View source for Information Notice 2012-09, PWROG-16043-NP-A, Revision 2, PWROG Program to Address NRC Information Notice 2012-09: Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength for Westinghouse and CE PWR Fuel Designs.

{{Adams
| number = ML20007E353
| issue date = 11/30/2019
| title = PWROG-16043-NP-A, Revision 2, PWROG Program to Address NRC Information Notice 2012-09: Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength for Westinghouse and CE PWR Fuel Designs.
| author name = Jiang J, Lu R
| author affiliation = PWR Owners Group, Westinghouse Electric Co, LLC
| addressee name = 
| addressee affiliation = NRC/NRR
| docket = 99902037
| license number = 
| contact person = 
| case reference number = OG-19-251, PA-ASC-1169
| document report number = PWROG-16043-NP-A, Rev 2
| document type = Topical Report
| page count = 152
}}
{{#Wiki_filter:PWROG-16043-NP-A

Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 PWROG PROGRAM TO ADDRESS NRC INFORMATION

NOTICE 2012-09: "IRRADIATION EFFECTS ON FUEL

ASSEMBLY SPACER GRID CRUSH STRENGTH" FOR

WESTINGHOUSE AND CE PWR FUEL DESIGNS

Analysis Committee

PA-ASC-1169, Revision 4 November 2019
*. @ Westinghouse        *
          -       .  -    - -           -      .               -- -- . - -- -
                                                        . . --

WESTINGHOUSE NON-PROPRIETARY CLASS 3                   ii

PWROG-16043-NP-A

Revision 2

===PWROG PROGRAM TO ADDRESS NRC INFORMATION===
NOTICE 2012-09: "IRRADIATION EFFECTS ON FUEL

ASSEMBLY SPACER GRID CRUSH STRENGTH". FOR

WESTINGHOUSE AND CE PWR FUEL .DESIGNS

PA-ASC-1169, Revision 4 RogerY. Lu*
                           PWR Fuel Technology

Jane Xiaoyan Jiang*
                            Product Engineering

November 2019 Westinghouse Electric Company LLC

1000 Westinghouse Drive

Cranberry Township, PA 16066, USA

C 2019 Westinghouse Electnc Company LLC

All Rights Reserved

PWROG-16043-NP-A                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                     iii

Reviewer: James D. Andrachek*
                                      Licensing Engineering

Approved: Olin M. McRae*, Manager

PWR Fuel Technology

Approved: Kevin T. Lasswell*, Manager

Product Engineering

Approved: Chad Holderbaum*, Project Manager

PWR Owners Group PMO

*Electronically approved records are authenticated in the electronic document management system.

PWROG-16043-NP-A                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                      iv

ACKNOWLEDGEMENTS

This report was developed and funded by the PWR Owners Group under the leadership of the

participating utility representatives of the Analysis Committee. The author would like to thank all

the people and/or organizations for their valuable contributions to this report:
PWR Owners Group - Dr. Robert Florian, Loic Was, Thomas Remick, Doug Pollock, Pete

Kennamore, Paula Larouere, Brian Mount and Kurt Flaig.

Westinghouse Product Engineering and Methods Technology and Licensing - Naomi Marshall, Jill Sinegar, Jiwei Wang, Carrie Wood, Paul Evans, Jin Liu, Lisa Dudas, Dr. Jeff Norrell and

Nathan Payne.

LEGAL NOTICE

This report was prepared as an account of work performed by Westinghouse Electric

Company LLC. Neither Westinghouse Electric Company LLC, nor any person acting on its

behalf:
1.        Makes any warranty or representation, express or implied including the warranties of

fitness for a particular purpose or merchantability, with respect to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of

any information, apparatus, method, or process disclosed in this report may not infringe

privately owned rights; or

2.        Assumes any liabilities with respect to the use of, or for damages resulting from the use

of, any information, apparatus, method, or process dis<;:lqsed i11_ this_!~P-Qrt.

-     --- --- --   --    ----   --- ----   -  --      --
                                          COPYRIGHT NOTICE

This report has been prepared by Westinghouse Electric Company LLC and bears a

Westinghouse-Electric Company copyright notice. Information in this report is the property of

and contains copyright material owned by Westinghouse Electric Company LLC and /or its

subcontractors and suppliers. It is transmitted to you in confidence and trust, and you agree to

treat this document and the material contained therein in strict accordance with the terms and

conditions of the agreement under which it was provided to you.

As a participating member of this task, you are permitted to make the number of copies of the

information contained in this report that are necessary for your internal use in connection with

your implementation of the report results for your plant(s) in your normal conduct of business.

Should implementation of this report involve a third party, you are permitted to make the number

of copies of the information contained in this report that are necessary for the third party's use in

supporting your implementation at your plant(s) in your normal conduct of business if you have

PWROG-16043-NP-A                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                      V

received the prior, written consent of Westinghouse Electric Company LLC to transmit this

infonnation to a third party or parties. All copies made by you must include the copyright notice

in all instances and the proprietary notice if the original was identified as proprietary.

DISTRIBUTION NOTICE

This report was prepared for the PWR Owners Group. This Distribution Notice is intended to

establish guidance for access to this information. This report (including proprietary and

non-proprietary versions) is not to be provided to any individual or organization outside of the

PWR Owners Group program participants without prior written approval of the PWR Owners

Group Program Management Office. However, prior written approval is not required for program

participants to provide copies of Class 3 Non-Proprietary reports to third parties that are

supporting implementation at their plant, and for submittals to the NRC

PWROG-16043-N P-A                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                  vi

NRC FINAL SAFETY EVALUATION

This section contains the following documents:
    1. NRG cover letter, "Final Safety Evaluation for Pressurized Water Reactor Owner's Group

Topical Report PWROG-16043-P, Revision 2, "PWROG Program to Address U.S.

Nuclear Regulatory Commission Information Notice 2012-09: 'Irradiation Effects on Fuel

Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel DesignsD

(EPID: L-2018-TOP-0021), dated October 31, 2019.

2. "Final Safety Evaluation by the of Nuclear Reactor Regulation for Topical Report

PWROG-16043-P, Revision 2, "PWROG Program to Address U.S. Nuclear Regulatory

Commission Information Notice 2012-09: 'Irradiation Effects on Fuel Assembly Spacer

Grid Crush Strength' for Westinghouse and CE PWR Fuel DesignsD Pressurized Water

Reactor Owners Group (PWROG), dated May 17, 2019.

PWROG-16043-NP-A                                                                  November 2019 Revision 2

VVESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       vii

8FR61AL l:IBE 8NLY       PR8PRIETAR&#xa5; INF8RMATION

UNITED STA'rES

NUCLEAR REGULATORY COMMISSION

WASHINGTON, o.c. ~ 1 October,31, 2019 Mr. W Anthony Nowinowskl

Executive Director

P'NR C>.vners Group, Program Management Office

Westinghouse Electric Company _
          1000 Westinghouse Drive, Suite 380
         _cranberry Township, PA 16066 SUBJECT:      FINAL SAFETY EVALUATION FOR PRESSURIZED WATER REACTOR

OWNERS GROUP TOPICAL REPORT PWROG-16043-P, REVISION 2,
                        "PWROG     PROGRAM TO ADDRESS U S. NUCLEAR REGULATORY

COMMISSION INFORMATION NOTICE 2012-09: 1RRADIATION EFFECTS ON

FUEL ASSEMBLY SPACER GRID CRUSH STRENGTH' FOR WESTINGHOUSE

AND CE PWR FUEL DESIGNS" (EPlb: L-201S.TOP--0021,)
          Dear Mr. Nowinowskl:
         By ~tter dated Febru;lry 1,. 2017 (Agency;wlde Documents Access and Management System

(ADAMS) Accession No. ML 1I039B050 ), the Pressurtzed Warer Reactor (PWR) Owners Group

(PWROG or the appl!cant).submltted to the U.S. Nuclear Regulatory Commission (NRC) staff

for r:!3Vfew hcensl~ topical report (TR) PWROG-16043-P, Revlslon *2, "PWROG Program to

Address NRC Information Notice 2012-09: 'Irradiation Effects on Fuel Assembly ~pacer Grid

Cn,ish Strength' for Westinghouse and CE [Combustion Engineering] PWR [pressurized water

reactor] Fusi Designs" ((ADAMS Package Accession ~o. ML 170396061), henceforth referred to

as the TR). Subsequent letters dated March 27, 2018, May 15, 2018, and May 15, 2018 (ADAMS Accession Nos. ML 18100A093, ML 181436462, and ML 18144A760, respectively),
         provide9 additional information that supplemented the Information provided In the February 1,
         2017, submittal.

The NRC staff review determined that the information provided In the TR and .respooses to NRC

staff requests for aQdltlonal Information adequately ~stratas that the proposed

methodologies to address end-of-life (EOL) effects on spa.per grids and to recover margin

through credit-for flowing water damping are acceptable for   use, subject to the limitations and

cond1tlqns contained In the enclosed draft safety evaluation (SE), with existing methodologies

that the NRC has previously found to be acceptable for analysis Qf fuel assembly structural

bebavt0r dl,Jring S(lismic and loss-of-coolant-accident events.

NOTICE: The enclosllre transmitted herewith contains Proprietary tnfurmatton.

When ~eoarated ~ the enclos~re. th!a transmittal ~ment la ~ontrolled.

*omOIA:l:: \:16E ONLY      PROPRIETARY l~FORM-Al'ION

PWROG-16043-NP-A                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                         viii

OFRCI.IY. Uli Q~Y PROPRHttM&#xa5; INFQRILO.TIQN

w.. Nowmwskl                                      -2- By letter dated August 22, 2018 (ADAMS Accession No. ML18186A625), the NRC' staff

provided the draft SE to the PNROG for r8Yi8w end comment. Per emai ~ on

JanlJ!:lfY 16, ~19 (ADAMS Accessk?n* No. ML19~18), the PWROG provided comments to

the ~ $ff. ~ email correspondence ori April 5, 201 ~. the ~c staff prov(~ a ~
         di:aft SE to the PNROO for review and comment. *Per. emaH and Its enclosure dated May 14,
         2019, and May 16, 2019, the PWROO provided          comments      to the NRC staff. The NRC

staff disposition tables for the draft SE comments can be fountf, In ADAMS Acce88lon

Noa. ML19071A239'1;md ML,192~~. ~pectiv91y. .                                    .

In accordance with the guidance providecron the NRC website, we request that tl18 PWRPG .

publlgh an approved V8(JK)li*of PWROGa-16043-P, Revision. 2 within three months of receipt of

this letter. The approved versions shall [nco,porata this letter 'and tll& enclosed' li0$* SE after.

1he tiUe page. For -NP versions, the PNROG shall strike the proprietary Information mar1dngs fr\
         this lajier and make ttie approprjate iadaotlons -~ adjustments to dOCl)JTl8flt ~
         classifications to the aftached SE. *Also, It must c;:ontaln historical~ Information; including

NRC requestsJor addltlqnal inform!,ltlon (RAfs) and*yow: f"81Hl9n&eS. The 8PJ)r9Vecl version ~ I

Include al'I "-A" (deslgnatlng approv6d) followfng the TR Identification symbol'. As. an alternative

to [!lcludlng,the R,AJs and'RAI ~ beh_lndthe tltle page, If c;:hanges.to the TR were

provided to lhe NRC st!lff to support the resolution of RAJ ~ and If the NRC S4lff

revjewed and approved'~ changes as descrlbe<;I in~ RAI ~ ~ lrB'~.ways

that the accepted: verslon'can.capture the RAls:
              1: The R.Als and RAJ* responses can be lnclul;led* ~ an appendix to the accepted version:
              2. The RAls and RAJ        respooses can be capbJsd In the form,of a_ table (lliserted after the

final SE) which summarizes t h e - ~ es shown In.the appi:oved \ierslon of~ lR

The table should reference the spacdlc RAJs and RAJ.responses wtilco resulted In any

changes, BS shqwn* (n the (!CCeptecf'version of tfl8 "f'R,                               ..

..

to

If futu~ (:hanges the NRC's*regu~tory ~ t s ~ - the acceptability of this TR,
         The PWROG'wlll be expected to revise the: TR appropriately orJustlfy tlielr i::ontlnued

~ for subsequent referencing. l.ice!l8868 ~renclng this TR would be expected*to

Justify their contli:ive,d api:>l]cabllfty-oF ~ their Plant using the revised~
         lfyo1.rhaye.any.questlons,.please con~ ~ason Drake at 301-415-8378.

~etNo.-~37 Encloouie:
          ~el SE'-*(~atar:"/)
PWROG-16043-NP-A                                                                                               November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     ix

U.S. Nuclear Regulat9ry Commission

Comment Resolution Table for PWROG-16043 Comment Text Location        PWROG Comment              NRC Response

Number  Page        Llne     (paraphrased)
           1       3           22-3f    It Is not cleat what the   The staff agrees that not all

purpose Is to refereru:.e  plants are lk:ensed under

Appendbc S of 10 CFR       Appendix S of .1 O CFR Part Q().

Part 50. Depending on      Howeverr some plants may be

the vintage of llcenslng   lcensed under this regulation, for plants, Appendix s of  or under Appendix A of j o CFR

10-CFR Part 50 as waif     Part 100, and use the approach

as Appe!J(llx A of         described In PWROG-16043 as

10 CFR Part 100 may        part of thefr demonstration that

not t;>e the llpenslng     the criteria are met. Thus, the

bagjs_                     NRC staff considered whether

~ PWORG-16043         approach

would be Inconsistent with these

criteria.

The text has been revised to

blcl~ Appendix A of 10 CFR

Part 100 (which contains similar

requirements) and. to clarify that

the specific regulatory

reQuirements are sllEH!peclflc.

'2       16          45       Typo -    "fott" should be The staff agrees, and the

'b"*.                      proposed change was

lncoroorated as-is ..

3       17          22-28    The   proposed changes     The staff agrees. This was an

_on Page 16, Lines 13-      oversight, and* the prlof

19 of the PWROG            recommendations were

comments on the            incorporated ~--
                                        original DSE were not

Incorporated. The NRC

response to PWROG

Cor'nmerrt 1 was not

irl<:qrporated (refer tQ

.NRC response matrix on

PWROG comments.)
                                                                                           Attachment

PWROG-16043-NP-A                                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                   X

omGIM. Y8&#xa3; ONLY PR0PRll?TARY INFO!WA:noN

w. Nowinowskl

SUBJECT: FINAL SAFETY EVALUATION FOR PRESSURJZEDWATER REACTOR

QV,/NERS GROUP TOPICAL REPORT PVVROG-1604J;.P, REVISION 2,
                     "PWROG PROGRAM TO ABDRESS NRC INFORMATJ0N NOTICE 2012.:09:
                     1RRADIATION EFFECTS ON FUEL ASSEMBLY SPAGER GRID CRUSH

STRENG_Ttf FOR WESTINGHOUSE ANP CE PWR FUEL DESIGN$" (EPIO: L-
                     2016-l"OP-0021) DATED OCTOBER 31, 2019 DISTRIBUtlQN:
         PUBLIC (Cover Letter ONLY)
         NON-PUBUC*(Encfoaure),
         Rlds~sOd                           RldsOgcMaiJCentef"                 RldsNripsssripb

RfdsNrrDor1                       'RldsNrrOorlUpb                     Rlukes, NRR

RldsA<;:RS_ManCTR                  JDrake,NRR

SKrepel, NRR                       RldsNrrOe

RldsNrrlADHarrison                 DMorey, NRR

ADAMS Accession Nos.:
         ML19302t!038 .Package

ML192-428695 -Cover Letter

ML19242B64ti'Dlspos1t1on Table

ML19302F448 -Final SE Enclosure               -*c:oncuJTence via email                NRR-106 OFFICE    NRRJDORt/LLPBIPIW!      NRRIDORLA.LPS/t:A        NRR/DSSISNPB* ' NRR/DORlALPB

NAME.     JDrake~                 DHE!rrison               Rl.ukes           DMorey

,DATE      10/29/2019              10/30/2019               1~/2019           10/31/2019'
                                            OFFlCtAL RECORD COPY

0Ff)6blil... ~E EINLY .P~9PR1ETARY INFf?RIIAt=ION

PWROG-16043-NP-A                                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     xi

OFFIOIAL USE ONLY         PROPRiETARY INFORMATION

FINAL SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION

FOR TOPICAL REPQRT pwROG-16043.P, REVISION 2,
                    "pWRQG PROGRAM TO ADDRESS NRC INFORMATION NOTICE 2012-09:
             'IRRADIATION EFFECTS ON FUEL ASSEMBLY SPACER GRID CRUSH STRENGTH'
                              FOR WESTINGHOUSE AND CE PWR FUEL DESIGNS"
                         PRESSURJZED WATER REACTOR OWNERS GROUP (PWROGI

1.0      INTRODUCTION

By letter dated February 1, 2017 (Reference 1), the Pressunzed Water Reactor (PWR) Olmers

Group (PWROG or the applicant), submitted to the U.S Nuclear Regulatory Commission (NRC)
         staff for review licensing topical report (TR) PVVROG-16043-P, Revision 2, "PWROG Program to

Address NRC I nformatlon Notice 2012-09. 'Irradiation Effects on Fuel Assembly Spacer Grid

Crush Strength' for Westinghouse and CE ~ Fuel Designs" (Reference 2, henceforth

referred to as the TR). Subsequent letters dated March 27, 2018, May 15, 2018, and May 15,
         2018 (References 3, 4, and 5, respectively), provided addftlonal Information that supplemented

the information provided in Reference 2. The TR will be used as the basis for determining fuel

assembly characteristics and damping coeffle1ents at End of Life (EOL) conditions for Input into

plant seismic and LOCA analyses that will be performed In accordance with the currant NRC

approved methods descnbed in WCAP-9401-P-A (Reference 6) and CENPD-178(P), Rev. 1-P

(Reference 7), to assess the structural mtegnty of fuel assemblies under faulted condition loads.

2.0      

==BACKGROUND==
Seismic and LOCA events can result In external forces applied to the fuel assemblies

(e.g., shaking and/or vibratory forces) Therefore, applicants must evaluate the fuel assembly

structural response under these conditions to ensure that regulatory requirements are met with

respect to control rod insertablllty and core coola.b1lity. In particular, the spacer gnd

performance 1s assessed to determine ff plastic deformation is expected to occur, and the fuel

assembly vibration behavior Is quanbfied. Most PWR plants currently utilize the NRC approved

testing and analysis methodologies described in References 6 and 7 for Westinghouse and CE

fuel designs, respectively

The NRC reviewed and approved References 6 and 7 based on the regulatory guidance

provided in Appendix A to Section 4.2 of the Standard Review Plan (SRP or Reference 8) One

assumption in the SRP Section 4 2 Appendix A guidance at the time, which Is also In the current

revision from 2007, Is that beginning of life (BOL) is the time at which the crushing load for the

spacer grids would be expected to be at a minimum This assumption was based on the fact

that irradiation tends to cause strengthening In metals and alloys in addition to embrittiement

Other effects that arise due to use In a reactor may include growth, cladding creep, and

corrosion The Increase in strength was expected to more than offset the other effects

associated with irradiated gnds Smee applicants typically verify that the maximum loed

expenenced by the spacer grids dunng LOCA and seismic events will not exceed the crushing

load, use of BOL characteristics was considered to be conservative.

Enclosure

OFFICIAL. Uilii ONL.Y     PROPRlliill\R&#xa5; INFOR.~J'.-AllON

PWROG-16043-NP-A                                                                                          November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                             Xii

OFFICIAL Y&E 0Nb&#xa5;          PROPRUiiTA.R&#xa5; INFOR"AATION

-2-
         0perating expenence that came to light In the mid-200Ds led the NRC staff to question the

assumpbon that the spacer grid structural performance during LOCA and seismic events would

not degrade significantly as a result of lrradratlon. The NRC subsequently issued Information

Notice ON) 2012-09, '1rradiation Effects on Fuel Assembly Spacer Gnd Crush Strength"
         (Reference 9) This IN lsts several factors that can affect the structural strength of the spacer

grids and singles out spacer gnd spring relaxation as one that can have a s1gnlflcant effect on

the fuel assemb",t mechanical characteristics and the spacer grid strength. While no specific

action or response was required as a result of the IN, the NRC indicated that recipients would

be expected to review the information for appllcablllty and consider appropriate acbon to avoid

similar problems.

This TR is the applicant's proposed approach to generically address the issue identified In the

IN for licensees that use Westinghouse or CE fuel. This TR will be used as the basis for

determining fuel assembly characteristics and damping coefficients at EOL conditions for input

Into plant specific seismic and LOC analyses that will be performed In accordance with the

current NRC approved methods descrbed in References 6 and 7, to assess the structural

response of fuel assemblies under faulted condition loads. Crediting flowing water damping

ratios in a S1m1lar manner to the NRC approved still water damping ratios (as descnbed in

References 6 and 7) provides a means for licensees to recover margin lost due to the effect of

spacer grid spring relaxation on the fuel assembly mechanical characteristics.

In summary, the existing NRC approved testing and analysis methodologles will continue to be

used, with all prev10usly established limitations and conditions, however, this TR provides the

basis for determining fuel assembly characteristics and damping coefficients to address

potenbal fuel assembly structural performance ISSUes as a result of irradiation.

3.0      REGULATORY EVALUATION

Trtle 10, "Energy," of the U.S. Code of Federal Regu/ationis (10 CFR), Part 50, "Domestic

Licensing of Production and Utilization Facilities," Section 46, "Acceptance cnterla for

emergency core cooling systems for light-water nuclear power reactors," contains requirements

for the emergency core cooling system (ECCS) at commercial power plants In particular,
         10 CFR 50.46(b)(4) requires that 1c]alculated changes In core geometry shall be such that the

core remains amenable to cooling." Arr/ failure In the structural Integrity of the fuel assembDes

will typically change the core geometry, and the possibility needs to be evaluated.

The regulation at 10 CFR Part 50, Appendix A, "General Design Criteria for Nuclear Power

_f>!a~.~ ~eoei:al Destgn _Critenon (GDC)-10, "Reactor design," states-tlliit "[t]ne-reactor core - .

shall be designed with appropriate margin to assure that specified fuel design limits are not

exceeded durlng ... antle1pated operabonal occurrences

* Within the context of LOCA and

seismic events, this is 1mpllcltly addressed by ensuring adequate core coolablllty.

The regulation at 10 CFR Part 50, Appendix A, GDC 27, "Combined reactivity control systems

capability," states that "IQ he reacbvrty control systerris shall be designed to ... reliably [controij

reactivity changes. " One of the primary reactivity control systems at current WEC and CE

PWR plants Is the rapid insertion of control rods to add sufficient negative reactivity to shut

down the reactor. Reliable operation of this reactMty control system IS condltlonal on the

capabllrty to insert the control rods. Vibrations or structural deformations may impede the

control rod movement and need to be evaluated

OFFISIAb YiE ONL..&#xa5;        PROPRlliTA.R&#xa5; INi;iORMJ\.TION

PWROG-16043-NP-A                                                                                                 November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                    xiii

OFFIOIAL USE ONLY         PROPRIETARY INFORMATION

-3 -
         The regulation at 10 CFR Part 50, Appendix A, GDC 35, "Emergency core cooling," restates the

requirement to maintain adequate emergency core cooling capabi!ty, which can be effected by

the core geometry es discussed m 10 CFR 50 46(b)(4) (see above)
         The regulation et 10 CFR Pert 50, Appendix A, GDC 2, "Design bases for protection against

natural phenomena," requires safety-related structures, systems, and components (SSCs),
         including reactor fuel, to be designed to withstand natural phenomena (such es earthquakes)
         without a loss of capabthty to perform safety functions. This GDC also requires consideration of

"appropriate combinations of the effects of normal end accident conditions with the effects of the

natural phenomena." For example, a LOCA may be caused by a seismic event, so

consideration of the effects from a combination of these two events may be appropriate.

Appendix S of 10 CFR Part 50 end Appendix A of 10 CFR Part 100 provide addibonal guidance

for seismic events, and defines the Safe Shutdown Earthquake (SSE), Operating Basis

Earthquake (OBE), and safety requirements for relevant SSCs In general, cntene should be

defined for each SSC to ensure Its functional cepabilrtles during each event indicated by the

regulatory requirements (typically OBE, LOCA+SSE, and SSE-only, though other combinations

may be considered). These requirements are not expRcftly addressed by the methodologies

submitted for NRC review, however, the overall methodology that PWROG-16043 will

supplement may be used by licensees to demonstrate that these requirements ere met (if

applicable). Therefore, the NRC staff considered the potential mpact of PWROG-16043 on

how these requirements would be met

In summary, the NRC staff used the applicable acceptance cntena defined in Seci:Jon 4.2, Appendix A of the SRP , otherwise known es NUREG-0800 (Reference 8), m its review of the

TR. Since the TR provides an alternate approach to produce parameters for use with existing

methodologies, the scope of the NRC staff review was limited to the tesbng protocols end

analysis approaches descnbed In the TR to develop the aforementioned parameters, and to

verify the appllcablllty of the existing methodologies when usmg the parameters developed with

the new approaches. The primary criteria ere related to ensuring that core coolab1fity and

control rod 1nsertab1lity are maintained

4.0      TECHNICAL EVALUATION

The intent of the TR Is to develop the basis for determining fuel assembly characteristics and

damping coeff1cients at EOL condibons for input into plant specific seismic and LOCA analyses

that wil be performed In accordance with current NRC approved methods m References 6 end

7 by focusing solely on the specific parameters that would be Impacted by the EOL 1SSues

identified in IN 2012-09 (Reference 9). As such, the TR narrowly focuses on three pnmary

parameters*
              1. The allowable gnd impact strength [

2    The fuel assembly modal frequencies [

OFFIGIAL USE ONLY         PROPRIETARY INFORMATION

PWROG-16043-NP-A                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       xiv

OFFIOI-AL USE ONLY         PROPruETARY INFORMATION

-4-
                              ] and

3. The fuel assembly flowing water damping ratio, [

]
         Section 15.02 of the SRP, "Review of Transient and Accident AnalySJs Methods," (Reference

10) provides guidance for review of transient and accident analysis methods This guidance Is

not directly applicable to ttus TR, since the analysls methods described In References 6 and 7 are not being modified, only the amplrlcal determination of key input parameters Therefore, the

NRC staff revteW of the TR only focused on the two specific areas descrfbed in SRP Section

15.0 2 that are relevant to the applicability of the analysis methods when a different approach is

used to develop input parameters, as described below.

1 Evaluabon methodology- the proposed testing and data analysis approach, Including

any potential llmltatlons to their apphcab1lity

2   Uncertainty analysis - the applicant's evaluation and propagation of uncertainties In the

analysis of test data to obtain recommended values for the key parameters.

In addition, the NRC staff considered whether the applicant proV1ded adequate quallty

assurance (QA) and documentabon support for the proposed approach for addressing the EOL

effects on spacer grids This aspect ls not explicitly discussed in detail for this safety evaluabon

(SE) because the documentation of the proposed approach is captured by the documents

reviewed by the NRC dunng an audit dated October 17, 2017 (Reference 11) and that ware

found to have been appropriately summarized or otherwise characterized In the TR. The testing

was performed under the auspices of the same QA program for testing previously performed to

determine the key parameters for BOL gnds and still water damping, which IS acceptable. As

such, the NRC staff acceptance of the adequacy of the appl1eant's test protocol and uncertainty

analyses implicitly includes acceptance of the applicant documentation associated with that

area.

4.1     EOL Grid Simulation

This TR discusses the test protocol used for the characterization of the impact of Irradiation on

the spacer grids SRP Section 4.2 Appendix A (Reference 8) crtes several possible

irradiaoon-related effects relevant to spacer gnds and concludes that the combined impact

_woulctnot be-expected-to lead-to a more conservative result-Thls-loglc-re:rnrn,ainly-on the fact

that the slgnirlcant Increase In yleld strength for the spacer grld matenal will more than offset the

relatively minor effects from the remaining effects. As described in IN 2012-09 (Reference 9),
         operating experience has shown that spacer grid spring relaxation can have a significant

adverse effect on spacer grld strength and fuel assembly mechanical characteristics. [

] Other than grld spring relaxation, the basic assessment in SRP Section 4 2 Appendix A

that 1rradfatlon-related effects are bounded by the Increase in the yleld strength of the spacer

grld matenal continues to be applicable [

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PWROG-16043-NP-A                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     xv

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-5-
                                                     ] As discussed m the previous paragraph, the NRC

staff found that the focus on the grid spring relaxation phenomenon as the key driver for the

non-conservabve behavior identified in spacer grids at EOL relative to SOL 1s appropriate.

However, the materlal and geometry Impact of the thermal relaxation process must be

reasonably similar to the 1rradiabon-mduced impacts that are bemg simulated

] Therefore, the NRC staff requested addrtJonal

lnformabon from the applicant regarding the thermal relaxation procedure used to produce the

simulated EOL gnds. [

] The applicant's response also confirmed that the material structural

characterisbcs of the simulated EOL grids are the same, or slightly conservative, relative to the

SOL gnds.

] There are some situations where a

spacer grid 1s exposed to a strongly non-uniform neutron flux, such as fuel assembly loading

locations at or near the core periphery. The NRC staff asked the applicant to address the

potential Impact on the grid failure mechanism due to non-random gradients in gap size that

may be correlated with steep neutron flux gradients. [

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PWROG-16043-NP-A                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       xvi

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-6- Finally, Secbon 2 1 of the TR described how the target average gap size was determned for a

grven spacer gnd [

]
         Inadequate lnformat10n was given in the TR to deflne the area of appllcabihty for extrapolation of

a given set of PIE data to the general population of EOL gnd spacers of the same design, so the

NRC staff requested that the applicant characterize how PIE data sets are generally demed in

order to achieve their intended purpose.

The applicant responded in Reference 4 with an explanation of the statlst1CSI technique

underlying their determlnabon of a target gap size for the simulated EOL grids [

] this Is a

reasonably conservative approach to ensure that the average gap sizes for the simulated EOL

grids wiB bound the average gap sizes for Irradiated grids.

] The

NRC staff agrees; however, the applicant did not describe how the rod bumups associated wrth

the PIE measurements would be used to deflne the area of apphcab11ity for fuel assemblies

qualified using this approach. In a separate RAI response (RAJ-2, documented In Reference 4),
         the applicant proVJded Information that shows that the variation In gap sizes for varying bum ups

near EOL can be expected to be minor relatJve to the Inherent randomness in gap sizes within a

grid. In add1t10n, the NRC staff noted that the protocol described In Reference 7 for tesbng of

CE design fuel assemblies includes modeling for both BOL and EOL grids [

] Consistent with this assessment, the results from the testing discussed in Sections

42 and 4.3 of this SE show [

]
         Therefore, any venations in bumup for the fuel assemblies used to obtain PIE measurements

relative to the overall populatlon of fuel assemblies being quallfled using this approach would

not result in a significant difference in average gap size, certainly, much less then the inherent

conservatism in the margin between the average measured gap sizes end the target gap size

for the simulated EOL gnds

The NRC staff found that the subject TR described an acceptable approach to produce

simulated EOL grids for testing that accounts for the range of expected variation from 1rradrated

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PWROG-16043-NP-A                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                    xvii

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-7- EOL gnds. [

] As a result, the NRG staff found the proposed approach to

generate S1mulated EOL gnds for use i1 testing in lieu of .-radiated grids to be acceptable

4.2     Spacer Grid Impact Strength

Sections 2.2 and 2.3 of the subject TR discuss the apphcatlon of the approved testing and data

analysis protocol from References 6 and 7 to determine the allowable gnd impact strength for

the simulated EOL grids. In all respects, the testing and data analysis apphcatlons were

consistent with References 6 and 7, [

] The NRG staff understanding of the approval request from the applicant IS that this

addltlonal crltenon was provided merely for demonstration purposes and was not submitted as a

change to how the grid impact strength is determined in Reference 6. In response to a RAI from

the NRG staff (Reference 3), the applicant confirmed that this was the case Therefore, this

application was Judged to be acceptable solely for the purpose of providing a more consistent

basis for comparing P(cnt) for Westinghouse and CE fuel designs

The simulated EOL gnds contain [

] The NRC staff

verified by inspection of the applicant's test documentation that the failure mechanism for the

simulated EOL gnds was the same as that for the BOL gnds Therefore, [

] As discussed in Section 4 2 of this SE, [

The NRC staff verified that the previously approved testing and data analysis protocols in

References 6 and 7 were appropnately applled to the SJmulated EOL gnds In addition, the

NRC staff found reasonable assurance eXJsts that the aforemenboned test protocols remain

applicable to the geometry of the slmulated EOL grids Therefore, the NRC staff found the

approach for determining P(crit) to be acceptable for use in analysis of the simulated EOL grids.

4.3     Fuel Assembly Mechanical Characteristics

Section 3 of the TR d1SCUSses the applicabon of the approved testing and data analysis

protocols in References 6 and 7 to determine the allowable grid Impact strength for the

slmulated EOL gnds. The TR states that "{t]he same test protocol has been previously applied

to current Westinghouse and CE PWR fuel designs for BOL conditions," and that "[tlhe test

protocols are described In NRG-approved TRs .. ." with a citation to References 6 and 7.

Therefore, the TR clearly characterizes the testing procedure for the simulated EOL gnds to be

Identical to the previously approved testing procedure descnbed in References 6 and 7, wrth the

exception that the gnds are simulated EOL grids as discussed in Secbon 4.1 of this SE

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PWROG-16043-NP-A                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                    xviii

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-8- The testing protocols descnbed m References 6 and 7 are pnmanty tests conducted on the

structural members of the fuel assembly and the spacer gnds, with no tests directly Impacting

the fuel rods At BOL, the grid springs exert a fncbonal force on the fuel rods, so the spacer

grids and fuel rods are mechanically coupled to some extent During the fuel assembly vibrabon

tests, the fuel rods contribute to the fuel assembly mechanical performance by virtue of this

mechanlcal coupling. [

4.4      Procedure to Determine Flowing Water Damping Ratios

Section 4 of the TR descnbes the test protocol for determining the fuel assembly flowing water

dampmg ratios and apply them in lieu of preVJOusly approved sbll water damping ratios to

characterize the fuel assembly mechanical behavior during seismic and LOCA events. Since

the damping ratio due to flowing water ls expected to be higher than that for still water, this

approach could help recapture margin lost due to the Impact of grid spacer relaxation on the fuel

assembly stiffness. [

Sections 4.1 through 4.3 describe the test apparatus and data collectlon performed to support

an empmcal determinabon of the flowlng water damping ratios. [

_ .                     _ - ] However, the hydraulic-characteristics for the fuel*assembly

are wel characterized based on pnor testing. [

] Since the

loss coeffle1ents for the fuel assembly designs have been approved by the NRC for use m other

analyses and would not be expected to vary significantly as a result of the use of slmulated EOL

grids, this approach for determining flow velocities through the fuel assembly is acceptable.

The existing test protocols, most notably the Reference 7 protocol for CE fuel, [

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PWROG-16043-NP-A                                                                                          November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       xix

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-9-
                    ] Testing performed on stmllar fuel assembly designs using a range of different

approaches, as documented in References 14 and 15, yield consistent results. [

] This shows that the proposed approach

discussed in this TR yields results consistent wrth what was approved 1n References 13 and 15 (Reference 14 was incorporated in the approved TR represented by Reference 13).

The flowing water damping rabo correlation was developed based [

] Therefore, there will be no inconsistency in the application of damping ra,.t1os

for fuel assemblles at different bumup conditions.

Based on the data collected from the tests, a damping rabo was determined for each      test based

on classical vibration theory [

] Section 4 5 of the TR presents results from the tests. One of the most important

conclusions that can be observed directly from the test results is that [

] Since the use of

lower damping ratios In developmg the correlation IS conservative, this was an acceptable

choice to make

Section 4 6 of the TR discusses the data analysis approach used to determine bounding

correlabons for each fuel assembly design. This approach can be summarized thus: [

] The overall approach appears to capture the relevant dependencies, however, there Is no propagation of the uncertainbes due to scatter in data through the steps noted

above [

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PWROG-16043-NP-A                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                          xx

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-10-
         The applicant responded in Reference 5 wrth information Indicating that the fitting approach

used to determl'le the bounding curve was fundamentally a best estimate approach to derive

the 600 &deg;F curve based on the selected data set [

Finally, Section 4.7 proposes use of a flowing water damping ratio correlation based on the

[             ] fuel assembly design as a generically bounding correlation that may be used wrth

any fuel assembly design wrthout further jusbfication. The procedure discussed above may be

used to develop fuel assembly design specific correlations, but the [                 ] correlation JS

proposed for use as a bounding curve for all Westinghouse and CE fuel designs The

Justification provided is that the [     ] fuel assembly design proposed for the [               ]
         reference plant contains a number of Slg!Jificant design differences, but test results show that

the flowing water damping ratio is very similar to the [               ] fuel. The CE fuel design

tested had [

This bahavlor Is bounded by the [                ] correlation, so this 1s acceptable. However, [

] Therefore, the

slmilanty in results Is not surprising

In order to establish that the proposed correlation can be used as a genenc bounding curve, Its

apphcab1lrty must be lmlted to spacer grids wrth very similar geometry charactenstics This Is

accomplished via a condition to the TR. Information submitted In References 14 and 15 provide

Information for other PWR fuel assembly designs that suggests that, In fact, the [

As long as the geometry characteristics of the spacer gnds associated with a different fuel

assembly do not differ significantly from the [                            ], the NRC staff fnds that

reasonable assurance exists that other fuel assembly designs will have flowing water damping

ratios near or above the proposed bounding curve. The proposed application Includes use of a

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PWROG-16043-NP-A                                                                                               November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       xxi

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- 11 -
         minimum value for the analysls duration rather than a more rea6stlc average value, which

incorporates some addrtJonal conservatism that offsets the potential for slightly lower flowing

water damping ratios for some fuel assembly designs relative to the proposed bounding curve.

Based on the Information provided m the TR, as supplemented by responses to requests for

additional lnformatton from the NRC staff, the testing protocol and data analysis descnbed to

determine appropriate flowing water damping ratios were deterrrnned to be appropriate for their

Intended purpose. In addit1on, [

] This latter condition was captured m Section 5.0.

4.5      Analytical Application of the Flowing Water Damping Ratios

Sections 4 8 and 4.9 of the TR describe when and how the flowing water damping ratios can be

utilized In seismic and LOCA analyses, respectively. The primary parameter used to establish

the appropriate value for the flowing water damping ratio IS the fluid velocity through the fuel

assembly. For a given plant, this parameter Is directly correlated with the core flow. Therefore, the d1scuss1on in the TR pnmanly focuses on the characterization of a bounding core flow for

any given time of Interest dunng the event being analyzed. Once an appropriate value Is

determined, then plant-specific informabon can be used to establish an appropriate flow velocity

to use wrth the flowing water dampr,g ratio correlation. [

] In general, since lower flow velocrties result m lower flowing water

damping ratJos, any factor that may lead to a reduction in the core flow rate will provide more

conservative results. For a given analysis, [

For the seismic analysis, two key assumpbons are made to minimize the total core flow. First,
         [

Secondly, [

]
* At this*tlme, the flowing water damping ratio will be at a minimum, and

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PWROG-16043-NP-A                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     xxii

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-12- lower than the average flowing water damping ratio for the interval Smee these assumptions

both act to minimize the flowing water damping ratio, they are conservative

For the LOCA ana~is, the core flow rates are to be obtained directly from the LOCA analyses, as long as axial flow ls maintained. [

] As a result, the NRC staff finds that the LOCA analysis conditions are an

acceptable source for a bounding core flow rate for the purpose of determining flowing water

damping ratios.

A second !imitation of the flowing water damping ratios Is that the data used as a basis for the

correlation were based on smgle phase liquid flow through a fuel assembly. The condrbons

under which the flowing water damping ratios are expected to be credited-seismic events and

the first -1 second of a LOCA event-are not expected to involve two phase flow in the core.

However, the TR does not explicil:ly limit the use of flowing water damping ratios to single phase

flow conditions, so a hmitatton was a,cluded m Section 5 0 to ensure that, if credit for flowing

water damping 1s apphed to condrbons that deviate from expectations, the correlation will not be

used outside the bounds of Its applicability.

The NRC approval of Reference 13 included review of Information demonstrating that the

Westinghouse models were capable of capturing the dynamic behavior of fuel assemblles for

pluck response Inside a flow loop, for the Vibration range of Interest Since the flowing water

damping ratios are very similar for the RFA/RFA-2 curves being proposed for use as a bounding

curve for all fuel assembly designs and the Reference 13 fuel design contained a similar spacer

grid design, this flndmg 1s appllcable to the subject LTR as well. However, without further

validation, the dynamic models cannot be assumed to maintain reasonable accuracy for

damping ratios that go slgmflcantly beyond the current area of applicability. Therefore, any use

of damping ratios signrticantly higher than the proposed bounding curve must be supported by a

demonstration that the analytical models remain valid for the higher damping regime A

limrtabon was included m SectJon 5 0 to ensure that this potential limitation of the analytical

models Is addressed, If necessary

The guidance provided In the TR to credit flowing water damping ri seismic and LOCA analysis

was reviewed by the NRC staff and determ lned to produce acceptably conservative results for

the expected analysis conditions. Therefore, the NRC staff finds the proposed apphcatlon of

flowing water damping credit for evaluation of fuel assembly mechanical behavior during

___ ~e~lf ~ng LQCA e_vents to be_acceptable.           - - -- -
          4.6      Legacy Issues

There are a number of potential Issues with the previously approved methodologies descnbed in

References 6 and 7. These Issues did not exist at the time that the methodologies In

References 6 and 7 were approved, however, more recent fuel assembly designs have

Incorporated features such as thinner spacer gnd straps that may undergo more plastic

deformation prior to failure. The NRC staff has not retroactively required Dcensees to address

them based on the inherent conservatism within the previously approved methodologies and

typical margins for llcensing seismic analyses. However, the potential use of flowing water

damping credit represents a more reallstic O.e., less conservative) approach. As such, licensees should address the following Issues before they reduce conservatism in their licensing

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PWROG-16043-NP-A                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     xxiil

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- 13 -
         basis analyses that utilize the methodologies from References 6 and 7. In some cases, these

issues have already been addressed for eXJsling fuel assembly designs

In order to ensure that the overall analysis remains conservabve, a limitation was Included in

Section 5 0 to restrict use of flowing water damping credit unless mformatJon 1s provided to

address the above Issues. The !Imitation can be resolved by providing information to

demonstrate that any predicted loads on the guide tubes and spacer grld cage remain within the

elastic regton This ensures that (1) through (3) are directly satisfied, and impllcltly ensures that

(4) is met by ensunng that safety related components are capable of perfonnmg their safety

function under the combined effects of SSE and the accident loads for which their function is

required.

As d1SCussed above, the NRC staff identified some technical ISSUes that are not explicitly

addressed by the currently approved methodology They may have been addressed for current

fuel assembly designs, however, the use of a more realistic flowing water damping ratio

represents a reducbon in conservatism for the dampng ratio approach relative to the previously

approved approach Therefore, the NRC staff 1s 1mposmg limitations and conditions to ensure

that the overall conservatJsm of the analysis Is acceptable.

s.o      LIMITATIONS ANP CQNPITJQNS

Some limitations and conditions are necessary to ensure that the approaches d15cussed 1n the

TR Is llmited to the applications for which it 1s valid, and to ensure that the overall analysis

methodology remains conservative. These llmltabons and condibons are listed below

1. [

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PWROG-16043-NP-A                                                                                           November 2019 Revision 2*

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                      XXlV

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-14-
          6.0      CONCLUSIONS

The applicant suomtted a TR that will be used as the basis for determining fuel assembly

characteristics and damping coefficients at EOL conditions for input nto plant specific seismic

and LOCA analyses that will be performed in accordance wih the current NRC approved

methods as described 1n References 6 and 7, to assess the structural integrity of fuel

assemblies under faulted condition loads. The following conclusions are provided here in

summary as they apply to ncensees who may want to adopt the TR to address the effect of

Irradiation on the mechanical properties of fuel assemblies.

Since the TR is not proposing any change to the preVJOusly approved testing and analysis

methods for seismic and LOCA events, the NRC staff performed a graded review of the TR that

took into consideration the fact that most aspects of the methods that this TR Is intended for use

with have already been addressed as part of prior NRC reviews The applicant requested

approval of seven specific Items identified in Section 1.4 of the TR

The NRC staff examined the proposed approach to produce simulated EOL spacer grids and

determined that the simulated EOL spacer grids would adequately capture the non-conservative

impacts due to irradiation. The staff also determined that the [

_ __ _ _ _ _         ______ . _ _ _ _                    _ ---] The NRG-staffs-
       -findings were based primanly on the specific material type (zirconium alloy) and general grid

design covered by the informat10n presented in the TR, [

The use of flowing water damping ratios Is not an entirely new approach to develop more

realistic parameters that help mitigate the impact of vibratory loads, because rt is slmllar to what

was approved by the NRC for the AP1000 (Reference 13). However, this Is the first time that it

is beng applied more generically to Westinghouse and CE fuel In particular, the applicant 1s

proposing the use of a bounding curve that is applicable to all spacer grids used in

Westinghouse and CE fuel, along with a general approach that can be used to generate fuel

design specific curves The staff reviewed the information submitted In the TR along with

responses to requests for additional Information, and determined that the approach was

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PWROG-16043-NP-A                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                  XXV

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- 15 -
         appropnate for both purposes. Addmonally, the guidance proV1ded for utllizatlon of flowing

water damping ratios in selSITlic and LOCA analyses was found to be appropnate for their

Intended use, with the hmitabons that. (1) the flowing water damping ratios are only valld for

single phase liquid flow, and (2) the dynamic models used to predict the fuel assembly response

under Vibratory and damping loads must be verified to remain reasonably accurate for higher

damping regimes (Limitations and Conditions 2 and 4)
         The NRC staff also acknowledged some legacy issues that have not previously been addressed

by the NRC staff due to their low nsk significance, based on the Inherent conservabsms within

the analysis methods descnbed in References 6 and 7. Consequently, the NRC staff finds that

any reduction in analytical conservatism should not be made Without addressing these legacy

issues, as d1scllSS8d In Section 4.6. The use of flowing water damping ratios represents one

such reducbon m analybcal conservatism, therefore, a condition for use of the new damping

ratios Is that the legacy Issues need to be addressed (Limitation and Condition 3).

In summary, the NRC staff finds that the information provided in the TR and responses to NRC

staff RAls adequately demonstrates that the proposed approach to address EOL effects on

spacer grids and to recover margin through credit for flowing water damping are acceptable for

use with existing methods that the NRC has previously found to be acceptable for analysis of

fuel assembly structural behavior during seismic and LOCA events The NRC staff approval of

th13 TR extends to all West~ghouse and CE fuel designs, contingent on adherence to the

limitations and condibons set forth In Section 5.0.

7.0      REFERENCES

PWROG letter OG-17-12, Jack Stnngfellow, Chief Operating Officer and Chairman, PWROG, to USNRC document control desk, re: "Submittal of PWROG-16043-P, Revision

2, 'PWROG Program to Address NRC Information Notice 2012-09: 'irradiation Effects on

Fuel Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
              PA-ASC-1169R2," February 1, 2017 (ADAMS Accession No. ML 170396050)
         2    PWROG-16043-P, Revlslon 2, "P\NROG Program to Address NRC lnformabon

Notice 2012-09: 'lrradiabon Effects on Fuel Assembly Spacer Grid Crush Strength' for

Westinghouse and CE PWR Fuel Designs," January 2017 (ADAMS Package Accession

No. ML 17039BOB1)
         3    PWROG letter OG-18-62, Jack Stnngfellow, Chief Operating Officer and Chairman, PWROG, to USNRC document control desk, re: "Transmittal of the Response to Request

for Addibonal Information, RAls 4 and 5 Associated with PWROG-16043, Revision 2,
              "PWROG Program to Address NRC Information Notice 2012-09* 'Irradiation Effects on Fuel

Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
              PA-ASC-1169," March 27, 2018 (ADAMS Accession No. ML 181 OOA053)
         4. PWROG letter OG-18-104, Jack Stnngfellow, Ch10f Operating Officer and Chairman, PWROG, to USNRC document control desk, re: "Transmittal of the Response to Request

for Add1tlonal Information, RAls 1, 2, and 3 Associated with PWROG-16043, Revision 2,
              "PWROG Program to Address NRC Information Notice 2012-09. 'lrrad1abon Effects on Fuel

Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
              PA-ASC-1169," May 15, 2018 (ADAMS Accession No ML 181436462)
                              Ol=l=ICIAb blSE ONbY     PROPRIETARY INFORMATION

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-16-
         5. PWROG letter OG-18-105, Jack Strlngfellow, Chief Operabng Officer and Chairman, PWROG, to USNRC document control desk, re: "Transmittal of the Response to Request

for Addibonal lnformabon, RAJ 6 Associated with P~OG-16043, Revis10n 2, "PWROG

Program to Address NRC Information Notice 2012-09: 'lrradlabon Effects on Fuel Assembly

Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,' PA-ASC-1169,"
             May 15, 2018 (ADAMS Accession No. ML 18144A760)
         6. WCAP-9401-P-A, Revision 0, 'Venficatlon Testing and Analysis of the 17x17 Optimized Fuel

Assembly," September 1981 (ADAMS AcceSSJon No. ML090280466 (Non-Publicly

Available))
         7   CENPD-178{P), Revision 1-P, "Structural Analysls of Fuel Assembhes for Seismic & LOCA

Loading," August 1981 (ADAMS Accession No ML 14122A086 (Non-Publicly Available))
         8   NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear

Power Plants: LWR Edition," Section 4.2, Revision 3, "fuel System Design," March 2007 (ADAMS Accession No. ML070740002)
         9. NRC Information Notice 2012-09, "Irradiation Effects on Fuel Assembly Spacer Grfd Crush

Strength,* dated June 28, 2012 (ADAMS Accession No. ML 113470490)
         10. NUREG-0800, "Standard ReV1ew Plan for the Review of Safety Analysis Reports for Nuclear

Power Plants* LWR EdltlOn," Section 15.02, ReV1s10n 0, "ReVJeW of Trans10nt and Accident

Analysi:, Methods," March 2007 (ADAMS ACC0SS1on No. ML070820123)
         11. NRC letter from Brfan Benney, Senior Project Manager, Licensing Processes Branch, Division of Policy and Rulemakmg, USNRC, to Jack Stringfellow, Chief Operabng Officer

and Chairman, PWROG, re. "Summary Report for the October 17, 2017, Audit m Support of

the ReVlew of PWROG-16043-P, Revision 2, ''PVI/ROG Program to Address NRC

Information Notice 2012-09: 'Irradiation Effects on Fuel Assembly Spacer Grid Crush

Strength' for Westinghouse and CE PWR Fuel Designs," January 8, 2018 (ADAMS

)-
             Accession No. ML 17326A003)
         12 Framatome ANP, Inc. letter NRC'()3 051, James F Mallay, Director, Regulatory Affairs, Framatome ANP, Inc., to USNRC document control desk, re. "Closure of lntenm

____ __B~RQrt Q2~. *~pa~er_Gljg_Q_(YSt:l_SJ!:engtti_-~ffects of ln:ad_1!rt1Q__n,'" AugU&sect;t_&sect;, 20Q3 (ADAMS Accession No ML032240425)
         13. WCAP-17524-P/NP-A, ReV1slon 1, "AP1000 Core Reference Report," May 2015 (ADAMS

Accession No. ML15180A175)
         14. Westinghouse letter LTR-NRC-13-26, James A. Greshman, Manager, Regulatory

Compliance, Westinghouse Electric Company, to USNRC document control desk, re: "Supplemental Information on End-of-Life Selsmlc/LOCA calculatlons for the AP1000
              Pressunzed Water Reactor (Proprietary/Non-Propnetary)," April 30, 2013 (ADAMS

Accession No. ML 13128A017)
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PWROG-16043-NP-A                                                                                       November 2019 Revision 2

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- 17 -
         15 Framatome Inc report ANP-10337P-A, Revision 0, "P\11/R Fuel Assembly Structural

Response to Externally Applied Dynamic Excitations," Aprll 2018 (ADAMS Package

Accession No. ML 18144A816)
         Prlnclpal Contributor: Scott Krepel, NRR/DSS/SNPB

Date. May 17, 2019 OFFIGIAL U6E ONLY      PROPruETARY INFORMATION

PWROG-16043-N P-A                                                                           November 2019 Revision 2

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PWR Owners Group

United States Member Participation* for PA-ASC-1169, Revision 4 Participant

Utility Member                            Plant Slte(s)         Yes     No

Ameren Missoun                         Callaway 0N)                           X

American Electnc Power                 D C. Cook 1 & 2 (W)                    X

Arizona Public Service                 Palo Verde Unit 1, 2, & 3 (CE)         X

Millstone 2 (CE)                               X

Dominion Connecticut

Millstone 3 (W)                        X

North Anna 1 & 2 (W)                   X

Dominion VA

Surry 1 & 2 0N)                        X

Catawba 1 & 2 (W)                              X

Duke Energy Carolinas                  McGuire 1 & 2 (W)                              X

Oconee 1, 2, & 3 (B&W)                         X

Robinson 2 0N)                                 X

Duke Energy Progress

Shearon Harris (W)                             X

Entergy Palisades                      Palisades (CE)                                 X

Entergy Nuclear Northeast              Indian Point 2 & 3 (W)                 X

Arkansas 1 (B&W)                               X

Entergy Operations South               Arkansas 2 (CE)                        X

Waterford 3 (CE)                       X

-                                   - - -Bra1dwoocL'i &-2-0:N">--------- ~X

Byron 1 & 2 (W)                        X

Exelon Generation Co. LLC              TMI 1 (B&W)                                    X

Calvert Cliffs 1 & 2 (CE)                      X

Ginna 0N)                                      X

Beaver Valley 1 & 2 0N)                        X

FirstEnergy Nuclear Operating Co.

Davis-Besse (B&W)                              X

St Lucie 1 & 2 (CE)                            X

Turkey Point 3 & 4 (W)                         X

Florida Power & Light\ NextEra

Seabrook (W}                                   X

pt Beach 1 & 2 0N)                             X

Luminant Power                         Comanche Peak 1 & 2 0N)                X

'PWROG-16043-NP-A                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                        xxix

Omaha Public Power District                     Fort Calhoun (CE)                                      X

Pacific Gas & Electric                          D1ablo Canyon 1 & 2 (W)                         X

PSEG - Nuclear                                  Salem 1 & 2 (W)                                        X

South Carolina Electric & Gas                   V.C Summer (W)                                  X

So. Texas Project Nuclear Operating Co.         South Texas ProJect 1 & 2 (W)                          X

Farley 1 & 2 (W)                                X

Southern Nuclear Operating Co.

Vogtle 1 & 2 (W)                                X

Sequoyah 1 & 2 (W)                                     X

Tennessee Valley Authority

Watts Bar 1 & 2 (W)                             X

Wolf Creek Nuclear, Operating Co.               Wolf Creek (W)                                  X

Xcel Energy                                     Prairie Island 1' & 2 (W)                              X

Note*: Project participants as of the date the final deliverable was completed On occasion, additional

members will join a project Please contact the PWR Owners Group Program Management

Office to verify participation before sending this document to participants not listed above.

- -, - -- - -
              PWROG-16043-NP-A                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           XXX

PWR Owners Group

International Member Participation* for PA-ASC-1169, Revision 4 Participant

Utility Member                                      Plant Slte(s)               Yes       No

Asco 1 &2 (W)                                          X

Asoc1ac16n Nuclear Asc6-Vandell6s

Vandellos 2 (W) *                                      X

AxpoAG                                            Beznau 1 & 2 (W)                                       X

Centrales Nucleares Almaraz-Trillo                Almaraz 1 & 2 (W)                             X

EDF Energy                                        Sizewell B (W)                                         X

Doel 1 , 2 & 4 (W)                                     X

Electrabel

Tihange 1 & 3 (W)                                      X

Electncite de France                              58 Units                                      X

Eletron uclear-Eletrobras                         Angra 1 (W)                                            X

Eskom                                             Koeberg 1 & 2 (W)                                      X

Hokkaido                                          Tomari 1, 2 & 3 (MHI)                                  X

Japan Atomic Power Company                        Tsuruga 2 (MHI)                                        X

Mihama 1, 2 & 3 (W)                                    X

Kansai Electric Co., LTD                          Ohi 1, 2, 3 & 4 (W & MHI)                              X

Takahama 1, 2, 3 & 4 (W & MHI)                         X

Kori 1, 2, 3 & 4 (W)                                   X

Hanbit 1 & 2 (W)                                       X

Korea Hydro & Nuclear Power Corp.                                                                 '
---- ------                    - - - - - - - - -- -Hanbit-3,-4,5-&-6-(GE-)--- --*-- - **   -- -----    -X-
                                                   Hanul 3, 4 , 5 & 6 (CE)                                X

Genkai 1, 2, 3 & 4 (MHI)                               X

Kyushu

Sendai 1 & 2 (MHI)                                     X

Nukleama Electrama KRSKO                          Krsko (W)                                              X

RinghalsAB                                        Ringhals 2, 3 & 4 (W)                                  X

Shikoku                                           lkata 1, 2 & 3 (MHI)                                   X

Taiwan Power Co.                                  Maanshan 1 & 2 (W)                                     X

Note*. Project participants as of the date the final deliverable was completed On occasion, additional

members will join a project Please contact the PWR Owners Group Program Managem~nt

Office to verify participation before sending this document to participants not listed above.

PWROG-16043-NP-A                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                       xxxi

TABLE OF CONTENTS

LIST OF TABLES .................................................................................................................... xxxii

LIST OF FIGURES ................................................................................................................ xxxiii

EXECUTIVE SUMMARY ..................................................................................................... XXXIV

1     INTRODUCTION AND ASPECTS REQUESTED FOR APPROVAL .............................. 1-1
      1.1   INTRODUCTION .............................................................................................. 1-1
      1.2   OVERVIEW OF REPORT CONTENTS ............................................................ 1-2
      1.3   APPLICABILITY OF THIS REPORT .................................................................. 1-2
      1.4   REQUEST FOR NRC APPROVAL ..................................................................... 1-3
      1.5   REFERENCES ................................................................................................. 1-3
2     ALLOWABLE GRID IMPACT STRENGTH AT EOL CONDITIONS ................................ 2-1
      2.1   GRID CELL SIZES AT EOL CONDITION ........................................................... 2-1
      2.2   ALLOWABLE GRID IMPACT STRENGTH ........................................................ 2-2
      2.3   GRID IMPACT TESTS AT EOL CONDITION ..................................................... 2-3
      2.4   REFERENCES ................................................................................................... 2-6
3     FUEL ASSEMBLY DYNAMIC CHARACTERISTICS AT EOL CONDITIONS ................. 3-1
      3.1   EOL FUELASSEMBLY MECHANICAL TESTS .................................................. 3-1
      3.2   REFERENCES ................................................................................................... 3-4
4     FUEL ASSEMBLY FLOWING WATER DAMPING ....................................................... .4-1
      4.1   DESCRIPTION OF FLOWING WATER DAMPING TESTS .............................. 4-2
      4.2   BUNDLE FLOW RATE ....................................................................................... 4-4
      4.3   FUEL ASSEMBLY FLOWING WATER DAMPING TEST CONDITIONS ............ 4-6
      4.4   FLOWING WATER DAMPING CALCULATION METHOD ................................. 4-6
      4.5   FUELASSEMBLY FLOWING WATER DAMPING TEST RESULTS ................. .4-9
      4.6   FLOWING WATER DAMPING RATIO ............................................................. 4-12
      4.7   BOUNDING DAMPING CURVE ....................................................................... 4-16
      4.8   FLOWING WATER DAMPING CREDIT WITH REACTOR COOLANT PUMP

COASTDOWN DURING A SEISMIC EVENT ................................................. .4-19
      4.9   FLOWING WATER DAMPING CREDIT FORA LOCA EVENT ........................ 4-21
      4.10 REFERENCES .................................................................................................4-21
5     CONCLUSIONS ........................ : ................................................................................... 5-1 PWROG-16043-NP-A                                                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                  xxxii

LIST OF TABLES

.TABLE 2-1. RFA-2 MID GRIDS TEST RESULTS FOR PENDULUM GRID IMPACT

COMPARISONS OF AT BOLAND EOL CONDITIONS_ ........................................ 2-4
_TABLE 2-2. CE16NGF MID GRIDS TEST RESULT COMPARISON_ ...................................... 2-6
_TABLE 3-1. MODAL FREQUENCIES OF RFNRFA-2 FUEL ASSEMBLY_ .............................. 3-3
_TABLE 3-2. MODAL FREQUENCIES OF CE16NGF FUELASSEMBLY_ ................................ 3-4
.TABLE 4-1. COMPARISON OF TEST ASSEMBLY GEOMETRIC FEATURES.................... .4-16 PWROG-16043-NP-A                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                 xxxiii

LIST OF FIGURES

..FIGURE 2-1. SUMMARY OF MID GRID CELL TO ROD GAP PIE DATA, RFA-2.. ................... 2-2
_FIGURE 2-2. PENDULUM GRID IMPACT TEST APPARATUS_ ............................................. 2-4
_FIGURE 2-3. LONG HYDRAULIC GRID IMPACT TEST APPARATUS_ ................. , ................ 2-5
_FIGURE 2-4. ONE-SIDED IMPACT GRID STRENGTH APPARATUS_ .................................... 2-5
_FIGURE 3-1. TYPICAL FUEL ASSEMBLY LATERAL VIBRATION TEST SETUP_ .................. 3-3
..FIGURE 4-1. TEST LOOP PRESSURE VESSELAND PLUCK MECHANISM. ...................... .4-3
.FIGURE 4-2. FLOW HOUSING AND PRESSURE VESSEL (TOP VIEW)_ .............................. 4-4
..FIGURE 4-3. FUEL ASSEMBLY FREE BODY DIAGRAM_ ...................................................... 4-4
..FIGURE 4-4. RFA/RFA-2 BUNDLE FLOW RATE TEST RESULTS_ ........................................4-5
_FIGURE 4-5. CE16NGF BUNDLE FLOW RATE TEST RESULTS_ ........................................ .4-6
..FIGURE 4-6. ILLUSTRATION OF TWO SUCCESSIVE AMPLITUDE METHOD_ ................... .4-7
.FIGURE 4-7. FUELASSEMBLY DECAY MOTION IN FLOWING WATER ............................ .4-8
_FIGURE 4-8. RFA/RFA-2 DAMPING RATIOS IN STILLAND FLOWING WATER AT 100.&deg;F-4-10
_FIGURE 4-9. RFA/RFA-2 DAMPING RATIOS IN STILL AND FLOWING WATER AT 200.&deg;F.4-10
_FIGURE 4-10. RFA/RFA-2 DAMPING RATIOS IN STILLAND FLOWING WATER AT 300.&deg;F.. 4-
             11
..FIGURE 4-11. RFA/RFA-2 DAMPING RATIOS IN STILLAND FLOWING WATER AT 380.&deg;F .. 4-
             11
..FIGURE 4-12. RFA/RFA-2 DAMPING VS BUNDLE VELOCITY_ ........................................... 4-12
..FIGURE 4-13. CE16NGF DAMPING VS BUNDLE VELOCITY_ ............................................ 4-13
 .FIGURE 4-14. RFA/RFA-2 DAMPING VS DENSITY_ ...........................................................4-14
.FIGURE 4-15. RFNRFA-2 DAMPING RATIO VS BUNDLE VELOCITY AT 600&deg;F_ ............... 4-15
_FIGURE 4-16. CE16NGF DAMPING RATIO VS BUNDLE VELOCITY AT 600&deg;F_ ................. 4-15
_FIGURE 4-17. DAMPING RATIO VS BUNDLE VELOCITY CURVE COMPARISON._ .......... 4-16
_FIGURE 4-18. BOUNDING DAMPING RATIO VS BUNDLE VELOCITY CURVE ................ 4-18
.FIGURE 4-19. TYPICAL RCS PUMP COASTDOWN CURVES_ .......................................... .4-19
_FIGURE 4-20. TYPICAL 3-LOOP RCS PUMP COASTDOWN CURVE.. ................................ 4-20
_FIGURE 4-21. DAMPING RATIO VS. COASTDOWN TIME FOR A TYPICAL

WESTINGHOUSE 3-LOOP UNIT_ ..................................................................4-20
PWROG-16043-NP-A                                                                           November 2019 Revision 2

VVESTINGHOUSE NON-PROPRIETARY CLASS 3                                               xxxiv

===EXECUTIVE SUMMARY===
United States (U.S.) Nuclear Regulatory Commission (NRC) Information Notice (IN) 2012-09,
"Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength," was issued in June 2012.

The IN discusses that based on recent operating experience, the crush strength of the fuel

assembly spacer grids may decrease during the life of a fuel assembly. NUREG-0800,
"Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants:
LWR Edition (SRP) Section 4.2, "Fuel System Design," Appendix A, "Evaluation of Fuel

Assembly Structural Response to Externally Applied Forces," infers that fuel spacer grid

strength only needs to be considered at Beginning-Of-Life (BOL) conditions with respect to

evaluating fuel structural integrity. The Westinghouse methodologies for assessing the structural

integrity of fuel assemblies under faulted condition loads (seismic and LOCA) are contained in

two NRG-approved topical reports (TRs), WCAP-9401-P-A, "Verification Testing and Analyses of

the 17X17 Optimized Fuel Assembly/ and CENPD-178-P, Rev. 1-P, "Structural Analysis of Fuel

Assemblies for Seismic and Loss of Coolant Accident Loading." The plant-specific analyses are

currently performed with fuel assembly spacer grid characteristics at BOL conditions based on

===SRP Section 4.2, Appendix A===
This TR addresses the issue identified in NRC IN-2012-09 by applying the approach that was

used to address the EOL effects for the AP1000.1 Core Reference Report APP-GW-GLR-153, Rev. 1, "AP1000 Core Reference Report". The tests utilized the NRG-approved methodologies

contained in WCAP-9401-P-A and CENPD-178-P, Rev.1-P with simulated EOL grids.

Additionally, flowing water damping testing was performed and flowing water damping within the

NRG-approved methodologies can be credited consistent with the approach used to address

EOL effects in the AP1000 Core Reference Report that was approved by the NRC. Testing was

performed on two fuel designs, the Westinghouse 17x17 Robust Fuel Assembly-2 and the

Combustion Engineering (CE) CE16NGF' 1 , and is discussed in this TR.

This TR discusses the applicability for determining fuel assembly characteristics and damping

~cj~n~-~t ~OL C_<?!1_ditio~-~ a~d -~~c!~ecis for whi~h Ni3-C ~r:,proval ls requested. "fhis T~
does not revise and or modify the current grid and fuel assembly test methods, or the fuel

assembly seismic and LOCA analysis methodologies, processes and codes that were

previously approved by NRC.

1 AP1000 and CE16NGF are a trademark or registered trademark of Westinghouse Electric Company LLC, rts Affiliates

and/or its Subsid1anes in the United States of America and may be registered in other countries throughout the world. All

rights reserved. Unauthorized use 1s strictly prohibited. Other names may be trademarks of their respective owners.

PWROG-16043-NP-A                                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 1-1
1        INTRODUCTION AND ASPECTS REQUESTED FOR APPROVAL

1.1      INTRODUCTION

United States (U.S.) Nuclear Regulatory Commission (NRC) Information Notice (IN) 2012-09,
"Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength, was issued in June 2012 D

(Reference 1-1). The IN discusses that based on recent operating experience, the crush

strength of the fuel assembly spacer grids may decrease during the life of a fuel assembly.

NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear

Power Plants: LWR Edition (SRP) Section 4.2, "Fuel System Design, n Appendix A, "Evaluation

of Fuel Assembly Structural Response to Externally Applied Forcesn (Reference 1-2), infers that

fuel spacer grid strength only needs to be considered at Beginning-Of-Life (BOL) conditions with

respect to evaluating fuel structural integrity. The Westinghouse methodologies for evaluating

the structural integrity of fuel assemblies under faulted condition loads (seismic and LOCA) are

contained in two NRG-approved topical reports (TRs), WCAP-9401-P-A, "Verification Testing

and Analyses of the 17X17 Optimized Fuel Assembly," and CENPD-178-P, Rev. 1-P, "Structural

Analysis of Fuel Assemblies for Seismic and Loss of Coolant Accident Loading" (References 1-3 and 1-4, respectively). The plant-specific analyses are currently performed with fuel assembly

spacer grid characteristics at SOL conditions based on SRP Section 4.2, Appendix A.

For a fuel assembly with zirconium alloy grids, the irradiation effects due to rod diameter creep, grid spring relaxation and grid growth, also called the End-of-Life (EOL) conditions, can reduce

grid spring preload, and allow small gaps between the rod and grid supports to form. The

irradiation effects can reduce the zirconium alloy grid impact strength, and also, reduce the fuel

assembly bundle stiffness and natural frequencies The irradiation effects could potentially

increase the grid impact loads and fuel assembly component stresses during seismic and LOCA

events To address this issue, fuel assembly damping in flowing water can be used to offset the

EOL irradiation effects.

To address NRC IN 2012-09 for the Westinghouse and Combustion Engineering (CE) PWR fuel

designs, the PWROG Analysis Committee and Westinghouse proactively initiated a program, the result of which are documented in this topical report. This topical report is based on the

NRG-approved approach used for the AP1000 Core Reference Report (Reference 1-5) and

includes testing of Westinghouse and Combustion Engineering (CE) PWR fuel designs at

simulated EOL conditions.

The topical report addresses three key items with respect to evaluating the structural integrity of

fuel assemblies under faulted condition loads:
  [                                                                                               J

PWROG-16043-NP-A                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                  1-2
  1.2      OVERVIEW OF REPORT CONTENTS

In this TR (PWROG-16043-P), the testing of two fuel designs-is discussed. These were the

Westinghouse 17x17 Robust Fuel Assembly-2, herein referred to as "RFA/RFA-2," and the CE

CE16NGF fuel designs.

Sections 2, 3, and 4 of this TR discuss the three key items listed above.

Section 2 discusses the grid strength tests for two types of grids, the RFA/RFA-2 and CE16NGF.

The test setups and methods are based on the NRG-approved test methods discussed in

WCAP-9401-P-A (Reference 1-3) and CENPD-178-P, Rev. 1-P (Reference 1-4).

Section 3 discusses the fuel assembly mechanical tests for two fuel assembly designs, the

RFA/RFA-2 and CE16NGF. The test setups and methods are based on the NRG-approved test

methods discussed in WCAP-9401-P-A (Reference 1-3) and CENPD-178-P, Rev. 1-P

(Reference 1-4).

Section 4 discusses the two fuel assembly flowing water damping tests (for the RFA/RFA-2 and

CE16NGF) that were performed as part of this PWROG program. The test setup, method, and

damping data reduction are consistent with that previously used and approved by the NRG for

addressing the EOL effects for the AP1000 plant (Reference 1-5).

These sections discuss the aspects that have been previously approved by the NRG with

respect to the testing protocols as described in WCAP-9401-P-A (Reference 1-3) and CENPD-
  178-P, Rev. 1-P (Reference 1-4). Test protocol, as used in this TR, includes the test setup, testing, and data reduction. These sections also describe the main aspects of the testing that

are different from what has been previously approved by the NRG for the current Westinghouse

and CE PWR fuel designs. Although these aspects may not have been approved for the current

Westinghouse and CE PWR fuel designs, these Sections describe how they have been

approved for the AP1000 plant as described in Reference 1-5 and how they have been applied

-to ai:fdressl~f2012~09-.-- - - --- -- - -                   - ---                 - -- --- --
  1.3      APPLICABILITY OF THIS REPORT

C

/
   PWROG-16043-NP-A                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 1-3
1.4     REQUEST FOR NRC APPROVAL

This submittal does not revise and or modify the current NRG-approved grid and fuel assembly

test methods, or the fuel assembly seismic and LOCA analysis methodologies, processes and

codes approved by NRG (References 1-3 and 1-4). The purpose of this TR is to only address

the issue identified in NRG Information Notice 2012-09: "Irradiation Effects on Fuel Assembly

===Spacer Grid Crush Strength.n===
           '
NRG approval of the following is requested:
                                                                                                   C

1.5     REFERENCES

1-1: NRG INFORMATION NOTICE 2012-09, "Irradiation Effects on Fuel Assembly Spacer Grid

Crush Strength," June 28, 2012.

1-2: NRG NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for

Nuclear Power Plants: LWR Edition," (SRP) Section 4.2, "Fuel System Design, n Revision 3, March 2007, Appendix A, "Evaluation of Fuel Assembly Structural Response to Externally

Applied Forces."
1-3: WCAP-9401-P-A, "Verification Testing and Analyses of the 17 x 17 Optimized Fuel

Assembly/ August 1981.              .

1-4: CENPD-178-P. Rev. 1-P, "Structural Analysis of Fuel Assemblies for Seismic and Loss of

caolanrAccident loaaing,"Augusf1981.           -     -       -    - *-    - --
1-5* APP-GW-GLR-153, Rev. 1, "AP1000 Core Reference Report,n May 2015.

PWROG-16043-NP-A                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                  2-1
2       ALLOWABLE GRID IMPACT STRENGTH AT EOL CONDITIONS

This section describes the test protocol for determining grid impact strength at EOL conditions.

The test protocol uses Westinghouse and CE PWR Fuel design simulated EOL grids for

determining grid impact strength at EOL conditions. A more detailed description is provided in

the subsequent subsections.

The same test protocol has been previously applied to current Westinghouse and CE PWR fuel

designs for BOL conditions

The test protocols are described in NRG-approved TRs WCAP-9401-P-A (Reference 2-1) and

CENPD-178-P, Rev. 1-P (Reference 2-2).

The main aspects of the testing described in this section that are different from what has been

previously approved by the NRC for current Westinghouse and CE PWR fuel designs are:
   [

Even though these aspects have not been approved for current Westinghouse and CE PWR

l C

fuel designs, they have been approved by the NRC for the AP1000 plant as described in TR

APP-GW-GLR-153, Rev. 1 (Reference 2-3).

For the testing performed ih this program and described in this section, two fuel assembly

designs were used: the Westinghouse RFNRFA-2 and CE16NGF designs.

The results presented in this section are for the purpose of demonstrating the test protocol and

for demonstrating the EOL effects to determine the grid strength and grid impact stiffness at

EOL conditions. The test protocol is applicable to all Westinghouse and CE PWR fuel designs.

----------~----------------------~------
2.1     GRID CELL SIZES AT EOL CONDITION

The grid cell sizes used to simulate the EOL conditions in both the grid impact tests and fuel

assembly mechanical tests are mainly based on PIE cell size data. Both the data average and

the standard deviation are considered when specifying the target cell size for the test grids. The

process of compiling PIE data and specifying target cell size is consistent with that was used for

the AP1000 EOL issue that was previously approved by the NRC (Reference 2-3).

C

PWROG-16043-NP-A                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 2-2 a,c

Figure 2-1. Summary of Mid Grid Cell to Rod Gap PIE Data, RFA-2 a,c

2.2- - -ALLOWABLE GRID IMPACT STRENGTH

The purpose of grid impact testing is to determine the allowable grid impact strength, called

crush load P(crit) in SRP (Reference 2-4). SRP states that "the crushing load P(crit) has been

suitably selected from the load-versus-deflection curves." The allowable grid impact strength is

the maximum grid impact load with small plastic deformation for current Westinghouse and CE

grid designs.

PWROG-16043-NP-A                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                   2-3
[                                                                                                  r  a,c

2.3     GRID IMPACT TESTS AT EOL CONDITION

The same grid strength test procedures are used for both BOL and EOL conditions. The current

Westinghouse test methodologies described in WCAP-9401-P-A (Reference 2-1) and CENPD-
178-P, Rev. 1-P (Reference 2-2) are used except for the preparation for test grids as discussed

herein.

a,c

PWROG-16043-NP-A                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 2-4 FUEL TUBES          BACK

CIRCULATING FAN                   PLATE

DOOR

LOAD CELL

IMPACT BAR

Figure 2-2. Pendulum Grid Impact Test Apparatus

Table 2-1. RFA-2 Mid Grids Test Results for Pendulum Grid Impact Comparisons of at

BOL and EOL Conditions

a,c

For the fuel designs used in CE design cores, the hydraulic long pulse test and drop test are

performed. The hydraulic long pulse and the drop test set ups are shown in Figures 2-3 and 2-4, respectively. Both tests are performed at room temperature and test results are scaled to the

reactor temperature when they are applied in seismic/LOCA analysis. The test procedures and

results application are consistent with CENPD-178-P, Rev. 1-P (Reference 2-2) .

PWROG-16043-NP-A                                                                  November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                          2-5 FUEL ASSEMBLY SECTION    COMPRESSION

SUPPORTED BY END PLATES  LVDTs

STEEl

PLATE

Figure 2-3. Long Hydraulic Grid Impact Test Apparatus

Figure 2-4. One-Sided Impact Grid Strength Apparatus

a,c

PWROG-16043-NP-A                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                2-6 Table 2-2. CE16NGF Mid Grids Test Result Comparison

a,c

2.4    REFERENCES

2-1: WCAP-9401-P-A, "Verification Testing and Analyses of the 17 x 17 Optimized Fuel

Assembly," August 1981.

2-2: CENPD-178-P, Rev. 1-P, "Structural Analysis of Fuel Assemblies for Seismic and Loss of

Coolant Accident Loading,* August 1981.

2-3: APP-GW-GLR-153, Rev. 1, "AP1000 Core Reference Report," May 2015.

2-4: NRC NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for

Nuclear Power Plants: LWR Edition," (SRP) Section 4.2, "Fuel System Design," Revision 3;
     March 2007, Appendix A, "Evaluation of Fuel Assembly Structural Response to Externally

Applied Forces."
PWROG-16043-NP-A                                                                November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                   3-1
3        FUEL ASSEMBLY DYNAMIC CHARACTERISTICS AT EOL

CONDITIONS

This section describes the test protocol for determining the fuel assembly dynamic

characteristics at EOL conditions. The test protocol uses Westinghouse and CE PWR fuel

assemblies with simulated EOL grids for determining fuel assembly dynamic characteristics at

EOL conditions. A more detailed description is provided in the subsequent subsections.

The same test protocol has been previously applied to current Westinghouse and CE PWR fuel

designs for BOL conditions.

The test protocols are described in NRG-approved TRs WCAP-9401-P-A (Reference 3-1) and

CENPD-178-P, Rev. 1-P (Reference 3-2).

The main aspect of the testing described in this section that is different from what has been

previously approved by the NRG for current Westinghouse and CE PWR fuel designs is as

follows:
  [                                                                                         re

Even though this aspect has not been approved for current Westinghouse and CE PWR fuel

designs, it has been approved by the NRG for the AP1000 plant as described in TR APP-GW-
GLR-153, Rev. 1 (Reference 3-3).

For the testing performed in this program and described in this section, two fuel assembly

designs were used: the Westinghouse RFNRFA-2 and CE16NGF designs.

The results presented in this section are for the purpose of demonstrating the test protocol and

-~! tje~o~strati_n9J~_~_!=qL effe~s to det~rmir::i~_"!_e _!uel ~~mbly dynamic characteristics at

EOL conditions. The test protocol is applicable to all Westinghouse and CE PWR fuel designs.

3.1      EOL FUEL ASSEMBLY MECHANICAL TESTS

a,c

The mechanical tests obtained the fuel assembly (FA) static and dynamic characteristics, including FA modal frequencies and modal shapes, FA stiffness, FA structural damping, and fuel

assembly impact forces.

The FA lateral vibration tests were performed to obtain fuel assembly dominant modal

frequencies and modal shapes. The test fuel assembly is held with nominal hold-down force in

PWROG-16043-NP-A                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 3-2 the test stand with simulated lower and upper core plates. The typical mechanical test setup for

the lateral vibration tests is shown in Figure 3-1. A shaker is used to provide a sinusoidal

excitation force at approximately the middle of the test fuel assembly.

Two fuel assembly designs were tested. One test was performed for the RFA/RFA-2 fuel

assembly design for Westinghouse 12-foot cores. This assembly design features a 17x17 array

with a 0.374-inch diameter fuel rod. The RFA/RFA-2 design has six mid grids and three

intermediate flow mixing (IFM) grids.

The other fuel assembly design that was tested is the CE16NGF fuel for CE cores. This

assembly design features a 16x16 array with 0.374 inch diameter fuel rods. The CE 16NGF

design has nine mid grids and two IFM grids.

a,c

PWROG-16043-N P-A                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                      3-3
                                                   ---1 I

Elcc1ro

I

Mechanical

Shaker           I

I

__ ____ J

LoadCcll

Note: Place I LVDTs (II Total)
                          at Each Grid Elevation u Shown.

(a) 17RFA-2 Fuel Assembly                                 (b) CE16NGF Fuel Assembly

Figure 3-1 . Typical Fuel Assembly Lateral Vibration Test Setup

Table 3-1. Modal Frequencies of RFA/RFA-2 Fuel Assembly

(at Room Temperature and in Air)
                                                                                           a,c

PWROG-16043-NP-A                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                3-4 Table 3-2. Modal Frequencies of CE16NGF Fuel Assembly

(at Zero-gap and EOL Conditions)                           a,c

Note: Zero-gap results are from tests outside this PWROG program

3.2     REFERENCES

3-1 : WCAP-9401-P-A, "Verification Testing and Analyses of the 17 x 17 Optimized Fuel

Assembly,* August 1981.

3-2: CENPD-178-P, Rev. 1-P, "Structural Analysis of Fuel Assemblies for Seismic and Loss of

Coolant Accident Loading/ August 1981.

3-3: APP-GW-GLR-153, Rev. 1, "AP1000 Core Reference Report," May 2015.

PWROG-16043-NP-A                                                                November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                  4-1
4        FUEL ASSEMBLY FLOWING WATER DAMPING

This section describes the test protocol for determining the fuel assembly flowing water damping

ratio. The test protocol uses Westinghouse and CE PWR fuel assemblies with simulated EOL

grids for determining the fuel assembly flowing water damping ratio at EOL conditions. A more

detailed description is provided in the subsequent subsections.

Still water damping has been previously applied to current Westinghouse and CE PWR fuel

designs as described in NRG-approved TRs WCAP-9401-P-A (Reference 4-1) and CENPD-
178-P, Rev. 1-P (Reference 4-2)
The main aspects of the testing described in this section that are different from what has been

previously approved by the NRC for current Westinghouse and CE PWR fuel designs are:
                                                                                                       C

Even though there is no NRG-approved test protocol for determining the fuel assembly flowing

water damping ratio for current Westinghouse and CE PWR fuel designs, the test protocol in

this program is consistent with the test protocol approved by the NRC for the AP1000 plant as

described in Reference 5 of Section H of TR APP-GW-GLR-153, Rev. 1 (Reference 4-3).

Even though crediting flowing water damping for EOL conditions has not been approved for

current Westinghouse and CE PWR fuel designs, it has been approved by the NRC for the

AP1000 plant as described in TRAPP-GW-GLR-153, Rev. 1 (Reference 4-3).

C

---- -----             -*--
For the testing performed in this program and described in this section, two fuel assembly

designs were used: the Westinghouse RFA/RFA-2 and CE16NGF designs.

The results presented in this section are for the purpose of demonstrating the test protocol and

for determining the flowing water damping ratio at EOL conditions. The test protocol is

applicable to all Westinghouse and CE PWR fuel designs.                                             C

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WESTINGHOUSE NON-PROPRIETARY CLASS 3            4-2
4.1  DESCRIPTION OF FLOWING WATER DAMPING TESTS

a,c

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Figure 4-1. Test Loop Pressure Vessel and Pluck Mechanism

PWROG-16043-NP-A                                                      November 2019 Revision 2

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Figure 4-2. Flow Housing and Pressure Vessel (Top View)
4.2     BUNDLE FLOW RATE

The flow housi,ng used in the flowing water damping tests was larger than the standard flow

housing used for fuel assembly pressure drop tests, in order to accommodate the large fuel

assembly lateral vibration. A portion of the flow bypassed the assembly and flowed along the

sidewalls. Therefore, the flow through the fuel bundle could not be directly measured. The

average bundle flowrate was calculated based on the measured fuel assembly lift force and the

known bundle loss coefficients measured with the standard flow housing. The free body diagram

of the test fuel assembly subjected to external forces in the test loop is shown in Figure 4-3.

Fuel assembly

Figure 4-3. Fuel Assembly Free Body Diagram

PWROG-16043-NP-A                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                 4-5 In this diagram:
         Fs -top nozzle spring hold-down force

Fw - fuel assembly weight included buoyancy force

FL - the lift force due to flow impingement

R - reaction force on the lower core plate (measured by load cells)
Performing a force balance in axial direction:
                                                                                      (4-1)
Because Fw and Fs are constant for the same test temperature and without fuel assembly lift

off, the lifting force is given by the change in the load cell readings. The average bundle flowrate

is calculated based on the lift force and the known bundle loss coefficients.

a,c

Figure 4-4. RFA/RFA-2 Bundle Flow Rate Test Results

PWROG-16043-NP-A                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                       4-6 a,c

Figure 4-5. CE16NGF Bundle Flow Rate Test Results

4.3     FUEL ASSEMBLY FLOWING WATER DAMPING TEST CONDITIONS

a,c

4.4     FLOWING WATER DAMPING CALCULATION METHOD

Fuel assembly damping was obtained by pluck tests. Pluck testing is performed by displacing

the middle of the assembly at an initial lateral displacement and releasing the assembly to allow

a free vibration with no initial velocity. The pluck test, also known as the "decay method,D is

- - usea to ootain-the damping ratio-of a damped dynamie- system~ -The decay-rate, a measure of_
    damping, is expressed as the ratio of successive amplitudes. If x, and X,+1. represent the

amplitudes for the i111 and (i+1 ) 111 successive cycle, the logarithm of the ratio of two successive

cycles is called the logarithmic decrement (here called two successive amplitudes method, shown in Figure 4-6) and is denoted as (Reference 4-4):
                                                                                       (4-2)
    PWROG-16043-NP-A                                                                           November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                     4-7 Solving for the damping ratio, (, results in the following:
                                                                                    (4-3)
     The damping ratio obtained from the pluck test is based on the classic damping definition

(Reference 4-4).

X

I

Figure 4-6. Illustration of Two Successive Amplitude Method

Fuel assembly damping ratios in air can be reasonably obtained by the two successive

amplitudes method described in Equations (4-2) and (4-3) taken from Reference 4-4. However,_
- - -the-damping coefficients in-flowing water*are c::fifficulrttf obtaincyusinfEqu-atTcins (4~2fand

(4-3). As expected, fuel assembly damping in flowing water is much higher than in air.

Figure 4-7 shows typical assembly displacement histories. Since the damping is so high and

the assembly oscillation decays quickly, even the first vibration cycle is hard to recognize. To

obtain accurate damping coefficients for high damping cases, the initial displacement and first

response method based on classic vibration theory (References 4-4, 4-5, and 4-6) is therefore

used.

PWROG-16043-NP-A                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                   4-8 a,c

Figure 4-7. Fuel Assembly Decay Motion in Flowing Water

The fuel assembly oscillatory motion after a quick release from the initial displacement can be

expressed by a classic vibration equation ( c; < 1.0, Reference 4-4):
Where:
x(O), x(O) - Initial displacement and velocity, respectively

mn - Natural frequency

For a pluck test with x =    0, solving Equation (4-4) for the ratio x(t) I x(O) gives

x(t)/ x(O) = e-,,v,.1(     ~sin~l-,; 2 01,t+cos~l-,; 2 01.1]              (4-5)
                               O)n  1-(2 where x(O) is the initial pluck displacement and x(t) is the response as a function of time.

When the damping coefficient is higher than 0.4, the oscillatory motion decays very quickly, shown in Figure 4-7. It is difficult to recognize a full oscillatory cycle. However, the pluck initial

displacement and the first minimum amplitude can be measured with much better accuracy.

Setting x = x(min) (first response peak), the vibration duration is then ,c (1/2 cycle); therefore,
                                                                                  (4-6)
PWROG-16043-N P-A                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                4-9 and                                                                           (4-7)
Equation (4-5) with x(min) / x(O), becomes

x(min) I x(O)   = e-sm,.t (0 -1) or - x(O) I x(min) = esa>*'        (4-8)
SubstiMing Equation (4-7) into Equation (4-8), Equation (4-8) becomes

<5   = In   x(O)                                                    (4-9)
            IC      -x(min)
                                                                              (4-10)
Equation (4-10) is a special case of Equation (4-3), when the natural logarithm of the ratio of the

initial displacement to the first half-cycle amplitude.is used. The essential condition for using

Equations (4-9) and (4-10) is the initial velocity is equal to zero. Equations (4-9) and (4-10) are

used to obtain damping ratio from the pluck tests in this report.

4.5       FUEL ASSEMBLY FLOWING WATER DAMPING TEST RESULTS

a,c

PWROG-16043-NP-A                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                          4-10
                                                                                        a,c

Figure 4-8. RFA/RFA-2 Damping Ratios in Still and Flowing Water at 100&deg;F

a,c

Figure 4-9. RFA/RFA-2 Damping Ratios In Stlll and Flowing Water at 200&deg;F

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Figure 4-10. RFA/RFA-2 Damping Ratios in Still and Flowing Water at 300&deg;F

a,c

Figure 4-11. RFA/RFA-2 Damping Ratios in Still and Flowing Water at 380&deg;F

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WESTINGHOUSE NON-PROPRIETARY CLASS 3                   4-12
4.6  FLOWING WATER DAMPING RATIO

a,c

Figure 4-12. RFA/RFA-2 Damping vs Bundle Velocity

PWROG-16043-NP-A                                                  November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                  4-13 a,c

Figure 4-13. CE16NGF Damping vs Bundle Velocity

PWROG-16043-NP-A                                                 November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3               4-14 a,c

Figure 4-14. RFA/RFA-2 Damping vs Density

PWROG-16043-NP-A                                           November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                       4-15 a,c

Figure 4-15. RFA/RFA-2 Damping Ratio vs Bundle Velocity at 600&deg;F

a,c

Figure 4-16. CE16NGF Damping Ratio vs Bundle Velocity at 600&deg;F

PWROG-16043-NP-A                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                               4-16
4.7    BOUNDING DAMPING CURVE

To evaluate the effect of different PWR fuel designs on flowing water damping, the flowing water

damping data from the previous test for the Westinghouse 19x19 fuel assembly (Reference 4-3)
and RFA/RFA-2 are compared in Figure 4-17. The design features of the two test assemblies

are summarized in Table 4-1. -
                                                                                                   a,c

Figure 4-17. Damping Ratio vs Bundle Velocity Curve Comparison.

Table 4-1. Comparison of Test Assembly Geometric Features

a,c

PWROG-16043-NP-A                                                                  November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                              4-17 a,c

Fuel design specific flowing water damping coefficients at EOL conditions for Westinghouse and

CE PWR. fuel can be determined provided the test protocol described in this TR is used.

PWROG-16043-NP-A                                                                 November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                       4-18 a,c

Figure 4-18. Bounding Damping Ratio vs Bundle Velocity Curve

PWROG-16043-NP-A                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                               4-19
4.8     FLOWING WATER DAMPING CREDIT WITH REACTOR COOLANT PUMP

COASTDOWN DURING A SEISMIC EVENT

During a seismic event, reactor coolant pumps (RCPs) may trip, which would result in a pump

coastdown and core flow reduction. When the flow rate decreases during the pump coastdown, the fuel assembly flowing water damping is also reduced. A conservative fuel assembly flowing

water damping value was determined based on the flow rate during pump coastdown.

In the AP1000 EOL SSE (Safe Shutdown Earthquake) analysis, a conservative assumption was

made that the loss of offsite power and RCPs trip occurred simultaneously with a seismic event.

This assumption was approved by the NRC for analysis of the AP1000 plant (Reference 4-3).

The same assumption will be made for determining the appropriate flow rate for selecting the

damping ratio to be used in the seismic analysis.

The following discussion provides an example for how to determine the flowing water damping

ratio as a function of time during RCP coastdown. For a plant-specific seismic analysis, a plant

specific RCP coastdown curve will be used.

Typical pump coastdown curves for Westinghouse 3-loop/4-loop of 12-foot cores and CE

System 80 cores are very similar to that shown in Figure 4-19.

a,c

Figure 4-19. Typical RCS Pump Coastdown Curves

a,c

PWROG-16043-NP-A                                                                 November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                       4-20
                                                                                       a,c

Figure 4-20. Typical 3-Loop RCS Pump Coastdown Curve

a,c

Figure 4-21. Damping Ratio vs. Coastdown Time for a Typical Westinghouse 3-Loop Unit

PWROG-16043-NP-A                                                       November 2019 Revision 2

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4.9      FLOWING WATER DAMPING CREDIT FOR A LOCA EVENT

a.c

4.10     REFERENCES

4-1: WCAP-9401-P-A, "Verification Testing and Analyses of the 17 x 17 Optimized Fuel

Assembly," August 1981.

4-2: CENPD-178-P, Rev. 1-P, "Structural Analysis of Fuel Assemblies for Seismic and Loss of

Coolant Accident Loading,D August 1981.

4-3: APP-GW-GLR-153, Rev. 1, "AP1000 Core Reference Report," May 2015.

* 4-4: Theory of vibration with Applications, 3rd Edition, W. T. Thomson, Prentice Hall, 1988.

-4.. 5: MUAB--13020.,,NP, "Axial.E'lowDamping.Test of tbe FulLScale US-APWREuetAssembly,~
        August 2013, Non-Proprietary Version, Mitsubishi Heavy Industries, Ltd, August 2013.

4-6: R. Y. Lu and D. D. Seel, Westinghouse USA, "PWR Fuel Assembly Damping

Characteristics,D Proceedings of ICONE 14, 14th International Conference on Nuclear

Engineering, July 17-20, 2006, Miami, Florida, USA.

4-7: F. E. Stokes and R. A King, "PWR Fuel Assembly Dynamic Characteristics," International

Conference on Vibration in Nuclear Power Plants, Keswick, United Kingdom, May 9-12,
        1978 (BNES).

4-8: S. Pisapia, et al. "Modal Testing and Identification of a PWR Fuel Assembly," Transactions

of the 17th International Conference on Structural Mechanics in Reactor Technology

(SMiRT 17), Paper#C01-4, Prague, Czech Republic, August 17-22, 2003.

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WESTINGHOUSE NON-PROPRIETARY CLASS 3                               5-1
5        CONCLUSIONS

To address NRC Information Notice (IN) 2012-09 for the Westinghouse and CE PWR fuel

designs, the PWROG Analysis Committee and Westinghouse began work on this topical report.

This topical report is based on the NRC-approved approach used for the AP1000 Core

Reference Report and includes testing of Westinghouse and CE PWR fuel designs at simulated

EOL conditions.

The topical report addresses the following three key items with respect to evaluating the

structural integrity of fuel assemblies under faulted condition loads:
  [                                                                                         le

In this TR (PWROG-16043-P), the testing of two fuel designs is discussed. These were the

Westinghouse 17x17 Robust Fuel Assembly-2, herein referred to as "RFA/RFA-2,~ and the CE

CE 16NGF fuel designs.

The test protocols for determining grid impact strength, dynamic characteristics of fuel

assemblies, and flowing water damping described in this report characterize ,the EOL effects on

fuel assemblies and that the test protocols can be applied to all Westinghouse and CE PWR

fuel assembly designs.

This TR (PWROG-16043-P) does not supersede the NRG-approved TRs WCAP-9401-P-A and

CENPD-178-P, Rev. 1-P. Following NRC approval of this TR, it will be used as the basis for

determining fuel assembly characteristics and damping coefficients at EOL conditions for input

into plant-specific seismic/LOCA analyses that will be performed in accordance with the current

NRG-approved methods described in WCAP-9401-P-A and CENPD-178-P, Rev. 1-P.

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WESTINGHOUSE NON-PROPRIETARY CLASS 3            A-1 APPENDIX A

NRC Correspondence

PWROG-16043-NP-A                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                  A-2 OFFIElbliL USE ONLY

* PR6PRIETAR't INFORMATION

DRAFT SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION

2                        FOR TOPICAL REPORT PWROG-16043.P, REVISION 2.

3              "PWROG     PROGRAM TO ADDRESS           NRC  INFORMATION NOTICE 2012-09:
      4        'IRRADIATION EFFECTS ON FUEL ASSEMBL y SPACER GRJD CRUSH STRENGTH'
      5                         FQR WESTINGHOUSE AND CE PWR FUEL DESIGNS"
      6                   PRESSURIZED WATER REACTOR OWNERS GROUP (PWROG)
      7
      8   1.0      INTRODUCTION

9
    10    By letter dated February 1, 2017 (Reference 1), the Pressurized Water Reactor (PWR) 0.Vners

11    Group (PWROG or the appicant), submitted to the U.S. Nuclear Regulatory Commis5ion (NRC)
    12    staff for review licensing topical report (TR) P\IVROG-16043-P, Revision 2, "PWROG Program to

13    Address NRC Information Nobce 2012-09: 'Irradiation Effects on Fuel Assembly Spacer Grid

14    Crush Strength' for Wesmghouse and CE PWR Fuel Designs" (Reference 2, henceforth

15    referred to as the TR). Subsequent letters dated March 27, 2018, May 15, 2018, and May 15,
    16    2018 (References 3, 4, and 5, respectively), provided addltlonal Information that supplemented

17    the Information provided In Reference 2. The TR Is an extension of the previously approved

18    methodologies described In WCAP-9401-P-A (Reference 6) and CENP0-178(P), Rev. 1-P

19    (Reference 7), to assess the structural Integrity of fuel assembfl85 under faulted condition loads.

20    The methodologies descnbed in the TR can be used to develop fuel assembly characteristics

21    and damping coefficients for end-of-life (EOL) conditions that can then be used with the existing

22    testing and analysis methodologies for seismic and loss-of-coolant accident (LOCA) events.

23
    24    2.0      

==BACKGROUND==
25
    26    Seismic and LOCA events c.n result in external forces appled to the fuel asSQmblles

27    (e.g., shaking and/or vibratory forces). Therefore, applicants must evaluate the fuel assembly

28    structural response under these conditions to ensure that regulatory requirements are met with

29    respect to control r6d lnsertabDlty and core coolabUlty. In particular, the spacer grid

30    performance Is assessed to determine If plastic deformation Is expected to occur, and the fuel

31    assembly vibration behavior is quantified. Most PWR plants currently ublize the NRC approved

_32 __ testmg_and.analysis.methodologies_described.in References_6 and Z for Westinghouse.and CE

33    fuel designs, respectively.

34
    35    The NRC reviewed and approved References 6 and 7 based on the regulatory guidance

36    provided In Appendix A to Chapter 4.2 of the Standard Review Plan (SRP or Reference 8). One

37 assi.nption in the SRP Chaptlilr 4.2 Appendix A guidance at the time, which Is also in the

38    current revision from 2007, is that beglnnng of lire (BOL) Is the time at which the crushing load

39    for the spacer grids would be expected to be at a minimum. This assumption was based on the

40    fact that Irradiation tends to cause strengthening In metals and alloys in addition to

41    embrittlement. Other effects that arise due to use In a reactor may Include growth, cladding

42 creep, and corrosion. The increase in strength was expected to more than offset the other

43    affects associated with irradiated grids. Since applicants typically verify that the maximum load

44    experienced by the spacer grids during LOCA and seismic events will not exceed the crushing

45    load, use of BOL charactenstics was considered to be conservative.

Enclosure

OFFl6lAL USE ONLY         PR8PRIETARY INFORMit.TION

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-2-
     1  0perating experience that came to llght In the mid-2000s led the NRC staff to question the

2  assumption that the spacQr grid structural performance during LOCA and seismic events would

3  not degrade significantly as a result of rrradlation. The NRC subsequently issued Information

4  Notice ON) 2012-09, "Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength"
     5  (Reference 9). This IN fists several factors that can affect the structural strength of the spacer

6  grids, and singles out spacer grid spring relaxation as one that can have a significant effect on

7  the fuel assembly mechanical characteristics and the spacer grid strength. While no specific

8  action or response was required as a result of the IN, the NRC indicated that recipients would

9  be expected to review the Information for applicability and consider appropriate action to avoid

10  simfar problems.

11
    12  This TR Is the applicant's proposed approach to generically address the issue Identified in the

13  IN for licensees that use Westinghouse or CE fuel. In essence, this TR describes how to extend

14  the testing and analysis methodologtes in References 6 and 7 to determine an appropnate

15  crushing load for spacer grids at EOL. In addition, the TR proposes a methodology that can be

16  used to develop flowing water damping ratios that can then be credited in the LOCA and

17  seismic analyses in a simiar manner to the NRC approved stil water elem ping ratios (as

18  descnbed In References 6 and 7). This provides a means for ricensees to recover margin lost

19  due to the effect of spacer grid spring relaxation on the fuel assembly mechanlcal

20  characteristics.

21
    22  In summary, the existing NRC approved testing and analysis methodologies will continue to be

23  used, with all previously established Hmltatlons and conditions, but this TR extends the

24  applicability of the relevant aspects of these methodologies to the extent necessary to address

25  potential fuel assembly structural performance issues as a resul of irradiation.

26
    27  3.0      REGULATORY EVALUATION

28
    29  Title 10, "Energy," of the U.S. Code of Federal RegufatJon3 (10 CFR), Part 50, "Domestic

30  Licensing of Production and Utilization Facilities," Section 46, "Acceptance criteria for

31  emergency core cooling systems for llght-water nuclear power reactors," contains requirements

32  for the emergency core cooling system (ECCS) at commercial power plants. In particular,
    33  1O CFR 50.46(b)(4) requires that 1c]alculated changes in core geometry shall be such that the

34  core remains amenable to cooling." Any failure In the structural integrity of the fuel assemblies

35  wm typically change the core geometry, and the posslbilty needs to be evaluated.

36
    37  The regulatJon at 10 CFR Part 50, Appendix A, "General Design Cnterla for Nuclear Power

38  Plants: General Design Criterion (GDC) 10, "Reactor design: states that "[t]he reactor core ..

39  shall be designed with appropriate margin to assure that specified fuel design limits are not

40  exceeded during ... anticipated operational occurrences." Within the context of seismic events,
    41  this Is Implicitly addressed by ensuring adequate core coolability.

42
    43  The regulation at 10 CFR Part 50, Appendlx A, GDC 27, "Combined reactivity control systems

44  capability," states that "[t]he reactivity control systems shall be designed to ... reliably [controij

45  reactMty changes ...

* One of the primary reactivity control systems at current WEC and CE

46  PWR plants Is the rapid Insertion of control rods to add sufficient negative reactivity to shut

47  down the reactor. Rellable operation of this reactivity control system is condftlonal on the

48  capability to Insert the control rods. Vibrations or structural deformations may Impede the

49  control rod movement, and need to be evaluated.

50
                              OFFIGIAL USE ONLY          PROPrnETA-RY INFORMATION

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-3-
      1   The regulation at 1O CFR Part 50, Appendix A, GDC 35, "Emergency core cooling." restates the

2   requirement to maintain adequate emergency core cooOng capability, which can be affected by

3   the core geometry as discussed in 10 CFR 50.46(b)(4) (see above).

4
      5   The regulatlon at 10 CFR Part 50, Appendix A, GOC 2, "Design bases for protection against

6   natural phenomena," requires safety-related structures, systems, and components (SSCs),
      7   Including reactor fuel, to be designed to withstand natural phenomena (such as earthquakes)
      8   without a loss of capability to perform safety functions. This GDC also requires consideration of

9   "appropriatlil combinations of the effects of normal and accident conditions with the effects of the

10   natural phenomena." For example, a LOCA may be caused by a seismic event, so

11   consideration of the effects from a combination of these two events may be appropriate.

12
     13   Appendix S of 10 CFR Part 50 provides edcfrtlonal guidance for seismic events, and defines the

14   Safe Shutdown Earthquake (SSE), QPQrating Basis Earthquake (QBE), and safety requirements

15   for relevant SSCs. In general, stress, strain, and/or deformation limits should be defined for

16   each SSC to ensure its functional capabilities during each event Indicated by the regulatory

17   requirements (typically QBE, LOCA+SSE, and SSE-only, though other combinations may be

18   considered). These requirements are not explicitly addressed by the methodologies submitted

19   for NRC review, however, the overall methodology that PWRQG-16043 will supplement is

20   intended to demonstrate that these requirements are met Therefore, the NRC staff considered

21   the potential impact of PWROG-1 f3043. on how the 10 CFR Part 50 Appendix S requirements

22   would be met.

23
     24   The acceptance criteria for the structural response of fuel assemblies to exwmany applied

25   forces, in order to satisfy the above criteria, ere defined in Section 4.2, Appendix A of the SRP,
     26   otherwise known as NUREG-0800 (Reference 8). In general, the pnmary criteria are related to

27   ensuring that core coolability and control rod insertabllity are maintained.

28
     29   This TR is an application of an evaluatlon*model to perform licensing analyses for an accident

30   that the evaluation model has not previously been approved. As such, addrtlonal guidance for

31   the evaluation may be found In SRP Chapter 15.0.2, "Review of Transient and Accident

32   Analysis Methods" (Reference 10). This chapter includes provisions for the review of submittals

33   related to evaluation models.

34
     35   In summary, the NRC staff used the review guidance In SRP Crnlpter 15.0.2 along with the

36   applicable acceptance criteria In SRP Chapters 4.2 Appendix A In conducting Its review of the

_ 37 _TR. __ Since the_TRis_effectively a supplement tQ_e_l'(isting methQdQ.!Qgi~s._t@__scof?0 of _ti:le N~C

38   staff review was limited to the elements of the TR that represented a novel approach relative to

39   the existing methodologies, and to verify the app[Jcabllity of the existing methodologies when

40   conducting tests and evalUBtions as described in the TR.

41
     42   4.0     TECHNICAL EVALUATION

43
     44   The intent of the TR is to avoid extensive modification of previously approved analysis

45    methodologies documented in References 6 and 7 by focusing solely on the specific parameters

46  ,that would be Impacted by the EQL Issues k:lentlfled In IN 2012-09 (Reference 9). As such, the

47   TR narrowly focuses on three primary parameters:
     48
     49        1. The allowable grid mpact strength [

50
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     1      2. The fuel assembly modal frequencies [

2
     3
     4
     5
     6
     7                          ] and

8
     9      2. The fuel assembly flowing water damping ratio, [

10                                                        1
    11
    12  As a result, some of the areas from SRP Chapter 15.0.2 are not appllcable. In particular, the

13  analysis methodologies described In References 6 and 7 are not being modlfled, only the

14  empirical determination of key Input parameters. Therefore, the accident scenario dascription,
    15  the phenomena identification and ranking,_and code assessment from the previously approved

16  methodologies remain valid. The NRC staff review of the TR focused on two of the specific

17  areas descnbed In SRP Chapter 15.0.2, as described below:
    18
    19      1. Evaluation methodology - the proposed testing and data analysis methodologies,
    20           including any potential limitations to their applicability.

21
    22      2. Uncertainty analysis - the applicant's evaluation and propagation of uncertainties In the

23           analysis of test data to obtain recommended values for the key parameters.

24
    25  In addition, the NRC staff considered whether the applicant provided adequate quarrty

26  assurance (QA) and documentation support for the proposed methodologies. This aspect is not

27  explicltfy discussed in detail for this safety evaluation (SE) because the documentabon of the

28  proposed methodologies are captured by the documents reviewed by the NRC during an audit

29  dated October 17, 2017 (Reference 11) and that were found to have been appropriately

30  summarized or otherwise characterized in the TR. The testing was performed under the

31  auspices of the same QA program used to perform the testing for the previously approved

32  methodologies to determine the key parameters for BOL grids and still water damping, which is

33  acceptable. As such, the NRC staff acceptance of the adequacy of the applicant's evaluation

34  methodologies and uncertainty analyses lmpllcltly includes acceptance of the applicant

35  documentation associated with that area.

36
    37  4.1      EOL Grid Simulation

38
    39  All of the proposed methodologies in the TR are based on a specific characterization of the

40  impact of irradiation on the spacer grids. SRP Chapter 4.2 AppencflX A (Reference 8) cites

41  several possible irradiation-related effects relevant to spacer grids, and concludes that the

42  combined Impact would not be expected to lead to a more conservative result This logic rests

43  mainly on the fact that the signllcant increase in yield strength for the spacer grid material will

44  more than offset the relatively minor effects from the remaining effects. As described In IN

45  2012-09 (Reference 9), operating experience has shown that spacer grid spring relaxation can

46  have a significant adverse effect on spacer grid strength and fuel assembly mechanical

47  cha racterlstlcs. [

48
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       1
      2                              ] Other than grid spring relaxation, the basic assessment in SRP

3    Chapter 4.2 Appendix A that irradiation-related effects are bounded by the increase in the yield

4    strength of the spacer grid material continues to be appllcable. [

5
      6
      7
      8
      9
     10
     11
     12
     13
     14
     15                                                 As discussed in the previous paragraph, the NRC

16    staff found that the focus on the grid spring relaxation phenomenon as the key driver for the

17    non-conservative behavior Identified in spacer grids at EOL relative to BOL is appropriate.

18    However, the material and geometry impacts of the thermal relaxation process must be

19    reasonably similar to the Irradiation-induced impacts that are being simulated.

20
     21
     22
    .23
     24
     25
     26
     27                                                  ] Therefore, the NRC staff requested additional

28    information from the applicant regarding the thermal relaxation procedure used to produce the

29    simulated EOL grids. [

30
     31
     32
     33
     34     ] The applcant's response also confirmed that the material structural characteristics of the

35    simulated EOL grids are the same, or slightly conservative, relative to the BOL grids.

36
     37__ .[

38
     39
     40
     41                                                           ] There are some situations where a spacer

42    grid Is exposed to a strongly norHJnlform neutron flux, such as fuel assembly loading locations

43    at or near the core periphery The NRC staff asked the applicant to address the potential

44    impact on the grid fa~ure mechanism due to non-random gradients in gap size that may be

45    correlated wlh steep neutron flux gradients. [

46
     47
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     1
     2
     3
     4  Filally, Chapter 2.1 of the TR described how the target average gap size was determined for a

5  given spacer grid. [

6
     7
     8
     9
    10
    11                                                                                          ]
    12  Inadequate information was given In the TR to define the area of appllcabillty for extrapolation of

13  a given set of PIE data to the general population of EOL grid spacers of the same design, so the

14  NRC staff requested that the applicant characterize how Pl E data sets are generally defined in

15  order to achieve their intended purpose.

16
    17  The applicant responded in Reference 4 with an explanation of the statistical methodology

18  underlying their determination of a target gap size for the simulated EOL grids. [

19
    20
    21
    22
    23
    24
    25
    ~                                                                                   ]th~isa

27  reasonably conservative approach to ensure that the average gap sizes for the simulated EOL

28  grids wil bound the average gap sizes for irracfrated grids.

29
    30
    ~                                                                                   )~
    32  NRC staff agrees, however, the applicant did not describe how the rod bumups associated with

33  the PIE measurements would be used to define the area of applicabtlity for fuel assemblies

34  qualified under.this methodology. In a separate RAI response (RAl-2, documented ln

35  Reference 4), the app~cant provided Information that shows that the variation in gap sizes for

36  varying bumups near EOL can be expected to be minor relative to the inherent randomness in

37  gap sizes within a grid. In addition, the NRC staff noted that the methodology descri>ed n

38  Reference 7 for testing of CE design fuel assemblies includes modeling for both BOL and EOL

39  grids. [

40
    41
    42
    43                                    ] Consistent wrth this assessment, the results from the testing

44  discussed in Sections 4.2 and 4.3 of this SE show [

45
    46                             ] Therefore. any vartatlons In bumup for the fuel assemblies used to

47  obtain PIE measurements relative to the overall population of fuel assembfies being quahfied

48  under this methodology would not result In a significant difference In average gap size, certainly,
    49  much less than the inherent conservatism In the margin between the average measured gap

50  sizes and the target gap size for the simulated EOL grids.

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     1
     2
     3
     4
     5
     6
     7
     8                                    ] As a result, the NRC staff found the proposed approach to

9  generate simulated EOL grids for use in testing in lieu of iTadiated grids to be acceptable.

10
    11  4.2      Spacer Grid Impact Strength

12
    13  Chapters 22 and 2.3 of the subject TR discuss the application of the approved testing and data

14  analysis methodologies from References 6 and 7 to determine the anowable grid impact

15  strength for the simulated EOL grids. In an respects, the testing and data analysis applications

16  were consistent with References 6 and 7, [

17
    18
    19
    20                            ]. The NRC staff understanding of the approval request from the

21  appllcant Is that this change in criterion was adopted merely for demonstration purposes, not

22  being submitted as an update to the Reference 6 methodology. In response to a RAI from the

23  NRC staff (Reference 3), the applicant confrnled that this was the case. Therefore, this

24  application was judged to be acceptable solely for the purpose of providing a more consistent

25  basis for comparing the change In P(crlt) for Westinghouse and CE fuel designs.

26
    27  The simulated EOL grids contain [

28
    29         ] The NRC staff vertfied by inspection of the applicant's test documentation that the failure

30  mechanism for the simulated EOL grids was the same as that for the BOL grids. Therefore, [

31
    32
    33                                 ] As discussed in Section 42 of this SE, [

34
    35
    36
    37 ___ I ___ _
    38
    39  The NRC staff verified that the previously approved testing and data analysis methodologies

40  from References 6 and 7 were appropriately applied to the simulated EOL grids. In addition, the

41  NRC staff found reasonable assurance exists that the aforementioned methodologies remain

42  appllcablri1 to the geometry of the simulated EOL grids. Therefore, the NRC staff found the

43  methodologies to determine P(crit) to be acceptable for use in analysis of the simulated EOL

44  grids.

45
    46  4.3      Fuel Assembly Mechanical Characteristics

47
    48  Chapter 3 of the TR discusses the appffcatlon of the approved testing and data analysis

49  methodologies from References 6 and 7 to determine the allowable gnd impact strength for the

50  simulated EOL grids. The TR states that "{t]he same test protocol has been previously applied

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     1  to current Westinghouse and CE PWR fuel designs for BOL conditions," and that 1t]he test

2  protocols are described In NRC-approvad TRs .. ." with a citation to R'1ferences 6 and 7.

3  Therefore, the TR clearly characterizes the testing procedure for the simulated EOL grids to be

4  Identical to the preVK>usly approved testing procedure described in References 6 and 7, with the

5  exception that the grids are simulated EOL grids as discussed In Section 4.1 of this SE.

6
     7  The testing methodologies described In References 6 and 7 are primanly tests conducted on the

8  structural members of the fual assembly and the spacer grids, with no tests directly impacting

9  the fuel rods. At SOL, the grid spnngs exert a frictional force on the fuel rods, so the spacer

10  grids and fuel rods are mechanically coupled to some extent. During the fuel assembly vibration

11  tests, the fuel rods contribute to the fuel assembly mechanical perfonnance by virtue of this

12  mechanical coupling. [

13
    14
    15
    18
    17
    18
    19
    20
    21
    22
    23  4.4      Procedure to Determine Flowing Water Damping Ratios

24
    25  Chapter 4 of the TR descrbes a methodology to determine fuel assembly flowing water

26  damping ratios and apply them In lieu of previously approved stm water damping ratios to

27  characterize the fuel assembly mechanical behavior during seismic and LOCA events. Since

28  the damping ratio due to flowing water is expected to be higher than that for still water, this

29  approach could help recapture margin lost due to the impact of grid spacer relaxation on the fuel

30  assembly stiffness. [

31
    32
    33
    34
    35  Chapters 4.1 through 4.3 describe the test apparatus and data conection performed to support

36  an empirical determination of the flowing water damping ratios. [

37
    38
    39
    40
    41
    42
    43                                              ] However, the hydraulic characteristics for the fuel

44  assembly are well characterized based on prior testing. [

45
    46
    47
    48
    49                                                                                       ] Since the

50  loss coefficients for the fuel assembly designs have been approved by the NRC for use in other

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     1    analyses and would not be expected to vary significantly as a result of the use of simulated EOL

2    grids, this approach for determining flow velocitl8s through the fuel assembly Is acceptable.

3
     4    The existing analysis methodologies, most notably the Reference 7 methodology for CE fuel, (
     5
     6
     7
     8
     9
    10
    11                     ] Testing performed on similar fuel assembly designs using a range of different

12    approaches, as documented In References 14 and 15, yield consistent resulb. [

13
    14
    15                                                                  ] This shows that the proposed

16    methodology ylekls results consistent with currently approved methodologies.

17
    18    The flowing water damping ratio correlation was developed based [

19
    20
    21
    22
    23
    24                                                                                          ] Therefore,
    25     there wrn be no inconsistency In the application of damping ratios for fuel assembles at different

26     burnup concfrtions.

27
    28     Based on the data collected from the  tests, a damping ratio was determined for each test based

29    on c ~ I vibration theory. [

30
    31          ] Chapter 4.5 of the TR presents results from the tests. One of the most important

32    conclusions that can be observed directly from the test results is that [

33
    34
    35                                                                                 ] Since the use of

36     lower damping ratios in developing the correlation Is conservative, this was an acceptable

37_ __ choice to_make.

38
    39     Chapter 4.6 of the TR cfrscusses the data analysis approach used to determine bounding

40     correlations for each fuel assembly design. This approach can be summarized thus: [

41
    42
    43
    44
    45               ] The overall approach appears to capture the relevant dependencies, however, there

46     Is no propagation of the uncertainties due to scatter in data through the steps noted above. [

47
    48
    49
    50
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     1
     2
     3
     4
     5 The applicant responded in Reference 5 with information incficatlng that the fitting approach

6 used to determine the bounding curve was fundamentally a best estimate approach to derive

7 the 600 &deg;F curve based on the selected data set (
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30 Fr,ally, Chapter 4.7 proposes use of a flowing water damping ratio correlation based on the

31 [       ] fuel assembly design as a generically bounding correlation that may be used wrth

32 any fuel assembly design without further justification. The methodology discussed above may

33 be used to develop fuel assembly design specific correlations, but the [                ] correlation is

34 proposed for use as a bounding curve for all Westinghouse and CE fuel designs. The

35 justification provided is that the [    ) fuel assembly design proposed for the [            ] reference

36 plant contains a number of significant design differences, but test results show that the flowing

37 water damping ratio is very slmilar to the [             ] fuel. The CE fuel design tested had

38 [

39
    40                                                                                       ) This behavior is

41 bounded by the [            ) correlation, so this ls acceptable. However, [

42
    43                                                      ] Therefore, the similarity in results is not

44 surprising.

45
    46 In order to establish that the proposed correlation can be used as a generic bounding curve, its

47 appllcabillty must be Rmlted to spacer grids with very slmUar geometry characteristics. This is

48 accomplished via a condition to the TR. Information submitted In References 14 and 15 provide

49 lnforrnabon for other PVVR fuel assembly designs that suggests that, In fact, the [

50
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     1  As long as tha geometry characteristics of the spacer grids associated with a different fuel

2  assembly do not differ significantly from the [             ] spacer grid, the NRC staff finds that

3  reasonable assurance exists that other fuel assembly designs will have flowing water damping

4  ratios near or above the proposed bounding curve. The proposed application includes use of a

5  minimum value for the analysis duration rather than a more realistic average value, which

6  incorporates some additional conservatism that offsets the potential for slightly lower flowing

7  water damping ratios for some fuel assembly designs relative to the proposed bounding curve.

8
     9  Based on the information provided in the TR, as supplamentad by responses to requests for

10  additional information from the NRC staff, the testing protocol and data analysis methodologies

11  described to determine appropriate flowing water damping ratios were determined to be

12  appropriate for their intended purpose. In addition, [

13
    14
    15                                                ] This latter condition was captured in Section 5.0.

16
    17  4.5      Analytical Application of the Flowing Water Damping Ratios

18
    19  Chapters 4.8 and 4.9 of the TR describe when and how the flowing water damping ratios can be

20  utilized in seismic and LOCA analyses, respectively. The primary parameter used to establish

21  the appropriate value for the flowing water damping ratio is the fluid velocity through the fuel

22  assembly. For a given plant, this parameter is directly correlated with the core flow. Therefore,
    23  the discussion in the TR primarily focuses on the characterization of a bounding core flow for

24  any given time of interest during the event being analyzed. Once en appropriate value is

25  determined, then plant-specific information can be used to establish an appropriate flow velocity

26  to use with the flowing water damping ratio correlation. [

27
    28                       ] In general, since lower flow velocities result in lower flowing water damping

29  ratios, any factor that may lead to a reduction In the core flow rate wm provide more

30  conservative results. For a given analysis, [

31
    32
    33
    34
    35  For the seismic analysis, two key assumptions are made to minimize the total core flow. Fll'st, [

36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47  Secondly, [

48
    49
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     1
     2
     3                                                                                                ] At

4   this time, the flowing water damping ratio will be at a minimum, and lower than the average

5   flowing water damping ratio for the interval. Since these assumptions both act to minimize the

6   flowing water damping ratio, they are conservative.        *
     7
     8   For the LOCA analysis, the core flow rates are to be obtarned directly from the LOCA analyses,
     9   as long as axial flow Is maintained. [

10
    11
    12                           As a result, the NRC staff finds that the LOCA analysis conditions are an

13   acceptable source for a bounding core flow rate for the purpose of determining flowing water

14   damping ratios.

15
    16   A second Imitation of the flowing water damping ratios Is that the data used as a basis for the

17   correlation were based on single phase liquid flow through a fuel assembly. The conditions

18   under which the flowing water damping ratios are expected to be credited-seismic events and

19   the first -1 second of a LOCA event-are not expected to Involve two phase flow In the core.

20   However, the TR does not explicify nmlt the use of flowing water damping ratios to single phase

21   flow conditions, so a Imitation was included In Section 5.0 to ensure that, If this methodology is

22   applied to conditions that deviate from expectations, the correlation will not be used outside the

23   bounds of its appllcabBlty.

24
    25   The NRC approval of Reference 13 included review of information demonstrating that the

26   Westinghouse models were capable of capturing the dynamic behavior of fuel assemblies for

27   pluck response inside a flow loop, for the vibration range of interest Since the flowing water

28   damping ratios are very similar for the RFA/RFA-2 curves being proposed for use as a bounding

29   curve for all fuel assembly designs and the Reference 13 fuel design contained a similar spacer

30   grid design, this finding ls applicable to the subject LTR as well. However, without further

31   vandatlon, the dynamic models cannot be assumed to maintain reasonable accuracy for

32   damping ratios that go significantly beyond the current area of appricabllity. Therefore, any use

33  -of damping ratios significantly higher than the proposed bounding curve must be supported by

34   vandatlon against test data that demonstrates that the analytical models remain vaid for the

35   higher damping regime. A nmltation was Included In Section 5.0 to ensure that this potential

36   limitation of the analytical models ls addressed, If necessary.

37
    38   The guidance provided in the TR to credit flowing water damping in seismic and LOCA analysis

39   was reviewed by the NRG staff and determined to produce acceptably conservative results for

40   the expected analysis conditions. Therefore, the NRC staff finds the proposed appHcatlon of

41   flowing water damping credit for evaluation of fuel assembly mechanical behavior du-Ing

42   seismic and LOCA events to be acceptable.

43
    44   4.6      Known Legacy Issues

45
    46   There are a number of potential Issues with the previously approved methodologies described In

47   References 6 and 7. They include:
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     1        *    [

2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24    These Issues may have been addressed for legacy fuel assembly designs based on expected

25    fuel assembly grid behavior and testing. However, the current approved methodologies do not

26 provide a generic approach to do so, Therefore, the assumptions Inherent in the technical

27    justification for these issues need to be evaluated on a case-by-case basis for new fuel

28 assembly designs, which may depend on consideration of all attnbutes of the proposed

29 revisions to the plant ncensing basis The new proposed approach to credit flowing water

30    damping ratios represents a more realistic approach. As such, there Is a reduction In

31 , conservatism for this approach relative to the previously approved approach to credit still water

32 damping. Therefore, the overao justification for the above issues must be re-evaluated to

33    ensure that the overall analysis remains conservative.

34
    35    As cllscussed above, the NRC staff Identified some technlcal Issues that are not expllcltly

36    addressed by the currently approved methodology. They may have been addressed for current

37- -tue1 assembly deslgns;-however.-the use-of a more reallstlc flowing water dampfng ratio-*
    38    represents a reduction In conservabsm for the damping ratio approach relative to the previously

39    approved approach. Therefore, the NRC staff is imposing nmitations and conditions to ensure

40    that the overaD conservatism of the analysis is acceptable             *
    41
    42    s.o      LIMITATIONS AND CQNPJTIQNS

43
    44    Some lfmitatlons and conditions are necessary to ensure that the methodology dlscUSSQd in the

45    TR ls frrnited to the appications for which it is vafid. These limitations and concfrtions are listed

46    below.

47
    48         1. [

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     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22  6.0      CONCLUSIONS

23
    24  In the TR, the applicant presented new models and methods to extend the applicability of

25  existing methodologies to evaluate spacer gnd and fuel assembly mechanical behavior dunng

26  seismic and LOCA events. The following conclusions are provided here in summary as they

27  apply to licensees who may want to adopt the methodologies described in the TR with existing

28  methodologies in References 6 and 7 to address the effect of irradiation on the mechanical

29  properties of fuel assemblies.

30
    31  Since the TR is not proposing any change to the previously approved testing and analysis

32  methodologies for seismic and LOCA events, the NRC staff performed a graded review of the

33  methodologies that took into consideration the fact that most aspects of the testing and analysis

34  have already been addressed as part of prior NRC reviews. The applicant requested approval

35  for three distinct enhancements to their existing methods: (1) use of simulated EOL spacer

36  grids to assess spacer grid crush strength at EOL: (2) use of simulated EOL spacer grids to

37  assess fuel assembly mechanical charactenstlcs, such as stiffness, at EOL; and (3) use of a

38  new methodology to develop flowing water damping ratios that can be used in lieu of the

39  currently approved still water damping ratios

40
    41  The NRC staff examined the proposed approach to produce simulated EOL spacer grids and

42  use them with previously approved methodologles, and determined that the simulated EOL

43  spacer grids would adequately capture the non-conservative impacts due to irradiation. The

44  staff also determined that the [

45
    46
    47                                             ] The NRC staffs findings were ba~ primarily on

48  the specfflc material type (zirconium alloy) and general grid design covered by the Information

49  presented in the TR, [

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     1
     2  The use of flowing water damping ratios is not an entirely new approach to develop more

3   realistic parameters that help mitigate the impact of vibratory loads, because it is similar to a

4   methodology submitted as part of the NRC approwl of the AP1000 reference plant design

5   (Reference 14). However, this Is the first time that it Is being applied more generically to

6  Westinghouse and CE fuel. In particular, the applicant is proposing the use of a bounding curve

7  that Is applicable to all spacer grids used in Westinghouse and CE fuel, along with a general

8   methodology that can b1.1 used to generate fuel design s&#xb5;Qeiflc curves. The staff reviewed the

9   information submitt1.1d in the TR along with responses to requests for adcitional information, and

10  determined that the methodology was appropriate for both purposes. Additionally, the guidance

11   provided for utilization of flowing water damping ratios in seismic and LOCA analyses was found

12  to be appropriate for their intended use, with the limitations that: (1) the flowing water damping

13   ratios are only valld for single phase liquid flow, and (2) the dynamic models used to predict the

14  fuel assembly response under vibratory and damping loads must be verified to remain

15   reasonably accurate for higher damping regimes by validation against test data, prior to use for

16  safety analysis purposes.

17
    18  The NRC staff also acknowledged some legacy Issues with lack of clear guidance to address

19   certain aspects of current NRC regulations. Since approval of use of specific fuel assembly

20   designs at specifre plants may have depended on consideration of fuel design specific

21   characteristics that would disposition or offset the legacy Issues, the NRC staff finds that any

22   reduction in analytical conserwtism should not be made Without addressing these legacy

23   issues, as discussed in Section 4.6. The use of flowing water damping ratios represents one

24   such reduction in anelytlcal conservatism, therefore, a condition for use of the new damping

25   ratios is that the legacy issues need to be addressed.

26
    27   In summary, the NRC staff finds that the information provided In the TR and responses to NRC

28   staff RAls adequately demonstrates that the proposed methodologies to address EOL effects on

29   spacer grids and to recover margin through credit for flowing water damping are acceptable for

30   use with existing methodologies that the NRC has previously found to be acceptable for

31  analysis of fuel assembly structural behavior during seismic and LOCA events. The NRC staff

32   approwl of these methodology extends to all Westinghouse and CE fuel designs, contingent on

33   adherence to the Dmitatlons and conditions set forth in Section 5.0.

34
    35   7.o      REFERENCE&sect;
    36
    37- -1. PWROGJetter.OO~fZ-12, JaclcStrlngfellow, Chief_Operatmg_~r an<l Qhalrmar:i, __
    38       P\NROG, to USNRC document control desk, re: "Submittal of PV\iROG-16043-P, Revision

1
    39       2, 'PWROG Program to Address NRC lrtormation Notice 2012-09: 'Irradiation Effects on

40       Fuel Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
    41       PA-ASC-1169R2," February 1, 2017 (ADAMS Accession No. ML 170398050)
    42
    43   2. PWROG-16043-P, Revtsion 2, "PWROG Program to Address NRC Information

44       Notice 2012-09: 'Irradiation Effects on Fuel Assembly Spacer Gnd Crush Strength' for

45       Westinghouse and CE PWR Fuel Designs," January 2017 (ADAMS Package Accession

46       No. ML170398061)
    47
    48   3. PWROG letter OG-18-62, Jack Stringfellow, Chief Operating Officer and Chairman,
    49        PWR0G, to USN RC document control desk, re: "Transmittal of the Response to Request

OFFIGIAL USE ONLY          PROPRIETARY INFORMATION

PWROG-16043-NP-A                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           A-17 OFFICIAL USE ONLY       PROPRIETARY INF6RMATION

-16-
     1       for Addtlonal lnformabon, RAJs 4 and 5 Associated with PWROG-16043, Revision 2,
     2       "PWROG Program to Address NRC Information Notice 2012-09* 'Irradiation Effects on Fuel

3       Assembly Spacer Gnd Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
     4       PA-ASC-1169," March 27, 2018 (ADAMS AccesslOn No. ML 18100A053)
     5
     6  4. PWROG letter OG-18-104, Jack Stringfellow, Chief Operabng Officer and Chairman,
     7       PWROG, to USNRC document control desk, re "Transmittal of the Response to Request

8       for Additional lnformabon, RAls 1, 2, and 3 Associated with PWROG-16043, Revision 2,
     9       "PWROG Program to Address NRC Information Notice 2012-09: 'Irradiation Effects on Fuel

10       Assembly Spacer Grid Crush Strength' for Westinghouse and CE PWR Fuel Designs,'
    11       PA-ASC-1169," May 15, 2018 (ADAMS Access10n No. ML 18143B462)
    12
    13  5    PWROG letter OG-18-105, Jack Stnngfellow, Chief Operating Officer and Chairman,
    14       PVVROG, to USNRC document control desk, re. "Transmittal of the Response to Request

15       for Addmonal Information, RAI 6 Associated wrt:h PWROG-16043, Revls10n 2, "PWROG

16       Program to Address NRC Information Notlce 2012-09: 'lrradlabon Effects on Fuel Assembly

17       Spacer Gnd Crush Strength' for Westinghouse and CE PWR Fuel Designs,' PA-ASC-1169,"
    18       May 15, 2018 (ADAMS Accession No. ML 18144A760)
    19
    20  6    WCAP-9401-P-A, Revision 0, "Verif1cabon Testing and Analysis of the 17x17 Optimized Fuel

21       Assembly," September 1981 (ADAMS Accession No. ML090280466 (Non-Publicly

22       Avaftable))
    23
    24  7. CENPD-178(P), Revision 1-P, "Structural Analysts of Fuel Assemblies for Se1sm1c & LOCA

25       Loading," August 1981 (ADAMS Access10n No. ML 14122A086 (Non-Publicly Available))
    26
    27  8. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear

28       Power Plants* LWR Edition," Chapter 4.2, Revision 3, "Fuel System Design," March 2007
    29       (ADAMS Accession No ML070740002)
    30
    31  9. NRC Information Notice 2012-09, "Irradiation Effects on Fuel Assembly Spacer Gnd Crush

32       Strength," dated June 28, 2012 (ADAMS Accession No ML 113470490)
    33
    34   10. NUREG-0800, "Standard Review Plan for the Revtew of Safety Analysis Reports for Nuclear

35       Power Plants: LWR Edition," Chapter 15.02, Revision 0, "Review of Transient and Accident

36       Analysts Methods," March 2007 (ADAMS Accession No ML070820123)
    37
    38  11. NRC letter from Brian Benney, Senior ProJ9Ct Manager, Licensing Processes Branch,
    39       Division of Policy and Rulemaking, USNRC, to Jack Stnngfellow, Chief Operabng Officer

40       and Chairman, PWROG, re "Summary Report for the October 17, 2017, Audit In Support of

41       the Review of PWROG-16043-P, Revision 2, "PWROG Program to Address NRC

42       Information Notice 2012-09. 'Irradiation Effects on Fuel Assembly Spacer Gnd Crush

43       Strength' for Westinghouse and CE PWR Fuel Designs," January 8, 2018 (ADAMS

44       Accession No. ML 17326A003)
    45
    46  12 Framatome ANP, Inc. letter NRC:03:051, James F. Maliay, Director, Regulatory Affairs,
    47       Framatome ANP, Inc., to USNRC documerrt control desk, re. "Closure of Interim

OFFIGIAL USE ONLY       PROPRIETARY INFORMATION

PWROG-16043-NP-A                                                                                  November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                              A-18 OFFIGIAL USE ONLY        PROPRIETARY INFORMATION

-17-
     1      Report 02-002, 'Spacer Grid Crush Strength - Effects of lrrad1at1on.'" August 8, 2003
     2      (ADAMS Accession No ML032240425)
     3
     4  13 WCAP-17524-P/NP-A, Revision 1, "AP1CXXl Core Reference Report." May 2015 (ADAMS

5      Accession No. ML15180A175)
     6
     7  14. Westmghouse letter LTR-NRC-13-26, James A. Greshman, Manager, Regulatory

8      Compliance, Westinghouse Electric Company, to USNRC document control desk,
     9      re: "Supplemental Information on End-of-Life Selsmlc/LOCA calculations for the AP1000
    10      Pressurized Water Reactor (Propnetary/Non-Proprletary)," April 30, 2013 (ADAMS

11      Accession No. ML 13128A017)
    12
    13  15. Framatome Inc. report ANP-10337P-A, Revision 0, "PWR Fuel Assembly Structural

14      Response to Externally Applied Dynamic Excitations," April 2018 (ADAMS Package

15      Accession No ML18144A816)
    16
    17  Principal Contnbutor: Scott Krepel, NRR/DSS/SNPB

18
    19  Date: August 22, 2018 OFFICIAL USE ONLY       PROPFUETARY INFORMATION

PWROG-16043-NP-A                                                                                  November 2019 Revision 2

VVESTINGHOUSE NON-PROPRIETARY CLASS 3                                          A-19 Comment Text Locabon        PWROG Comment         NRC Response

Number  PaQe       Line     (paraphrased)
         1       Multiple   Multiple Some phrases (e g.,   The staff agrees that the

page 1, Imes 17-18)   distinction is useful to support

are inconsistent with consistency and clarity In the

how the purpose of    discussion, and has generally

the TR ls             made changes to the DSE

characterized In      consistent wrth what PVVROG

Section 1 .3.         recommended.

Throughout the draft

safety evaluation     Note this comment and

(DSE), the term       response encompasses all

"methodology"         proposed changes that are not

should be replaced    expllcltly identified m the

wlh alternative       following comments

terms to clarify the

relationship between

the analytical

methods and the test

protocol or

approaches used to

develop parameters

for use 1n the

analytical methods.

2       2           48      C larlf1cation that   The staff agrees, and the

statement applies to  proposed changes were

both LOCA and         Incorporated as-is.

seismic events.

3       3          21-30    The paragraph         The staff does not agree The

associated with 10    regulations define the

CFR 50, Appendix S    requirements, while the criteria

should be deleted,    provided in the SRP and other

s Ince the specific   guidance documents are not

cntena are            bmdmg. As such, the

discussed In the      regulations form the regulatory

following paragraph.  basis, while the SRP provides

additional guidance for

acceptable approaches to

demonstrate that the regulatory

requirements are met. The staff

did revise the paragraph shghtly

to refer to "cnteria" rather than

"limits" to be consistent wrth the

discussion elsewhere In the

DSE.

4       3           32-37   Editorial changes     The staff agrees, and the

proposed for          proposed changes were

readability.          Incorporated as-1s.

5       3           40-49   These paragraphs      The staff agrees, consistent wrth

4           1-2     are not consistent    the resoonse to comment #1 PWROG-16043-NP-A                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                    A-20
         Comment Text Location                 PWROG Comment          NRC Response

Number  Page                Line      (paraphrased)
                                               with the intent of the (above) 1ne paragraphs were

TR to provide an       deleted, however, some

alternate approach     additional text was added to

for determining        clarify that the NRC staff did

Input, as opposed to   consider the applicability of the

a change In the        analysis methodologies

analysis method.       described In References 6 and

7 when the parameters of

interest are developed with the

new approaches. When pnor

review and approval of

analytical methods are based, In

part, on recommendations for

development of input

parameters, this aspect cannot

be completely divorced from the

analvtlcal methods.

6       6&                  22 &      Replace use of the     The staff agrees, and the

elsewhere           elsewhere word "Chapter" with    proposed changes were

"Section."*            Incorporated as-is.

7       7                   34-46     Proposed rewnte for    The staff agrees, and the

clarity                proposed changes were mostly

Incorporated as-ls. However, the characterization of the

plastic deformation

demonstration for

Westinghouse grids as an

"exception" was left in, since

this 1s an Important

clarificatlon--thls is not

consistent with References 6 and 7, however, PWROG is not

requesting approval for use of

this aooroach

8       9                   44        Update text to crte    The staff agrees that this edrt

--  _ ___.__ - -   ----    specific references-   proVJdes addrtional clarity, but

for approved           addltlonal detail was Included

methods.               for completeness.

9       10                  28        Proposed               The staff disagrees. The

replacement of text.   proposed rewrite would change

the meaning of the sentence

and be Inconsistent with the

discussion in the following two

oaragraphs.

10      12                  30        Proposed rewnte to     The staff agrees, and the

be consistent with     proposed changes were

the TR.                incoroorated as-is.

PWROG-16043-NP-A                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                          A-21 Comment Text Location     Pv't,ROG Comment       NRC Response

Number  Paae        Line  (paraphrased)
         11      13          4-15   1ne Issue with        The staff disagrees. While the

14          42-47 validity of the models analytical methods are not

used to predict the    being updated, the proposed

dynamic behavior of    approach may produce damping

fuel assemblies        ratios that are much higher than

pertain to the         the range considered when the

analytical methods,    analytical methods were

which are not being    reviewed Consequently, updated or reviewed    questions exist about the

by the NRC.            applicability of the analytical

Therefore, It Is       methods for much higher

inappropriate to       damping ratios. The staff

address this Issue as  revised the limitation and

part of the revtew of  condition to provide more

PWROG-16043.           latitude In what kmd of

information a licensee must

provide In order to credit

significantly higher damping

ratios

12      13          23-49 The issues             The staff agrees that the legacy

14          2-18  discussed regarding    issues are not part of the review

36-40 legacy Issues pertain  scope for this TR, but disagrees

to the analytical      that they cannot be considered

methods, which are     as part of the basis for approval

not being updated or   of this TR. The legacy issues

reviewed by the        were not considered as part of

NRC. Therefore, it 1s  the review of PWROG-16043.

Inappropriate to       However, PWROG-16043 address this Issue as  requests approval for an

part of the revtew of  approach that removes

PWROG-16043.           conservatism from analyses

performed using the analytical

method. This conservatism, among other factors, was used

to risk inform the staffs daCJsion

not to pursue resolution of the

legacy issues As a result, If

licensees wish to remove thJS

conservatism, they need to

provide information to resolve

the Issues. This Information has

already been provided and

reviewed In some cases (e.g ,
                                                          Reference 13). The staff

rewrote Section 4.6 and the

limitation and condition to

provide better clarity on the

Issues that need to be

PWROG-16043-NP-A                                                                          November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                       A-22 Comment Text Locabon     PVVROG Comment        NRC Response

Number  Paoe        Lne  (paraphrased)
                                                        addressed and now they can be

addressed

13      15         17-22 Proposed rewrite to   The staff agrees, and the

be more consrstent    proposed changes were

with the TR.          incorporated as-is

14      15         28-29 Proposed rewrite to   The staff agrees, and the

be more consistent    proposed changes were

wrth discUSSJon       incorporated as-ls

elsewhere in the

draft safety

evaluabon.

15      15         37-39 Proposed rewrite for  The staff agrees, and the

clarity and change    proposed changes were

reference to point to Incorporated as-is

approved TR mstead

of RAI response

16      15         47-49 Proposed deletion     The staff disagrees; see

16          1-11 consistent with       responses to comments 11 and

comments 11 and       12, above. The text was revised

12,above              to be consistent with disposition

of these comments

PWROG-16043-NP-A                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                      A-23 Prog111m ~1J8!111Hll.Offlce

20 lnternafloMI Drive

WndSQr, Con~I QBQOO

PWR'.oo:16CM3'-P. "Revision 2 Dock~ Number 99902037 January 16,~019 OG-f'Fl3 U.S. Nu~t;ar Rcgul~ory Cofl&#xa5;!}issio&#xb5;
        Document.Control Desk

11555 Rod-ville Pike *
        Rockville, MD 20~52 Subjccc         PWR Owners-Group

,PWROG,Commcnl$ OD tbc NRC Draft Sllfcty l<:\'llhption for            PWRoc..:.t604J-
                       '.P, Revision 2; .. PWROG Program           to Ad<Jress NRC lnformatfon Notice

2012--09, .. Irradiatioa Effect, og Fuel Asscjpbh* 'Spacer Grid Crush *strcpgth

for Westinghouse and CE .P>>'"R Fuel li@gruf' (PA-:AS0H69)* -
        Reference*
        - I_. Thall Snfely Ev~lunlioJlS by the Office ofN&#xb5;clenr Rens;tor Regulation for topicaJ repdn

PWROG-1604).,P, ~cvision 2, "PWROG 'firogram to Adflrcss NR<:'' Jnformaiion Notice

2012-09, "Irradintion EITccts on Fuel Assembly Spoq:r Oljd Crush Stn:pgth for

W~ghouse ~d CE PWR Fuel Designs"' Pressurized Water Reactor Owners Group

(PWROG); CMlc,1~1.86A~34). dated Aagu~t 22; 2018.

J\t thc October 17, 1018 meeting bi.'twCCI). !hc PWROG and NRC to dis~ the mnjQrcommcnts

Qii the NRC' Draft Safety Evalwstion (DSE) for PWROG-16043 .. the PWROG agree.d to provide

fonnal co_mments on the NRC DSE for PWROG-16043-P.

The PWROO has the following mujor comment.on the Droll Sarcty Bval~ion.(DSE)':
        Section*,.&sect; of tlie .DSE discusses *...1mo,yo-* legacy is~ nssocirited with b!R,C npproved *NSSS

yen*dor"analytical methods that are unrelnted*fo the purpose oftlris. Topical Report (TR):
        {he di~cuss1~n orlegaty.issucs alw iriclud~ concerns ossociatei,l with the NRC approved* NSSS

\l~dor analytic;nl methods_ ~*ure used.for.bciginning 0&#xa3;,lifu (B_OL) conditions. ,&deg;Jf'iliete ~;
        concerns with tliese metlioils ot BOL. they would upply to all;\ice~ who usecftlie methods to

support their ~ t licensing-basis. The_ TR.only addresses the end oflife. (EOLJ conditions., and

ooly !he PWROO members thaL lundt:d trn; proJect. havt>.a~-_s Lo it. 'th~ PW~OG is "tJ11;*upplicum

Il!questing approval o( the TR. not the NSSS vendor: In ooditi.on.: as discllSSed in.the TR. the NSSS

ven~or *~Yff<::ill methods are_ n~t being revised as pi,trt 9f the, PW ROG pr.ogrnJII <;locumented 'in

the TR. 'Theretore;the Safety E\'llluntion:for the TR is not the appropriate vehicle to CX?ffiIPtmicate.

to ,an NSSS vendor any* poteticlnf iss.uis associated ~th NRG approved analytical methods'.

PWROG-16043-NP-A                                                                                            November 2019 Revision 2

\I\IESTINGHOUSE NON-PROPRIETARY CLASS 3                                             A-24 US Nuclear Regulatory Commission Document Control Desk                           January 16, 2019 OG-19-13             
* Addressing legacy issues is outside the scope of the TR review and the PWROG should not be

billed for NRC review fees associated with these potential issues The NRC has a process for

addressing potential issues assoctated with NRC-approved NSSS vendor analytical methods that

should be followed, if an issue is identified

Neither the Final Safety Evaluation Report (FSER) for the APlOOO Core Reference Report, nor

the APR1400 FSER contained any Limitations and Conditions regarding the effects of EOL

conditions nor did it contain legacy issues associated with the NRC approve NSSS vendor

analytical methods

Therefore, the PWROG requests that the NRC delete the specific text in Section 4 5, Section 4 6 in its entirety and the assoetated Limitations and Conditions, Number 3 and 4 in the DSE

Section 1 4 of the Topical Report (TR) identified the seven (7) specific items for which NRC

approval was requested The PWROG requests that these 7 items be identified in Section 1.0,
        "Introduction," and their approval discussed m Section 6.0 "Conclusions," in the DSE

The DSE has been revised in several locations to clarify the use of the terminology "method," and

"methodology." Where appropriate, these terms were replaced with "test protocol," technique,"
        and "approach," to reflect the purpose of the TR and to provide consistency with other sections of

the DSE that use the appropriate terms

The PW ROG requests that the Staff revise the DSE to address these comments and provide a copy

of the revised DSE for PWROG review, and that tl)e NRC contact the PWROG with any questions

or concerns regarding the PWROG comments

Correspondence related to this transmittal should be addressed to.

Mr. W Anthony Nowinowski, Executive Director

PWR Owners Group, Program Management Office

Westinghouse Electric Company

1000 Westinghouse Drive

_Cranberry_Township, :eA 16066 If you have any questions, please do not hesitate to contact me at (805) 545-4328 or

Mr W. Anthony Nowinowski, Pro~ Manager of the PWR Owners Group, Program

Management Office at (412) 374-6855.

Sincerely yours,
         ~,~
        Ken Schrader

Chief Operating Officer & Chairman

Pressurized Water Reactor.Owners Group

PWROG-16043-NP-A                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                   A-25 U.S. Nuclear Regulatory Commission Document Control Desk                                          January 16, 2019 OG-19-13                                                                                                   Page 3 of3 Enclosures ( 1):
            1. Proprietary markups of Draft Safety Evaluation for PWROG report "PWROG-16043-P,
               Revision 2 cc:    PWROG Steering Committee Representatives

PWROG Management Committee Representatives

PWROGPMO

J. Sinegar, W

R. Lou, W

J. Jiang, W

K. Laswell, W

J. Kobelak, W

J. Andrachek, W

EiectTonically Approved Records are AutJienticated in the Euctronic Docwnent MIIIU1/lentenl S:,stem.

PWROG-16043-NP-A                                                                                                          November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                                A-26
                                8FF1el*L 1:18[ 8Nl:V     PR8PRIET,.R&#xa5; IIIF8RM,.fl8N

DRAFT SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION

2                          fOB IQPICAL REPORT PWRQG-lPH, BEYl&sect;IQN 2.

3               "PWRQG PROGRAM TO AOORE&sect;S NRC INFORMATION NOTICE 2012:99:
    4      'IRRADIATION EFFECTS QN FUEL AS&sect;EMBLY &sect;PACER GRlp CRUSH STRENGTH'
    5                           FQR WESTINGHOUSE ANP CE PWR FUEL Q&#xa3;&sect;1GNS"
    6                    PRE&sect;SUB!ZEP WATER REACTOR QWNER&sect; GROUP (PWRQGl

7
    8 1.0         INTROQUCTIQN

9
   10 By letter dated Feblualy 1, 2017 !Refwenoa 1}. Ole PreeNized Wiler Reader (PWRI Owner5
   11 Group fPWROO or Ile appllcantl. submllled 10 fie u s. NUcleer Regutatory CommiS!llcn (NRC)
   12 stafffcrNMew lioentlng 1Cpic81 l'lp0rt(TR) PWRQG.16043-P RN!lon 2. "PWROG ProgRun ID

13 ~ NRC lnfom,aton Noice 2012-09' 'IIT'lldtl1lon Effects on Fuel Aseefflllly Spaalr Gl1d

14 Crush~* for Wedfll1IOUSe and CE PWR Fllel O.p' (Ref.._ 2. llencllb'tl

16 refeffed IO l!IS !tie TR~ SUbsequant letlers dated Merc:h 27. 2018. May 16, 2018. and 1,1,rf 16.

2018 (References 3 4. and 5. respecilvelyJ. prOllided additional infamation lhat supplemented

~! 111e Information provided In Reference 2 The TR                   i

*. ,er:L

1, , *11 "
                                                                                      .Of",.,f -* * -
                                                                                           ., - ,* ,,
                                                                                                                ,
                                                                                                          ~J' ' ...

I19
   20
   21
        ,,;_ *,.                                    ~            ~           .

w::AP-9401-P-A (Reference 6) aml CENPD-178(Pl. Rev 1-P (Reference 7). to assess lhe

describ~ ITT  Commont.d [1ft: S.e Sedion 1.3oltheTR

Ii

structural integn~ of fuel assemblies under faulted condition loads

Comm<<1ttd 1021: Thft ta>I "net nN$d duo to tho

26                                                                                                               t ~ to the prcw..x,s .ss,*tence above

27 2.0         

==BACKGROUND==
28
   29 Selsmic and LOCA IM!rl1S can reut In external forces applied ID the fuel ll59efflblles

30 {.8.IJ., lihaldnD lll1Cl.lor vlbnlUlfy ' - l - Thenlfa'e. applfCls118 mUll ewlua18 the ll9I Ull8lllbly

31 strudnl 1'81fl01'1* under,-. candlons lo ensn lhllt regulatory ~ we met with

32 f11SPed to QQl1RI rod lnsatlbilty and oare coolablllty. In p..Uall*. Ile spam- grid

33 perfo:mance ia u.awd to defllnnme tf pfHtc derormetion 11 lllCl)tC1td to occu-. and Ile fuel

34 ftl<<llbly vlbmloo behavior Is quw\11*1. Most PvVR plwlts cunntly u1111ze 11e NRC lll)IIR)Yed

35 1e1t1ng end 111t1y111 mellodologi" descnbed in ~ & tnd 7 for WMtnghouse encl ce

36 11111 deSigns, reapedlv91Y.

37
   38 The NRC reviewed and eppRMld References 6 and 7 based on the regulatoy gui/Jllnce

39 p!O'Mldln Appendix A toOIIIC)tlr4.2dhSlllndard Review Plan (SRP orRMnnce81. OMI

40 aaunpllon III the SRP Chapter 4.2 Appendix A guidance Ill the tme. wllld1 19 also in lie

41 OJlleT! l1!VISIOII tran 2007, IS tlat beginning d lifefBOI.) Is 1118 lme Ill wllictt the aushlng 108<!
   42 for f i e ~ grids would be expedlld to be II e mlnlm1111 This 8Sllllllp1ion wa based C11 tie

43 fact that lrradlalQi tends to ceu111t snngllening in metals and elJoys in addllon to

44 embltt1!anent Other effec;ts llat aise due to use In e niectcr mav lndude growlt. cladding

46 aeep, and com>sicn. The lnaeue In strength was ecpec:lld lo men thin offlet Ile other

ePFlelAL 1:19E 8NLY      PR8PRIE'l'M'f INFeRM,.fl8N

PWROG-16043-NP-A                                                                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                         A-27
                               8FFleh,.L l::ISE 8HLV          PR8PRIEfAR&#xa5; IHF8RMAfl8N

-2-
       1 elfeds IISSOdllted with lmldiated grids. Since appllasnts typicatly W!fify 1hat the maxnnum load

2 mipalalced by 1he spacer grids dt,ing LOCA and seismic evaits wlft net exceed the Ollllilll

3 load. 1158 of BOl charadlaliSlics was conadered ID be consecvative.

4 Opa1l1lng e>ip\111ence tha1 came ID Hght in lie mid-20005 led 1he NRC &1aff lo ques11on 1he

5 U&UllfJlon '11lt the 511_. grid &trudural pllfamance dll'1119 LOCA and slilrnk: went& would

6 l1Clt degrade signiflclll'llly IIS I result or lrreclidon. The NRC 1Ubsequen11y ISIUed Information

7 Notice (IN) 2012.-09. 1lflldilllion Effecls on Fuel As5embly Spacer Gnd QU&h Snnilh"
       8 (Reference   sn    Tiu IN liss 58Yeral facb1j 11at c;an affect the 1t1ue1un11 Slrenglt o4 the Ip_.

9 grids and singles out spacer grid sprtng rtlaxatlon as one that can have a slgn111cant effect on

10  the fuel IIMllfflllly mechanical ctlaraetensties and Iha sp_. grid ahngtl. ~ no speclllc

11  lldlon or response was required asa redo4111e IN. the NRClndlc:aledthatreciplentswOUld

12  be e>cpeded lo rllllieW the Information fOr applicability and consider appropriate action to avoid

13  Similar problems.

14
     15  This TH 1s the applicanrs proposed approac/1 to generically address the issue identified 1n the

16  IN for licensees that use WestinghOuse or CE fuel.          w   1_
     17
     18
     19                                                                                                        Commenlod foJJ: S..Seclian t .3 oClho TR.

20
     21
     22
     23
                                                                                                 _,....

24                              *-   it , t,   '"       r d.*m in ,    in a S1 mliar manner to the NRG

25  approved still water damping ranos (as described 1n References 6 and 7).__..... provides a

26  means for Uceosees to recover margin lost due to Iha e led of space!' grid spring retaxa lion on

'Zl 1he fuel assembly mecnanic:111 dlal'adensllcs.

28
     29  In rummary. the eld!llng NRC ai,prove(! tes9ng end analysis me1hodologles wffl eonttnue 1o he

used, wi th an previously established limitations and conditions, ~ W I this TR -
   I~33
     34
     35  3.0       REGULATORY EVALUATION

36
     37  TIie 10, *energy," Of tie U.S. Code of r:.dtttal ~u/alJons ( 10 CFR1 Part 50. "Oomestc

38  l.lOensing of Production ano Ullllzation FadHtes.* Section 46, "Aoceptanc,e crflel1a fClr

39  emergency core COOiing systems for ~ghf.,water nuclear power reactors," oontatns reql.irements

.co for lhe emergency core cooRng system (ECCS) at oomffleldal power plants. In p!1111cular,
     41   10 CFR S(U6(b)(4) requires the! "(cjalculeted changes In core geometry shall be such that tie

42  core remains amenable to cooling.* Ar'ff failure in the strue11Jral Integrity of the tlJel assembffes

43  will typlcaRy change tl'1e core geometry, 11nd Ile po&Sibiuty needs to be evaluated

44
     46  The reg!Jdon at 10 CFR Part 50, Appendix A. "General Oes1gn crttena for Nuclear Power

46  Plants." Ganlral Design Crilencrl (GOG ) 10. "Reactor design," stateslhet1"9reactarccre ...

47  Iha* be desgned wrth appropriate margin to assure Iha! specified fllll tfetlgr1 flmlts arE! not

I 48  exceeded dunng ... anticlpated operatonel OCOJrrences: Wlhln the contllll of L(Jt." ino

49  Nilmic events. th1S 1& impllcily ~ by ensurin!I adequate Olft COOkdlilily.

50
                               8FFIE!l"'l 1::19E 8NLY         PR8PRlffARY IPIF8RMof."8N

PWROG-16043-NP-A                                                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                             A-28
                            8FFlelat.L 1:119E 8NLY       PR8PRIETAR'f INF8RMAT18PI

-3-
    1 The regliation at 10 CFR Part 50. Appendix A, GOC 'Z7 . "Combined reaCIIYity control systems

2 capability." states that 'llP,e readi...tty cootrol syslems shall be designed to reliably (control)
    3 reaelivity changes

* One of the primary reactrv,ty control systems at airrent WEC and CE

4 PWR plant5 ls the rapid insertion of con1rol rods to add sufficient negatlve reactivity lo shut

5 da,yn the reactor Reliable operation of lhls reactivity control system Is condi11onal on the

6 capabltity to insert the control rods. Vibrations or stn.tctural deformations may impede the

7 control rod movement. and need to be evaluated.

8
    9 The regliation at 10 CFR Part 50, Appendix A. GOC 35. "Emergency core cooling." restates the

10 requirement to maintain adequate emergency core cooling capability. which can be affected by

11 1he core geometry as discussed ,n 10 CFR 50 46(b )(4 J(see abolleJ

12
   13 The regliation at 10 CFR Part 50. Appendix A. GOC 2. "Design bases for protection against

14 natural phenomena." reqLires safety-related structll'"es. systems. and components (SSCs ).

15 1nduding reactor tuel, to be designed to withstand natural phenomena (sudl as eerthquekesJ

16 without a loss of aipa1>1llty to perform safety functions This GOC also requires consideration of

17 *appropriate combinabons of lhe effects of normal and acodent conditia1s wilh lhe effects of lhe

18 na.lural phenomena

* For example. a LOCA may be caused by a seismic event so

19 considerabon of the effects from a canbination of these lwo events may be appropria1e

20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   ~                                                                                                       eof

33
   34
   35
   36
   37                                .!_he primary criteria are related to ensunng that core coolatllllty and

38 control rod lnsertability are maintained.

39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
                            8FFl61M. ll&E 8PIL&#xa5;          PR8PRIE1'M&#xa5; IPIF8RM.t.=1'1811 PWROG-16043-NP-A                                                                                               November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                               A-29
                                8FFlelAL t:ISE 8NLV        PR8PRIE'FAR'f INF8RMA'Fl811
       1
      2
      3
      4  4.0      TECHNICAL EVALUATION

5
      6  The intent of the TR Is to

7                              ~
      8
      9
     10                  ,n References 6 and 7 by focuSing solely on the specific parametin 111111 wOUld be

11  Impacted by 1he EOL Issues identified In IN 2012-09 (Reference 9) As sueh. the TR narrowly

12  focuses on three primary parameters*
     13
     14           The allowable grid Impact S1reogth (
     15
     16           The lie! assembly modal frequendes (
     17
     18
     19
     20
     21
     22                                                          land

Ii 27
     28
             1.                   tuet assembly flOWlng water damping ratto, [

I         ------------
         As a resut. some ot 11le areas from SRP Chapter 15.02 are not appNceble In particular. the

I 29  analysis metiod_              described in References 6 and 7 are not being modffied. only the

30  empirical detemllnaUon of key input pararnelers Therefore, the accident scenario desaipUon.

31  the phenomena identification and 111r1klng. and code assessment from the pr8\llously appro\led

I 32  method *            remain valid. The NRC 5taff review of the TR focu58d on two of the specific

33  areas descnbed In SRP Chlll)ter 15.0.2. as described below;
     34
     35       t. Evalua,on me1hodology - Iha prop05ed testing and data anlly*s

I 36                ::,ec            *
* lnciU<llng any potential limitations 11) iieir applicability

37
     38      2 Uncertainty analysis -1he applicanf s 1Mlua11on end propagation of uncena1n11es in Ille

39           analySIS rl test data to obtain recommended values fol' Ile key pMamelefS.

40
     41  In addt1ion, the NRC staff considered whetier ll1il apphcant pf'Ollided adequate quality

8SS1J1"811C8 (QA) and docu:nentation support for tt,e proposed "'n.._......_-=.....,.....,.~.J,-..;...a- I~ 46
     47
         *
         _

* ll! z1e*     ~*                   . This aspect IS not explicttly discussed 1n detnll for lhis

safety evetuaion (SE) beQluse the documentation of Ille proposed

cap1Ured by the documents l"elliewe<I by iie NRC dUring an aLldl dated Oclober 17. 201 7 (Reference 11 ) IW1d 111111 were found ro ha\/8 been approprllltely summwed or olhelwise

ch11racteriled In 1ne TR. The tes1ing was petfonned under 1he auspices of lhe S11111e QA

_
   I 48  program L                            tesling ""'-i'reviously ~                                        - to

<49 determine the key parameters for SOL grtds and still water dllmpmg which Is acceptable . As

8FF1el"L t:19E 8NLY        PR8PRIC,ARV IHF8RMM'l81*
PWROG-16043-NP-A                                                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                               A-30
                                 8FF1elifct: 1:18E 8HI.V    PR8PRIETAR'f IUF8RMATl8H

- Ii -
      1  sum. the NRC staff accep111nc:e of1he lldequecy of lhe ap.pOcant s ~, r-~,,,, c-,
      2                 * ~ and ~ analyses implldtly lndudes scceplance of !he applicant

3  clocumenlallon assaciat8d WIii 1181 area

,4
      5  4.1       EOL Grid Simulalion

6
      7                                              ,~~!'~ TR ilJ!                              .-_j;:-
      8                   * . '"'- charectenz-abon of the in1piacl of ,rradiaijon on the spacer grids SRP

9  Chapllir 4. 2 Appendix A (Rafe(411}g! BJ ates_.. postible tl'l"llddon.ffle effects 11:1e11an1
    10   to tPac:er grids, Ind condudes Im the oombinect tmpad would not be exJ**I to lea<! to a

11   more conservetve result Thl1 logic rel1S mainly on Ille fad tie! lhe sgnlftcent increase In ',lelcl

1'2  strengll'I for lhe spacer grid maierlel wlll more than otrset ttia reldvely mlnor lllfeds from !he

13   temaJntnsl elfeds As deaC:rlbed in IN 2012-09 tRefsenoe 9) operating e,cpert8'lce i'las snawn

1-4  !hat spacer grid spring rflllllUl,ai can have a sif1n11C8nt adverw effed on &pllClllr gild '1renglh

15   and b!l 8S9efflbly medianlea1 ct,llllldenstics. I

16
    11
    1a

19                                                                           I0ttw11en gnd spnng

20   rwlaxaton. !he baStc nsessment In SRP ai.pler -4.2 Appendix A that IITlldlllllon-<<'*'led effects

21   are bounded by !he increase in Iha yleld Shflglh or the ~ grtd m!IWlal continues to be

22   apphr:eble I

( 23
    24
    ~
  ( 26
    'ZT

28
    29
    30
    31
    32
  ( 33
    34                                                                  I Ali diswnad ll't Vie (X'IMXISl)lngr'IIPl1,
    35   1he NRC 51aff found that the focus on Ile~ spring rMxa11on phenomenon as Iha qy d!iver

36   for the n ~ t i W llellllllor ldtntfied 1n Spacer grids al EOL retatve 10 BOL is

37   apprq>Mtt. How_,. the materiel enc! geometry Impacts of Iha lhennat retaxatiOn process

38   must tie reesaillbly Similar 10 Ile imldialloo-lnduced lmpeds Ila! aw being Simulatlld

39
    .co

41
    42
    43
    44
    45
    ,46                                                            )Therefonl. Ile NRC staff requested ldl1ittonlll

47   infort111111on ttom 116 appllelml regar<ltng lhe lhe!Tnlll relaXllliOn proc:edUre used a, prodllce tt,e

48   simulated EOL grids. l

,1g

50
                                  8fflQAb ~IE 8Nb't         PR0PRIEMR'! INF8RMA'R8N

PWROG-16043-NP-A                                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                 A-31
                                 8FFl8blcL 1:18[ 8NI:&#xa5;          PR8PR1Ef11R&#xa5; INF8RMll'fl8N

- 8-
       1
      2                                                                                                              I~
      3  appllalnr1 l'fllillClll'l8 also conftrmed 1ha! Iha ma!llrial stnldll"al dlaradaillllCS of the limJll19d

-1 EOl grl45are Iha same. or sllgl'illy CCllll8Mdlve. relatlVe ID the BOL grfd6.

5
      6
      7
      8
      9
     10                                                                           I Thanl l n tome 19\111110!15 whent

11  a spacergncs ISflllJ)OSe(I ID a Sllangly l'IOIMfflifolm newon lklx. such as fuel aS9efflllly loedlng

12  locations et << ,_ the an pe,lpl'tely The NRC stall asked the applictnt to adcnss Ile

13  potental lmpac:t on lhe gr1d fallum medlllnlsm caie to non..random gradients 1n gap size 1'181
     1,1 may be correlated with S1lep neutron ftuX gra<hnfs. I

15
     16
     17
     18
     19
     20
     21 I 22  FinaUy.         * "           2 1 al Ille TR descnbed hoN Ille lllfllet average gap SIZe was

23  determined for II given spllClfJI' grid. (
     24
     ~
     26 Z1
     28
     ~                                                                                                                I

30  lritldecjulle lnfatn~ WI& given In fie TR to dellne lhe -                 d appltalblUly fCF 11letrtpolaton ot

31  a glvel Ill of PIE dala lo Ile ga,n pq,uatton ot EOL. g,td spacers of Ille ane de&lgn, l!O the

32  NRC s1alf 19q11eslld 1hat Ille appllcant Q!aradefiZe how PIE dala sets are generaay clellned In

33  order to achieve 1heir lfltlnded purpose

3,1
     35 I 36 The a.ppUeanl respor\de4 Jct Reference

*
                                                          *~an      llllpl*1at1Cn of 11'18 Sllltislical

iJlldel'lylng tlleir dell!mllnetloo Of e ttrget gap size for Ille Sll!Wlated BX

~   Qllds. [

38
     39
     40
     41
     42
     43                                                                                            )lllslsa~
     44  CllflSelYri,,e approad1 to l!fl&UIV that Iha aY11rage 118P sizes b t1tt ~ EOL s,klli YilN

46  bcund the 1WlflQe gap sizes for llrldialed grid$.

46 A7
     48
     4i

50                                                                                              lffle NRC &1811
         8!Tf!M how- lhe applicant did mt describe !ICM' Ille rod flumUp$~ wlfl

PWROG-16043-NP-A                                                                                                        November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                   A-32
                               9FFl81M: 1:18E 8NLV         PA8PRtE'FAR&#xa5;IPIF8AM,t,ll9N

-7-
      1 tie PIE lm!a5U!'l!ll!!.'n!S wout!f be tlsed to dettne 1he area d appltc:abllly for fllel assemblies

2 qtallted          '                                            In II Sllpll1lte RAI respmse {RAl-2.

3 documented In Reference 4 ). 111e applicant provlde<11nfarmallon lhllt shows llat Ile varilllton Ill

4 111P 5iZeli fer Y9l)ffl9 bumUpl; near EOL can be el<p9Ctlld to be minor rl!ldve IO lhe inherent

5 randomness In g p sizas within a grid. In addition. 1he NRC staff nolld l18t fie

G ,* '"(c,-,;t~- ~ ~ d111Cl'1bed In Reference 7forlesling of CE design fuel assanbllas includes

7 madlllif!Q fgr both BOL nl EOL gricS.. I

8
      9
    10
  ( 11                                                                                       I Contistenl WIii INS

12  IISS89Slllefl1. 1he 19SU11S flffll the letllng dll\Cll$Sed lf1 sections 4.2 and 4.3 d Ills SE !ktO<< (
    13
    14                                                                                   ) Th.-.be, any valetions

,~  In bum14> tor the ftlel assembllesU!llld IOeb'81n P1E m~entsN!!l!1!\le1!l 1he Olll!l'III

( 16  populallcln atW aaembllesbeing qualft ed                 _         this                            would not

17  result 11111 signllcant dlllllrence In IMng8 gap s,ze. cena1nly much less than the inherent

1&  consarvalsm In the ffllrllS1 llelwan t h e ~ maasunid gap &Z85 and Ile target gap liile

19  b' Ile slmullled EOL gdds.

20
    21
    22
    23
    24
    2!I

26                                                                                      JM a l'89Ult, tie NRC

'Z1 staff touno Ille pn:,posed lpl)l'Olld'I to generate !imUlllted EOL grtdS for use 1n leStng Ir! Neu d

28  lmidlated g,ids lo be accaplabl1.

29
    30  4.2      lpacer Grid lmpec:t StnNl!flh

31
    32   ., . .               2 2 and 2 3 of the subject TR disa.ui5 lhe 11Jpllca1ltn Ill the approved 1leSting

33   and data analys,s ~                            from Referellce5 6 lllld 7 IO determine the allowable

34 gnd 1rrwact s1renQ1h for ff1e simulated EOL i,id5. [

35
     36
    37
     38
     39
     40
     41
    42                                                                                             )The NRC staff

43  understanding or the approval request rrom the applicant Is that this _.- - ~
    <<    cntei:100 was                   - merely for dem=auon purposes. ~ not                             . submitted

46                           , to _       _                                      
* J *r i Reference6
     46  ,.               In response to a RAI from the NRC staff ( Reference 3), the apphcant con finned

47  that ttus was the case Therefore. this application was Judged to be ecceplable solely for the

I 48   purpose of prOY!dlng a more consistent basis for comparing                           ~ P(ailJ for

49  wastan~* d CE kl d8$igni.

50
                               BFR&tAk Wit 8NLY             PR8PFUETAR&#xa5; tNF8RMAfl8N

PWROG-16043-NP-A                                                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                              A-33
                                  8FF181111.L 1:18[ 8Nl::V      PR8PRlffM&#xa5; U.F8Rlll,l,'fl8N

-8 -
       1 The simulated EOL i,iC1S contain I

2
       3         J The NRC &1111 VIiified by iMpllCllon gt the applican(II l8't doaJmenlalion Iha! the

*
       5 failure medla"lla!I fDr Ile simtJlaled EOl grids was the same as 11<<1 b the BOL grids.

Theralore. I

6
       7
       8
       9
     10
     11
     12 I 13
     14
      1&
         n,e NRC st!lff verffled 1ttef1rte ~
         _                           References fi tnd 7 wera

grids In addition. the NRC staff

appn,ved~ end data !Nlysis k::~~
                                                                    _....,.1a11111y 8l'PIICf 10 Ile simulated EOl

found,_,.._.._ 81d911 llal Ille afol'ementoned

.. 11111u,rn llf)pflomle to tt,e i,eome1ry of t,e slmufllted EOL !Jl1ds, I  16
     17  Ttwrerore       .e NRC staff found 1he ,                t               1,                    , * * - P(aitl

,~
     18  to be ~ for UN In analysis of lhe simulated EOL lids

19
     20  4.3      F..i AAM!bt, Mechanical Charac:tvri.ilca

21
                              3 of   e TR discusas the a.pphcnon of t i e ~ '"log and                     mu analysis

, .               ..           -    .   R e r - 6 Md 7 IO detllmllne 11111 lltowtbla gltd Imp.et

24  S1renglh for tne simulated EOL gr1da. The TR - - . "8t '(flhe M?M '"1 pn,tocol hU been

2!I previOU!IY applied to Clllffllt Wlsllng/1CUSe and CE l'WR W deSigns fa' Bot candltons. 11111 I 26  tllat , ,he lll!St p"*>COIS 11'9 dl!lllerlbed In NRC-appralled TR!I. ... With a Clllllcn ID References 8
     'ZT ll!ld 7 Tnererore. 1l'le TR desty Cllll'llt:tl!ll 111, 1Mnt plllCl9Clft for lht Mmultlliecl EOI.

28  grids to be ldenfail to the pnMOUSly IIJJ)l'CMld IIIS1ng procedure desa1bed 111 Reler&neeS 6 aid

29  7. "'1tl 118--., ht the grids are !lmLillled EOL grids es discussed in 6edlon 4., of lhis

30  S6
     31 f 32  The lllslng            *     ..,         '-- desaibed in Rafetaica 6 and 7 W'9 pllma1ly telit5
     33  cmduded on the strue1Ural members cA 1he iiel assanbly rod fNI I p - gridl. wllh no tn1S

34  dirlcily impeding the W rods. N. BOL. 1h11 grid spnngs exert a frictonal fQll:e on 1"1 ll81 ~
     35  so ttie 11p41ctr gtida end fuel rods-. mechW'lically ~eel i:i $OIi!* mint. IMin!J tie ruet

36  1!IMl'l1bly ..ttntion test9. 11* fuel rods contribute to !hi llet eaembly ~ pertormence

37  by vrt.1a o t t r u ~ coupUng. I

38
     39
     40
   J 41
     42
   ,~
     43 I<<
     45
     48
     49  4.4      Pnicedunt lo o.t.rmiM Flowing Water Damping Ratio.

50
                                  8PFlelAl 1:19[ 8NLV           PR8PRIE'l'MW lltF8RMAfl8N

PWROG-16043-NP-A                                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                            A-34
                                8FFl81ifd: tf8E 8Nl&#xa5;     PR8PRIEl'AR&#xa5; INF8RMMl8N

1 __                   4 of lie TR descltles     r                             1
     2          ..*. ~ ruet assembly llorilng weter damping ratios and apply them in lieu of pre\llous:,
     3  awroved suu water danp,,g mos mdl8'1ld81ze the 111411 .-n1>1y mechaliall ber.viar

4 <tin,g sellimlc Md LOCA l'tlllt5. Sine>> !he dampilg r11to Ille to 1lowing walllr is pPedild IO

5 be hlghe-1han hdfar stll wlllar. tri5 approach could help l9Cllpllll9mwgln IOII di.lei> the

G  rmpact of gild space!' r.fllllalal on the fuel nsembly stlftheu. I

7
      8
      9
    10
  1 11
    12            <           4 1 lhrouQh 4 3 delCribe tie last appardJS end dale c:olec1ion peifcrmed IO

13  suppon an emplliall determtnll1fon of the tc,,mg water damping rauos [

14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26                                                                                    JStrite Iha 1oSs

Z1  coeftlcients for the fuel asem1>1y de!9'1s 11111/e been apprtM<t t,y the NRC for use III Oller

28  1111111Y9M and WC1IIII not be e,cpeded to vary ~ as a result Of tne uee of !IIIIUllted EOL

29  grids. Ns epplOIICh 1br delennfninO flaw velociles 1h'ough 1118 llel assembly Is acceptable.

30
  I~33
    34
    35
    36
    "ST

38                                JTes1ng pe,fOlmeO on simllllr llel IISSeffll)ly Cle1igns Ullng a r-.,e Of

39  dllferlnt approedle&. as d0almen1ad il1 Refermces 14 and 15. ~h!ld cmllstent resuftl [

40
    41 I:46
    46 IMt pRJpOlllll1 Ql'l'a,Uy 11P1>roved

47  The ftCMlng wtter damping l'llllo correlallon was d9Y91opt<I based (
    48
    ,w

50                          8FFIEIAL 1:18[ 8NLY      PRBPRIEMRV IHF8Af1Yclt8N

PWROG-16043-NP-A                                                                                                November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                 A-35
                               8FFl8btoL tl8E 8NLV           PR8PRIETAR&#xa5; IHF8RM.lcfl8N

- 10 -
       1                                                                                        1Thffl!foR!. 1tlel'e

a      wHt be no lnconsl!Jlenc:y tn the appltcation Cl damplne rattas far flllll assemblies et ditfllrllnl

3                                              blfflllP condlllOflS.

4
       5 Based on Ille dala cdleded l'Orn tie tests. a damping 1111io was detemllne<I for each 1est based

6 en dasslall Wbratioll lheo,y (
       1
       8 g

10
     1'                                                                                                          l

17  Since lh* use of lower dempmg ratios In developmgV!a c:oriellllion Is conservatlVI. lhts 11/G . i

1.1 ecc:eplllble choi4lll il mam

14
     16  ~      o, ':I pl_ 4 Soflhe TR d~1he data 811IIJytiU1)proad, used to<<eten'nina

18  boundlnQ .::orrelatiOns for eadl ful:4 assembly desigll This appl'08dl can t>e suftllllwed t!Ws- I 17
     18
     19
     20
     21
     22                                                  JThe <M!nlH approach appears to caplUIB the l'8lellal1
     23  dependenc:ie$, hoWe\111'.   ltllft flli no propagallon Of Ille unc:ertllinles due to scener In data

24  1hJOUgh lhe sleps noled ~             t

25
     28 ZT

I 28
     29
     30
     31
     32  Tne applicant responded In Rerfflnce 5 wlttl information tndlca1fng 1hat lhe fillfng eppn,ecn

33  used to delermlne the bOLllding a.irve was fundamenlelly a fleSI esttmallil approach to derive

34  1l'!e 600 "F curve based on lie selected dllla set 1
     35
     36
     37
     38
     39
     40
     41
     42
     43
     44
     45
     46
     47
     48
     ,4g

50
                               8FF1e1Al l::,BE SHI:&#xa5;         PR9PRIETAR*FIHFSAMAl1BPJ

PWROG-16043-NP-A                                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                     A-36
                                 8FFl8bl,L 1:18E 8Nl'/      PR8PRIETAR&#xa5;1NF8RMM'l8N

- 11
      1
      2
      3
      4
      5
      6
      7  Finally. O'lap\er ._, PfOPOH5 use of a lloWlng waler ClamJ)lng rato COffll!lllion bnect on Ile

8  [          JfUIII usembly 4ftlllll as e genern;ally bounding correlabon lh&t ,nay be uHd w,lh any

9  flJ4!I aNfflblV dMign without fW1her Jus11lcatlon The ,              .. i..i, n-ho .10109*1 diSCusMd abO\lt'
  110    may be used to dlMfop fliel !ISMll!lly delllgn specllic corr~ om,. but-lh                           }
     11  correllllicn rs proposed for.- as II boulldln9 a,ive for all Westinghouse and CE llel desigl!S

1"2 The juSllflcation prcMcled Is ll'tat the [       llJlll ..-mbly design propONCI fa' !tilt I                 I

13  ~ plant CO!llalns 1111.lmba' ~ ~ d e s i g n ~ tlUt testnlSIIIS shaw lllat

14  me ftCIWlng Wetllr damping ra1io is Vf1CY Similar to ll'le I             f flJel The ce 6Jel Cla5ign tested

15  tied(
     16
     17                                                                             Inn betlal/lOI' Is bOllflded lly Iha

18
     19
     20                                                                                   I Th<<efore, ll'NUlmllality ill

21  resull5 ilS not 51.uprisng.

22
     23  In order to estabtlth thet 1h11 proposed C01Tel.iion can be USlld as a gsnene bounding C1Arvt. lW

24  eippllc:abllty 111ust ba lilnl'*' t o ~ gilds with very 111muer gaomatry Cfllll1ldlnne& nus ,s

25  accom!)llshed Ille a ccndltion to lie TR lnfornllllon submiUed in Refelfflces 14 end 15 pnMde

26  infOrmafion for 01her PWR fuel assembly desgns !hit 6IJg9IISls that. in fad. the {
     Z7
     28                                                                                                   l Aalongeis

29  1he geometry c:ttaract<<i!llies of the 9fl&eer grids associated with II different fuM assembly do not

30  dlfler&lgnlfia.lnllyfrom 1he RFAIRFA-2 5jlllcergnd. tne NRC $lalf findsthat reasonable

31  clliSUlllllCe 8lcists that olhar fuel as5elllbly dflllllllS wlN have !lowing wafer clampinl} ratios near

32  or ab<Jl.'e trnr ~ bounding c:uve The proposed appkation lndudes use of a mlnimt.m

33  Vlllue for the enalyas dutllfion re1tler th111 e morei realistic l!IYenlge value, Whidi inc0f)l0!1lln

34  Slllllle lldd1ior'AII ooneeNetiRTt ttat OffSllls the polalHI fer slighly lowerlGM'lng water damping

3{i ~ioS tor some fuel -,t,ty designs relative IQ the r:,rqiosl<I bounding t\lMI.

36
     37  Based an ,i. tnforrnatlon prwdfld In the TR. as supplemenled IYj responses to Mqtles!s for

I 38   8ddi8onel infolmllllon trllm 1he NRC stall, Ille 1Ntlng protocol anct data Malyss                  * * *..;.:...,
     39  describe<! to dffln'Alne appropriate lloWing Waler nlllj)il'(J ralios-detetMlned to e

40  eppn,prtate for tlll!il' 1ntendec, pt.qJose In llddltlon. [

41
     42
     43                                                         JThis l8lter cond!Mon was caplnd in Sedion 5.0
     44
     45  4.5        Analytleaf Appllcetlon of the Flowing Weter Demplng Rlltios

46 j 47  __      . _,        ~ 4..8 and 4. 9 Of 1he TR lftn;aibe wheo end how Ile flowmg water demping

48  raUOi can 'la Utilized in SllsmiC and LOCA a n ~ relpedl\'ely. The pnmary parameter us.II

49  to establr.ih the appl'Qpriete Vllue 1i0r the flowing water dempmg ratio is Ile fluid velocity lhrough

50  Ile fu/11 assembly For a QMllt pllllll. tllls parllfflMlr is dil'tt;W CXll'flllalN with 1M on 11,-.

8FF161AL ll&E 8NLY          PR8PRIE'FM&#xa5; IPIF8RMNR8tl

PWROG-16043-NP-A                                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                               A-37
                               8FFl81AL 1:18E 8NLV              PR8PRIEOcR'f INF8RMA'Fl8N

- 12 -
       1 Tllemcre. the dlscussicn In the TR prtmanty fOQISeS on 1he c11aracte11zat1a, d a boUndlng coie

2 law for any given time Of lmerest durlng the event bemg IIIIIIV.zed Once an apprq>(iate IIQ/ue

3 ls detemlllled. then plan~fic lnfomiatloo can be uaed to llllil8bliSh an appropnate flow

4 Vllod1'/ to UN will the flOWing water clamping ndo oorreldon. J

~
       6                                                    JIn general. since lower tow velocities n11Ult In !ewer

7 11owini wafer damping ndas, any fador that may lead to a reduclioll m lha core *a.v rate win

8 proi,jdamcn~tlve-..-.... Fct,ltffnlf18lys11,.f

g

10
      11 fl For the lltl!mic analysis. two 1c4y.-ptions -Made Ill) Mmiza 1M IOIIII core flaw. Flltit. f

13
      14
      15
      16
      17
     18'
      19
      20
     21
      22
      23
      24 Seco111dl';, (
      25
      26
     'D

28
     '29 f 30
     31
     32
     33                                              l At 1111 Ume. the IIOW!llg water aamptng 1'1110 will be at a

34  ITinlrrnrn. and IC1N8f Ulen the 8Yfflllle ffowlng Wdil" damplngra11o 1tlr lhe lnllMI, Since U1ese

35  assumptions boll ad 10 mirimtze the ffowing water demping ,..tio, u,ey are comel\lftve

36
     37  For lt'le LOCA enal'y$i$ the care flow raleS -            to t,e ob1alned directly from 1he LOCA analyses

38  IIS long as axial flow IS maintained.       !
     39
     40
     41
      42                     Jllli e reSlit lie NRC slaff !nds that 1be lOCA 8fl>>/SIIS condillans are an

43  ~ SOtRe Iara bounding                    an ffllW rate forlhe purpose of detem11nlng ffowtng waler

44  damptng ratios.

45
     46  A sacond ttmilalion of 1he ft owing water dllnpmg l1llios is 1hat the dilla used as a b8si1J for 1he

47  CCJ!r.lation were based on Single phae liquid llow Unugn aw a-bly. The condltian.i

48  unaer wtnch the llowlf19 walftr damping ratlOs art expeded to ba Cl'ld'~11111c events and

I 4a  the 1in,1 ~i sec:ond 'Of II I.OCA ~ not expected to invotv. \wo ~ flow in t,e cont.

~ . the         m   <kll!s not lllCpliCitly fitnit tie use of ftONlng warar dllmpll'lg 1'1!1!09 to ~ e phaw

now CQ'ldlllOns. so e amilauon was indul1ft01n Seellon !i.O to M91.1n! tnet. If o, 11 ,,,r n, , r1
                              8FRetAL tl&E 8NL'/               PR8PRIE'FAR&#xa5; INF8RMA"fl8N

PWROG-16043-N P-A                                                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                       A-38
                          8FFlelAL 1:19E 8NLV       PR8PRIE'fAR'f INF8RMA'fl811
                                                     -13-
    1 .u.    q   pr,giilt5111ai1Uel1f/ is applied to condtions that dl!lltate from expectations. the

2 cooelalfon will not be used outside the bounds of its applicability.

3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17 The guidance prD111ded In lhe TR to credit flowing water damping In seismic and LOCA analysis

18 was reviewed by the NRC staff and determined to produce accept,bly conservative resifts for

19 lhe expecied analyss conditions. Therefore. the NRC staff finds the proposed application of

20 11o.ving water damping O'edlt for evaluation of fuel assembly mechanical bel'lavior during

21 se,smic and LOCA events 1o be acceptable .

22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
                           8FFl61AL 1:16E 8tlLY     PR8PRIE'fAR'f INF8RMA'fl8tl

PWROG-16043-NP-A                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           A-39 O'l'ICIJIIL tl9! ONL, - flllliO,iU!TJllllli, IN~OllliMJllflON

-14 -
     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
  ,~
    18
    19
    20 5.0       LIMITATIONS AND CONDITIONS

21 Some llmitaUons and ca,d,bons are necessary 10 ensu-e thal the          ,        ! -         iRr ,
       ........___           discussed ,n the TR Is lim,ted 10 the applications for which It is valid.

24 These llmttettons and conditions are listed below

25
    ~
   I28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49 s.o       CONCLUSIONS

8FFlelJIIL l:ISE 814LV    PR8PRIE'l'JIIRY INF8RMilc'fl8N

PWROG-16043-NP-A                                                                                          November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                         A-40
                             8FFle1"-L l:IBE 8NL'f       PR8PR1~"-R'f IHF8RM"-Tl8H

- 15 -
     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13 Since 11le TR is not propoSing eny Change to 1he prelllOUSly apprOlled testing and anal)'Sls

14 me11lod ,          for seismic end LOCA evenlS, the NRC 5Utff performed a graded review of the

15 .::E.             . lhat took into consideret1on lhe fact lhlll m05I aspects of ~
    16                 have already been addre5Sed as pan of prior NRC r9111ews The eppllcant

17 requesled approval -;                                     1              4 ,
    18
    19
    20
    21
    22
    23 I~26 The NRC staff examined tie prop068d approacn to produce Simulated EOL spacer gnds

....,...,.....,__~-+,--;ii;..~-N-4..___l!IMI~ and detem11ned tnet lhe simulated EOL

spacer grids would adequately aipb.tre the non-conservabve impacts due to irradiation The

0
    27  stlllf also detennined that the [

28
    29
    30
    31                             ~ The NRC staff's findings were based prtmanly on lhe specttlc matelial

32  type (zirconium alloy) and general grid design covered by the Information presented In lhe TR. [

I 33
    34
    35
    36  The use <:A flowing water Clamping ratios is not an entirely new approach to dMop more

realistic perameters that help mitigete the imped of vtbnltory loads. because ,t is similar to _
  IE40
                                                    * *            the NRC ..,_         -* the AP1000
                                  (Reference 1. '4) However. this 1s lhe first ~me 11111111 iS being appbed

more generically to 1/Yestlnghouse and CE luet. In parUcular. the applicant 1s propoSing the use

41  of a bounding curve 1111111s applicable to all spacer grtds uSed in Westingiouse and CE luel.

( 42  along with e general ~                         . that can be used to generate fuel design spea6c

43  curves The slaff reviewed lhe information submitted in the TR aloog will responses to

I 44  requests for 8ddolionat informauon. and detennoned lhat the                                was

46  appropriate for botl purposes. AdditJonally. lhe guidance provided for ublizallon of nowtng

46  water dampmg rabOi in seu;mic and LOCA analyses was found to be illppropnate for lhetr

I~
        Intended uw. with lhe 1.,Jmrtation

49
                             8FFleh..L l,IBE 814L'f       PR8PRl~M'f IPIF8RMM1814 PWROG-16043-N P-A                                                                                           November 2019 Revision 2

WESTI NGHOUSE NON-PROPRIETARY CLASS 3                                                                             A-41
                             8FFl8hlct. 118E 8Ht.Y     PR8PRIElAR'f INF8RMA'fl8N

- 16 -
       1
       2
      3
       4
      5
      6
      7
      8
       9
     10
     11                                                                                                    commented [114): Oetata this Nxt. plaase see the ta)IJ

12                                                                                                    onlot!orOG-1~13
     13  In summllfY. 1he NRC S111fllnas il'tatlhe 1h ormaffon pl'Ollfoed n me TR all(! responses to NRC

I 14  staff RAls adequately demonstrates that the proposed ~ 1 1 , j .

* to address EOl

15  effects on spacer grids and lo recover margin through credit for flowing water damping are

I 16  acceptable for use with existing method       *
* that the NRC has previousy found to be

17  acceptable for analysis of fuel assembly structural behavior ruling seismic and LOCA 8\181'11S.

I 18  The NRC staff approval of ........1.:i                  extends to all Westinghouse mid CE fuel

19  designs. contingent an adherence to the limitations and conditions set forth in Section 5.0.

20
     21  7.0      REFERENCES

22
     23  1. PWROGl...,.00.17-12, Jack S1nngr.tloo,, OliefOperalng OfficerandCllaiml.-i,
     24      PWROG. to USNRC dcx;ument contrtll desk. ra: *su1m111a1 of PWROG-16043-P. Rev191on

2!i     2. 'PWROO Progrwn to Ad<<ess NRC Information Notice 2012-09: '111'adia110n Effeds on

26      Fuel As!lembly Spacer Grid Cn.lSh Strength' fOr Wesllt ighollse and CE PWR F\Jel Designs

'Zl     PA-ASC-1169R2.-Feb11181Y 1, 2017 (AO,,MS AccesSlon NO ML1703980e0)
     28
     29  2. P'MOG-16043-P. Revision 2. "PWROG Program to Address NRC lnfamll1ion

30      Notice 2012-09. 'lrradlallon Effeds en Fuel Assembly Spac8' Grid Clush Snnglh' far

31      Wlllllns,iause and CE PWR Fuel Designs," Jaluary 2017 (ADAMS Package Acceaion

32      No. ML 1703SIB0S 1l

33
     34  3. PWROG letter QG.18-62, Jack S1nngfeHa.v. Ouef Openlllng Officer and Olatnnan,
     35                                                                      or

PV'JROG. to USNRC doa.ment contrtll desk. l'e'. *rramnuttal 1he Response II) Request

36      fer Addtional Information. RAIS 4 and 5Asaodaled with F'WROG-16043, RNl!lcri 2.

37       'PWROG Program to Address NRC infofma11an Nolice 2012-09: 'lrradi811on Effeclli on Fuel

38      Assembly Spacer Grid Crush stengt,' for Wednghou&e and CE PWR Fuel Desli,,s,'
     39      PA-ASC-1169.* March 27 2018 (ADAMS Accesaon No. ML 18100A053)
     40
     41  4. PWROG letter 00.18-104, Jeck Smngtellcw. Chief Operating Officer and Chelnnan.

42      PWROG, II) USNRC document c:onl'lll desk. re: *rranamillal or the Raapc:nse IO Request

43      fir A<dtional lnfonnatoo, RAIS 1, 2, and 3 Assodaled with PWROG-1eo43. Revision 2..

4-4     "PWROG Program 10 AddN!SS NRC lntonnaUcn Nollce 2012*09'. 'll'!Bdlaton Effecus on FUIII

45      Asambly SpaarGnd Oush Shngtl' farWe&1nghouse and CE PWR Fuel Desls,1$.'
     46      PA-ASC-1169," May 1S. 2018 (ADAMS Ac:ces&ion No. ML181438462)
     47
     48  5. PWROGleller QG.18-105. Jack Slnngfeloo,, OliefOperaling Officer and Challman.

49                                                                      or

F'W'tOG, IO USNRC doa.ment Conl'lll desk, re: *Transmittal the Respaise lO Request

8FF181AL 119E 8NLY        PR8PRIHM&#xa5; IPIF8RMM=l8PI

PWROG-16043-NP-A                                                                                                                   November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                       A-42
                                8FFl8htd.: t:18&#xa3; 8Nl::\f PR8PRI E:PAR>f tttF8RMA'fl8N

* 17
     ,       ror Addllcnal lnbmallon, FW 6 Aleocillted Witt PINROG-16043            RIMSOll 2, "PWROG

2       Prog!am lo Address NRC lnbmallon Nollce 2012-00 lrredldal Effects on Fuel Alilserub'(
             Sf*:8' Grid CNs1 strenglh for WednfloUse 1111d CE PWR Fuel Design& PA-ASC-1169
     .

3
     5 May 16 2018 (AOAMS ACIC8S5ion No ML ,a1~1eO)
     6  15, ~-9401-P-A, RevlllOn 0, "Veri1lcaioll T~ and Anl!ylla of lie 17),17 Op1lm1Zed F'l.lel

7       Anembly," Sep111mblf '1981 (ADAMS Aa:e55lon No hlLC80280486(~ubfldy

8       AvlilablelJ

9
   10
   11
   12
   13   8. NUREG-0800. "StMdlrd ReYlew Plan IOr tie Review ot 5fflly A n ~ tor Nudetr

1,        PClllltr Ptanlll. LWR Edl1k111," ChlpCer 4.2, RlM9lan 3. "Fual Syshlm OasiQn,' ~ 2007
   1!1       (ADAMS Accession NO Ml.070740002}
   18
   17   9. NRC lntt>lmdon NoCICe 20f.Z-Q9, ''11Tadta110n E"8c:15 on FUii AnlmlllV Spac;,ar Gncl CNlfl

18        SI~." dldal -'"1e 28 20t2 (ADAMS AoceNlon No Ml.113'70490)
   19
   20    10, NUREG-0800. "S1ancllrd R9Ylew Plan for lhe Rev,ew of Safety Anllly&lt,Raporta for NudN'
   21        Pow<<~ LWR Edition." &deg;'8pte,' 115 0.2. ~lion O "Re\,'lew d Transient and Aa:ldeftl

22        Mtll'iSIS llkllllo05. March 2007 (AO.AMS AOC855fon No ML070820123)
   23
   :z.t  , 1 NRC letW tern B11an Benr,ey. Senior Prqect Mllnllglr, Licensing~ lnndl,
   2&        [lvlllOII of Palc:y 11114 Rulemlllllng. USNRC. to Jack S111ngltlloW, Chief Openllng Ol'lleer

26        SIG OMumten. f'IIIIR)G, re:       *summe,y  Report for the OdoCler 17 2017 Aucltin 5'"art of

'l1       lhe Review of PWROG-160,43.P Revnilon 2 "PWROG Prav111m IO Addresi NRC

28        Jnfllnnlltion Noice 2012-09 *trradiallm effeds on F u e l ~ si,--a111 O\st

29        Slrengt,' for Wesln;houae Incl CE PWR Fuel Dells,,s. J1n11a1Y 8, 2018(Alli'MS

30        Acoeseion No ML 17328A,003}
   31
   32    12. Frwnatame NW, Ille. leller NRC-03:051 James F           Malley. ClitedCr. Regill8laly All'IWs

33        l'lwnUl!MANP, ~. toUSNRCdoolmen!OllirddQk. 111 -OOU.Of~
   3'        Repc,t~2. '5'*<< Gnd OWlh SlrenQtt - ElflldSOf IITaChllOft .* .August 8, 2003
   315       (AMMS ACICl!SllilCn No ..LG.12240428)
   36
   37    13. WCAP-17524-Pl'NP-A, Re\lltl<ln S, "AP1000Ccre Rer.-.nceRepclf.-Mtly2015(AOAMS

38        AconlltonNo Mll~1-.175)
   39
   40    14. Wesli~ouse letter Ll'R-NRC-13-26. Jemes A Quhman, Marllga', ReQiata,y

41        C\llnpliance. WallnghQuse Blldr1c:Cornpany 1D u ~ llocUm<<lt contol destc.

42        re **Sl4)plemenllll lnfom1e6an an Em:klf-Ufe S.anict'LOCA ~ for h AP1000
   43        PreS$Ur1Zed W..RNc:li:lr(Pl'Opriay~,* Aprll 30, 2013(ADAMS

44        Acoe5slon No ML 13121!.Ml7)
   ,45
   '6    111 Awnalome ll'lc rwpcrt ANP-10337P-A. R4Maon O 'PWR Fuel Asefnlbly SIIUdl.nl

47        Ra,pon11e lo Eldlernlly Applied ~ Ellcitdons." .Airll 2016 (ADAMS Padcage

48       Acce&llon No ML 181<<Aa18)
                                8FFl&ll.l 111E 8NLY      PR9PRIE'fAR&#xa5; INF9RM~8N

PWROG-16043-NP-A                                                                                           November 2019 Revision 2

WESTI NGHOUSE NON-PROPRIETARY CLASS 3          A-43
                                                     - T!l -
    1
    2 l'lirltipal Ccwllllblilor Scott Kll!pej NRRA:>SSISNPB

3 I tel9 August 22. 2018 eFFleli'cL 1,19[ 8NLV  P9'8PRIE'MRV INFSRMMleN

PWROG-16043-NP-A                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                 A-44 Program Management Office

1000 Westinghouse Drive, Suite 380
                                                                          Cranberry Township, PA 16066 PWROG-16043-P, Revision 2 Project Number 9990203 7 May 15, 2018 OG-18-105 U.S. Nuclear Regulatory Commission

Document Control Desk

11 555 Rockville Pike

Rockville, MD 20852 Subject:       PWR Owners Group

Transmittal of the Response to Request for Additional Information, R.\1 6 Associated with PWROG-16043, Revision 2, "PW ROG Program to Address

~RC Information Notice 2012-09: "Irradiation Effects on Fuel Asscmbh*
                       Spacer Grid Crush Strength" for Westinghouse and      c*~  PWR Fuel Designs",
                       PA-ASC-1169 References:
            I. Letter 00-17-12, Submittal of PWROG-16043-P. Revision 2, "PWROG Program to

Address NRC Information Notice 2012-09: "Irradiation Effects on Fuel Assembly Spacer

Grid Crush Strength"' for Westinghouse and C'E PWR Fuel Designs," PA-ASC-1 l69R2, dated February I, 2017
            2. NRC Letter of Acceptance for Review of PWROG-16043-P, Revision 2, "PWROG

Program to Address NRC Information Notice 2012-09: "Irradiation Effects on foel

Assembly Spacer Grid Crush Strength" for Westinghouse and CE PWR Fuel Designs."
               dated June 20. 2017
            3. Email from the NRC (Benney) to the PWROG (Holderbawn). Request for Additional

lnfonnation. RA!s J-6, RE: PWROG-16043-P. Revision 2, "PWROG Program to

Address NRC Information Notice 2012-09: **Irradiation E~is on fuel Assembly Spacer

Grid Crush Strength" for Westinghouse and CE PWR Fuel Designs." dated

January 31, 2018
            4. Letter OG-18-62, TrausmittaJ of the Response to Request for Additional Information, RA!s 4 and 5 Associated with PWROG-16043, Revision 2, "PWROG Program to

Address NRC Information Notice 2012-09: "Irradiation Effects on Fuel Assembly Spacer

Grid Crush Strength'" for Westinghouse and CE PWR Fuel Designs", PA-ASC-1169, dated March 27, 20 I 8 PWROG-16043-NP-A                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                   A-45 U.S. Nuclear Regulatory Commission                                                  May 15, 2018 OG-18-105                                                                             Page 2 of3
            5    Letter OG-18-104, Transmittal of the Response to Request for Additional Infonnatton, RAls 1, 2 and 3 Associated wrth PWROG-16043, Revision 2, "PWROG Program to

Address NRC Information Notice 2012-09: ''Irradiation Effects on Fuel Assembly Spacer

Grid Crush Strength" for Westinghouse and CE PWR Fuel Designs", PA-ASC-1169, dated May 15, 2018 On February 1, 2017, m accordance with the Nuclear Regulatory Commission (NRC) Topical

Report (TR) program for review and acceptance, the Pressurized Water Reactor Owners Group

(PWROG) requested formal NRC review and approval of PWR00-16043-P, Revision 2 for

referencing m regulatory actions (Reference 1). The NRC Staff has determmed that additional

mformatton is needed to complete the review per letter dated January 31, 2018 (Reference 3).

Enclosure 1 to this letter provides a response to NRC RAJ 6 (Reference 3) associated with

PWROG-16043-P, Revision 2, "PWROG Program to Address NRC Informatton Notice

2012-09 '"Irradiatton Effects on Fuel Assembly Spacer Gnd Crush Strength" for Westinghouse

and CE PWR Fuel Designs.

Responses to NRC RAis 4 and 5 were transmitted to the NRC via Reference 4 on March 27,
         2018. Reference 5 transmitted responses to NRC RAls 1, 2 and 3 to the NRC on May 15, 2018.

Also enclosed ts the Westinghouse Applicaiton for Withholding Propnetary Information from

Public Disclosure, CA W-18-4739, accompanymg Affidavit, Propnetary Information Notice, and

Copyright Notice.

As Item 1 contains information proprietary to Westinghouse Electric Company LLC

("Westinghouse"), it is supported by an Affidavit signed by Westinghouse, the owner of the

mformation The Affidavit sets forth the basts on which the mformation may be withheld from

pubhc disclosure by the Nuclear Regulatory Commission ("Commission~) and addresses with

spectficity the considerations listed in paragraph (b X 4) of Section 2.390 of the Co1Illillss1on's

regulations

Accordingly, it ts respectfully requested that the information winch is proprietary to

Westinghouse be withheld from public disclosure m accordance with 10 CFR Section 2.390 of

the Commission's regulations.

Correspondence with respect to the copynght or propnetary aspects of the item listed above or

the supporting Westinghouse Affidavrt should reference CAW-18-4739 and should be addressed

to James A Gresham, Manager, Regulatory Compliance, Westinghouse Electric Company, 1000
         Westinghouse Drive, Building 2 Suite 259, Cranberry Township, Pennsylvania 16066 PWROG-16043-N P-A                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           A-46 U.S. Nuclear Rcgulatocy Commission                                            May 15, 2018
        00-18-105                                                                        Page 3 of3 Correspondence relatod to this transmittal should be addressed to:
                              Mr. W. Anthony Nowinowski, Executive Director

PWR Owners Group, Program :Management Qffico

Westinghouse Electric Company

1000 Westinghouse Drive

Cranbcny Township, PA 16066 If you have any questions, please do not hesitate to contact me at (805) 545-4328 or

Mr. W. Anthony Nowinowski, Program Manager of the PWR Owners Group, Program

Management Office at (412) 374-6855.

Sincerely yours, Ken Schrader, COO & Chairman

PWR Owners Group

JKS:am

cc:    PWROG Analysis Conmrittce (Participants of PA-ASC-1169)
               PWROGPMO

PWROG Steering and Management Committee

J. Andrachek, Westinghouse

K. Lasswell, Westinghouse

J. Sinegar, Westinghouse

B. Benney, US NRC

Enclosure 1:   PE-18-25-P/NP, Attachment l, "Response to PWROG Topical Report PWROG-
                       16043-P RAI 6" (PA-ASC-1169)
        Enclosure 2:   Affidavit for Withholding, CA W-18-4739 (Non-Proprietary) with accompanying

Affidavit, Proprietary Information Notice :md Copyright Notice

PWROG-16043-NP-A                                                                                November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                        A-47 Wcstinghouso Non-Propriclmy Cla5s-3
     @westinghoi.Jsil

From;         Roge*r Yong LtJ                                                            Memo: 'P.E~1Ba25:-NP Rev. 1 Pt,on_e:         (803)' 647-3426                                                              Date: M~ 9, 2018 a-mall:         lur@westjnghouse,com

Sllbject: -Response to PWROG Topical Report PWROG-16043-P R,AI 6 To: James P_ Mofkanthln                         JIii G. Sinegar           .James D. Andracnek

cc: PWRQG,
        Attached is the resPPIJSe to,RAL6*related_to the P\I\IROG Topfcal Report PWR0$-16043-P:
         Proprietary in(qrmation is si'!OWn'IJi b~~..~~_orcomments st,ould be_dl~*19 the

und~igned.

Autnor:                  Roger y_ Lu*
                                 !?WR, Fuel Technology, Vernier.                Jane-X. jjang"f

lheonaf-Hydratlli9 and Seismic Engineertng

'Verifier:.               Jrwei Wang*t

~*FueJT~
        Approver.                Kevin T .. lasswelr., Manager*
                                ThennaH;lydraullc anti Seismic~~-
         * [l}i:J,tr<Juicall), "!lllfOval n:<:Ofil&#xa5; l i e ~ lu ih'-' ckc~*di!euruciil ~,.:,,Ao!ll

\ Tht.ox J>a..s>Vuif."11.Srttin\ QPY;) 'l'tl'.li ~ \i:, \cru),* tin~ J.J~Um<.~Ao &in.~ w*!hc: ~ I.lu/:um6rt Vcrilfuilluu'Cb.i:l:l\il*y,ajcli,
      ** is ,,twcl,ed lo thia d,c,cum,:nt in PRTh,n;::.

PWROG-16043-NP-A                                                                                                                       November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                                        A-48 Westmghoosc: Non-Proprietary Class 3 PE-18-25-NP Rev

I, Attachment I

May 9, 2018 Page I of7 A new methodology Is being proposed for \/Vestinghouse and CE fuel to credit flowing water darr4Jing

m mibgatlon of the degradation In fuel mechanic behavior due to EOL effects on the spacer grids.

ThlS methodology is proposed as an option for use In lleu of the stJII water dalll)lng credited in the

prevlously approved methodologies. In order to fuly understand how the proposed methodology Is

Intended to conservatively capture the impact of flowing water on fuel assembly vibrations, the NRC

staff requests the following lnfor~tion:
       RAI Item 6 Section 4.6 of the LTR [

l a,c

Response to 6a

The fuel assembly damping ratio Is the measurement of energy dissipation In a

mechanical system. To 'account for the energy dissipation dunng vibration, the averaged

or best estimated damping ratio value 1s more appropriate to a full core fuel asserrbly

analysis from a physical standpoint This is different from other local bounding analyses, such as a Departure from*Nucleate Boa1ng (DNB) correlation.

Fuel Assembly (for the AP100o Plant) Flowing Water Damping Background

C E ~ ad APIOQCI arc hdcm.-b o:r rlfland tn.dmlwb of W ~ I C I Kloctnc ComplDy !LC, Iii afflklf:CII mdoc 1.11 mbaci.mti1 in tltc Ummd Sbtc1      ~ Amcoc1 ID<l ,my bo r,gill<nd tn < t i t e r ~ tbroapout Ille ..ortd All nahll ,_,.,.d Unm!ioruod . . lo *1diy ?"oiMixtod. otl>er...,.. may bo

tndc:macb of ai:w r-..;i,ccti** OWD1n.

-Th11 record wa9 flnal approved ai 5/10l2018 4 07 37 PM (Th* statement wa9 eddod b'f lhe PRIME oystem ~on its valldllbal)
PWROG-16043-NP-A                                                                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                       A-49 Westrnghouse Non-PrOJnetBiy Class 3 PE-18-25-NP Rev

1, Attachment 1 May 9, 2018 Page 2of7
                 1a.c

a,   C

Figure 1 : Dampmg vs. Velocrty Curve ~t was used for [

] a. 0 Model (Reference 1)
         - nu,, record was flnal approved on 5110/2018 4 07 37 PM (Th'" otatement was added by the PRII.E system upon rts valtdallon)
PWROG-16043-NP-A                                                                                                                November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                      A-50
                                                 Westmghousc Non-Pro&#xb5;-wtary Class 3 PE-I 8-25-NP Rev

I, Attachment I

May 9, 2018 Flowing Water Damping Curve for PWR00-16043.P

] a, e

,C

Figure 2. Damping vs Velocity Curve for [                           ] a, 0
         -This record wu flnol appr0\/8d a, 5/10/2018 4 07 37 PM (Thl5 5!a!ement was added by the PRIME 5Y5lem upm rt* Vllbdaba,)
PWROG-16043-NP-A                                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                        A-51 Westmghousc Non-Pro~etary Class 3 PE-18-25-NP Rev

1, Attachment 1
                                                                                                              :May 9, 2018 Page 4 of7 Response to 6b

The fuel assembly damping force In flowing water is the surrrna.tJon of the fuel structural

dal11)ing in air, viscous damping in still water and the hydraulic damping In flowing water

as shown in Equation (1) The flow,ng water damping coefflC1ent measured and used 1n

PWROG-16043-P is also the summation of these three components

(1)
             c. - The structural damping coefficient In air, due to            material and friction damping.

c.,- The viscous damping coefficient In stJII water

ch - The hydraulic damping coeffie1ent in flowmg water, -which primarily Increases wrth

the axlal flow velocity

All three damping coefficients In EquatJon (1) are neither constant nor linear. All tests

that were performed by other fuel vendors concluded that the water temperature has a

small effect on fuel assembly damping. Babcock & \Nilcox's paper (Reference 2)
            concluded that darfl)ing is mm!mally affected by teITl)erature ranges from 68<>F to 60C)oF.

The Mitsubishi Heavy Industries' topical report (Reference 3) concluded "that the

temperature effect of AFD (Axial Flow Damping) appears to be very small up to the

reactor operating condition from the maxnn1m test temperature." The flowing water

damping tests performed by V\/estlnghouse are consistent With this conclusion

Test data trend curve fitting

l &, C

1) [

l &, C

-Thll record WU tnaJ approved on 5110/2018 4 07 37 PM (This Wl!ement W81 added by the PRIME sy11tem 14JOll rt9 valldat!on)
PWROG-16043-NP-A                                                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                       A-52 Westrnghousc Non-Proinotary Class 3 PE-18-25-NP Rev

I, Attaclnient I

:May 9, 2018 Page 5 of?

,c

Figure 3* Damping vs Densrty at [                     Ja. 0 (Figure 4-14 of PVVROG-16043-P)
              2) [

l a, C

Table 1
* The average damping ratios at different temperatures at [                            ] a. 0
                                                                                                                                    a, C

3) [

l a, C

A discussion of the conservatism In the 600"F damping curve

l a, C

- Th11 record wu lnal approved ai 5110/2018 4 07 37 PM (Thio statement wa* ltdded by the PRIME syotem upon Its vahdallai)
PWROG-16043-NP-A                                                                                                                November 2019 Revision 2

VVESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                    A-53 Westmghouse Non-PrOJX161mY Class 3 PE-18-25-NP Rev

I, Attaclni ent I

:May 9, 2018 Page 6of7 a,  C

Figure 4* Damping Ratio vs. Coastdo'Ml Time

for a Typical v\lest1nghouse 3-Loop Unit (Figure 4-21 of P\/\IROG-16043-P)
       Summary and Conclusions

-This record was flnal approved on 5110/2018 4 07 37 PM (Tiu 9lalement wu added by the PRII\E system upon rts \lllbdabon)
PWROG-16043-NP-A                                                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                         A-54 Westmghousc Non-Propnetmy Class 3 PE-18-25-NP Rev

I, Attachment I

May 9, 2018 References

1. [

] a, e

2.  F. E Stokes and R. A King,-~ Fuel Asserrbly Dynarnc Characteristics,"
                International Conference on Vibration in Nuclear Power Plants, Keswick, United

Kingdom, May 9-12, 1978 (BNES), Page 31.

3. MUAP-13020-NP (RO), "Axial Flow Damping Test of the Full Scale US-APVIIR Fuel

Assembly," August 2013, Page 3-2.

4. 'v\CAP-9401-P-A, "Venflcatlon Testing and Analyses of the 17 x 17 Optimized Fuel

Asserrbly," August 1981.

-nu, record wu flnal approved ai 5110/2018 4 07 37 PM    (Tin statement was added b'/ the PRIME system upa, ~* vahda!Jai)
PWROG-16043-NP-A                                                                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           A-55 PiMll-25,Np ''"">n-1
                     -- - -  -.-                          --         -
                                                                                            ;
                                                                                                --
                                                                                                  --     '
                                                *.AP.Pft~~~:lralofrr)l_a~101'          -
                                                   - .

'
                                                             -       -
                                                                      - . - --     . - -- -
                                     />:uttwr. Approval Lu 'Roger May,,1 Q-2018 10:41 :07
                                 --                                                           -
                                    Verifier. App.n;>val W~ng Jlwer May-10-201 ~i.1~:9,0:s*1
                                          -                                     -
                                    VenlierApprovaJ Jiang Ja_ne May-10-~1811,:56:12
                                                     -
                            'Manager Approval Lass~H Kevin t ~~y-f6:-2Q1&1~:P7:37 PWROG-16043-NP-A                                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                       A-56 Prognim Management Office

1000 WM1)nghouse ~\.'.fl, Surte 380
                                                                                'Cranoerry Township, PA 16086
                                                                              *~WROG-16043-P, Revision i

Pr<:Jject Nu&#xa2;ier 999020-3 7 May ts, 201&
        .dG-18-104 US Nuclear Regulatory Comm~ion

Document Control'.Desl5.

t t555 Rockville Pike

Rockville.. MD Z085Z

Subject:        PW,R owners Group

Tnmmittal of'the Response,to'Reguest for-Adclitional'Information, lt\ls f,
                         2  aad.JAsw;iated with rWR00-16043, Revisiop 2,-".PWROG Program to

Addrgs''NRC Information Notice 2012--09; ")rnailiation Eff<<u OD Fud

Assembly Spacer Grid Crwh Strength~ for We.,tinghome and CE,,PWR Fuet

Designs",.PA-ASC-116~                -         ,                                -
        ~eferences:
             L    Leyter OG-17-12, Submittal -0.f' PWROG-16043-P, Revision 2, -PWRO<tfrogram to

Address NRC Tilfortnat.io!l Notice 2012-09: "Irradiation Effects 011 Fucl,A!Jsembly Spacer

Grid Crush Strength'' f9rWcstinghousc and CE PWR Fuel Designs." PA-ASC-l 169R2, dataj F~bruary-1,-2017               -
             2. NRG Letter      of .(\cceptimce for Re~ ,of,PWROG-1@43-P, 'Revision ?, "PWRO'G

Program to Address "t-/RC I!lformatiov. Notice .2012-09: "'Irtadia1;ion Effects oil Fuel

Assembly Spacer Griq Crush StrengtJi'' for Westinghouse and Cl:. PW~ f'.ticl :Qogigns;''
                  ~June 20. 2017                     *                                                       *
             3'.- Email frolT! the NRC' (Benney) ~o the PWJWG' (Hol~aum), ~equest for AdditjonaJ.

lnfonnation, IV,:ls *1-6, RE: PWROG:(.~3-P,, Revision *2, *'PWROG Program tb

Address NRC lnfunnation Notice 2012-09: '7lrrndiation Effects on Fuel Assembly'Spacer

Grid Crusli_ Strength" for W~ingh_ouse -l!Il-~' CE&deg; 'PWR F~el Designs," !lated

January 31, 201 ?'
             4. ~ r OG-18-62, Transmittal of the Response; to Request f91' Additional Information, RAls ,4 and 5 Associated witn PWROG-16043. Revision Z, *'PWR.OG 'Program to

Address NRC Jpf~ation *Notice i012-QQ: ''irradiation Effecl5 on Fuel Assembly Spacer *
                  Grld' Crush ~~gth' 1 for 'W~tin'gh_ouse and CE PWR, fuel Desiwis". PA-ASC-1169, d!lfed_Mftrch_27. 7018 PWROG-16043-NP-A                                                                                               November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                               A-57 U S. Nuclear Regulatory Comrmssion                                                 May 15, 2018
         00-18-104                                                                            Page 2 of3
             5. Letter Chl-18-105, Transmittal of the Response to Request for Additional lnformatJ.on, RAI 6 Associated wrth PWROG-16043, Revision 2, "PWROO Program to Address NRC

Information Notice 2012-09* "Irradiation Effects on Fuel Assembly Spacer Grid Crush

Strength" for Westinghouse and CE PWR Fuel Designs", PA-ASC-1169, dated May

15,2018 On February 1, 2017, in accordance with the Nuclear Regulatory Commission (NRC) Topical

Report (TR) program for review and acceptance, the Pressurized Water Reactor Owners Group

(PWROG) requested formal NRC review and approval of PWR00-16043-P, Revision 2 for

referencmg in regulatory actions (Reference 1). The NRC Staff has determined that additional

information is needed to complete the review per letter dated January 31, 2018 (Reference 3).

Enclosure 1 to this letter provides a response to NRC RA1s 1, 2 and 3 (Reference 3) associated

with PWROG-16043-P, Revision 2, "PWROG Program to Address NRC Information Notice

2012-09: "IrradiatJ.on Effects on Fuel Assembly Spacer Grid Crush Strength" for Westmghouse

and CE PWR Fuel Designs.

Responses to NRC RA1s 4 and 5 were transmitted to the NRC via Reference 4 on

March 27, 2018 A response to NRC RAI 6 was transmitted to the NRC via Reference 5 on

May 15, 2018.

Also enclosed is the Westinghouse Apphcation for Withholdmg Propnetary Information from

Public Disclosure, CAW-18-4738, accompanying Affidavrt, Propnetary Information Notice, and

Copyright Notice.

As Item 1 contains information propnetary to Westinghouse Electric Company LLC

("Westinghouse"), it is supported by an Affidavit signed by Westinghouse, the owner of the

mformation The Affidavit sets forth the basis on which the mformation may be withheld from

pubhc disclosure by the Nuclear Regulatory Commission (''Commission") and addresses with

specificity the considerations listed in paragraph (b X 4) of Section 2 390 of the Comm1ss10n's

regulations.

Accordingly, it IS respectfully requested that the information which is proprietary to

Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2 390 of

the Commission's regulations.

Correspondence wrth respect to the copyright or proprietary aspects of the rtem listed above or

the supporting Westmghouse Affidavit should reference CAW-18-4738 and should be addressed

to James A Gresham, Manager, Regulatory Comphance, Westinghouse Electric Company, 1000
         Westinghouse Drive, Building 2 Suite 259, Cranberry Township, Pennsylvania 16066.

PWROG-16043-NP-A                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                           A-58 U.S. Nuclear Regulatory Commission                                            May 15, 2018 OG-18-104                                                                        Page 3 of3 Correspondence related to this transmittal should be addressed to:
                              Mr. W. Anthony Nowinowski, Executive Director

PWR OWners Group, Program Management Office

Westinghouse Electric Company

1000 Westinghouso Drive

Cranberry Township, PA 16066 If you havo any questions, please do not hesitate to contact me at (805) 545-4328 or

Mr. W. Anthony Nowinowski, Program Manager of the PWR Owners Group, Program

Management Office at (412) 374-6855.

Sincerely yours,
         )Lj~
        Ken Schrader, COO & Chairman

PWR Owners Group

JKS:am

cc:    PWROG Analysis Committee (Participants of PA-ASC-1169)
               PWROGPMO

PWROO Steering and ~Ianagement Committee

J. Andrachek, Westinghouse

K. Lasswell, Westinghouse

J. Sinegar, Westinghouse

B. Benney, US NRC

Enclosure 1.   PE-18-34-PINP, Attachment l, "RAis I, 2 and 3 Responses for PWROG-16043 Revision 2" (PA-ASC-1169)
        Enclosure 2:   Affidavit for Withholding, CA W-18-4738 (Non-Proprietary) with accompanying

Affidavit, Proprietary Information Notice and Copyright Notice

PWROG-16043-N P-A                                                                               November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                   A-59 from,: Jane Xlaoyan Jlang                                                   Memo: PE-18-34-NP

*Phone; (803) 647e3735*                                                         i::ate: May a. 2oia

e-maD; jjangx~nghouse com:
              To; Jill G. Sinegars                                          JafT!es-P. MoUcenlhin*
               CC,   PIJ'IR0G

1 Attacl1ecl a*fE! the resporises to R,?-ls 1. 2. and:3 rela~_ to the P\r'fROG fopicarReport PVYROG-
      *i6043-P. Proprietary [nformatlon ls s.hoWn fn braokets. Questions orcomrnents'6li04.lld be-directed to

*the unoerslgned1 *                 *                                                                 *
        Author.         Jane.X.-*Jlang *
                        T~ei:n,af-Hydi:aulic' ar,id Sefsm\Q.E(lglneering

VerlflElr:      Rpg~ Y.. Lu   "&deg;t

PINR Fuel Techn(?iogy

.K~ln T, l:.a~I, ~a~gee              _
                        Theim~l-l;lydr:aul!Q and ~ic,Enginee(ing

-.

t ~.Pusa Verifi<;tti~ (3J'V),,'11:11 llll*idto'~fy Un~ UQCIJU!enf,..-<lemon~lmtlld in the.-~ Docurmmt.

-v~~ ~ whi~ ii> ettachcd 't(} fuia docl.uneoj;'ln PRIME,,
PWROG-16043-NP-A                                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                             A-60
                                                            Westmghouse Non--Propnetary Class 3 PE-18-34-NP,
                                                                                                                    Attachment 1 May 8, 2018 RAI 1 The most significant aspect of the proposed methodology to address EOL effects on

the spacer grids is the use of simulated EOL grids, which ere grids that have been [I

0
                                              ] ] "'    to simulate the most important non-conservative EOL effect

due to 1rradiat1on, grid spring relaxation. In order for the simulated EOL grids to

accurately capture the hmrting behav10r of irradiated grids, the structural charactenstics

of the simulated EOL grids must be similar to, or more conservative than, the irradiated

gnds In order to venfy this, the NRC staff requests the following information

The [I                                     ]] "' 0 protocol is not detallad in the LTR. In Section 2.1, the

LTR states that the "process for compiling PIE data and specrfymg target cell size is

consistent with that was used for the AP1000 EOL 1SSues that was previously approved

by the NRC

* However, the exact [[                                                        ]] "' 0 protocol Is unclear

Please proVJde the specifications for the [I                                                ]] "' 0 process, including

[I                                                                  ]]"'c

Response to RAJ 1 The [                                     ] "' 0 of the simulated End of Life (EOL) gnds for the

AP1ooo<<> plant and the simulated EOL gnds discussed m PVVROG-16043-P was

performed m accordance with a Westinghouse thermal cell sizing procedure.

The procedure 1s used to thermally size grid cells to simulate EOL grid

conditions for fuel assembly hydrauhc loop tests

0
                                                     ] "'  
* The process is shown in Figure 1. [

The mechanical structure charactenstics of simulated EOL grids is similar to, or

more conservative than, the irradiated grids. [

0
                                                                                             ] "'      Therefore, the grid material

characteristics of Young's modulus and Poisson's ratio are not Impacted by the

gnd [                                     ] ., 0 process The Young's modulus is one of main

parameters which determine the grid Impact stiffness.

AP! 000, 2JRLO and Optuntud Z!RLO aro trulc:omb or rogistercd tradcmarts of WOltinghouoc Ela:tnc Company LLC, Ill lffiltalc!! an<Voc Ill

!llb!lidanco Ul the UJU:cd Slaw of America and mo:y be regtJtacd mother countnco throughout tbc wcrld All ngbts nocrvcd Ummthonzcd nsc JJ

,tnctly prolwJ!cd Other 01D1C1 may be tradtmarb of thc!r rc:opcctrvc owncro

-   This recad was ~nal apprt>Jed oo 5/14/2018 10 48 53 AM (This statement was added by the PRIME symem upon 11s V!Udat!on)
PWROG-16043-NP-A                                                                                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                          A-61 WestmghoWIO Non-Propnctruy Class 3 PE-18-34-NP,
                                                                                                                  Attachm cnt 1 May 8, 2018 Page 2 of JI

a,c

] 0.

Figure 1. [                                                C

Smee the [

0
                                          ] a,     This may result In a slight reduction m the grid impact

strength, which 1s conservative.

The [                          ] .. 0 target cea sizes or gap sizes are varied depending on

the Post Irradiation Examination (P1E) data and types of grid designs. [

1. [                                                              .] .. C

2    [

overall, the [                                       ] a. 0 for cell sizes wlll have no impact or a

minimally conservative impact on the gnd strap material mechanical properties

-Tots recad was Ina! oppro>Jed on 5/1"'2018 10 48 53 /J,N, (Th111 statement wu added by the PRIME oyotem upon !Is VMclllhon)
PWROG-16043-N P-A                                                                                                              November 2019 Rev1s1on 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                      A-62 Westmghoose Non-Propnetary ClllSll 3 PE-18-34-NP,
                                                                                                                  Attachment I

May 8, 2018 RAJ 2 Fuel assemblies that are loaded in certain areas of the core may expenence steep

radial neutron flux gradients. As such, the EOL effects due to irradiation of the spacer

grids may not be sufficiently uniform to result In spacer grid behavior consistent with

simulated EOL grids using the [                                      ]] ., 0 method. Please characterize

the expected variation due to radlal neutron flux gradients in typical PWR cores, and

discuss how this may impact the spacer grid structural behavior (e g., if gaps exist at

one corner of a fuel assembly but not at the opposite comer, explain what the effect on

the failure mechanism might be).

Response to RAI 2 a. "expected variation due to radial neutron flux gradients in typical PWR cores"
                        The fuel rods In a fuel assembly may experience steep radial neutron flux

gradients in some core locations during some cycles. However, the grid gap

size formation (due to gnd spring relaxation, rod diameter creep and grid

growth) is a long-term and ~low process which occurs over the entire irradiated

D1'e of a fuel assembly

The typical Irradiated lifetime of a fuel assembly is at least 4 years dunng which

it will be rotated to dlferent locations 1n the core and experience different flux

gradients and onentatJons. Therefore, a radlal neutron flux gradient effect on

the gnd cell size at the fuel assembly EOL condlt10n Is not expected to occur.

To confll'm that the neuron flux gradient effect does not occur, two sets of PIE

data, fuel rod burnup vs eel gap size, were reviewed Fuel rod bumup at EOL

Is the accumulated effect of neutron flux. [

]. a, e

The first example is a [                                         ] ., 0 for which the measured gap

results and corresponding fuel rod bumups are given in Figure 2 A sample of

ten fuel rods in different locations in the fuel assembly with different fuel rod

bumups Is shown In Figure 2 [

Figure 2 also shows that [

.] a. e

- Ttus record wa5 flnal appro,ed on 5114/2018 10 48 53 AM (Tin ,rtatement W85 added by the PR IME system upoo rts VMda!Jon)
PWROG-16043-NP-A                                                                                                              November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                         A-63 Westmghouse Non-Propnetary Cl~ 3 PE-18-34-NP,
                                                                                                                 Attachment I

May 8, 2018 a,c

] a, Figure 2. Measured [                                                                   C

The second example 1s for a [                                                   ] a. 0 The measured

gap results and corresponding fuel rod bumups are given in Flgure 3. A sample

of ten fuel rods in cfrfferent locations in the fuel assembly with different fuel rod

bumups Is shown In Figure 3. [

- This record wu flnal approved on 5114/2018 10 48 53 AM (Th,o .taternent was added by the PRIME oystem upon 119 va~datton)
PWROG-16043-N P-A                                                                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                       A-64 Westmghousc Non-Propnotary Class 3 PE-18-34-NP,
                                                                                                          Attachment I

May 8, 2018 Pago 5 of 11 Figure 3 also shows that [

10, C

a,c

Figure 3. Measured [

- This recad wu tnll approwd on 5114/2018 10 48 53 AM (Ttn statement WM added by the PRIME system upoo Its va!JdatJon)
PWROG-16043-NP-A                                                                                                        November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                     A-65 Westinghouse Non,Propn.miry Class*.?..

PE'- l 8-3+-N;r>,
                                                                                                             :Attachment I

May~, go13
                                                                                                             ~6ofll,
                                             .J ...

b.    "how this may impact tfie* BJ>Bc.E:r grid $uctur,al behavjor"
                  The grid Im~~ ~urs OI') the grtd side surfaces F9r ex~l)"lpJe, !!> .grid *l:l

lmpact~d n the X dl~n as shown In Ftgu~ 4, The lmpact'for~ ~* 3:hared by

.the whole column A (~m ~II A1 ~ cell A 17)_ and ll? tra~fe~ to the wrn;ile grlg.

tflrough all' po!Um~ (from Column A to Column 9), Tt~refore, ths ceU i&#xb5;ip s~
                  differences in a gri~ would have a small Impact on *the overall ~ a l l?e~vior

i;>f ~ ;,pacer grid.

A   Ill  ( ' I,   -   j, '* 6, *l P

* J . ~ Ji , j, ,. I [I p fi ,
                                  *l

l--+--+--+-+-+--+--+--+--+--+--+--+---+---+--+---+'--1
                                     1 l---+--+--+-+-+--+--+--+--+--+--+---+--+--+---1---1---l

*} l---+--+--+-+-+--+--+--+--+--+--+---+--+--+-+---1---l

J

l---+--+--+-+-+--+--+---t--+--+--+---t---+--+-+-+---1
                                 *6 t--t--+--+-+-+--+--+--+--+--+--+--+---+---+--+--<---t

1 - .

-*->         ' ~* 1---r--+--+-+-+--+--+---+.--+--+--+---+--+--+---l---l---l

*~t--t---l'"---t--+-+--+--+---t--+--;---t---t---t'--+---1--'I---I

X direbti6n       .!!1,__+--+--+-+-+--+--+--+--+--+--+--+---+---+-+--+-<
                                     H1--+a--+--+-+-+--+--+--+--+--+--+---+--+--+--+---+----'I

~l---+--+--+-+-+--+--+--+--+--+--+---+--+--+---1---1---l

*~l---+--+--+-+-+--+--+--+--+--+--+---+--+--+---1---1---l

1"1---+--+--+-+-+--+---+---+--+--+--+---+--+--+--t---l---l

**. 1~ t--t--+---t--+-+--+--+---t--+--;---+--+--+--+-+---+---1
                                 ' I~ t--t--+--+-+-+--+--+--+--+--+---+--+---+--+-+---+---l

-.!1~~-+--~~~~~~~~~--+-~--+--+~
                                                    ~ure 4. Example of Grid Impact

i:he [                              J4. e ceU:gaps for simtllating-ttte E6t. .grids are also va~d

across-. grid locations..- The pre~ cells, realisti~lly ,represe'nt *the *mea;sured

ceu    gap characteristics, mim* the PIE *cjata. sucti as random ,disfrlbution, _-ga'p, ~~
                  rartg!3 1 etc, {                            *                                         . Ju

PWROG-16043-NP-A                                                                                                           November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                        A-66 Westmghouse Non-Propnotary Class 3 PE-18-34-NP,
                                                                                                               Attachment I

May 8, 2018 Pago7ofll

,] .. C

a,c

Figure 6. Measured [

.] .. C

- Th!s record was lnol approved on 5/14/2018 10 4a 53 AM (Th!S statement was added by the PRIME oystem upon ils validation)
PWROG-16043-NP-A                                                                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                   A-67 Westmghousc Non-Propnetary CIIIS5 3 PE-18-34-NP,
                                                                                                             Attachment I

May 8, 2018 Overall, the gnd impact between two fuel assembbes and a fuel assembly to a

baffle plate occur on the side surface of the gnd. The Impact surface transfers

the Impact force through all the grid straps (which are parallel and perpendicular

to the Impact direction) The average gap size in each column and each row for

a simulated EOL grid Is slmllar. Therefore, [

.j a. e

RAl3 SectJon 2.1 of the L TR presents PIE data from selected fuel assemblies and an analysis

approach that can be used to determrne a target average cell size for the SJmulated

EOL spacer gnds. This approach 1s intended for use with any fuel assembly des1gn, but

no specific guidance Is provided on how the PIE data set should be characterized for a

given fuel assembly design. Please provide guidance on the expectations for what

would constitute an acceptably robust set of PIE data for the purpose of establ1shlng a

bounding target average cell size for all fuel assemblies of the specified design type.

Response    to RAI 3 The grid target cell size Is determined based on the PIE data using a statistical

method. For example, the grid target cell size for [                                           ] a. 0 fuel

assembly 1s determined by the following steps:
                                    .] a. e

2    Calculate the upper 95% confidence limit for the true mean in order to

account for the scatter in the database. The upper 95% confidence limit 1s

calculated based on the statistical formula given below

"dG                  . _y, rl      STD X Tn-1 Mi     ricfw.,. 95 =Mi(,AJn~        + ..[ii

Where*
                                MidGridupp..ae -      Upper 95 confidence mean of the grid cell gap size from the

PIE data

M1dGrld..,g      - - Average grid can gap size from the PIE data

STD              -    Standard deviation of the grid cell gap size from the Pl E data

T              -     Student T value determined by the sample size

- Thts recad WM lnal approwd on 5/14/2018 10 48 53 AM (This statement W89 edded by the PRIME system upoo 115 vahdahon)
PWROG-16043-NP-A                                                                                                          November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                         A-68 Wcsungho= Non-Propnetary Class 3 PE-18-34-NP,
                                                                                                              Attachment 1 May 8, 2018 N                  -     Sample size

n-1               - - Sample size minus one

l'  C

3. [

.] 'C

a,c

Figure 6. [

] 'C

- Tots recad was ~nal approved on 5/1 "'2018 1 0 48 53 AM (nus otatemeni wu edded by the PRIME sy5tem upon Ila valtda!IO!l)
PWROG-16043-NP-A                                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                   A-69 Westmghouse Non-Propnctary Class 3 PE-18-34-NP,
                                                                                                             Attaclnn ent I

May 8, 2018 To ensure that the simulated EOL grids meet the target cell gap value, the

average cell gaps should be higher than the target cell gap value. For an

additional conservatism, the lower 95% confidence limit on the true mean of

tested grid cell gaps was confirmed to be higher than the target value. The

simulated average and lower 95% ceD gaps for a [

.] "'e

In general, the effect of the sample size Is incorporated into the statistical

method through the "Student T" value in the formula above. Smaller sample

sizes will have a larger Student T value. For example, [

.] 'e

Table 2. Example of the Gap Size Target Value Utilizing

a,c

. -nus record was flnel apprCM>d on ~4/'201810 48 53 AM (This statement Wa9 added by the PRIME system upa, ts vahdallon)
PWROG-16043-NP-A                                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                    A-70
                                                                                                               PE-18-34-NP,
                                                                                                               Attachm e.nt I

May 8, 2018 a,c

Figure 7. Sample [                                                           ] II, C

Based on the discussions above, [

1  II,  C

Is s ufflc lent.

References:
          1. [

.] II, C

- n u recad was tnal approved on 5n4/201810 48 53 AM (Thi$ otatement wa5 added by the PRIME oystem upon u va~dehon)
PWROG-16043-N P-A                                                                                                           November 2019 Revision 2

_ WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                        A-72 PWROG- f60,4J.p, Revision' 2

* Prop;t"'Nfuubcr 99902037 March 27, 2018
           00-18:-62 U.S. Nuclcar~atory CQfllIUission'
          lloi:uoiertt Control Ot=dt

11555 Rockville Pike

rteckvi11e. MD 20852 Subject:        PWR._ Owners Group- Tgpgdttsl of t!Jt,Rpppme to Rm&#xa2;st b Additjogl .lpi,rmtjop, RA1s :f

Hd S: MHPIIM wtt1 PWR00:16ff.J, Rcyilipg l, ..PW.ROG fremm to

A,ddtm, .N.RC    Jpfonpatf!! Npdce 1012-02; :t,rradlaftos        Effgt;. tn1 *fflCI

Apetgbff SP!ffl' Grid Cna H4mrtft" Jur:     w ~ agd ct PWR f.d

Dtsisps", t&ASC-U@                 -      *
          'RefefflKleS;
                I. Letter OG-17-12, SUbroittal of PWROG-16043-P, Revision 2. ..PWROG. Program to

Addrca NR.C Infonnatioo Notice 2011-09: ~~ &#xa3;ffuc!s on Fucl Assembly Spacer

Grid Cru,h Strangth" for Westinghouse and CE PWR F ltCI Dc!iigns... f A-ASC.;l I69R2, dated Febniary .I, 2017
               2. NRC l.cttcr of Aoccptn.occ for Review of PWROG-16043-P, Revwon 2. "PWROO

Program I.ti Addr,,ss NRC lnfonnatio,, Notice. 20l2.:o9: 1 ~ liili:ct.s Qn Fuel

Assembly spacer Grid Crush Strength'" ror Wcstingb!ll.lSe' ern1 c~ PWR rucl      r)c9;igttS,..

dared Jtme20, lO 11
               3. l2mail &om lhc NRC (Bei;iney} t0 the PWROCl: (Holdttbauin). Request fut Ad<litiooaJ

lnfonnatlon. Mis 1-6. tu::. PWR00-16043-P. R.evi&ion 2. "'PWROG Progt8lll tci

Addre5s NRC lnform.ttfoo Notice 201~ "lmul~F.ffects oo Puel. ~ Spacer

~ CNSh !>'trcngth: 1br Wtsting~ end~ fWR rucl Dcsigns." dated .Jaimaey'
                   31,1018
           0a _Febnwy l, 2017, in IICCOrdiJru:e wi1b th~ Nucleet Reguhltary COJIIIJ'lUi'Sion (NRC) Topical

Repo:rt (tR) p(OgBID tbr review l&#xa5;ld ~ c c , 1;tl&P~ Water &actor Owners Group

(PWRO(i, ~ foona{ NRC: review Mid approval of P\\IRCX.i-16043-r, Revl$ion 2 ~OT

referencing 1n rcgu]atory actioc)s (llcfetcbCC I). The NRC SlllJfbss determined lhai addltiOfUII

iu1bn.a1ioo i s ~ to compJete ~~*per letter-dated J ~ 31, 2018 (Re~ 3).

PWROG-16043-NP-A                                                                                               November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                A-73 U.S. Nuclear Regulatory Commission                                              tvlarch 27, 2018 OCH8-62                                                                              Pago 2 of3 Enclosure 1 to this letter provides a response to NRC RAis 4 and 5 (Reference 3) associated with

PWROG-16043-P, Revision 2, "PWROG Program to Address NRC Information Notice

2012-09: "Irradiation Effects on Fuel Assembly Spacer Grid Crush Strength" for Westinghouse

and CE PWR Fuel Designs,"
        Also enclosed are the Westinghouse Application for Withholding Proprietary Information from

Public Disclosure, CAW-18-4722, accompanying Affidavit, Proprietary Infonmtion Notice, and

Copyright Notice.

As Item 1 contains information proprietary to WestinghOWJe FJectric Company LLC

(''Westinghouse"), it is supported by an Affidavit signed by Westinghouse, the owner of the

information. The Affidavit sets forth the basis on which the information*may be withheld from

public disclosure by the Nuclear Regulatory Commission ("Commission") and addresses with

specificity the considerations listed in paragraph (b)( 4) of Section 2390 of the Commission's

regulations.

Accordingly, it is respectfully 1equcsted that the information which is proprietary to

Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2.390 of

the Commission's regulations.

Corrcspondence with respect to the copyright or proprietary aspects of the item listed above or

the supporting Westinghouse Affidavit should reference CAW-18-4708 and should be addressed

to James A. Gresham, Manager, Regulatory Compliance, Westinghouse Electric Company, 1000
        Westinghouse Drive, Building 2 Suite 259, Cranberry Township, Pennsylvania 16066.

Correspondence related to this transmittal should be addressed to:
                                Mr. W. Anthony Nowinowski, Executive Director

PWR Owners Group, Program tvlanagement Office

Westinghouse Electric Company

1000 Westinghouse Drive

Cranberry Township, PA 16066 If you have any questions, please do not hesitate to contact me at (805) 545-4328 or

Mr. \V. Anthony Nowinowslci, Program Manager of the PWR Owners Group, Program

rvlanagement Office at (412) 374-6855.

Sincerely yours,
         ~,~
        Ken Schrader, CC><) & Chairman

PWR Owners Group

PWROG-16043-NP-A                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                   A-74 U.S. Nuclear Regulatory Commission                                                    March 27, 2018
        00-18-62                                                                                 Page 3 of3 JKS:am

cc*     PWROG Analysis Committee (Participants of P A-ASC-1169)
                PWROGPMO

PWROG Steenng and Management Conuruttee

J Andrachek, Westinghouse

K. Lasswell, Westinghouse

J. Sinegar, Westinghouse

B. Benney, US NRC

Enclosure 1      PE-18-24-P/NP, Attachment 1, "RAls 4 and 5 Responses for PWROG-16043 Revision 2" (PA-ASC-1169)
        Enclosure 2.     Affidavrt for Withholding, CAW-184722 (Non-Proprietary) with accompanyrng

Affidavrt, Proprietary Information Notice and Copyright Notice

E/ectromcdJy Apprrmd&con1s an Authmbcaud 111 IM EIICtrornc Doamrmt Manapmart Sys1a,,.

PWROG-16043-NP-A                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                               A-75
     @*westinghouse- Fr:om; Roger Yohg Lu                                                                 Our Ref: PE:~8-24-NP

Phone: (803) 647-3426                                                                         Date: Mai:ch_ 15, 20:18
           _a-mall: tyr@westfnghouse com

Sl,tbject* Response to PWR09 Topical Report PWROG-1~P ~s 4 and-5 To: James-P. Molkeothin                   jiij G. Sinegar

cc: 'pwRQG                                           .

Attachecl'are the responses to RAls 4 and 5 related t~.tt,e                PWR9G         topical Report PV'v'.ROG-16043'P .

.Pfoprtetary Information is .sboWn In brackets.                      Q~ns or comments sholll~ be djr~d to the

undersign~
                          ROQ8fl 'i'. Lu*
                         P\NR F.ueJ Technology

.'verlfler:         Jane x. Jiang*,
                          themial~Hyc!raulic and Se!smlt; Engin~nng

Approver.          Kevin T. LassweM*, Manag~r.

thermaHfydraullc and ~le; Engineering

' [Jlcoonniatlly /lppim'<X_l jl.cco,;,.b 3l1l A**bauii:alcl iit Lho ~ J)cx.wncu1,*~ Sy,.lclur

t Uuc,i, P06>1 Verificdoii (Jl'V) 005 =1 w 'Yl.'Dfy th~ Jl,1<.'\ttO!lll n ~ ill tlJI.J' 0"8il!Jl ~ l v ~ Ch,:clJi,J 1mloli*
        tsillu.ch$XI t\rtlli,~tio l;l)MS.                                                                             *         *
PWROG-16043-N P-A                                                                                                             November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                   A-76 Wcsnnghouse Non-Propnetmy Class 3 PE-18-24-NP,
                                                                                                             Attaclnn cm I

March 15, 2018 Pagel of I

RAl4 The LTR states that beyond the use of simulated EOL grids, no modification was made to the NRC-
      approved testing and analysis methodologies documented In WCAP-9401-P-A and CENP0-1780P,
      Rev. 1-P. Therefore, NRC approval Is not being sought for anything beyond the proposed use of

simulated EOL grids to determine the allov,,able grid impact strength. In order to verify that NRC

review and approval beyond the limited scope described In the LTR is not necessary, the NRC staff                                 r

requests the following clarlflcatlon:
         4. In Section 2 2 of the LTR, the aDowable grid impact strength for CE and Westinghouse fuel are

discussed as [

(
      Response to RAI 4
                                                              ] a,c

RAIS

A new methodology is being proposed for Westinghouse and CE fuel to credit flowing water damping

In mitigation of the degradation In fuel mechanic behavior due to EOL effects on the spacer grids.

This methodology is proposed as an option for use in lieu of the still water damping credited In the

previously approved methodologies. In order to full;' understand how the proposed methodology is

intended to conservabvely capture the impact of flowing water on fuel asserrbly vibrations, the NRC

staff requests the following infonnation:
         5. Section 4 of the LTR discusses application of floo.Nlng water da"1)ing for EOL conditions. Please

clarify whether the EOL conditions, wlh flowing water damping, wlD be considered to bound BOL

conditions, or If BOL conditions wiU continue to be analyzed separately 'Mth the existing stlU water

damping methodology. If the EOL condition analysis Is intended to bound BOL concfrtions, please

provide information Justifying this conclusion.

Response to RAJ 5 The EOL conditions that considered flowing water damping do not bound BOL concfrtions. The BOL

conditions wlll continue to be analyzed separately with the existing still water damping methodology.

-Tors record WH tnal epprowd a, 3/'l5/2fJ18 11 17-51 AM ( T1n -em,,nl wu added by lhe PRIME syst,m upm u valodllllon)
PWROG-16043-NP-A                                                                                                        November 2019 Revision 2

'-
                             WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                  A-78 June 20, 2017 Mr. W. Anthony Nowlnowskl, Program Manager

PWR owners Group, Program Management Office

_)
         Westinghouse Electrlc Company

1000 Westinghouse Drive, Suite 380
         Cranberry Township, PA 16066 SUBJECT:         ACCEPTANCE FOR REVIEW OF THE PRESSURIZED WATER REACTOR

OWNERS GROUP TOPICAL REPORT PWROG-16043, "PWROG PROGRAM

TO ADDRESS NRC INFORMATION NOTICE 2012-09: IRRADIATION

EFFECTS ON FUEL ASSEMBLY SPACER GRID CRUSH STRENGTH FOR

WESTINGHOUSE AND CE PWR FUEL DESIGNS" (CAC NO. MF9280)
         Dear Mr. Nowinowskl:
         By letter dated February 1, 2017 (Agencywlde Documents Access and Management System

(ADAMS) Accession No. ML170398050), the Pressurized Water Reactor OWners Group

(PWROG) submitted Topical ReJX>rt (TR) PWROG-18043-P, Revision 2, "PWROG Program to

Address NRC I nformatlon Notice 2012-09: "t rradlatlon Effects on Fuel Assembly Spacer Grid

Crush Strength" for Westinghouse and CE PWR Fuel Designs," to the U.S. Nuclear Regulatory

Commission (NRC) staff for review.                              ,
         The NRC staff has found that the material presented Is sufficient to begin our review. The NRC

staff expects to issue Its request for addttlonal Information by March 30, 2018, and Issue Its draft

safety evaluation (SE) by September 3, 2018. This schedule Information takes In consideration

the NRC's current review priorities and available technical resources and may be subject to

change. If modifications to these dates are deemed necessary, we will provide appropriate

updates to this information. The review schedule milestones were discussed and agreed upon

In a telephone conference between PWROG Project Manager, Chad Holderbaum, and the NRC

staff on June 14, 2017.                        '
         Section 170.21 of T1tle 10 of the Codi, of Federal RegulaticJm requires that TRs are subject to

fees based on the full cost of the review.

Section 1.4 of PWROG-16043-P specifies the llmled scope review being requested by

PWROG. This section clearly states that this topical does not "revise and or modify the current

NRG-approved grid and fuel assembly test methods, or the fuel assembly seismic and loss-of- coolant accident analysis methodologies, processes and codas.* Section 1.3 of

PVVROG-16043-P goes on to state that this topical report "does not supercede the

NRG-approved TRs WCAP-9401-P-A (Reference 1-3) and CENPD-178-P, Rev. 1-P

(R,eference 1.4).* The NRC staff understands the linitad scope review being requested and

does not intend to expand its review Into the underlying, legacy seismic methods within

WCAP-9401-P-A or CENPD-178-P, Rev. 1-P.

However, issues Identified within these legacy methods during recent and ongoing new reactor

reviews (I.e., AP1000 and APR1400) may need to be addressed prior to use of the revised end

- of life fuel characteristics and damping coefficients in PWROG-18043-P.

(
PWROG-16043-NP-A                                                                                         November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                  A-79 W. A. Nowinowskl                                   -2- As a result, the staff's safety evaluation may Include a !Imitation and condition defining Issues

with the legacy methods, which need to be resolved prior to use of PWROG-16043-P.

As with all TRs, the SE will be reviewed by the NRC's Office of the General Counsel (OGC) to

determine whether rt falls within the scope of the Congressional Review Act (CRA) During the

course of this review, OOC considers whether any endorsement or acceptance of a TR by the

NRC amounts to a rule as defined in the CRA. If this initial review concludes that the SE, with

its accompanying TR, may be a rule, the NRC will forward the package to the Offtce of

Management and Budget (0MB) for further review and consideration. Any review by 0MB

would impact the schedule for the issuance of the final SE. If you have questions regarding this

matter, please contact Brian Benney at (301) 415-2767.

Sincerely, IRA/
                                                           Dennis C Morey, Chief

Licensing Processes Branch

DIVision of Policy and Rulemakmg

Office of Nuclear Reactor Regulation

Project No. 694 PWROG-16043-NP-A                                                                                        November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                A-80
         w_. A. N9vfirrovjski

SUBJECT:        ACCEP-TANCt. FOR.REVIEW OF n-iE PR.E$SU~ZEO WATER REACJOR

9~RS' GRQl;JPT0et~ ~PQ~J P_WRdG.:1_~. ~~00-PROQRAM,'
                         JO ADDRESS N~ !~FORMATION NQTICE 2012-09:_ ,~RADIATION. _
                         EFFECTS ON FUEL ASSEMBLY Si.>ACER GRID CRUSH STRENGTH FOR

WESTINGHOUSE'AND CE P~VR ft,JEL DESIGNS" (CAC NO.*MF.92eD)
                         DATED: JUNE 20, '2017 DISTRIBUTION:
        'PUBLIC, - - - .                       RldsNrrDs$Ss!b                     !<Hsueh*, NRR *
         RldsACRS MaUCr.R

* RtdsNrrOpr                         Rlukes, NRR

RldsNn:LADHarrlson                    ~s{'JJT[)ri                        Plf'B r/f

Rld~~ile;eot~r                       *B!3ehney, NR~
         f{idsNrrDptplp(?                     *F'_pifford, NRR:
                                   ..

ADAMS'Accession No* _ ML1n23A125:''              *concurr'edvfa e-mail       - *-    NRR*106 OFFICE       NRR/DPR/P!.PB/eM              . NRRIDP8/PLPBll:.A*        NRRIQSS/SNPBIBG*
           NAME , _B8enney_                             DHamson                    RLuR&s

DA~-       -5110111                      I: 519117*        -        
* 5126/17 -
          'OFFICE_ NRR/DSS/TA                           NRR/DPR/PU?BIBC            _)
                                                                                             - -*---
           NAME        'PC!lfford                     I OMorey                                           ;
           DATE         6/1/17                      : , 6/20{17 -               I

'
              -- -          - -- -    . -                   .

*OFFICI~ ~CQRD*COPY

-
                                                                                                          -
PWROG-16043-NP-A                                                                                      November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                                  A-81 rPrcgram Managemeot Office

20 International DT!Ve

Wlfldror, E:oni:,ec!icut 08Gl5 Febrpmy l, 2017'
           1)ocument~ootrolDesk

u:s. Nucl~ Regulatory Commissi<i!l

iI ~55 Ro~Ule Pike

Roel-ville, MD 208~2-2738
            &ubject:*          PWR Owners Group                                            .

Sybmittlll .of PWROG-16043-P. Revi!fion l. *"PWROG Program .t9 Address NRC Jnfognatton Nod&#xa3;(i:2012:o9.:* "Irradbtion -Effajs                              on.

Fuel .AJ,sembly SJ1&#xa5;er Grief' Cru>>h *Sti;engtb" t'9r Westingbou:re -and.

CF: PW!} Fgel Ds,igl!!," P~--ASC-:11&sect;2R2 Reference:.        NRC *lnfonnntlon Notke 2012-09. "Irradiation Effects on*                                 Fuel

W!J!hly ~IJ?ce~ G[_id ~t!'ffl ~!~gth*,n dii!ed J~_n*e ~s.*2m;
            The ptllllose of' this lefter, .is 'to '8Ubmit Pressurized Water Reactor Owners Group

(PWROG) 'fopical Report (TR), P\YROG-16043-P, Rcyision 2.. -PWROG Program io

Address NRC Inf_onnation Notice 2012-09: "Irradiation Effects on Fuel ~ l y , Spacer

~d CIU6h Strength" for \vest.inghouse *arid OE. PWR FueJ, Designs,~ in nccofiliih~ with

the Nuclear Refilllaiory Comm~ion (N_RC) TR program for review and acceptance for

reforencing in regljlatory actions. PWROG--16043-P~ Revision 2 is provided in Enclosme

l

PWR.00-16043-P, Revision 2 addresses the issue identified in NRC Information Notice

2012-09 by applying the approach 1ba~ was u.scd to a<ldres.5 ibc End ofl.ifl} (EOL) effi.-gts

for the API000 1 Core Reference Report APP-GW-GLR:.153, Rev.' 1. ''A:P-1000' Core

Reference Report_** .PWR00-16043-P. ~ision 2 djscusses the uppJicability for

determining fuel assembly characteristics and damping codlicicnts at EQL conditions

ru1,~.jho. !ll!pects Tor* which NRC approval is .~~ed..P\VR.00-16043-P, R~vi;sion *2
             ~ not revise arid/or mcx!ify, the current *grid.and ~f. llB8elDblytc,st me~ or the fucl

assembly seismic> and LOCA anajysis mcthodologi!!S. ~ and codes thm were

previously appr9v!!d by NR~.

E,nclosure. 3.       contams Westinghouse ::tutho~tiori letter CAW;.J7-4S30. -tpc

a(?COinpanymg affidavit. Proprietary Inf0ilnation N0(1oo;_ ~ Cop~t Notice:
            1
           -   APtOIIO :md CF,16NGF lll"CQ trmnarl; o r , ~ tilldcnm',; ofWes!Jngh<:eie fficctrio ~ L i e , ~ Afllh:i.tcs .

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PWROG-16043-NP-A                                                                                                            November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                A-82 U.S. Nuclear Regulatory CoillilllBsion                                    February 1, 2017 OG-17-12 PWROG-16043-P, Revision 2, contains information proprietary to Westinghouse Electnc

Company LLC, therefore it IS supported by an affidavit signed by Westinghouse, the

owner of the information. The affidavit sets forth the basis on which the information may

be withheld from public disclosure by the Commiss10n and addresses with specificity the

considerations listed in paragraph (bX4) of Section 2.390 of the Comnuss1on's

regula11.ons.

Accordingly, it IS respectfully requested that this information wlu.ch is proprietary to

Westinghouse, be wrthheld from public disclosure in accordance with 10 CFR Section

2.390 of the Commission's regulat10ns

Correspondence with respect to the copyright or proprietary aspects of the mformation

identified above or the supporting Westinghouse affidavit should reference CAW-17-
          4530, and should be addressed to Mr. J. A Gresham, Manager, Regulatory Compliance, Westinghouse Electnc Company LLC, 1000 Westinghouse Drive, Building 3 Suite 310,
          Cranberry Township, Pennsylvania, 16066.

TR Qassificatiop; As dIBCussed above, this TR addresses the issue associated with the

rrradiation effects on fuel assembly spacer grid strength identified in NRC Information

Not.ice 2012-09, via a generic licensing action, that will be used for evaluating the

structural integrity of fuel assemblies under faulted condition loads (seism1c and LOCA)
          for Westinghouse and CE fuel designs at EOL conditions, on a plant-specific basIB.

Specialized Resource Availability: This TR is bemg submitted to the NRC for review

and approval so that the NRC approved version can be utilized for performing plant- specific evaluations of the structural mtegrity of fuel assemblies under faulted condition

loads (seism1c end LOCA) for Westinghouse end CE fuel designs at EOL conditions

NRC approval of the generic TR will provide a common approach that will be utilized to

address the EOL effects on fuel assembly space grid strength in fuel assembly structural

mtegrity evaluations

This Jetter transmits four copies of PWROG-16043-P, Revision 2 (Enclosure 1) and one

copy of PWROG-16043-NP, Revmon 2 (En.closure 2)
           Applicabllitvi 1lns TR is applicable to the Westinghouse and CE Nuclear Steam Supply

System (NSSS) plants that are participating m the PWROG program, PA-ASC-1169R2, that developed this TR

Request for Review Fee w alyer

The PWROO will be requesting that a foe waiver be considered for the NRC review of

PWROG-16043-P, Revision 2 pursuant to the prov1S1ons of 10 CFR

170.ll(a)(lXiiXA). PWROG-16043-P provides a common approach that will be ut1hzed

to address the EOL effects on fuel assembly space grid strength in fuel assembly

structural integrity evaluations. NRC approval of the TR will ensure that the EOL effects

on fuel assembly space grid strength in fuel assembly structural integnty evaluations are

considered m these evaluations Therefore the review of tlu.s TR will support ongoing

PWROG-16043-NP-A                                                                                     November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                                                A-83 U.S. Nuclear Regulatory Commission                                        February 1, 2017
           00-17-12                                                                        Page 3 of4 NRC generic regulatory improvoments'efforts associated with the issue of EOL effects

on fuel assembly space grid strength in fuol assembly structural integrity evaluations.

During the fee waiver decision period, the PWROG respectfully requests the NRC Staff

to perform its acceptanco review of PWROG-16043-P. RCVtsion 2 1be PWROG will

assume the responsibility of payment of the NRC review fees accrued both during the

acceptance review, and during the review, if tho fee waiver is not approved.

NRC Review Schedule

The PWROG requests that the NRC complete theu review of the TR by August 2018.

Correspondence related to this transmittal should be addressed to:
                               Mr. W. Anthony Nowinowski, Program Manager

PWR Owners Group.. Program Management Office

Westinghouse Electric Company

1000 Westinghouse Drive

Suite 380
                                  Cranberry Township.. Pennsylvania, 16066 If you have any quest10ns, please do not hesitate to contact me at (205) 992-7037 or Mr.

W. Anthony Nowinowski, Program Manager of the PWR Owners Group, Program

Management Office at (412) 374-6855 Sincerely yours, Jack Stringfellow, Chief Operating Officer and Chairman

PWR Owners Group

NJS.WAN

Enclosures 1 and 2. Four copies of PWROG-16043-P, Revision 2, "PWROG Program

to Address NRC Information Notice 2012-09: "Irradiation Effects on Fuel Assembly

Spacer Grid Crush Strength" for Westmghouse and CE PWR Fuel Designs" (Proprietary)
           and one copyof PWROG-16043-NP. Revision 2 Enclosure 2: One copy of the Appltcntion for Withholding, CAW-17-4530 (Non- proprietnry) with the accompanying affidavit, Proprietary Information Notice and

CoP)nght Notice

PWROG-16043-N P-A                                                                                    November 2019 Revision 2

WESTINGHOUSE NON-PROPRIETARY CLASS 3                       A-84 U.S. Nuclear Regulatory Commission              February 1, 2017 OG-17-12                                             Page 4of4 cc:    PWROG Management Committee

PWROG Analysis Committee

PWROG Steenng Commrttee

PWROG Licensmg Commrttee

PWROGPMO

J. Gresham, Westinghouse

J. Andrachek, Westinghouse

J. Moorehead, Westinghouse

B. Benney, US NRC

J. Sinegar, Westinghouse

N Marshall, Wesunghouse

J. Norrell, Wesunghouse

R. Lu, W estmghouse

J. Jiang, W estmghouse

PWROG-16043-NP.:A                                                          November 2019 Revision 2}}

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