ML20140H188

Summary of 970417 Meeting W/Westinghouse in Rockville,Md to Discuss Mechanical Model Associated W/Incomplete Rcca Insertion Issue.Meeting Participants Listed in Encl 1

ML20140H188
Person / Time
Issue date:	05/02/1997
From:	Craig C NRC (Affiliation Not Assigned)
To:	Matthews D NRC (Affiliation Not Assigned)
References
PROJECT-700 NUDOCS 9705130002
Download: ML20140H188 (68)

Text

..

4 Mag k

'v UNITED STATES g

s j

NUCLEAR REGULATORY COMMISSION l

• \\....,l*

WASHINGTON, D.C. 20665-0001 I

l May 2. 1997 i

MEMORANDUM T0: David B. Matthews, Chief Generic Issues and Environmental Projects Branch i'

Division of Reactor Program Management Office of Nuclear Reactor Regulation

'Claudia M. Craig, Senior Project Manager d

~

bi FROM:

Generic Issues and Environmental bI t

i-Projects Branch

\\

Division of Reactor Program Management

\\

Office of Nuclear Reactor Regulation

SUMMARY

OF MEETING WITH WESTINGHOUSE TO DISCUSS MECHANICAL MODEL ASSOCIATED WITH THE INCOMPLETE R00 CLUSTER CONTROL

~

ASSEMBLIES (RCCA) INSERTION ISSUE The subject meeting was held at the Nuclear Regulatory Commission (NRC).

offices in Rockville, Maryland on April 17, 1997, between representatives of Westinghouse and the NRC staff. The meeting was held for Westinghouse to r

discuss in detail the additional work performed with the mechania.1 model developed for the incomplete RCCA insertion issue.. Attachment 1 is a list of meeting participants. Most of the meeting was closed to the public due to the proprietary nature of the information being discussed with regard to the mechanical model.

By letter dated April 22, 1997, Westinghouse provided both proprietary and non-proprietary versions 'of the material presented at the meeting. Attachment 2.is a copy'of the non-proprietary version of the presentation material.

Westinghouse provided the results of the sensitivity stu' dies, the drag.

methodology, the predictive methodology, the data related to testing performed with ZIRLO tubes, and the proposed fuel assembly design changes.. Based on the work it has performed, Westinghouse has concluded that no restrictions are needed for burnup, the mechanical model is sufficient ;to predict span. drag, and the methodology is sufficient to determine the potential for incomplete RCCA insertions.

~ '

A member of the Westinghouse Owners Group (WOG) presented the'WOG position on

)

the issue. The presentation material was the same as that presented at the WOG/NRR Senior Management Meeting on April 16, 1997.

The WOG representative's

. presentation material is provided in Attachment 3.

The WOG representative outlined the short, intermediate, and long term actions to address the issue.

I Additionally, the representative informed the staff of the new working group within the WOG that will deal with fuel issues.. In the past the WOG has not bO been involved in fuel issues due to the fact.that different vendors provide-fuel to the WOG members.

But, recent issues have-arisen which laay be conducive to WOG activities.

The representative outlined potential areas where the newly formed working group may be involved.

f & f00 2un

=

D. Matthews May 2, 1997 The staff stated that the validity of the Westinghouse and WOG approach relies entirely on the accuracy of the mechanical model. The staff wants to ensure the mechanical model can predict susceptibility and requested Westinghouse run the model using South Texas data to determine whether the model fits the rod insertion problems at South Texas. Additionally, the staff requested the mechanical model be submitted to the '3ff such that a detailed review can be performed. An additional meeting bett cyn the WOG, Westinghouse, and the staff after the work on the mechanical mode; :: Dsmpleted will be needed to discuss plans for future actions.

Project No. 700 Attachments: As stated cc w/atts:

See next page L

M y 2. 1997 D. Matthews The staff stated that the validity of the Westinghouse and WOG approach relies entirely on the accuracy of the mechanical model. The staff wants to ensure the mechanical model can predict susceptibility and requested Westinghouse run the model using South Texas data to determine whether the model fits the rod insertion problems at South Texas. Additionally, the staff requested the mechanical model be submitted to the staff such that a detailed review can be performed. An additional meeting between the WOG, Westinghouse, and the staff after the work on the mechanical model is completed will be needed to discuss plans for future actions.

Project No. 700 Attachments: As stated cc w/atts:

See next page DISTRIBUTION:

See attached page DOCUMENT NAME:

4_17_97. MIN To receive e copy of this document, Indicate in the boa: *C" = Copy without ettechment/ enclosure

• E' = Copy with attachment / enclosure

• N* = No copy f,3 0FFICE PGEB /ulA SRXB;Bft A)(3/

PGEB:SC /* "

l NAME CCraigi W JLyoW RArchitzel l

DATE 4/'D/97 g/2-/97

.hfd4/97 l

OFFICIAL RECORD COPY

DISTRIBUTION w/atts:

Summary of April 17, 1997, w/ Westinghouse dated May 2, 1997 Hard Copy Central..: File PUBLIC PGEB R/F RArchitzel CCraig ACRS OGC E-Mail SCollins/FMiraglia AThadani RZimmerman TMartin GHolahan BSheron JLyons MChatterton HScott H0rnstein HConrad JRajan FGrubelich l

1

_.__.._.______3

=.

v.

WESTINGHOUSE / NRC MEETING

. MECHANICAL MODEL UPDATE FOR THE INCOMPLETE RCCA INSERTION ISSUE APRIL'I7,.1997 t

MEETING PARTICIPANTS NAME ORGANIZATION Claudia Craig _

NRC/NRR/PGEB John Galembush Westinghouse Nuclear Safety Elwyn - Roberts Westinghouse CNFD i

Jim Sparrow Westinghouse CNFD l

Vinny Esposito Westinghouse CNFD Howard Menke Westinghouse CNFD l

Vance VanderBurg WOG/AEP Muffet Chatterton NRC/NRR/SRXB i

H.F. Conrad NRC/NRR/DE/EMCB H.L. Ornstein NRC/AE00 J. Rajan NRC/NRR/EMEB Harold H. Scott NRC/RES/ DST t

l l

ATTACHMENT 1

Westinghouse Non-Proprietary Class 3 i

l l

l Incomplete RCCA Insertion Program Status i

b i

NRC Meeting i

April 17,1997 1

l

{

msmemustmmmmcuss2 NRC Meeting Inceinplete Rod Insertion 4/17/97 Sensitivity Studies SPARROW l

1 Drag Methodology gg,c MENKE

{

r j

Predictive Methodology MENKE

. % bic i

i i

i ZIRLO Data ROBERTS g> g,> c I

[

f FA Design Changes ESPOSITO f

Near Term Langer Term i

a: w u % ppe i

---

,----im._.

a.

2Ma..

e mem,.

Ms

-e-.ma-se.eeem-.J4.+*wuea.s-4-s_.ohas4 adm_44ha1.eA 4...

_Aw.d4 4%

__a-J.m eit..a._J.M.*E--A h4 hah 4_ AMm.#-.1 a

f e

2 j

=

N N

t j

I

}

l l

l 4

e i

J 1

)

)

l

?

.=

i

5 l

j w

l

. amW l

l

. muW l

M l

M i

o l

00 1

1 I

i 4

i s

.I I

I, i

)

i l

l l

f a

d I

l a

J.

s Bow Sensitivity - Hold Down Force Span 6 I

ap I

t i

k i

i 5

)

I i

l i

f I

W i

i 1

i 3

Bow Sensitivity - Creep Span 6

)

-ahp i

t P

f r

I i

i j

I l

\\

t 4

l 1

I Bow Sensitivity - Fixity

~

Span 6 t

I i

[

l D

i l

I i

e L

k L

I

(

i i

f I

l i

5

Bow Sensitivity - Temperature 3

Span 6 ahp I

i i

I i

r I,

k

?

?

h 1

M b

m l

b 6

t Growth Sensitivity - Hold Down Force i

c@p t

i t

l b

b I

l L

i P

k i

E t

i r

m I

N I

7

au,,a

.ashua e

& A.u4 4 4

..#_ma J

-mm.

-4 y ma4_

a 4..an._.pa,A.maen4m.mW

,.mw+m4w.e sm.-,J*#w_.=%

.ammm 2wa.E4da=_.es haw ayAwww,,,e,es_.mme-mm _m. wegww w4mae, d

e I

I

{

x l

f I

1 I

f d

i i

e i

i i

l 1

o o

b C

i A

i w

1 W

(

em N

i o

w C

6Y I

i

.t I

O.xide Thickness Sensitivity - Temperature m

esas e

l l

f' v

l

?

k i

I i

f I

r i

I ti i

i i

I 1

9 t

t

I CONCLUSIONS FROM SENSITIVITY STUDIES I

i i

I l'

i i

i I

f

~

1 l

M 10 u

k

l i

f Thimble & RCC Bow without Interference t

i a,3p i

I i

5 f

L h

h I

t t

i i

i e

{

6 e

11

1 Thimble & RCC Bow with Interference i

l l

- a5 i

l D

h k.

l

(

l t

l 12

a w

n s

6im a&A m

4,m,

,eiAam,6M-

-n.:

a4 4 e

,-a.,,,,,,,

s 44 r--Ar.A4 4m,-_muam4_Aegms-umn&_.a,-.

_4maa,_,4_am.k

,am,,_p~

u aJ4&

g

_A Ar._.6, a.

u

.A i

I l

=3 m

~

i 1

1 I

4 i

1 1

1 i

a i

k.

b

]

d N

.o J

W l

N 4

y 4

m NQ 4

4 1

N b

1

.i 4

a I

4 1

I 4

A h

1 1

e Guide Thimble Dashpot (Span 1)

Measured vs. Predicted Drag i

i f

l 1

1 t

I t

t i

)

t 6

I t

14 i

t i

Upper Guide Thimble Measured vs. Predicted Drag I

L L

[

l t

r e

{

e t

i i

i i

g M

15 i

i

South Texas Guide Thimble Dashpot Measured vs. Predicted Drag l

1 I

f i

i h

[

i t

I t

i

{

l

!i 16

South Texas Guide Thimble Dashpot Measured vs. Predicted Drag Eung 17

t South Texas Vpper Guide Thimble Measured vs. Predicted Drag h

i i

aume I8

.,s.a

.s.r ns a

.u

-ax.

--a.-

mn-..wm

-an,a.---.ua,--.-----a.-a..--.--

.s - ~~rma.

---~--m

-n,.-a-n----.-e

..e-.-.--.

I e

I I-I N ']

i 1

e3 6

es Z

t I

W i

9 l

i

.~

I C

m C

to Nx o>

bU

-C I

I

1 4

s I

l l

4 i

i i

ce 6

-N wCW O

to 1

Nuo

@kU

-C I

l

)

.l 1

1 i

Repeatability of Drag Data abc i

t k

t I

l i

f i

t i

6

)

I t

I L

h i

f f

i 21 t

I

k Drag Work vs. Insertion Distance

-ahp I

?

i i

i i

i i

i I

I l

l i

i i

l s

i 5

22

t Measured Drag Work for RCCAs Plant Names

- ST I

i t

i I

[

i i

i i

t I

i 1

t 23 t

-a

9 Measured Drag Work for RCCAs e

Fuel Types i

r i

f i

f i

l s

t i

t l

l 1

l l

l l

l

\\

t l

i i

h i

k f

24

Measured Drag-Work Vs Fluence Selected Assemblies i

=

i i

l l

I i

l

[

l

~

=

25

Predicted Drag-Work vs. Fluence I

Selected Assembhes t

i i

~

l i

i i

i l

l 26 t

Measured vs. Predicted Drag-Work Selected Assemblies i

I l

l i

f l

i i

s e

r' t

27 i

Comparison of Measured and Predicted Drag-Work i

I I

r i

t t

[

t l

28

k r

South Texas Measured. Drag-Work for RCCAs I

E

(

1 I

i l

l t

L

?

I L

3 k

t i

man W

29 i

i

.-_.,I.

r 4

South Texas Measured Drag-Work vs. Fluence s.

l i

t P

r 3

h I

I i

i f

i i

E t

k i

i s

I l

I i

30 t

i

k I

South Texas Predicted Drag-Work vs. Fluence ahp n

h r

o 9

I a

I i

I I

5 I

k 6

t I

t 6

m l

h i

31

South Texas Measured vs. Predicted Drag-Work i

-ahp h

I I

i I

I t

[

i i

=

l 32

ZIRLO $TRUCTURES l

t i

i i

F/A Mechanical Design--key properties l

i MECHANICAL PROPERTIES i

t

-Strength i

-Creep l

1 CORROSION i

GROWTH i

33 i

I

ZIRLO STRUCTURES Thimble Yield Stress t

i i

6 t

)

i i

f l

t I

t

{

t m

34

ZIRLO STRUCTURES 1

Ciadding Creep i

W Wi I

r i

I I

i i

t' l

i s

f.

t L

P e

i

[

J 1

I i

l 35 i

i L

- - - - - - - - - ^ ^ - - - ^ - - ^ - ^ - ^ ~ - - ~ ^ ^ - ~ ~ - - - ^ - ~ ^ ~ ~ ~ '

~

~ ~ ~ ~~

~~

4 1

ZIRLO STRUCTURES RXA Thermal Creep I

t E

h I

L 4

r 1

?

l l

5 i

M i

36

ZIRLO STRUCTURES Cladding Corrosion 1

m i

?

h L

L i

i

(

~

f 37 i

f

)

U

'44-M49 4 4h.km&4 %

4.su-s.d.&

A 4hehhah.E h a,_m:

_.__AE_.,q.Ma5 6E A.h a hhD..a.4,.4.4&.-M_4a5_am,4 M

4 G2....h h

a.=4,,

J4 e

4mmA k

j f

ZIRLO STRUCTURES f

Autoclave Corrosion i

M 1

- a,$

i i

e I

i l

i

[

t i

l J

t L

)

38

.... ~ _...

__..____._,m.._....-__._._..____...___.-....._...._....-m.

.....m..m

._,..__m..__-_____.._.__u.m_.

1.

e l

1 i

l M

J l

4 1

G0, p4

.h U

m

w P*WN b

O,. N h

mb i

i

ZIRLO STRUCTURES i

~

1 ZIRLO Rod Growth r

4 t

i l

i i

+

I

?

I i

t 1

5 e

k I

i 1

emud G

40

.ZIRLO STRUCTURES i

~

s Growth from Corrosion t

- op i

t i

i

(

[

i i

i I

i 41 i

i

ZIRLO STRUCTURES ZIRLO Assembly Growth

- at 42

h ZIRLO STRUCTURES

~

Summary: ZIRLO Growth 1

~

89 i

i l

r t

k i

I f

I i

r f

I L

i i

e f

==a t

t L

i l

43 r

i

ZIRLO STRUCTURES i

POST IRRADIATION PLANS l

k h

abp I

i r

i I

v t

i i

i i

f' l

W t

t 44

"A.49 daw +4W L.4 b-bth-4.4%-4M hw4---E ad aL = 4mm 4

A-44_u4MLwAh-=ut a-=a4e

--4.

B.

4mW4.-

4-4---.*-4om-b aQe-Wam.

.M

%W M

a--

-esM 2 am - EE-Lhas%L

_>Em 4 J-.s-m.w,h-as 4hJa h

h h

ZIRLO STRUCTURES

~

t Summary i

k i

t l

i i

t i

f l

I L

h i

I f

t f

i 5

I L

e nm.

=

t t

I I

45 r

l

NRC 96-01 Drag Data

~

(Total and Upper Guide Thimble Drag Data)

- ax 46

NRC 96-01 Drag Data (Upper Guide Thimble Drag vs. Fluence) t a

4

[

1 47

~

NRC 96-01 Drag Data 1

(Total Drag vs. Fluence) aum t

t

[

[

[

l t

t t

t P

t t

[

i m

48 i

{

i i

Special W Fuel Assembly Features l

l ZIRLO i

- Basic material property differences between ZIRLO and l

Zirc-4 are significant relative to RCCAs t

Growth rate vs burnup 1

Fuel rod growth vs burnup i

Oxide data

- Comparison of Wolf Creek 50H FA with and w/o ZIRLO j

,b,c j

a r

49 j

l

Special W Fuel Assembly Features

~

(continued) i

- ZIRLO skeletons are significantly less susceptible than Zirc-4 skeletons due to material properties such as creep, corrosion, etc.

i i

- Additional high burnup data will be available from demos i

- ZIRLO skeletons require no burnup restrictions given current burnup license limit 50 i

l i

Special W Fuel Assembly Features

]

t IF Ms l!

- IF M FAs are less susceptible than non-IFM FAs i

i Reduced drag in upper guide tube region c ue to increased stiffness i

i Reduced compressive loads due to increased AP from IFM grids I

l l

51 l

Special W Fuel Assembly Features IF;M Conclusions No reported incomplete insertion for IF Ms i

Drag tests with IF M do not exceed F-Spec j

i Mechanical model predicts lower thimble tube bow for IF M FA than 'Volf Creek H50 l

No Restric'1ons on IF Ms up to Current Burnup Limit f

l l

52

o I

Recommendation for Current Operating W Cores

• No restriction for IFM or ZIRLO skeleton FAs

• No restriction for low temperature plant or 2 cycle I

FAs j

i Temperature > 615aF and 3 cycle FA (18 months)

- 12 Foot - 40,000 : MWD /MWT l

- 14 Foot - 30,000 : MWD /MWT j

• Temperature < 615aF j

- 12 Foot - no restrictions

• Process to assess acceptability should the above values be exceeded

/i 53

Process to Address Acceptability for Operating Plant above W Recommended Values SAFETY EVALUATION PREDICTIVE EVALUATION Potential for Incomplete Determine Acceptable Using Mechanical l

Model and Plant Data l

Accident Analysis (as needed)

Yes No i

t i

No Additional Perform Measurerrent Action Determine if/When e

Additional Test 54

Model Predictive Methodology Obtain necessary input of fuel assembly history

~

a,b,e T

If predicted burnup < EOC fluence by more than 2500 MWD /MTU i

(Additional test required)

)

[

55

t Fuel Assembly Near/ Longer Term Actions to Enhance Margin to Incomplete Rod Insertion F

i i

i l

I 6

l i

i t

P I

i

?

b and 56

Fuel Assembly Near/ Longer Term Actions to Enhance i

Margin to Incomplete Rod Insertion i

man ap

\\

l I

i i

i h

i l

t i

~

i s

enn I

i 1

57

l

\\

Conclusions I

i No restrictions required for IFM and /or ZIRLO based i

on current burnup licensing limit A mechanical model has been revised to predict span drag i

A methodology was developed to predict incomplete insertion 6

i i

58

~.

e WESTINGHOUSE OWNERS GROUPS WOG / NRC INFORMATION MEETING APRIL 16,1997 i

II. WOG PRESENTATIONS FuelIssues

- Formation of WOG Fuel Working Group

• FormationMeetingheldMarch7,-1997

• Next Meeting scheduled for May 8,1997

- WOGFuelWorkingGroupCharter Central focus for fuelissues

• Provide coordination with NEI, EPRI, and other fuel vendors Establish framework for WOG/ Industry response to issues

. Identify strategic fuel issues and action plan 1

meanmas 1

WESTINGHOUSE OWNERS GROUPS WOG / NRC INFORMATION MEETING APRIL 16,1997 II. WOG PRESENTATIONS --

Fuel Issues --

+

- WOGFuelWorkingGroupPotential ActivitiesBulletin 96-01, Incomplete RCCA Insertion

• Development ofindustry :tandard for fuel designs INPO SOER 96-02 (approach w issues / peer review)

. Standard for handling fuel design cieges

. Review of Reload Safety Analysis Checklbt process

• Standardforfueluprating High burn-up fuel designs

- 00: Pursumg Formation of a Fuel Issues Group within NEI

\\

l I

u

i a

=

l e

WESTINGHOUSE OWNERS GROUPS WOG / NRC INFORMATION MEETING APRIL 16,1997 II. WOG PRESENTATIONS --

Fuel Issues --

J

+

- Bulletin 96-01,Incorrplete RCCA Insertion (IRI)

• WOG Continues to Participate In & MonitorIRI Activities

- Issue returned from Analysis Subcommittee to IRG

- Prelimmary plans underway to provide response / comments on proposed Supplementto Bulletin 96 01

- May request comment period extension iflimited to 30 days m

)

order to compile comments from all WOG members i

WESTINGHOUSE OWNERS GROUPS WOG / NRCINFORMATION MEETING APRIL 16,1997 II. WOG PitESENTATIONS --

Fuel Issues --

+

- Bulletin 96-01, Incomplete RCCA Insertion (IRI)- continued Attending All Westinghouse /NRC meetings

- January 10 initial discussions ofissue management

- February 19 detail discussion of W mechanical model

- April 17 further discussion ofE, mechanical model

• Currently evaluating alternatives as a means to reduce the need to pert nn mid<ycle tests muusm.,

i

l e

l WESTINGHOUSE OWNERS GROUPS WOG / NRC INFORMATION MEETING APRIL 16,1997 j

II. WOG PRESENTATIONS --

Fuel Issues --

+

J

- Bulletin 96-01, Incomplete RCCA Insertion (IRl)- continued

• Short Term: Manage Existing Cores with W Fuel l

- Use E model to determme susceptibility

+ BumuplessthanNRClimit-Noactionrequired 4

• Burnup greater than NRC limit and less than E inodel susceptibilitylimit EOCtesting

• Bumup greater than the E model susceptibility limits -

Avoid if possible (new cores); perform safety evaluation; testmg as appropriate i

i l

WESTINGHOUSE OWNERS GROUPS WOG / NRC INFORMATION MEETING APRIL 16,1997 II. WOG PRESENTATIONS --

FuelIssues

+

- Bulletin 96-01, Incomplete RCCA Insertion (IRI).-

+ Intermediate Term: Program to Further Confirm Model

- Data from existing high burnup assemblies

- Data from future high burnup assemblies

. Long Term Ehmmation ofProblem

- Use model to assess the effectiveness of new aaign features

- Fuel Working Group to plan utilization of operating experience of fuel assemblies with new design features

-u= >

e

e CC*

Mr. Nicholas J. Liparulo Westinghouse Electric Corporation Mail Stop ECE 4-15 P.O. Box 355 Pittsburgh, PA 15230-0355 Mr. Henry A. Sepp Westinghouse Electric Corporation Mail Stop ECE 4-07A P.O. Box 355 Pittsburgh, PA 15230-0355 Mr. Andrew Drake, Project Manager Westinghouse Owners Group Mail Stop ECE 5-16 P.O. Box 355 Pittsburgh, PA 15230-0355 1

i