s" g NUCLEAR REGULATORY COMMISSION t WASHINGTON, D.C. 206SIM001 i k.....,/ February 12, 1997 l LICENSEE: Southern Nuclear Operating Company, Inc.
FACILITY: Farley Nuclear Plant, Units 1 and 2
SUBJECT:
MEETING SUMARY - DIRECT TUBE REPAIR METHOD OF STEAM GENERATOR REPAIR AND PROPOSED TECHNICAL SPECIFICATION AMENDMENT REQUEST SUBMITTAL SCHEDULE
Reference:
Meeting Notice by J. I. Zimmerman, January 27, 1997 On February 5,1997, the staff met with Southern Nuclear Operating ,
Company, Inc. (SNC), and Westinghouse Electric Corporation for initial
~
discussion of SNC's plans and schedule for submitting a proposed Technical Specification amendment request regarding the use of Direct Tube Repair in the
~
repair of steam generator tubes. Enclosure 1 is a list of the meeting participants. Enclosure 2 is a copy of the material presented by SNC and l discussed during the meeting.
wU acob I. Zimmerman, Project Manager Project Directorate 11-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket Nos. 50-348 and 50-364
Enclosures:
- 1. List of participants
- 2. Material presented cc w/encis: See next page l
5 I Southern Nuclear Operating Joseph M. Farley Nuclear Plant Company, Inc.
i cc:
Mr. R. D. Hill, Jr.
General Manager -
Southern Nuclear Operating Company t Post Office Box 470 Ashford, Alabama 36312 Mr. Mark Ajiuni, Licensing Manager Southern Nuclear Operating Company Post Office Box 1295
- Birmingham, Alabama 35201-1295 Mr. M. Stanford Blanton Balch and Bingham Law Firm Post Office Box 306 1710 Sixth Avenue North Birmingham, Alabama 35201 Mr. J. D. Woodard Executive Vice President Southern Nuclear Operating Company Post Office Box 1295 ,
Birmingham, Alabama 35201 State Health Officer Alabama Department of Public Health 434 Monroe Street Montgomery, Alabama 36130-1701 Chairman !
Houston County Commission .
Post Office Box 6406 Dothan, Alabama 36302 1 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 1 101 Marietta Street, NW., Suite 2900 i Atlanta, Georgia 30323 Resident Inspector U.S. Nuclear Regulatory Commission 7388 N. State Highway 95 Columbia, Alabama 36319 Mr. D. N. Morey Vice President - Farley Project Southern Nuclear Operating Company Post Office Box 1295 Birmingham, Alabama 35201-1295
f I LIST OF PARTICIPANTS MEETING ON FARLEY DIRECT TUBE REPAIR OF STEAM GENERATORS ONE WHITE FLINT NORTH. 0-1-F-5 FEBRUARY 5. 1997 NAng Oraanization Jacob Zimmerman NRC Edmund Sullivan NRC Geoff Hornseth NRC Phil Rush NRC
, John Tsao NRC ,
Cheryl Beardslee NRC Robert Hermann NRC John Garlington SNC Mark Aj1 uni SNC Brad Moore SNC
. Rick Mullins SNC Bala Nair Westinghouse Gary Pierini Westinghouse i
Bill Cullen Westinghouse Boyd Padford Baltimore Gas & Electric Jeffrey Poehler Baltimore Gas & Electric Lynn Connor *** Doc-Search Associates i
4 Enclosure 1 l
i i
! Direct Tube Repair 4
i
! of ,
j 4
Steam Generator Tubes i
l I
1 l NRC Staff / Southern Nuclear l Meeting l
l i
i 4
- Wednesday, February 5,1997
- One White Flint North Rockville, MD f
Enclosure 2 s
. - , _ . , , . - - . ~ . - , . . . _
L l Agenda Introduction
! John Garlington, SNC l Why direct tube repair?
l Brad Moore, SNC i
DTR Process / Corrosion Process Bala Nair, West j Structural Evaluation j Bill Cullen, West l
l NDE Concept l Gary Pierini, West
! Schedule I
! Mark Ajiuni, SNC '
l l
Discussion - All l !
(.
Why direct tube repair l DTR)?
e Inability to repair flaws
- above sleeves l = Efficient use of resources i
! Potentially quicker Less complicated l
l Reduced radiation exposure
. Less impact Heat transfer Flow resistance .
. s l
l LASER WELDED DIRECT TUBE REPAIR WPF2685 49/0203971
s 4
@ Objectives of the Direct Tube Repair Program
- Restore the structural integrity of degraded tubing which exceed the repair criteria Slow or stop the progression of active degradation i
I i
, .I t i !
l l i
/
. ~ _
)
nde i
ot _
gle _
ep _
Rm Ro _
TC Dy l _
l r _
ei a _
l a I st aa r }
g LP(
i n l) '
S :::
s _
mmg
- ~
s _
a ; '
.o a e r
! e o n I B
P r
o r e
s t i n
s R rb 3$ a T L
a :
1 g- D _
W
)
- '. k J t
n _
es ms pe I l
i a
ndo gr ai d
en g _
o c ige r
l o -
OeR D ar vP a s
- D u oneo f
e b
s ug c to 7 f mT d d
u e
o u 7 f a
r g
F A rD l e l
as f l )
a i
t s vI i
n a 3
- iP 7, 3
o 2
d c en a
g } do ai D
rg ge eR 4
s e
s 2
w
b DTR - Filler Insert Approach .
4
[
n Alloy 600 Tub g : 4 3
2"
, +
}
Alloy 672 InseV .
l!
lE ,
d werms 4swom-4
g Focus in 1994 Was On a Process That Modifisd Weld Chemistry Through Addition of Filler Metal
. Filler metal-based process using consumable insert developed l . Parent tube penetration limited to about 35 percent,
- with 0.020 inch buildup l
. Corrosion tests yielded excellent results
. Tensile and burst tests showed no significant difference from virgin tubes
. Good low and high cycle fatigue test results t
I a
WPF2685 49020397-5
! @ Schematic of Filler Wire Feed DTR Process -
1 FILLER WIRE FEED e
,[ L'
- e s . ,
4,
- Original ; ,
I Laser DTR Region l' ,
(Partially Completed)
Degraded (. ,
J Region Laser Beam I
i b) DTRIn Progress WPF2685 49/020397-7
J7R 3R CESS .
t l
1.00' LENGTH 0.020' _
OF REPAIR BUILD UP i a TSP 0.75" THK ,
l y
i O.030' TO 0.040' MELTED REGION OF - -
i PARENT TUBE WALL i
_. A l
t i
2-#.m,-.-.~_.--,.._.--_-...--_..am.4 m._,--+- .---- --- - - - - - - ---- - - - .------;
1 i n a
1 l
1 1
I i
i 1
I
{ C o
O W
W M % ' .: '
A sTAlGim9p$$yiN i 3, &'
, m o te$@h[p@fIIR,$w iM
- e y; . c nk.
e u , ..
I j
1 u)) s... .j,+J . 5 2
y.
j "Q '.Q , 's -.t[.T "y
? .,.
1 m y .. %} ;.,
i G -
M'
?.
l Sf ' ' , ' .. :hb i
,p,9k #;'
, . w , ~.
j ,'
',).!. .
$ *'y, n .
- ,~ #f?
- a c :r.,,..:.,,
.. ,.3 i (. ., ; .. - ; g"s" a ,. >c-
- i. -p , ,a: p ,
. [\ ,
[ g : -
.:~;;.m$[
f .i ;
ik [,, .,, .
N '
,' ' l m < -+iA c 4d. err %
'g'A
.; . lt f- 4,@
y gg / -
,- ,.3 >
' b.
C'/h .,
e-t @
e- .
l M
s amme 9 l
i v
\
1 l l I l I .- . . - -. - . _ . . . - . ._ ._
I!;:i l,I, Ii:!!!,it,! f:;;ll,ij l!jII I R
T .
_ D d .
_ e s ,, , ,
- a ..
B r.~ .o . . e.
_ e r E
. i .
- E .
W -
E r -
R e t l -
l i
e F s )s
_ f . 3 (m M .
o D
- 4 I
e b
4 uT -
S mor
_ t s -
R ec f
s _
i m
e
- q. .
E a DI n
t N
n e
_ h =
C 0
_ d .
e r
o -
u " = - - .=* %
0 3
y1% % 0 0 s ' ,
_ a _tgi; e
. Md l s e 9-AW 7
9 3
0 2
D W
9 4
5 8
-. 6
. w- 2 F
P W
- .i. , 4 ; i < i1 ! , i4!!1 -
b Summary of DTR Weld Microprobe Chemistry ,
Analysis Alloy 600 DTR Insert DTR Wire Feed ;
Alloy Alloy Elem. Ht Ht 672 Ht Ht HT Ht 690 8161 7368 8161 7368 8161 7368 Ni 76.17 76.21 55.81 66.11 65.35 70.2 69.7 58.00 Cr 15.59 14.87 43.11 29.19 29.97 23.4 24.0 27.31 Fe 7.62 7.98 0.23 4.12 4.11 5.7 5.7 7.11 Ti 0.59 0.58 0.57 0.6 0.5 i
b i
i WPF2685 49420397-10
b e
! @ Post Weld Stress Relief Heat Treatment Qualified .
. for DTR Process is Same as for Laser '
Welded Sleeving
. Range of 1250 F to 1600 F for 5 minutes
. Target temperature of 1400 F i
WPF2685.49020397-11
l g Comprehensive Accelerated Corrosion Testing Performed with Two Heats of Alloy 600 MA Tubing
. Heats known to have high susceptibility to SCC
. Five different types of DTR specimens Pre-degraded tubes EDM notched specimens Thinned tubes Pre-dented tubes (TSP simulation with packed crevice)
Base tubes
. Control specimens Pre-degraded tubes without DTR for OD exposure tests Roll transitions for ID exposure tests
. DTR specimens stress relieved by heat treatment WPF2685 49920397-12 I
g
~
Accelerated Corrosion Testing was Performsd with -
- Both Doped Steam and Caustic Environments -
. ID and OD doped steam tests at 750 F,100 PPM .
concentration
- OD caustic testing at 662 F,10 percent NaOH solution !
. Non-fixed DTR specimens (no axial stress)
. Fixed-fixed DTR specimens (thermally induced axial
! stress maintained during corrosion testing)
WPF2685:49520397-13 i
r
< e , .
p;. ;,,. .<-
r, . f . . .. .:,,. p .! J;.A
- v. p e ,*.,.?"v*f.*. M.. **' --
l
- st p_. .. . g..-^. . . . --
m , . 2"c,. .*l*,,,,,,.g.. ,
- ) '\ * ,-
. . ** N., f,,,
.4
. ~ . *23,..<
- ra ,m.,.
~
u
~
, . + 3 7.*'.,** .',' ' '> l ;.; .'../ .', ~.
s.:
- .L.. ?, Y,*. . ,-5;.,- .gW
, ;,.,- .n....... .e
.. .* - -/ o. -
., .,;r, -;, , **.
- .* j'"w m.. *-
),
. .f. '.*:2: .T . . . . - . - .." '. , .~.: . .).,&. .._',.r.
.Q..
a g ,
- ' y 5.,.', . . ,, .~
- 5*
l ',; * .& ,. 'Ll_
-*~'
y, l * "* :< ;* .,,a.-.
.g. ' ', , Q:.! * ' ;
'2
- e. .
.- .~.p-X'=*h%X:?
- - - n 1rz 1 ;.. r gh; . c. .
~. .<.. -.L.. : ~.'. .,,.-%.'.Ma-n ..
~. ... -
. . . , -..; s- - . c.
a . .,
g i
-f-+, ;
z .- .,.? . ~.--- - -
3; !.<
-w j
g/ /g/ _JJ r --y-qq. .
. a-" . " \
- p, - -
3
- . 2, ..1-
- f. - y.W,, ,
. s
. . . '....y + .. ~..-~ 9. ,.
f;' S ',t'; *
'. . , - ,- ;)^, *l .b
.f .. e-
~: .:
.u-Y.
a
, e'"
- f. .
g.
-~
..,. .- .~ ., w..s..~.;,. .,.
a.>;,.:. n
.. ,., . .' :. ,,. .. '; o.7e+: ..; .y' ,:.;; e
.t
~.:-i;..a.. : :. . . .
. y,.,...~- w' -s.-. . *,*.
q s" .: . *. . ..a. . ~ . . - .
1 1
i 907 Hours in Caustic Tests Environment; l
- Specimen No. 530 l
)
! ,.i~s..hf,sf..4W.i; ss ; w .: m m ~ .. . .. ,.
i a
>. g n.c -
+- ,, a
- m
- . 5%': .v.v 1 -
a w, y".+ n s'"A" ' (R%'&;,3 y.: .W.,..
4an+eeA,... . r.4.'.,
c . , . - . .
'. -' . . . , ev.
t.
.7,y/.+%c qr ,4; -W..
p :. 3 r W.y'hn.c : %~.. e.,.h.3W
. x g. a. . ;z w .m..r
- .,4.g ,;.
w-
, . . .c.a
~ ,1 . . >'.; ....m: .
- -+ e. ..n s... ost ;u -
p:
.. /; c*. W -.4.m .". ,t.'.* L;t.a.:-.,3
=.3 n m 7ed .},'^~T m; 1
-y.["- / , , M..,gy j ,
g*
1 e ww. .. . ."n.
w- .a . %. t . . ,,, m4.
1 W.-r W..:. . .- ;? ~ y, %; . > -
> 3 'mef
R&*. *--^$ l * .
3
,s . ^'f.
. . . . .;. - 3.;g3 * $b**g"e.,* ., f $* ' ' ' . , . " . .
l . 'w -
d 1
4 l
j ff $Is i 923 Hours in Doped Steam Environment; i Specimen No. 507 OD C,orrosion Crack Terminating at DTR Weld i
d J WPF2685 49/02039714 1
g Corrosion Test Results Support Life Expsctation for DTR Process l
l l
! . ID doped steam test data shows repair life 10 to 15 times that of roll transitions
. OD doped steam and caustic test data project even ,
l better performance ,
l
. DTR life estimated to be in excess of 20 years i
WPF2685.4WO20397-15 ;
g Tensila Tests Sh@ wad That Propertiss of DTR -
Weld Metal Exceed ASME Code Allowables <
RT RT 600 deg F 600 deg F Yield Ultimate Yield Ultimate Strength Strength Strength Strength (ksi) (ksi) (ksi) (ksi)
Base Tube Metal
~
Ht.7368 65.2 104.8 55.8 98.3 Ht.8161 46.4 106.7 43.1 96.6 DTR Weld Metal Ht.7368 56.4 105.3 47.7 86.8 Ht.8161 52.0 100.9 44.3 83.6 ASM Code Requirement = 35 ksi Yield,80 ksi Ultimate @ 600 F l
i l .
l WPF2685 49/02039716
g Burst Properties of DTR Weldsd Tubing Are Approx-imately Equivalent To Those Of As-Received Tubing ROOM TEMPERATURE PROPERTIES 9 Tubing Burst Tube Burst Press.
Base Tubes A129 7368 0.8742 0.7699 11.65 0.0522 91.7 N/A A130 7368 0.8742 0.7699 11.72 0.0522 92.3 N/A B131 8161 0.8764 0.7769 11.35 0.0498 94.2 N/A B132 8161 0.8764 l 0.7700 11.42 0.0532 88.4 N/A Freespan DTR Welds 610 7368 0.8069 0.7370 10.00 0.0350 110.3 1400 611 7368 0.8065 0.7309 10.80 0.0378 .109.8 1300 l
613 8161 0.8068 0.7420 8.81 0.0324 105.3 1300 615 8161' O.8074 0.7340 10.14 0.0367 106.5 1300 l
Clamped DTR Welds 556 8161 0.8037 0.7620 11.35 0.0389 111.6 1200 1 557 8161 0.8025 0.7290 11.07 0.0367 115.5 1200 558 8161 0.8054 0.7260 11.51 0.0397 111.0 1200 l 560 8161 0.8052 0.7230 11.80 0.0411 109.7 1100
~
WPF2685:49020397-17
- _ _ . _ _ - . - - - - ._ _ _ _ _ _ - - - __. __ _ --- - _ .__ _ ___--____ __._- ____ N
h Filler Based DTR Fatigue Tests .
. Low cycle fatigue tests Alloy 600 MA and DTR tubes Room temperature
- Strain controlled, strain rate of 0.0001/sec i
. High cycle fatigue tests Cyclic rate of 20 Hz Room temperature i Half sinusoidal cycle stress wave form (0 to max stress) 8 Runout for 10 cycles without failure l
--s_,,.,.
t
w Low Cycle Fatigue Test Results .
s s ---
ASME Best s
Fit
' x .
ASME Design at X ,,
Curve A
} - ,
& Alloy 600
}
-s
.Qw Am l Das or lkm% , ,
a h;g - . .. ,
5 Alloy 600 J __
N -. , Tube 0.1 X DTR Tube i
l l -
0 01 1.E+2 1.E+3 1 E.4 1E 8 1.E 4 1.E+7 1.E.8 Cyctu WPF2685 4902039719
b ASME BPVC Section XI Code Case Inquiry was ,
Approved by Main Committee in 1996
. Reviewed by various Working Groups, Sub-Groups, i
and Sub-Committees in December
. Approved by Main Committee
. Confirmed by letter ballot with no negative votes ll 0
@ Supplementary Testing and Qualifications Planned ,
for This Year
- . Weld process testing with prototype wire feed weld head
. Accelerated doped steam PWSCC tests under approximately 100 percent preload locked tube conditions
- ASME Code weld process qualification 4
. EPRI Appendix H qualification of NDE process i
i i
WPF2685.41WO20397-21
t 6 a e;
e d
E N !
9 m
DTR StructuralIntegrity j Evaluation i .
ei W. K. Cullen !!
8 Westinghouse NSD jja; prepared by: A. L. Thurman Westinghouse NSD j
.j Introduction !I sl E
u a
u Provide analyticaljustification for DTR repaired tubes in 44 and 51 S/G's gl
- Bounding set of generic load conditions I a Summary jj
- Strength properties adjusted based on tests !!
e
- Meets ASME Code requirements ll aPrimary stresses 8!
a Primary + secondary stress intensity range ,!
eFatigue !
_____ ___ . . . - . . . . . . . .--_--.-.-.-..O
- -1 i Assumed Degradation Profile !
s u
E m Axial cracks for entire non-welded DTR g:
region length l m Non-welded tube wall in DTR region Il assumed to have zero structural strength j m Pressure boundary at DTR region lj e
hi e
?
k[
s i
Finite Element Model !!
2 E
5 9
m 2-D axisymmetric g!
a:
m Symmetric about center of weld Rl m Degraded tube properties behind weld !:
- Zero strength (wall thinning) $l
- Zero hoop strength (axial cracks) !
- Results approximately the same for both cases nl l
l
?
kl 5
l I
e e
.\
DTR Weld Metal Properties )
e .
2 ,
m Alloy 690 mechanical and thermal properties g:
a Alloy 600 MA yield strength appropriate a:
1 m DTR ultimate strength reduced I
- 3 ,
! - Data points for 600F at low end of Alloy 600 Ig distribution (but greater than Code minimum i!
values) ll a
- Performed statistical analysis
?
i
- .. ---. . A
1 . .
l l DTR Weld Metal Properties (cont) l l t e
2 i m S m= lesser of 2/3 yield or 1/3 ultimate !!
m ASME design fatigue curve with allowable a!
R cycles reduced based on fatigue test results ll e Maximum stress concentration factors j:
applied based on geometry ll e
. $l B;
o
ASME Code evaluation
~
s' s:
N 2
m Primary stress evaluations g 8
0 Condition Calculated / Allowable Design 0.66 i Faulted Upset 0.53 0.65 l:
g; Test 0.90 l!
. a 8
1 e
- ASME Code evaluation (cont.) ;
M m Maximum range ofprimary plus secondary !
stress intensity 0.59 of allowable !
m Maximum fatigue usage 0.72 I e
d i
s 8
E l
Minimum wall thickness l l:
8 E
s ASME Code pressure stress equation gl m TPS proximity, unwelded tube material l neglected i; e Limiting tmio determined from Normal l' conditions il 8
- P i=2250, P o=720; AP=1530 psi l
- P m<Su/3; tmin=0.0267 in. e m Upset and accident conditions resulted in ;
lower. calculated minimum thickness
Summary ;'
s E
' E s ASME Code limits are satisfied gi a:
m Minimum required wall thickness for R:
plugging limit determination - 0.0267 in.
ll
- Conservative based on in-situ conditions ll m DTR weld structurally acceptable ll e
. $I g1 l
I =
s 8
ep Af
/% hkm e;
^
Direct Tube Repair Non-Destructive Evaluation Presentation to the NRC 5 February 1997 Westinghouse Electric Corporation Nuclear Services Division
t=,
,; > 4:
./ gyf g
+ Program Objectives
+ Current Work
+ Eddy Current Techniques
+ Qualification Program
+ Proposed Eddy Current Technique
+ Summary 4
- -- - ~
+
[k '
'?$kovam Objectives w :q <
+ Pre-Service Process Acceptance Verify Location and Extent of Repair Detect Unacceptable Process Anomalies Verify Presence of Heat Treatment Verify Sound WallThickness
+ In-Service Inspection Detection of Unacceptable Crack Penetration
+ Growth of Remnant Crack
+ Presence of New Repairable Indications
. .--. , , , . . 4 -, , . ~ _ _ . . _ _ _ , . _ . . . - .,.___m__._ _ _ _ _ _ _ _ _ _ _ ___._ .__. . ._ - _ - .._.._ , . _ . - __ ,_ _ _ , _ __ . - . _ ____ _ _ _ _ __ _ . _ _ _ _ _ __
,/'
. Pro pam Objectives (cont.)
+ Present Section XI Requirements for S/G Tubes
- Volumetric Examination with UT or ECT (IWB-2500)
- Re-Examinations Same As Original
- ECT Method Capable of Finding 20% Thru Wall Indication (Section V, Article 8, Appendix II)
Acceptance Criteria:
+ 40% Thru Wall OD Flaw (IWB-3521), or
+ Analysis of Other Flaw Types / Sizes (IWB-3630) i o
O
/\
~
Pro ; am Objectives (cont.)
+ Code Case Requirements UT
+ Minimum Total Thickness, 10%
+ Minimum Deposit Axial Length
+ Lack of Fusion (2 0.125 inch in width or length)
+ Volumetric Examination of LBW Deposit Per Modified NB-2552 (Reference notches 20% thru wall)
_ _ _ _ _ _ _ __ _ _ . - _ _ _ _ . _ . _ _ _ . _ _ . _ _ . _ _ _ _ . _ _ _ . _ _ _ . _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ ___.__m_ _ _ m
.y -
- y Pro ' m Objectives (cont.)
+ Code Case Requirements (cont.)
ECT
+ Amended IWB-3521: OD Indications in the LBW Deposit of
$; 20% of Original Tube Wall Are Acceptable (Reference notches in deposit used as a comparitor)
+ Alternate Acceptance Per IWB-3132 May Be Established
+ Detection of Existing Parent Tube Defect or Support Plate to Verify Location of LBW Deposit
+ Qualification ofTechnique ShallInclude Flawed Samples
- 4. .
~ /C pnt Work + UT of Clad Tubes Demonstrated Capability to Find:
Lack of Fusion < 0.125 inch in Diameter ,
- Thickness Within 10%
Axial 0.010 inch Deep Notch, ID and OD ; Circumferential 0.010 inch Deep Notch, ID and OD Location of Original Flaw in LBW Deposit
+ ECT of Clad Tubes Demonstrated Capability to Find:
Location of Original Flaw or Structure (Lower frequencies) Acceptance of Repair Possible By Adjusting Frequency Such That Rejectable Conditions (i.e. Insufficient LBW Deposit Thickness) Are Detectable Flaw (0.029 Inch Deep From OD - 18% Penetration Into Repair) Within 0.050 inch LBW Deposit Detectable i
j %, - ' Eh& Current Techniques
+ Different Eddy Current Methods for Different Applications
- Bobbin for H/T Presence, Detection of Some Anomalies and Repair Location and Extent
- Rotating Coil for Verification of Adequate Repair Penetration and Unacceptable Anomalies Cecco-5 for Verification of Adequate Repair Penetration and Unacceptable Anomalies
.g x -
Quah)ication Program
+ Designed in Accordance with EPRI ISI Guideline, Appendix H Assure Detection of Unacceptable Condition
- Statistical Basis - 80% POD at 90% Confidence Depth Sizing - 25% RMSE
+ Process Verification Qualification
+ Sample Design Process Samples Degraded Samples
- Simulations l
[ Prohysed Eddy Current Technique 9
- Based Upon Structural Requirements
.:- Challenges -
- Surface Condition Makes Depth Sizing Difficult NDE Error / Repeatability Acceptable But Detectable Remnant Indications
.:. Ease of Interpretation
'Go/No-Go' Test for Most Repairs Based Upon Frequency Gating Amplitude Based Acceptance of Remnant Indications
O Q
'/Pro ' sed Eddy Current Technique (cont.)
- - EDM Sample n .3 = ra, m
.,,3,. ., 3 ,.
1, . n
;7 ,7-ma .
- ".= , m .i, im,
..._",s" ;" "L'!. ..l1... .r. i .. .i i,i ii.
>- tm., n. i m. is .
",l"'"
, h peisstel I tasunt setto ..is low e trata
. . . . oc. . e
- +:
C +-= =f 0.040 inch deep from OD 0.030 inch deep from OD Q x; \ g ste o se o.es i l .
e e%
- ld'Prohpsed Eddy Current Technique (cont.)
+ Crack Sample 713
,, .,, .,, n.n . > n. m =>
f e--~ , 2 TO:,,, ;; M
H""'*"
i i ... '- ";""" J i ...,,,
.. '3
.. . .ro 3....q i i, i
- we = www Hr1 terriv, g " ' * "
, p. , . i smo ..it i r e list, t i v- 2.2. ocs e e.
i ! _._ d f f ::. . - ^% L 7 7 I 0.029 inch deep from OD STD J. j < x .
'Q 4. 3.
. 4.
, k..
f . Projpsed Eddy Current Technique (cont.)
+ Concept of Amplitude Based Acceptance Concept of Remnant Acceptance 20 18 16 14 12 g 10 5* 6 4
- ~ ~ ~ - ' - - - - ~ ~ ~ ~ ~
2 0 0 10 20 30 40 50 60 70 Sound Wall (mils) _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ . _ . _ _ _ _ _ _ - _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _. . *w*
- V' t'
i
- ..(b?piary Su
+ DTR Inspectability by UT and Eddy Current is Feasible + Depth Sizing of Remnant Flaws Difficult + Possible to Use Threshold of Detection to Determine Acceptability + Qualification of Eddy Current Technique - Will Meet EPRI Appendix H Criteria for Detection + Detectable Remnants May Be Left In Service - Criteria Must Be Established and Verified
). ... i-5
- Schedule
! March 1997 - Technical l specification amendment ,
! submittal to NRC ' i ! June 1997 - Eddy current l l qualification report j submittal to NRC j June 1997 - Corrosion I Qualification Report-PWSCC
- submittal to NRC i
l March 1998 - Implement in Farley Unit 2 outage l October 1998 - Implement in Farley Unit 1 outage l l
.}}