ML20084P959
| ML20084P959 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 05/08/1970 |
| From: | Gilliland R WISCONSIN, UNIV. OF, MILWAUKEE, WI |
| To: | Harold Denton US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML19289B377 | List: |
| References | |
| NUDOCS 8306130084 | |
| Download: ML20084P959 (3) | |
Text
The University of Wisconsm - Milwaukee M;LWAU A J. W '.,CONG N G3201
^
CC--.--
- 70 s
.c d R. Danton CE
-.a.nical Support Branch Ut:_a i::ates Atomic Energy Cet=ission 7E ':0rfolk Avance Ea:nes ca, i'.d.
Daar Harold:
Enclosed is one copy of ry pra'.i.ninary report c.'. the Nine Mile.situaticn entitled, 'A Prelimir.ary Raccr. cr. c.':eting Concerning the Nine Mile Point Core Spray Nozzles and E2hte: pipine Systams - May 1, 1970." You will note that tnis is prica;ily an cc::..; cf the ciscussions of this caeting, relat-ing only the specific pcints cucessed and reserving comment until further evalus c ;n has been perforT.s..:y 22.
It is -
cpinion that them era a fca cpen areas which should be coverse be-fore ;
- al evaluaticn ar.a dacisions can be cada en the overall problem of th e s.
. cized safe enas '.n :hin 2. R reactcr systets. The following art. r/
evalu-_ r of these necessary points:
(1) T
. '. lins finding of the existcnce of titanium carbonitrides in the th e rc.c. siceve caterial of the East. ozzie must be ccepletely verified by a totai
'r.istry analysis.
If this cc erial is truly 321, this would be the caly x_ Sie v. y of making such a cafinite statement.
(2).
-.rj opinion that we will need r.uch tore information on the East Hozzic pipe and uald to definitely docum:nt the possibility of field stress relic? es we and particularly Jce Collins suspect.
C (3) I; a? pears to T.a that it is important for us to know the total metallur-gical rindings.: investigated by GE ccncerning their portion of the East Nozzle specican.
'y definite decisions by the AEC Regulatory Section might be very precatura ithout this kind of informaticn. The implication here lies primar -
in the documentation of the extent of transgranular cracking.
Joe Colli r.
_ finitely verified the existence of such mode of cracking, but to cate '. _ :: not k u.! uhether this is widespread or not. This means th t the unkncw
..are is. hctner or not one can expect concentrations of chloride in other ; -tions of the piping system, and tihether or not this will be an envir-cncent ;0 be exo;;ted and contended with in the future. One may consider that a stagnant m..a such as this secticr. was and the fact of a compressed or periodically cc.raressed vapor phase ;.
.licuid phase may play an important part in the overali significance of the
- a cb ained in this-East core spray nozzle at tiine Mil; Point.
8306130084 711028 PDR ADDCK 05000220 P
,2 g
(4) A vary brief c viat. on my cart cf :na ther";l sleeve cacigc. pecvicusly and curr:nCy bei:m tsea in the ccra spray.cazia c;uses concern as to s capabilities of ac;_elly doing its job.
This casiga is not aGecuately orotectir." he thick sec-tien c:.ae pi?e ce the section chang-. This situation could result in large taa rral ;trcsces ;; this racnified thermal discontinuity.
I have taken the liberty to cisce;s thi; uith Dick Lofy, who feels in concert with rce; and in additicn, Joe Colli:a las cerranted that this cculd lend much raaning to the cbservation that c ra ck:.
ana t.c. dad to bc axial, or, after initiating radially, tend to ultitately procar', i n ;r. a > i al manner.
(5) __
f, I 2r s :ill very endaciced as to Ola carits or advantage; or cycrlayir.g s;:
d safe ur.;s a irarove their Overall catallurgical-corrcsicc.-cachanic~.
c 42-i iics.
3c;; ably one cf the tiings th;t cisturbs me the cost is the lack of sigri9 :nt cc cart;ne inferr;;icn in ragard to these characteristics of overlaid s tra - _. :s an; their a0plicatica to thu existing problem.
It has been cbserved
- .a ;.. stair.less staal structuras contain 20% 6-ferrite and scratires greater cc...
ad te exhibi: s rass carr;sica characteristics. Mcuever, cverlaid weld cacc; - cf s::inless staol like 20Cu uill aluays contain less than 10% and usually v-;
za to 5: 6-farri a.
In additicn it is not icprobable to expect occasional en ;-...mj)itized sur acas "hich occur curing the overlay process, allcuing for ens 2 c;,,.., ~. j w
5 c...
~~-
~--.s
.no pc.nts prescc:ad ;bova arsentially ;c.dicata ~ hat I feel is necessary to be learned befcrc _.; r.axt c;f or dacisicns can be c;da. The collection of this in-forrstica cay ecg :re ry travalir.g to Richland, Washingten to inspect the existing s ar.p i _.
.ich c;va provicusly been analyzed or c:.y raquire further analysis.
.21 statarants ara '." hat I fcal may result in future applications. Prcsont The:2 env -
nts c7 nuclaar re c crs may be c?ticum cr, in other words, the best one can -
for, such that c;terials and fabrication cathods may be needed to allcw cc ::::Lility. ith thesa envircnnant: to the extent that integrity is maintained.
Ucra specific;ily, if it is estaal:shed that chlorine can norrally exist in con-c:ntrations of the for:: fcLac by Collins, then type 304 stainless steel which is unsersi tized could not ce an atacua:a caterial in the system. With the present sensitizad 304 it is nct clear uhat is the best technique for repairing this con-citici -cver,.;"inc or rap,iaceman:.
_ina overlaying process may very well indeed be c;
..a adecu;ta frca many standpoints, but one of the materials that has not been considared greatly is a lcu carben type 310 stainless steel, which provides increased clicyina contents with rascc:t to chrcaium and nickel. This caterial,which ray tend to be slightly fissura-sansitive in the wald catal,would not be greatly susceptible to intargranular or transgranular stress corrosion attack, and would provide the necessary strengthening cach=. ism, which One may expect to Icse when die lod carber 334 pre; are used. Tnasa ccr.conts shcuid be considered premature until a little ' 3ra thcucht is givan to them.
In adci icn, I do not believe that one shculd forget the econctics of the situation, and the fact that the.replacecant
r
[*3 M
e of thcsa dafectii. ria:ai y _a ; L :.. a econcrical as their ciadding, particularly we:a cne considsrs ca a in ocmm c c.
- , the nice must be half cut cut of the sys ta i in the fi 1
?! ca.
.ri nally, c.1[h chi. " r.e ccnten
- isi du _
- nd their con-can:mi ons ra.? ' 2 :hr.: :h ugn be c, van t; w.m. alloys which m. ncn-ferrous i'
_t ca, i.e., inc ci cy E00 and Inccnol 6 C.
I hava scan literatere which indi-c c. u -.:st Inrcael 500 is ruda ccra racistan: to chlorine and oxygtn-containing ur "' :. ants
...:c Incoicy C20, but I hava not baan able to verify this with a c_ cs e r searca of the li teratura recently.
I believe it is relevant at this
.1rr ;c r.ention, at least, tha experiences of LACBWR and the fact that their cocc'le tc chantacu t was acccr,lished utilizing Incenel 600.
I fc: '._uat I should c;;c scma verj ariaf ccr: ants as to the stress situa-Iii
- m.. m..n. m s. cn.n..og, o
cru,ct.i n.g c'nd cr= ci.'
a.
c
- s. -
_... v. 1 a e, m..,.; a..-..m..-
.-.s.....-
m
- r.
- icn.
- . s ry belief tc.at tc.;..an: Enc.u'.cr cracking observed cn the East
- c:.
Jasul' ac 'rca the reducum stras; existing c: this location anc the chlorina cto;
. ca t.
1.D. surface.
Cor.varsel, th in:argranular cracking fcund cn the f
.s.
': le ::.id ca considered to be caused by taa high strass conditicn here, of n.
pr _;oly of the yiald strang:n, and the high ccncentratica of oxygaa in
_u eschere arcand this situatice.
I; is ccaforting, I believe, that cos: of
-_:_ ; racks fc;nd in this system and others hcVe not been associated with the act c cnas of walcs anich hava not baan stress ra'.ieved or otherwise
..si c _ d by furnace traatten:. To ca this ir.dicates that field welds do not c; ; large ar.cugh arats cf sansitized catarial to cause concern from a corrosion sing st:ndpoint in th; envircncents axisting in SMR reactors.
In addition c...
sc:a inccat s:udies as to the raside;l stress arcund welds indicate that their
.:agni:L;as ar; :he greatest cac tc.a r;ta of chanca of tagnitudas are the greatest ia the vicinit/ cf tie fusion iir.a anc cta exist either in the heat affected zone siGa of :ne fucica iina or :h;
.a'.d _at;l sid: cf the fusion line. These stresses c;n ca aitner compressive or sansilc, _c.d cca aaproach cnd be almost ecual to the jield s rangtns. Yet in nc ca:: r".a 'te found cracking naar cny fusion line of the waic taich causad trcubla c :na c?ar;; ion of the plant. Inerefore residual stress c;tsas cy welcing and sensi.izatica caused by walding dcas not seem to be a factor cf.. c;nce ra, and the implicc.:icn ". era, frca :.;y standpoint, is that uhether over-1;.
_ is usca as a rapair ca uncd or cc:pleta chanceout is effected, the welding c--.:ica in either of these will not unduly harm the integrity of the piping sy. ;_ ^ ;; repai rad.
~ c;: statacant:
shcen above, are ty current thinking on the subjectof this e
12 :2r and the att:ched raport.
Jhile tney ray scam disjointed and confusing, This caly results frca the indacision and prarsture rc bling which I find myself '
c: 'E a t th is ri ca.
In any event, I hcpc these comments serve your current purpose an
- 'ill solidify ry thcugh
- s in the next few days such that more definite de-cis: _c.; can be arrived at.
.c..
_.. c.. u, l
.. -, ru;s,
r <
.s
.-ze r
s
/l r
,n
./f
/.
.- 3
. ;w
~-
Rt G. Gilliland
-