ML20084G981
| ML20084G981 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 04/20/1983 |
| From: | Liaw B Office of Nuclear Reactor Regulation |
| To: | Benaroya V Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20079G498 | List:
|
| References | |
| FOIA-83-243, FOIA-83-A-18 NUDOCS 8304270219 | |
| Download: ML20084G981 (7) | |
Text
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3 d APR 2 0 1983 4.
Docket No. 50-289
~
- r MEMORANDUM FOR:
Victor Benarcya, Chief Chemical Engineering Branch M
Division of. Engineering
.:2
. XW%M...,.:6 F a
FROM:
S.. D. LiawP hhief L '
.7 1 *L O.
c Materials Engineering Branch,J: >
i
.% [,.%:;29%i2 4+,..:.s<D.1v t:25 01 vision of Engineering. -
SUBJECT:
TMI-1 5ERtFOR RESTART.$U8 SEQUENT TO ONCE.THROUGH-STEAM
, "9 n
0.1
- GEMERATOR-(+OTSG).. REPAIRS?, J#sG;y%y,p;,. $,.4ye,. w- :c y 'e a,
e -.-
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9-Qt.y: sr*1
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As requested, theilnservice: Ins
., ?q' Branch, Division ef:Engineairl' pection-Section'.of1the
, Spy
~
y t800:Rev fAssessmentlef<lfM1-1? Plant Safety for Return.te service?Afte'r'Staise! ~ -
' 'nepatr"ydated March 2s t,'
W P
_1983, and supplementa14tidfefjpsinformetJen#relst ni'toiedecurrent' develope
'y
@e$9$@r3"0T$6sstses. gens'reteri tubes %78
^-> s ment and eddy current;testi
.the'Dit
' 2,
.s MM.'i.,
2 The attached safety'evolusti report $skiresses.15ect'lon 2'E!0T58 Examination y
to Determine Extent of Dogradation".:.asfro(sested W.C.NPcCracken;'semorandum'.M
~ lwas. M d M R y e
' preposeg/
Mist /,WWF$N,p' dated March 3.:1983;iiniwhi Wi'g %
r V-i, we have concluded thetitG@s:.
d.i.iWMF l
- inserest, lopeAafiid qualified.. " ~
' 7.t l
for inspection of;the:0T$t.;
og'demonstfeted fatt1Jty(to7teliably'. detect, t
were pfesent,inithe' tubing.
T The 100% tube inspectionEpreiveh,v3thelsefectpthe(liandjstaking;offeritical w1thah1ghdegree'of.sensitt i
tkveTtee'pluggiaig defective tubes give.ressonabh.' assurance-that. defective tulies,have beens
.frest sg:yicelles:that',ttw.p)lant say. sa identifiedforrepatr[or ~
ser J5f[w*@A%w)AW.dS am.., x return to service.WIGy g n
'~$
i m~ :wy. e; -c., w;.....s
- g.,, m...,. m. m
- 3... m... --
- ne proposed baseline-edty-currentTexaminattensefathe. tubing prior to -
restart and the proposed ed(y current exantnations-efter 90 ful,1,pouer
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Contact:
I.. Frank X-28974 XA Copy Has Been Sent to PDR q w /w7a?I9 W
3 n-.
m :. ' pr 1
APR 2 u' u"c3 Victor Benaroya
-2 days of operation are satisfactory; howe'ver, as a precautionary measure during this period of operation the technical specification leakage limit of 1.0 gpe per steam generator should be amended to include a verified leakage limit of 0.5 gpa above background from any one steam generator.
Our Safety Evaluation Report is attached.
/
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- 8. D. Liaw, Chief
. Materials Engineering Branch Division of Engineering -
Attachment:
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R. Vollmer 9. ; 9. "..
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ATTACHMENT l
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'TMI-l - SER FOR RESTART SUBSEQUENT
~
TO ONCE-THROUGH STEAM GENERATOR (OTSG) REPAIRS J h y.M. "
2 a
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' ' INSERVICE INSPECTION SECTION4 MATERIALS ENGINEERING BRANCH
.lOIVISION0F. ENGINEERING-d,
- ,. ~ -
. g e u..-
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' REF:
CONRAD MCCRACKEN MEMD DATED' MARCH 8, 1983 4;;.
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INTRODUCTION.
i: &. % h % L.::..'t>;;.~41&-k. M.O.
C H :
W.'n.
E' wt "> W
..v.
.. We
.h6w
.4.c-j5%** N.:jLG Q,}.h,y:c,s C'.. M P%.):.P'1%:li;% :. 2. [* :,c' 4 4,Y.L l.
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- U ~
. ~. < > *
- iM In response'.to thel.'$-Q :l ',Q1.W Q'A :.s'p'[ 'g;. :
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e.,
tp subject. menorendus' requestina' input to the.TMI-1 Restart N. g.c-w m. ; pup ig
~~
- Air, s
- m.-:m w..e
~
-e..nnh
- SER we have,p m,
.q#the-f.,11. m n r g d.- c w.,g" Y~~m g;g:.p.,y,,,i; addressing Section s xW
' * ' 2.3 ".Once.Thr;o,upLstaan "3 w.
- M.inife.
tien.
> %s& q'W M w e e. ~...-:'. M.
n-:, '
n,-: w q m + n s A
s Determine.Extentof.Degrada.g:7q 3.e-%.m
.. '.v 5M t
~
51, ~r e
( :.4
.g.s.
i p
a-1.' ti ca"M.p re,:
% port DOSE p '.99.<
1'Re 97 The. bas
?
iwas.
!wei-
..m. M.
W
'Retura.h,A T wF. ? ~:h i
5
>n a.y A.
p wrc
~
.s.m e.v/.1'y :.&to Servi. w..ecemb.,er?
' j /n ?c 2 -- datedli sy' 1
Re...u 2 g'
f gr
.m a. 3:2. <
.7 n
efin.
jm. e w ' gd,ornation.
..,f ce
'Repet s p.s e{m m'A
<rgy':
Caner -.--:-
jag'
- g-m mm m.ra a
a w W @m.
JE.1
. J. e.W,Q
- e relat ng to Mt
$:tt :9u:stn*MQ 1 -
Nc.R -Q W h &.m s.5 ~s iet
~~
dge'providedO&;.WW!1 i, steam, generator.s ue y
N. m6.>.w -. -.,qmq.isi te@y y
- ng. ep.~.9@W
. input:' based 'st, v D.dg..
i ew 1 ficatiest gad:
M epwwMb?r. ;:
- - r e w a d ginspection progree resu..qltL~.
U,,,y
- q r
r i
ces Attachment'No,5 O ' @
W'e
' g,3fdj%ww. %n5G%
t-i.('Q M
~44www$y'w n @3 j
i mpw u
n asem u
&..n ut c
g @ @ p; g. m
- w~0ISCUSSIon g vn
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.ig g.
y y
- .44plQ.^,;* %pFf yQ
. yR. G. 3 e
9 k~
n 4...wm
. a.
- w;.
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Once-Throuch' Steam z. d.-
To, wine' h
d Nk sp, h.5' k*
h
- f. Y M. f & M w
~
of Degradation; m
g c k"'?5y Q f..
e'
- -g Q k ? ~
f jn'
., h 6, q 5
R w <~
g-1 MtE 't.510' f ach t. ",% ';w stial eddy-c netj
. _ C +d -
. v' i,o f.
c
- pw:eny :
.e wM c.sw
.. detects ~were on M-f meter standard diff ' ~
6el.,peebe' f a
,#m;w w w o w e :- A w.<>y c:..
~~s O. n.c
?+ mye the inside diameter ef.
M,b$th'steeSl d?
s;wert C T
.G.
.w v.a.um a
sw in; w*': ;;w... - W.da distributed both ad:.m,:.w.grddia{1y};wy y..ste8Fghtere%8rsSi.ilbe.,
+
ally and:r majority of the defect indications were3n',the upp;er tnhA+h,. m(UTS) togien,.
. =....
..w e ;.
em
.. m.wy.
%y
.., n.os.. m.:m.w -
' ~
eet
,u..
%,.l tube.' roll, transition '2cnefy,...
'..:. n '.
a
\\,
and particularly confined to wxWM,, n%.v.q'5%M., *y 4 y n_ Mi Qs.
.p
,..p.. a.
a
(
p-c c q
N, - we,.ve xy.s n..wrs 4p.
3
- c....
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7[', #
C.
f
$ i. 'T g..d'.%. ', ;sQ
+
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{,
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- y
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.-i.
tw'-~-
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-- = ~ '
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.,. 4 e m. y. p a ; p s m y
,3 L'
r;
- In order to better quantify and characterize the defects it became necessary h
to establish an extensive testing program whereby:special ed<ty-current testing
./
(ECT). techniques were developed so that a more accurate picture of the extent
, wl
' of damage could be evolved.
'W
-l'W
.- r
- n _ ; p: 0 L. y,;
- .m ;E.
L,.
,_. Y '; m u
Using machined notches and l.aboratory grown cracks 'as standards for calibration -
.5 - m' yw-7, 1
..w. w -
r.; w..
- .. - r and comparing field data to laboratory ECT and metallurgical.;examinationsiof L s,. >i
,y
.~.7.:,.g. ay
. ~..
tubes removed from service,.a... s. -
y$
-; :..,%.e..urrent syste.pwes. developed for'100K full-+
n ed c
s
.. g,y.,4;;.
s ge.. ew
. g.. g, -
length inspection of the inservice tube's in both' steam generato.a 3_rs;r.y e g d3 i k & 'h % &v s$ h.akkh&y,&. &hla-u.,;.,.,.. -ki&hph,&W.'h:;.
- .. 3
- . y.
~
.u a
i
~
'3 v
ing f JJj F The eddy-current systan;wh.ich svgived freshn. c. v y w ro u m.v. m ','z s.. m' program,wea a standa
^diamete.r Mith an.g.,ffective.3.p"+ ;w..np.,J:. n
' gain;of'approxi c g differential probe'of.0.54G+f
- m mix. te.b:W:. gr1.i,1f b
...:.w.v m<. gut-y
- n.n. usa.~m
~
and an; mately.60..,Two base frequenc
'IGtt andl200:
mymywm. oise.< '%p%
m.3:
, m f.r.r 9 e
ueaw aladw.;p.m,qi m:,omme rand n
enhance dete.ct on.o 10 defectssand eff 9
g:.gA s,
~ _.m u a.w ywm.
.are used..T.+he.tast ng progras' y m m. - -
.:.y tha,0.540 nc W U M g q red y@me
. ~., ~: y.. +
.q..y.xm u.s diameter standarti.d(are.entfale etter6 v.h ffer ga chlceraskise.4MF,J.(ys% ga T.a_pu
% 24 v.ty ma w
...as sensitive.as"the' absolute
'f T L tWkh Q
' " N % g / M w p& %
- 5. f LV'
- w$4h.f.%gggd1
.v p.
9
,,5
=
eg.sy,re w,laclih
. mw eg
' espection'- u d M
-Results of. inspections ~..
tifthe.
y
.s t
- w
- e. qA4 p.3 -
system (i.my,.ege,_.., e ;&. w;gaigprobe y.
q,{es:.
$ } y.,., M a i it er;;.0.540 e
. 9 Q. m'gney3Q.P'
.a m.
x i:.
s,
- these previouslyf..g.ent)fi gtgr fd 1s.pg%Mp
. yy a.o aw n: m 4
ysg g e
N
. growf( wes.
r.
i bet N th b! N N,ofd significant; pattern terve
.k Y
~'n'ch/ I l
QRQ. g..
- m.3.w.eam 2,
4 if.eua %.9_1 t-4 I
high gain inspect 1
- ;.~.w'
- @Q;s
. a s
.,.:. y}.MG.Y :.W* 'Cl W' m :.
^
.C 2p.
- W. % 4f.pBt%}y N
i 0
m v
f~'
.. e tha i,,ndications in h y-current tesO neasurements l
g e
>:f. w e s s.s -
M.s.y;y 4
y m.a m.g w r upper t.ubesheet; transition fegt sta.
ari TO L wWWaWthanM". ',.
n
~nw :1 -
+u a n through-h11 Ana bence;were%nJyan stcharacterfred' m weM.:m ve tubess. Jetal : 4 N
.,-M 3
w.. m.n w.,wp. w w w.m.w
.. y s
J lurgical examinat, ion of': tubes &removedTtros M.icecconfirmed the-fact'.that.u; 3:
u7 :.
the flaws in the transition zone {regicsA ar.ceeded,501 m.m%
m;mc.
pw,e r.e r.
o-throu
- 4 the majo'rity 1005 th M 1T M D '
N
~Y v
d.g%
y.; j. :
+.
c..
%. ', r,
.C;1/..
., 4.* - "c - - 3
,,..g
- .'d k.f '-
', J [.% ;g
/c{, i. v.
.)
3 a4 s
y l*
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m-
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e 1
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w-T--'-
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. Based on the eddy-current results indicating the depth of the defects, and
[
..the extent of the_ observed degradation ~'it was decided that all unplugged
/
.c
..m t
tubes wou)d be kinetical'ly expanded within the tubesheeti to establish a fM new primary system pressure boundary below the~ defect area..
A
$ A_ 9. & $ l ';z.;.l; h.$. e : % : :. m
' 4?
.y;
.n
.s.,
- +
After[ineticexpansioned$. current..,ex,aminations.usinga,n8:x'1'atisolute
..p l
J
- e,a probe rev'ealed 9 tubes-efL151 examined..i,a n.steas
- gene;rator Atand'6stubes
,.e w r.:
w m.n,.a.
, m,,...
p
- .g I
~;n n,.u. : w W : w. ndications< :~
.w..a ~
n.:
Q,,
7
' of 284 examin~ d in steam generator t.';:w:itU.u.~x.cm..wnot seen by the 0.540 e
. 3.m standard differen'tial. probe.,;y;lberscope examination of.lthe;.gy.. -now ed@ currefit'.
af sep y :;. ww.wa.yz..
m; a
n q-E w
i
.c m.+s,we.4% -
. e:w;wmn.ew w." %f N'se.. i '
- -. m.m.w yewsn t.
ws9ey
- ch3 ere below the ns
- D Y M. A *
-a
. indications,revealedises11 1 and' scratches?
etmte,.wu - n T. Y. 7. -
were.noticonsidered.oof, 5
rential w tivl ef;
~
u,40:'s met after the.90 :::- ap'.,
. o wsze.g%. %.
s 4 n & W m.v 2.. u. y _. Ma geg-m w
,n ;g
. 3
'.,*n n e.
Sasafe :
getifi j
m
.k.x
.v. s.,-~ w w.,w g
- 1 ;
v v ;f we s:.
y" w$Myy &% 27 1
lusion.
e a&%.. :sw wqd.9
.are.
g F
i
- f.. - -
mmm. A manp; ;3.
o n c: A SL acceptab1-s i
era t
.cn;f.4, region 4.p:. M3Mp%p.;
r.
e.1.. :. g
.m l
d[.
$ e# T Si UMhkf i
.acIndes f.n%
exp 4 I e
. : 72:
w
,,w.
e ;,;
up g
w& f, m.h,,
8Is.
i e:u 29,L Q Q Q
~
' ' 'al v'.
i Tjejx
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' Tt - s
- e3.;,p n.
w.<
p a
v,: :
- m. 2
. p'
-~
c-
~*-
.. y WM I: 1 e w xOh 9.$i.._ lfrom;s.m y:p:;g.Wg e
. ;;;;y% m,
\\
u,,.,2 2.: gram.*
l
- pro eu 7 w
n m ~ y~:.f y 3m ntions...c
- 7. t,.9,,d.% -etc :,,1 E T L.
9<
r.
y, l
u.
~~
- %gg",
"rg j
wpweng p.g n
I "Ifrem service lby,p1' y. 'A;;q. %
r*.
~.c sw. n y
plugqed tubes'wors'alsejt 2 01 a.e
?. '. oMy 3j@4.m *. :' q.g z.,. 5. i iffi
~
).iM i
,. h..
r'e purpose of tube-(
i'o{Qff,"J St
- % W
? >g')y,y.,,$.?
,c
", ': -W of tube defte
%m:? -'
w;,;a.ro ?w. l%
vibrationresElt1.,.' Cc1... v.
Dwhich are inW,g?;.
M
.m e ~.2 % wm e;
-(,
to adjacent tubes'orq.creati
.pa ww.
the. area' of high steam, cross flow-(16. u. en yecu gy.n v.e), ers s,,112ed,te.
f14thfJ1
?.3
. span w
.: w.- s: m,,.
ow p #,.b:K Jg;.+. :
tube support plate.; w' 4,..
fpp
.y+-
t c.c :..e
..,ff-
.v
".W.h 4%.;.
W Q.
J..
., M.3
- %,WQV, % & N
- ~ - -
- . W p [ W + %. M. #.f E e.nii.4 %,.
.m:n n g a,.,
f '.
,9
'.x;.3 9.-
guir; ',,
=,,
i e. R ' ; *:9 r
- 14.
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Fracture mocht.nics analysis of circumferential tube defects has been conducted
- ' and it was determined that circunferential defects less than 40% through-wall
...o
~
are acceptable in that they would not propagate during normal operation or
~
accident condit, ions.
9 y
,O r-
...e.'e?m,
- ).
.; ',.1>
i c,
..+ ?
,.a.,,.-
Approximately 66 tubes with ECT indications between 20-401 through-wall as
.. 2 u.
~.'.. u.
,~
verified by an 8XI absolute. probe and located 16"rbelow,the. primary. '
, surface of the-upper.tubeshee;c'ere considered / degraded:tubest 'These tubes - '
. n;wr.. c..
-wsv
........; m......
t m m. -u.w w.. w.m.. s
.ec
,p.
s em ~..
will be l. eft,-in se.rvice-and annitoredJo,w.an extended ISI ' program.
The -
~.
n m, m.,... m y m.s. m n w ;,3.; m..u m., v.
- ~.
-e 9 + n. g e, p c qg. m,thq 4GE and less 1005 reinspectionsof rogram.will fac extended.ISI p n wf.n; a t.a m.;
.:.. :. =
..e. m n through-wallitadjca 1
< as:
separat'a'subsett ioxaminatic E.
4.
x.
- .;m n.. n..~....
e,J4-a., w:,n!show+4ne'.:x u.-m.,+ p-ng.w w c, u:
e w. growth 11n the tal nsHoat
.E cra. g $..n outages. 1 these-p.ca. OTubes. p m : w,s,.
.k,pr,op;agation;?,M
- s -
myv.a,y.,ing;psign.
.a
,,n :
c-e
.v.2 show wn fm.,
igbeJ1 eft'ii cks
~:;n.
,, w ymm g f</.'.iig:.gik,.Arili ha' p.,. -
<. men.
rvi ya rentj,and ep%geriteria,.y La,..ck of..,. ;
.< v n o
.thsk the.mW. Jm' mechanism.fs: w
'.?.h G
- A(ve addimw.'
ucs h;.M@L u p.pefa. W m.
- ion-
- W F1 as ct
- h'q.6 @-a g.y.cx.s..-,. ;@%'.
y c
7i 1
s~(
{;.
u r
4 A '@. 4..arrestad:
me,d A M3.. A
.7. i.s,.6
% $..s m.o
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t h> 4%
- ) h',. k N r tW Y
p 5'
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CONCLUSIONS i
We have concluded that the eddy-current techniques developed and qualified for j
inspection of the OTSG tubing demonstrated the ability to reliably detect, with j
a high degree of sensitivity, the defects that were present in the tubing.
j The 100% tube inspection, preventive tube plugging and staking of critical defective tubes give reasonable assurance that defective tubes have been identified for repair or removal from service, so that the plant may safely
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return to service.
The proposed baseline-eddy-current examinations of the t'ubing prior to restart and the proposed eddy-current examinations af ter 90 full power
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days of operation are satisfactory; however, as a precautionary measure during this period of operation the technical specification leakage limit l
of 1.0 gpa per steam generator should be' amended to include a verified leakage limit of 0.5 gpa above background from any one steam Generator.
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