Presentation of EMF-93- 177(P)> Reported pressure limit, Table 6.1, p. 6-10: > Presentation of EMF-93-177(P) Revision I to NRC -2006-03 Rockville, MO 15 > Presentation of EMF-93-177(P)

Presentation of EMF-93- 177(P)Revision I

to NRC

Mark SmithJerry Holm

Framatome ANP, Inc.

NRC Rockville Offices, March 2005

Cn=EszK > Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - RockMille, MD 2

A Brief Review ofEMF-93- 1 77(P)

Revision ITopical Report

Mechanical Designfor B WR Fuel Channels

Issued January 2005

m 2 ;x^ ll J, A tOhl I I > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 3

Fuel Channel Topical Report Review

> Agenda

* Background

* Presentation of corrected method

* Method illustrated for the 80-mil fuel channel design

* Comparison between incorrect and correct method

* Brief description of incorrect method

* What changed from Revision 0 of the report

- Error correction

- Methods applicability

- Updates to channel bow measurements

ca"UrNO S > Pmsentatlon of EMF-93.177(P) Revision Ito NRC - 2005-03 - RocAville, MD 4> Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 4

Fuel Channel Topical Report ReviewBackground

> Background on EMF-93-177(P)(A)+ Describes the design criteria and analysis methods for

evaluating fuel channels (mechanical analyses)* Stress, strain and loading limits* Cyclic fatigue* Corrosion and hydrogen pickup

* Deflection (bulge and bow)

+ Normal operation, AOO and accident conditions

+ Results are presented for four fuel channel designs* 80mil FC* BWR/6 100-mil FC

* BWR/3,4 AFC (Advanced Fuel Channel)* BWRI6 AFC

> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 5


> Background on EMF-93-177(P)(A)Stress, strain and loading limits* One aspect of the fuel channel strength is the ability to

withstand the differential pressure across the channel wall

* The standard approach would be to use the ASME B&PVCode stress limits and perform a linear, elastic stressanalysis, for example:- Primary membrane stress c 1.0 Sm

- Primary membrane + bending stress ...

* The majority of modern fuel channel designs (not justFANP designs) cannot satisfy the conservative ASMEelastic analysis stress criteria making it necessary to resortto options in the code. Options include:- Limit analysis

- Plastic analysis

*6 > Presentation of EMF-93-1 77(P) Revision Ito NRC - 2005-03 - Rockville, MD 6CJap1A96 > Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 6

> E


3ackground+ Last Fall, a FANP engineer was reading a publication on

common pitfalls in performing finite element analyses tothe ASME B&PV Code and realized we had fallen intoone of the common traps.* We performed a plastic analysis and labeled it as a "Limit

Analysis" in the channel report.* Because of this confusion, we mixed the ASME Code

criteria from a Limit Analysis with the Plastic Analysismethod.

.0 > Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - RocAvilIe, MD 7> Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 7

Fuel Channel Topical Report ReviewBasic Requirements

Requirements to satisfy are in SRP 4.2(paraphrased below):

* Stress, strain and loading limits for fuel channels shallbe provided ... Section III of ASME Code are acceptable.

* Dimensional changes of the fuel channel ... must beincluded in the design analysis to establish operationaltolerances.

Thus, there are two analyses for channel strength

* Analyze stresses or loads to avoid ultimate failure

+ Analyze deformation to prevent interference with controlblade

U UJ _Nt]6 .6 > Presentation of EMF.93-177(P) Revision Ito NRC - 2005-03 - Rockville, MD 8> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 8

Fuel Channel Topical Report ReviewCorrect Method - Example

> The method of calculating the allowabledifferential pressure is illustrated for the 80-milfuel channel design. The same methods alsoapply to other fuel channels (e.g., "Advanced FuelChannel" or AFC with thick corners I thin sidewalls)

+ Next slides will illustrate the calculation of the allowablepressure as based on the allowable deformation.

-. S > Presentation of EMF-93.177(P) Revision I to NRC- 2005-03 - Rockville, MD 9

Fuel Channel Topical Report ReviewAllowable Pressure

m i;-;1:, ' o ,: I,', ~I" S > Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - Rockville, MD 10

L> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 10

Fuel Channel Topical Report ReviewPressure Limit - Based on Deformation

> Allowable pressure based on deformation+ A finite element model is set up for the fuel channel

geometry and material - the ANSYS code is used

* The model includes the following options:

* *

* A pressure load is applied in increments until the[ ] becomes unacceptable

[ ] cannot exceed [ I

a � VV JI F-N to] J, I 11 .0 > Presentation of EMF-93-177(P) Revision ito NRC - 2005-03 - Rociwille. MD 11

> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 1 1


> Fuel Channel is modeled as a

I I> A distributed load is applied

to simulate the hydraulic load

M�;Uej-ltqull > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 12


> Material stress-straincurve for ANSYSinput (see Figure 6.2,p. 6-16)

i > Presentation of EMF-93-177(P) Revision 1to NRC- 2005-03- Rockville, MD 113353a 13IL


> The deformation is calculated as a function ofpressure - limit is [ ]

L& > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MDNJO;AM ,, ^1^ ,' U 14Ma


> Reported pressure limit, Table 6.1, p. 6-10:

> Presentation of EMF-93-177(P) Revision I to NRC - 2006-03 - Rockville, MO 15> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 15

Fuel Channel Topical Report ReviewPlastic Analysis Collapse Load

The allowable pressure from the plastic analysis

collapse load method is calculated by the

following steps (ASME B&PV Code, Section 111,

Division 1, NB-3213.24, NB-3213.25, NB-3228.3

and Appendix F):

* Determine the collapse load from a plastic analysis

+ The pressure (load) limit is:

1 Load limit

Normal operation + < 2/3 collapse loadAOOAccident conditions < collapse load

Nallw -Io _- lnIg[A > Presentation of EMF-93.177(P) Revision I to NRC - 2005-03 - RockviIIe, MD 16

> Presentation of EMF-93-1 77(P) Revision 1 to NRC - 2005-03 - Rockville, MD 16


> The collapsev ~Coll" limit line

load is Rtron line Cottapse lord point

determined bythe double-elastic slopemethod(Appendix II- Fi.1430 of Code):

Strain or Displamment

FIG. 11-1430-1 CONSTRUCTION FOR 111430

a a OMM to] M =VX1 IA 11, LOAN > Presentation of EMF.93.177(P) Revision Ito NRC - 2005-03 - Rockville, MD 17

IL> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 17


Using the same plastic analysis previouslydescribed, the resulting plot of the center-wallnode:

LJJ;awklxl~l S > Presentation of EMF-93-177(P) Revision ito NRC - 2005-03 - Rockville, MD 18> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 18


> Because the collapse load was not reached up to

I ], the collapse load is taken to be [ ]> ANSYS analysis uses von Mises yield criterion.

The Code is based on maximum shear stresscriterion (but allows von Mises).* The shear stress criterion is more conservative than von

Mises and differs, at the most, by approximately 15%.

* Adjusted collapse load according to maximum shearstress criterion:

I ]

.0 > Presentation of EMF-93-1 77(P) Revision Ito NRC- 2005-03 - Rockille, MD 19> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 19


> Allowable pressure load based on plasticanalysis collapse load method:

4

> Note: results are non-limiting relative to the [] limit obtained by the deformation criterion

C 3 [1a. Ii > Presentation of EMF-93-177(P) Revision I to NRC- 2005-03 - Rockville, MD 20

Fuel Channel Topical Report ReviewPressure Limit Summary (Intermediate)

• Two analyses have been presented thus far:+ Allowable pressure based on deformation limit

+ Plastic analysis collapse load

• The analyses establish limits for both normaloperation + AOO, and accident conditions

• The allowable pressure of [ ] applies toboth normal operation + AOO and accidentconditions because the same stress-strain curveis used for both conditions+ But ... a deformation of [

]Need an additional criterion for [ ]

.0 > Presentation of EMF.93-177(P) Revision I to NRC- 2OO5�O3 - Rockville, MD 21> Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 21

Fuel Channel Topical Report ReviewPressure Limit for Normal Operation

> In order to avoid plastic deformation duringnormal operation:+ Limit pressure such that [

* This criterion allows for a small amount of yielding onthe[

* Channel dimensional tolerance inputs to the analysisare selected to maximize stresses, minimum specifiedyield strength is used.* Result - maximum permanent deformation is insignificant -

less than a few mils

C016alig S > Pmsentat!an of EMF.93.177(P) Revision I to NRC - 2005-03 - Rockillie, MD 22> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 22


> To check for yielding at the corners:+ Same ANSYS model as before, except an elastic

analysis

+ Increase the pressure load until the [

* Result: [ Highest stress

] limit for location l

normaloperation

C===M& > Pmsentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - Rockville, MO 23

L> Presentation of EMP-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 23


> Result reported in Table 6.1, p. 6-10:

E _-" o 1=F I LS > Presentation of EMF-93-1 77(P) Revision Ito NRC - 2005-03 - Rockville, MD 24

> Presentation of EMF-93-1 77(PJ Revision I to NRC - 2005-03 - Rockville, MD 24

Fuel Channel Topical Report ReviewComparison of Correct & Incorrect Method

> A brief review of the error and a comparison

between the Revision 0 and Revision 1 allowable

load calculations+ Terminology

* Revision 0 method

* Plastic Analysis Collapse Load method (Revision 1)

* The error that was made

* A comparison of the key features between the incorrect

and corrected methods

_ orrfe> Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - Rockville, MD 25> Presentation of EMF-93-177(P) Revision 1 to NRC - 2005-03 - Rockville, MD 25

>


The Revision 0 analysis was erroneously labeledas a "Limit Analysis Collapse Load" methodaccording to ASME terminology* The analysis used a large deflection option and the

analysis was carried into post-buckling behavior - this

is not allowed for a limit analysis

* Because the analysis was mis-labeled as a limitanalysis, the stress-strain curve and allowable loadcriteria from a limit analysis were mistakenly used

+ But, because of the way the analysis was done, thePlastic Analysis Collapse Load stress-strain curve andallowable load criteria should have been used.

.6 > Presentation of EMF.93-177(P) Revision Ito NRC- 2005-03 - RockviIle, MD 26> Presentation of EMF-93-177(P) Revision I to NRC - 2005W3 - Rockville, MD 26


> Result comparison for the 80-mil FC

40 *

(elMO 0 > Presentation of EMF..93-177(P) Revision Ito NRC-. 2005-03- Rockville, MD 27> Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 27


> Key differences+ "Revision 0 analysis" vs. Plastic Analysis Collapse Load

L I.-

1*

E ;-1I ftto II=1XAII e

'Presentation otEMF.93-177(P) Revision ito NRC- 2005-03 - Rockviie, MD 28> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockvlls, MD 28


> Comparison of stress-strain curve inputs+ For a limit analysis, the stress-strain curves are

prescribed in the Code (see Figure 6.2, p. 6-17 of theRevision 0 report)* For normal operation + AOO, the curve is perfectly elastic -

perfectly plastic with yielding occurring at 1.5 Sm or 0.5 Su* For accident conditions, the curve is perfectly elastic -

perfectly plastic with yielding occurring at 1.2 Sy

The Revision 1 curve includes strain hardening withyielding occurring at Sy* Less conservative than before for normal operation + AOO* For accident conditions, results are about the same as

before- Criteria of (0.9 x collapse load) versus (1 x collapse load) and

the use of 1.15 factor also lead to differences in results

-. .6 > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 29


> Plot comparison of the stress-strain curves

EJOIWAILOV, I k > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 30


> Collapse load determination+ The Revision 0 analysis used the point of instability

(deformations increase without bound)

*]+ The Revision 1 analysis also [

IRemember - the plastic analysis collapse load results

are not actually used - the results come from the allowed deformation

S > Presentation of EMF.93.177(P) Revision Ito NRC- 2005-03 - Rockillie, MD 31> Presentation of EMF-93 177(P) Revision I to NRC - 2005-03 - Rockville, MD 31


> The allowable load as based on deformationdiffers from before because:+ A different stress-strain curve is used

* The same stress-strain curve as used in the PlasticAnalysis Collapse Load calculation is used in calculatingthe deformations. This curve is used for both normaloperation + AOO and for accident conditions

> Presentation of EMF-93-1 77(P) Revision I to NRC - 2005-03 - Rockville, MD 32

Fuel Channel Topical Report ReviewChanges in the Report

> The following changes were made in the report:Words describing the criteria, method and results forthe pressure load analysis were revised to that of thePlastic Analysis Collapse Load.

Words were added in Section 1.4 indicating that themethods and criteria can be applied to channel designsother than those described in the report.

Section 7.2: Indicated that the channel measurementdata will be updated as new measurements areacquired.

> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 33


> Added an abstract (new required format)

> 1.1: Deleted words about Advanced Fuel Channelleads (AFC is now widely used)

> 1 4: Words describing limit analysis werechanged to plastic analysis collapse load

> 1.4: Added words stating that new analysesusing the criteria and methods in the report canbe performed if the operating conditions, etc. arechanged

> Tables 1.1, 1.2: Revised the results for theallowable pressure load

> Presentation of EMF-93.177(P) Revision Ito NRC - 2005-03 - RocAville, MD 34,M.rMEEMk > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 34


• Table 1.2: Made minor correction to incorporateRAI on Revision 0 report (rearranged words)

• Table 1.2: Gusset load rating changed slightlybecause of the updated tensile properties in theFANP material specifications

Compare hot yield and ultimate in Table 2.1

• Table 1.1: Updated results for 54 MWd/kgU

burnup (information previously communicated toNRC (Mallay to NRC, NRC:99:031, July 23,1999)

> Presentation of EMF-93.1 77(P) Revision Ito NRC- 2005-03 - Rock..'iIIe, MD 35S

L> Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockvilie, MD 35


* 2.2, Table 2.1: Updated material properties withcurrent, specified minimum yield and ultimatestrength

* 3.2.1: Revised design criteria description toplastic analysis collapse load

* 3.3.2, Table 3.2: Again, updated gusset loadbased on revised tensile properties

* Tables 3.1, 3.2: Again, updated stress intensitylimits and design criteria

S > Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - Rockville, MD 36

L > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 36


> 4.1.1: Revised description for plastic analysiscollapse load method

> 6.1.1: Evaluation section changed to plastic

analysis collapse load+ Added normal operation analysis to preclude

deformation

+ Now use ANSYS instead of ABAQUS

+ Described stress-strain curve used for analysis

> Table 6.1: Included revised allowable pressure

load results and result for normal operation

Mii-M 161, .ki l'OS > Presentation of EMF.93.177(P) Revision Ito NRC - 2005-03 - Rockville, MD 37

> Presentation of EMF-93 177(P) Revision I to NRC - 2005-03 - Rockville, MD 37


> 6.2.1: Described revised result for axialmembrane stress (last two paragraphs) due totensile property update

> Table 6.4: Included revised allowable pressureload results

> Figures 6.1, 6.2, 6.3: New figures for revisedcalculations• Figure 6.1: Mesh is a little finer

+ Figure 6.2: Stress-strain curve revised from before (butthe same as Figure A.2 in Rev. 0 report)

+ Figure 6.3: New results for pressure versus deflectionplot

> Presentation of EMF-93-177(P) Revision Ito NRC - 2005-03 - Rockville, MD 38

_Ma I L > Presentation of EMF-93-177(P) Revision I to NRC - 2005-03 - Rockville, MD 38


> 7.2: Channel bowlbulge data are described here

+ New data were acquired last year at Susquehanna Unit 1and Quad Cities Unit 2

* New data will be acquired this year at three more plants

+ The revised wording allows FANP to incorporate the

new data into our database without a new submittal to

the NRC

> Table 7.1: Added channel deformation results for

54 MWd/kgU (as previously mentioned)

> 8.0: Added reference 18 for ANSYS

> Presentation of EMF-93.177(P) Revision I to NRC - 2005-03 - Rockville, MD 39

Documents

Presentation of EMF-93- 177(P)> Reported pressure limit, Table 6.1, p. 6-10: > Presentation of EMF-93-177(P) Revision I to NRC -2006-03 Rockville, MO 15 > Presentation of EMF-93-177(P)