ML020810317

Meeting Agenda, to Discuss the Licensees Reactor Pressure Vessel Head Penetration Nozzle Inspection Plans

ML020810317
Person / Time
Site:	Millstone
Issue date:	03/12/2002
From:	NRC/NRR/DLPM
To:
References
TAC MB2639
Download: ML020810317 (28)

Text

Overvicir

- Steve Scacc SitimnarY of'Respolise Clark Maxson hielitstrY Eyerience Clark Maxson NDE Method.s

- Mlkc Stark NDE Equipment Dan Schladcr (F77)

ContingencY PlansllRA Yehl'a Khalil I'lltilre Phills Steve scace Conclusions

- Alan Price IcCV

DNChas.1011ovved the allov 000 cracking problem hi

1997, peýlo'oned a

100(/(

ECTInspection o/'/]()-,7./e.v Visual Inspection

(ý/, /he Millstone 2 penetrations is impraclical due to the insulation coll.liguratioll.

I)INCintelids to peij(')rm an NDE inspection ofthe Millstone 2 head pelICII-(ItiO17S.

MCinspections will result in an i.n1lovati

.ve, aggressi

.ve, and comprehensive data set.

Atstarlupfil-om 2RI4 there it-ill be assurance that the MP2 head i rill meet all regidotor.v and peiftwmance reqn1remelits.

2 002r

Ranked 29th In the NUSCeptibilitY out of'09 PWRN CE de.vi,(,)1ied andfi'ibricaied head using Huntington A/loYs pelletratioll Ilfbcs.

Penelrotion.s do not comain thermal sleeves Asbeslos insidallon ol'vessel head is conlonred and close to the he(

I(VS illjiice.

3 (93

TYPICAL CEDM NOZZLE

cot,

REACTOR HEAD NOZZLE CONFIGURATION

iINSULATION DETAIL iiiCOG~

Millstone 2

is a

CENSSS

- Zero circunitýrenlial cracks have beenftnind lo dale ill non B&

VV NSSS (over OSO noz,'Jes inspected)

CE Fabricated Head with Himlin

-Jes

- Zero leaks have been reportedft')r CEftibricated heads co-1

Current Inspection Status Plnt w

t lff

• t J

• exa l~

¢

• J.flL 71,1 Bulletin 2001-01 B & W Plants Non B & W Plants Category Plant Name Inspected Leaks

%Leaks CircAbove PlantName Inspected Leaks

% Leaks CircAbove Flants < 5 EPPY Oconnee 1 69 1

14%

0 North Anna 1 65 0

0.0%

0 Relavtie to Oconee Oconee 2 69 4

5.8%

1 Robinson 2 69 0

0.0%

0 Oconee 3 69 9

13.0%

3 Sorry 1 69 2

3.1%

0 ANO-1 69 1

1.4%

0 TMI-I 69 5

72%

0

-I Totals =

345 20 5.8%

4 Totals

• 199 2

1.0%

0 lants 5-30 EFPY Turkey 7o777 65 0

0.00%

0 RdativevoOconee CrystalRiver3 69 1

1.4%

1 Farley 1 69 0

0ý00%

0 Farley 2 69 0

0.00%

0 Totals 6 69 1

1.4%

1 Calvert Cliffs 2 8

0 0.00%

0 St. Lucil 2

0 0.00%

0 SONGS3 34 0

000%

0 Bea'er Valley 1 65 0

0.00%

0 Salem 1 78 0

0.00%

0 Kewaunee 40 0

0.00%

0 Prairie Island )

40 0

000%

0 Totals 470 0

000%

Plants >30 EFPY McGuireI 11 0

000%

relative to Oconee Totals -*

11 0

0.00%

0 Totals ý 680 2

0.3%

0 I

J I...................J I

co%

Totals ý 414 21 5.1%

5 eta Icrcks 0

0.3%

Lick oftherinal Sleeves (it MP2 allows access./o'l 111trasOlift,

()It's, that will:

ti-Vitil o"d

circ, I////(, relitial cracks iii the tube.

- Assess the area around the tithe to verýft the s/1-11clitra/ inleorih, o

'the RCSbottlidarv is h7t(ICI be ore a breach would be (let jo ected vistiallY.

Gather additional data jor hiditstr.i to ass ess the susceptibilit),

ofCE designed plants.

9

Ultrasonic cvaillinatioll ofthe nozzlemicces.ýll HN, demonstrated the capabilitY to detect:

- Cia-flawls, in the tube above or beloiv the

ýveld

- Axial f7aits in the tube above or below the weld c'I'law.s over the ailoclunclit wehl

- A-via/flairs over the aitachment wehl 10 CIO

Circumferential Flaw in Tube (Above or Below Weld)

Demonstrated successfully by detecting crack tip in appropriate Oconee Specimen.

Axial Flaw in Tube (Above or Below Weld)

Demonstrated successfully by detecting crack tip in appropriate Oconee Specim en Circumferential Flaw Over Weld (Detection of crack tip in Oconee Specimen in required)

Dem onstrated successfully by detecting crack tip in appropriate Oconee Specimen Over Weld (Detection of crack tip in Oconee Sp ecim en required)

Demonstrated successfully by detecting crack tip in appropriate Oconee Specimen Surface Exam of Attachment Weld (Currently no MRP dem o available)

Weld metal not addressed Flaw Depth Sizing (Currently no MRP demno available)

Flaw sizing not addressed.

Framatome Rotating Ultrasonics CI I Axial FHaw

Meihottý UTol'the Inteije'rence Fit Region

- Demonsirated to Mill.ýIoiie NDE Personnel that dala takeii tit variou.s siles can reliablv defect the leak palh throul(,)h the lmeljýrelicejil region.

lyle abilitY to review this reglon ultrasonically enhances our leak detection capabilities beýbre a

leak

ývould be detected blv a bare head visual examination.

12 c117-

INTERFERENCE FIT HOT TO SCALE

Ae ultrasonic in.spection technique, capturing rellected encrg.v oll compitlerized C-scan dj,ý/?/(I.vs, can accuratelY defect a

leak path emalialing either 11-om the we/d to tube Intei.-Iiice or above the we/d 1111-Olf"17 the 1*1110jercticefil reg

• 1011.

14

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15

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16

F77 chosen bused oil:

(, olltilluous Improvelliellt ill exalllillatioll teclmiqlw increasin'(1, their abilitY to detect till the

./laws aliticipated ill the Ilfbe.

Continuou's improvellielit Ill equipment ellubling odditional dato to he obtained bY 111COMORI/i/I(I) multiple probe rotamil(.,

head design.

Colltilliloirs improvement ill examination lechnique to imesti(i.,ate 111tel-ferencefit regionftv evidence ol'a leak path.

17 615

Ill Progress NDE Development FTI Is con till to make advances ill ultrasonic examillalioll lcclllliqllcý Ilial call assess cracks illiliatilig I'll the weld reglOll.

18

Q-7

clca

.1 r.,

We expect thal our MP2 RPV Head is healthY Our owage plan includes planftw 1001/c voltimetric inspections

ofRPVHP, A

minimifin conlidenceftictor ol'90%

wi//

be attained

,similar to the Steam Generator Tlfbe Inspection StandartL AnY indication ol'PWýCC In anY RPVHP requires completion ofall penetratiOlls.

A RefielfReqtiestjor NRCapproval is beim) prepared to address vve/d repairs

ýfnecessar.V.

21 CAc

Assumes that the (IT inspection has identified no imacceptableflairs In "n

" RPVHPs Calculates the iq)per 90(/(

con

' fidence limit on the nuinber ol'RPVHPv with poten tia l/Y imacceplableflows (is a

'fillictioll of "n

This method is oppropriateft'ff the RPVHP inspection since the popidation sil-e is finite A

random sunipling that is consistent with SG Tube inspection wi//

be emplo.ved 22 oW

Cýzl

where:

r is the number o1'RPVHPs with in OUT' C11Se We require that I- =

0),

72 112 is the normal variale exceeded with probabilitv "12, and P

is the probabilit.l.

offinding a RVHP no'-Je with imacceptableflaws.

Note that Ilie equalion above dolthIc-sided distribillioll.

Since we have afiiiiie population with si,.e N

=

78, we replace

/--' '/' /).v 12

-n)4(N-

1)

Nole:

lor sing/c-sided distribution replace 12

'/1 (N

'12 ith 24 ciz?-

MP2 RPVHP Examination Potentially Uninspected Defects vs Sample Size Number of Penetrations Examined c-fl3 6

5 4?

3 o 2 z

0

Develop a design package)ý)r removable instilation Develop inspeclion plan based on 2002 residts llti'll,-,e doia and lesson.v Icanic(I.11-oin olher utilities il i specl I'M IS.

Participate in indirstrY work on replacements with our olher Dominion planl,ý.

EPRI and Owners Gl'Otlj)S.

26 02'f-

Millsione has been a((Nressive in addressing the AlloY 000 cracking problem.

DNC Intends to Inspect 100(/(

ofthe Millsione

-2 Reactor Vessel Head penetrations in the next rel'ieling outage.

tVe hare demon.strated el

ýýct've techn'ques to detect./laws Contin'tenci, to slop Inspecting w/H onlY be eml)1o.ved iftre aresatislied 1hat our Reactor Vessel Head can be returned ioservice sa,/e'/Y.

27 C-2S

Millton Uni 2

eactr Had Ispetio