ML20084P951

Preliminary Rept on Meeting Concerning Nine Mile Point Core Spray Nozzles & Related Piping Sys

ML20084P951
Person / Time
Site:	Nine Mile Point
Issue date:	05/06/1970
From:	Gilliland R PARAMETER, INC.
To:	US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML19289B377	List: ML20084P627 ML20084P712 ML20084P719 ML20084P726 ML20084P905 ML20084P951 ML20084P959
References
DC-65A, NUDOCS 8306130081
Download: ML20084P951 (8)

Text

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Paga 1 c:_ L h A Preliminary Report cn a : ceting Ccncerninc ue : lina :.ile Point Core 1

1 Spray '!ozzles and Related Pioing '

Systees - !:ay 1,1970 Tepcrt ?:o. CC-55A Isay 6, 1970

? _ cad fcr- /EC Centrac: ;c. AT(ii-1) - 1658

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.' aranter :.c.69-70A; Subcentract l'o. 7

. . red by :  ?.. G. Cilliland Assistant Professor of !<aterials Engineering University of Misconsin-Mihtaukae Milwaukee, Wisconsin 53201 Precared through:

• Paraceter, Inc. '

Ccnsultir.g Engineers Ela Grove, Wisconsin 8306130081 711028 PDR ADOCK 05000220 p PDR -

Page 2 of Report No. DC-65A Ci s tribution Copics I AEC Regulatorv Orcanization Division of Comniiance Technical Prcgrams - Washington (2)

J L. Kornbl itn , D. Pomeroy, H. R. Canton, J. W. Collins Inspection rnd Enforcement - Washington (1)

R. h. Engclken AEC Contracts Division Chicago Cperations Office (1) r.. N. Viller, E. Halcan Parama:er, Inc. (1)

R. C. Gilliland (1) i C

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f Page 3 of S Report No. DC-55A In trcductio_n At tne rectast of the Divisicn of Cc.;ciiance, Washington, the author 2r.unded a raatinc at the USAEC Pnillips Cuilding in Bethesda, Maryland cn - ay 1, 1970. This caeting U s scheduled for the purpose of reviewing t a current status of the icaking West Cora Spray Gozzle (N6B) in the Nine m Point Raactor syster, operated by the Niagara Fchawk Pcwer Corporaticn, Sy,;;use, New York. Those attendinc this cacting included representativas f c. GE-;?ED, particularly Dolf Huboard and representatives frce the Niagara

ch s.l., uti'.i;y, in additicn to USAEC-Page'.atory Personnel. The specific arcas covered were the follcuing:

1. Tne CE-APED catallurgical analysis of the caterial failure in the subject West Core Spray I;ozzle (NCB)

2. A review cf the other furnaca sensitized stainless steel parts in tne syster

3. The proposed rathod cf repair of the two (East and West) Core Spray Ncazles, and their current crogress

4. A revic.. c? the details ralated to a piping system strass analysis bcir.g ptcforr:d by Teledyne Faterial P.esearch, Waltham, Mass.

5. A review of the USAEC-Ccr.pliance retallurgical analysis cf the East Cera Spray Nozzle (i.!5A)

C. A caview cf the prelirir.ary results of the GE-APED tetallurgical analysis of the East Ccre Spray Nozzle (NSA).

Discussicn

• The folicring is an acccunting of the information obtained by tne author from the discussicns of varicus pecple in attendance at the May 1,1970 tec ti ng. No attempt is cade here to fully analyze the ccmcents cbtained.

The ccorents and recorTandaticns unich are ccnsidered appropriate will be given after sufficient time allows a thorough analysis of the situaticn and will take the form of a subsecuent report.

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r Peport No. CC-GCA Page 4 of 8 llllll lllll)

Mr. : . . Prc t, Vicc Presidac; anL Executive Engincer, .:.7C opened the ating in _ hcif cf the licensce. The :c.Olete metalbrgical caalysis of the

. a t Core Spray ::o::lc (L6C) conducted b./ Cancral Electric was presentec to the crcup in the form of an LMPC docurunt cntitled "Peacter Pricary Systen Investi-utica et Nine Mile Poir.t Nuclear Staticn," dated May 1,1970. Inis document se, ercedas and replaces the "Prelinirary Report Core Spray Nozzle Safe End Nine

'ile Pcin: Pcwer Station" dated Jarch 27, 1970.

- In additicn, this report con-

ains the '.MPC/CE pcsition as to cause cf the cracking, catallurgical analysis of the remaining piping syster, strcss analysis of the piping system, cnd the prcpcstd rathod cf repair (Itats 1-4, abcVe). The auther is currently in the prccess of t'orcughly reviewir.g this report.

Curing the uriefing given by the Niagara l'chawk and GE people the folicw-inc points were rade:

- , , 1. T. c Gi r;;allcrran',ic s ,m tudyo'srevealed that the tyr.c 304 stainless steel Cracking was seen sace cad tr.~ _.:r . s ic;va lare rully sensiti:cd.

accur in Oc;i. :no safc cnd ar.c the therral sleeve in an intercranular 7 00.

2. Cnemicai analysis of the metals did r.o: reveal any abnormalitics : .c.: eve r ,

,c s - caalysis of :nc cxica covering the pipe / sleeve internal surfacas did

. o ,eT2 indicate the netsuca cf fluorica.

3. T.;c Toledync stress ar.alysis of the sub.icct nozzle, piping system, and aangar system revealed the stress near the failure to be approximately E0,CCO psi. In ger.eral, it was stated that these studies showed icngi-tudinal stresses of 45,000 psi and 22,000 psi on the West (K60) and East (NEA) Core Soray "ozzle, respectively. This stress analysis indi- y cated U:e piping syster to be g ncrally underhung. ,

Mr. Ccif Hubbard bricfly revie:cd the progress of the totallurgical studies currently being rarformed en the non-leaking, East Core Spray "czzle (56A). To date these stuaies cnly incluce investigations of the surface of this piping section. T-ese stucies have die folicwing preliminary results:

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Page 5 cf C h N Pepcrt No. DC-65A

1. In t.: [c;.nui;r cracks ucra fcund in the thir.ned are; cf 'the safe end I.'. 'rcn the 12-to 6-o' clock positions (12 o'cicck is straight up).

2. ldciticr.al I.D. , intergranular crachs were foundin the uicker sections of the safe end, scociJicclly in the 12-to 3-o'cicck pcsi tions.

3. It was stated :nat this ciu t as ;bcut one-half full cf t :ter uhtn cut, cua thcuch this pipe section had never been used to pass water to Ine reactor syster.

4. I; las stated by CL t ;.c.c oxice ccating en the I.D. cf this Ecst c :le was differen; th; . fnat e .ich was found in the West "ozzle.

5. ~ .2 East Nc:zle safc end C.C. shcuad indicaticns at the i-to 3-o'cicck r.d 6-o' cicck pcsi tior.s . Sera cf those indicaticns appeared to be te;.nsgranular i n r.ature.

The ;;C-Ccmpliance section ucs given a sample of this East "o::le to study. T..cse investicaticas ucre conducted by W. J. Collir.s, Technical Sup-csr: Srr.;a - AEC Ccmpliance. The ?.EC sample was cut longitudinally along Ic. 3 pipe axis betucan :n 10:20-li:30-c' clock positions and contained abcut 1 .. cf t!.c pipe, thc fielc welc, about 2 in. of the thermal sleeve, and about 4 in) '

y the safe end. Tne follcuir.c is a brief statement of the findings of this ir vastigation.

, 1. Tne safe end was cbserved metallographically to be fully sensitized

.-S W cad ccat'ined/numrcus cross /transeranular cracks.

2. Tca therral sleeve contained nutarcus transaranular cracks but did not exaibit a sensitized ticrostructure. ., u s // * :

3.u.-,

Thee.:e pipn Te section exhibited a partiall.y en rs: o<rus sensitized microstructure,lbut'

-O PMcracks ucre cbservedf The nicrcstructure of the o fte.>

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o. JL',djacen,saJuield u; ew.

cv w ucid shcued a spheroidized 6-ferrite phase 1

. indicating that this ueid had received some degree cf thermal Ch^" This was furtner nw r~a va'cM r ~1" supported by the appearancc of a recrystallized / grain grcuth nicro-structure on the 0.D. of the safe cnd about 1 in, from the field ucid fusien line, cutside the heat-affected zone.

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r s Paca 6 cf 3 lllllI llIllI P. aport f:o. CC-CEA

4. IiiC :.:cfral sicaVC exJ.it ;;:c a Ci cros tructure Ci' t i nir 'cctetriC-sh; d ce;cipi tat:s. 'n cluctren . nicroprc, analr. of th ne pr_ci?itatas reva:Ic.d thcm ta ca exc: dingly rich in tit _;iua. 1: 2 ir.for ;tien yielcad the ccnclusior. :.12: these precipitates ucre a t :r. . carbcnitrice :nd that this tearmal siccva caterial mich to n:51321 ratarial instcac cf AISI 304 stainless steel.

5. f;c 'es .;2ra taken of the residue found on the I.D. of the AEC-East

!::::10 specitan for chemical analysis. A sarplc was orepared from this r:sidue cy extruding electrocas, using graphite as a binder, to alicu an ar.alysis using nass spectrographic techniques. Cased cn the a surpdon that this rcsicua was essentially Fe 02 3 (supported!y a ccm-parisca with a standard using a scanning electron microscopc} the analysis results revealed approximatcly 13 ppa of chlorine. It was stated that tiis analysis was believed to be ccnservative, considering the necessary cethod cf ;nal;cis.

• 0 infor: c. tic.. 't:s &;.icat cy ,:'.?C/CE rarsonnel pertainini to the ma _.-

luni cal ansiy;;a cain car =cr1ad cn the 3E 9crtion of die East :.czzie. '.

.erald Car.t;c. , Te chnicci S;;;;r: 3 ranch-/IC Ccmpliance, did prcvida the fci-s 'c." infcrcatica concernir.; this investigation, as providad by an AEC cn-si .e

" - a ctor, "r. U ldi s Fc:cpcy;.

'. Ear.sitized matarial w;s fcund in tne safe end.

. Tr.rae (3) intergr;nular cracks werc fcund 1/4 in. long and 1/4 in.

C frcr the field uelt rect en the I.D. of the safe end. The cracks were ali cr.ed axially.

3. !'atil ca_ ra.nhi c sectioni na. ic:t cr.e crack but this analysis revealed the re..wininc tvo cracks :c ba 0.090 and 0.040 in. Icng.

The !TC/CE persor.nel cavict.0d the planr.ed repairs for replacing the re-Eci.. cora spray nozzle. Thcsa statacants cra briefly presented belcu.

i. The 'last nozzle is praser.:iy being repaired usino Type 304L stainless steel catarial and incora rating slight redesigns to the thermal sleeve

f

eg og liecort No. CC-65A Papa 7 of S and c rica :ystem. Tc.e .'2::sipntc .c.erra slceve nc. orovidas a drain syste :1rcach the attac?.nn t weld ;o recuca the pcs; ,ility of static ccndi ti ons . The redesi[r of the piping system entaii ne use of coru 6 in. piping tc reduce the : ress situation existi in the pra-vicus design.

2. A n:/.. hancar sy:^2m fcr the ccra spray no: les has been casigned and i r.s tali;d.

2. Ultrascnic testinc of all cine welds uo to the vessel wall is being pcrforced.

4. Similar repairs are being ir.itiated ca the East nozzle.

5. It is proncsed that ultrascnic and pcr.etrant inspections be perforrad ir i year cn cli furnace sensitized material still existing in the system.

C. Prior to current reactor start-uc it is proposed that tests be perforced (ui:n Taiedyne assisting) which indicate that proper expansicn tolerance can ce raintained. Furthcr, it is procesed that similar testing be per-fcer2d af ter each cool-dcun.

2.t a crivate r;ating between AEC and GE personnel discussions wara heiJ cccc:.rning the optitur repair rathed for furnace sensitized stainless steel safe end raterials in many BHR reactor systers. GE related the results of their rataarch cn stainless steel raterial. These investigations incl'uded welds, anncaled caterial, and sensitized raterial and essentially revealed that sensi;ized raterial will fail preraturaly (18-20 hr. vs. over 400 hr.) when -c Lniaxially stressed to 125% of yield in envircnrants of air / chlorine atmosphere (rec.. temperature to ISO F) or pure uater plus 100 ppm oxygen (550 F). If the ta-terial is sensitizedit fails in abcat tuo (2) hours. Other discussions centered around the advantages and/or disadvantages of overlaying and whether this is an r al or be:: r repair rathed to a cceplete changeout, or replacement, of non-c a.si ti zed ce te ri al . No clear-cut conclusion was fcund to these ouestions',

l al-2.cuch the r ; air of Oyster Crack should provide scra sound background en cycriay repair rathods.

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Para 8 or. S Report !!o. DC-65A Ccnclusicr; ine puncse cf this raport v.;s to atter pt to asser51e the .ajor facts cutlined anc discussed ct the Cy 1,1970 maeting at /EC Cecpliance Head-cu a r:2rs .  !: ccaclusion till be s:cted until a comolete state. rent of the rJsu::s of t .2 ccny investiccticas cca be cb :.ined and reviewed.

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