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Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis, Areva Document No. 32-9281804-000 (Non-Proprietary Version)
	ML18129A332
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Site:	Limerick
Issue date:	05/04/2018
From:	; AREVA, Exelon Generation Co
To:	; Office of Nuclear Reactor Regulation
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l_ -Attachment 6 "Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis -Proprietary," AREVA Document No. 32-9281804-000, Non-Proprietary Version CALCULATION

SUMMARY

SHEET (CSS) AREVA Document No. 32 -9281804 -000 Safety Related: ~Yes D No --------------------

Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Title Proprietary PURPOSE AND

SUMMARY

OF RESULTS: Purpose: The purpose of the present analysis is to determine from a fracture mechanics viewpoint the suitability of leaving a degraded J-Groove weld in the Limerick Unit 2 Nuclear Power Plant reactor pressure vessel following the repair of a leaking instrumentation nozzle N-16D. It is postulated that a radial-axial corner flaw exists through the entire J-Groove weld and buttering.

This document complements previous flaw evaluation work that supported a one cycle justification of plant operation.

Summary of Results: A fatigue and SCC crack growth and fracture mechanics evaluation of the postulated flaw in the as-left J-Groove weld and buttering at the Limerick Unit 2 Instrumentation Nozzle N-16D has been performed.

Based on a combination of linear elastic and elastic-plastic fracture mechanics analyses, the postulated flaw is shown to be acceptable for 40 years after the installation of the modification utilizing the safety factors in Table 1-1, and the applicable J-R Curves from Regulatory Guide 1.161 [14]. Proprietary information in the document is identified by bolded brackets ([ ]). The proprietary version of this document is 32-9277252-000.

The following table summarizes the total pages contained in this document.

I Section I Main Body I Appendix A I Appendix B I Total I I Paqes I 40 I 10 I 11 I 61 I If the computer software used herein is not the latest version per the EASI list, AP 0402-01 requires that justification be provided.

THE FOLLOWING COMPUTER CODES HAVE BEEN USED IN THIS DOCUMENT:

CODENERSION/REV CODENERSION/REV ANSYS 16.0 (See Section 5.1) AREVA Inc. THE DOCUMENT CONTAINS ASSUMPTIONS THAT SHALL BE VERIFIED PRIOR TO USE DYes IZI No Page 1 of 61 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Review Method: IZ] Design Review (Detailed Check) D Alternate Calculation Does this document establish design or technical requirements?

DYES IZ] NO Does this document contain Customer Required Format? DYES IZ] NO Signature Block P/R/A/M Name and Title and Pages/Sections (printed or typed) Signature LP/LR Date Prepared/Reviewed/Approved Luziana Matte LR MATTE Technical Consultant 2/14/2018 LP Tom Riordan TE RIORDAN LR Engineer IV 2/14/2018 David Cofflin DRCOFFLIN Unit Manager 2/15/2018 A Notes: P/R/A designates Preparer (P), Reviewer (R), Approver (A); LP/LR designates Lead Preparer (LP), Lead Reviewer (LR); M designates Mentor (M) All Pages / All Sections All Pages / All Sections Alt Pages / All Sections In preparing, reviewing and approving revisions, the lead preparer/reviewer/approver shall use 'All' or 'All except _' in the pages/sections reviewed/approved.

'All' or 'All except_' means that the changes and the effect of the changes on the entire document have been prepared/reviewed/approved.

It does not mean that the lead preparer/reviewer/approver has prepared/reviewed/approved all the pages of the document.

Project Manager Approval of Customer References and/or Customer Formatting (N/A if not applicable)

Name Title (printed or typed) (printed or typed) Signature Date David Skulina Project Manager DJSKULINA 2/15/2018 Page2 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Record of Revision Revision Pages/Sections/Paragraphs No. Changed Brief Description

/ Change Authorization 000 All Original Release. The proprietary version of this document is 32-9277252-000

-* Page3 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Table of Contents Page SIGNATURE BLOCK ................................................................................................................................

2 RECORD OF REVISION ..........................................................................................................................

3 LIST OF TABLES .....................................................................................................................................

5 LIST OF FIGURES ...................................................................................................................................

6 1.0 PURPOSE .....................................................................................................................................

7 2.0 ANALYTICAL METHODOLOGY

...................................................................................................

9 3.0 ASSUMPTIONS

..........................................................................................................................

18 4.0 DESIGN INPUTS ........................................................................................................................

19 5.0 COMPUTER FILES .....................................................................................................................

27 6.0 CALCULATIONS

.........................................................................................................................

32

7.0 CONCLUSION

S

..........................................................................................................................

39

8.0 REFERENCES

............................................................................................................................

40 APPENDIX A: OPERATING STRESS ANALYSIS .............................................................................

A-1 APPENDIX B: FLAW EVALUATIONS

................................................................................................

8-1 Page4 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary List of Tables Page Table 1-1: Safety Factors for Flaw Acceptance

.......................................................................................

8 Table 4-1: RV and Instrumentation Nozzle Dimensions

........................................................................

19 Table 4-2: Component Materials

............................................................................................................

20 Table 4-3: RV Base Material, [ ] ..................................................................

21 Table 4-4: RV Cladding, [ ] ..................................................................

21 Table 4-5: Original Nozzle and J-groove Weld, ] ................................................................

21 Table 4-6: Replacement Nozzle, New Weld Build-up, New J-groove Weld, [ ] .....................

22 Table 4-7: Operating Transients and Cycles .........................................................................................

25 Table 4-8: Stress Result Files ................................................................................................................

26 Table 5-1: Computer Files .....................................................................................................................

27 Table 6-1: LEFM Results -Crack Tip Position [ ] ..............................................................................

33 Table 6-2: EPFM Results -Crack Tip Position [ ] (USE= [ ] ) ...........................................

34 Table 6-3: EPFM Results -Crack Tip Position [ ] (USE= [ ] ) ...........................................

35 Table A-1: [ Table A-2: [ Table A-3: [ Table A-4: [ ] ................................................................................................

A-3 ] .........................................................................................................................

A-4 ] .....................................................................................................

A-5 ] ......................................................................................................................

A-6 Table A-5: Time Points Selected for Stress Run .................................................................................

A-8 Table 8-1: SIFs -Welding Residual Stress .........................................................................................

8-1 Table 8-2: SIFs -Steady State Normal Operating Condition

..............................................................

B-2 Table 8-3: SIFs -Emergency Transient

[ -] ......................................................................

8-3 Table 8-4: SIFs -Faulted Transient

[ ] .......................................................................................

8-4 Table 8-5: Fatigue Crack Growth for Transient

[ ] ...................................................................

8-5 Table B-6: Fatigue Crack Growth for Transient

[ ]. ..................................................................

8-6 Table 8-7: Stress Corrosion Flaw Growth ...........................................................................................

B-7 Table 8-8: EPFM Evaluation for [ ] (USE= [ ] ) .......................................................

8-8 Table 8-9: EPFM Evaluation for [ ] (USE= [ ] ) .......................................................

8-9 Page5 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary List of Figures Page Figure 1-1: Schematic of Nozzle Replacement Implementation

..............................................................

7 Figure 2-1: Finite Element Model Isometric View ..................................................................................

11 Figure 2-2: Crack Fronts ........................................................................................................................

12 Figure 2-3: Initial Flaw Size ....................................................................................................................

13 Figure 4-1: J-R Curves as a Function of Temperature (USE= [ ] ) .........................................

23 Figure 4-2: J-R Curves as a Function of Temperature (USE= [ ] ) .........................................

24 Figure 4-3: Weld Residual Stress Mapped to Crack Front 1 (psi) .........................................................

26 Figure 6-1: Limit Load Model Geometry ................................................................................................

36 Figure 6-2: Limit Load Model Finite Element Mesh ...............................................................................

37 Figure 6-3: Equivalent Stresses at the Final Load Step (psi) .................................................................

38 Figure A-1: [ Figure A-2: [ Figure A-3: [ Figure A-4: [ ] .......................................................

......................................

A-3 ] ........................................................................................................................

A-4 ] .....................

..............................................................................

A-5 ] .....................................................................................................................

A-6 Figure A-5: Locations for Thermal Gradients

.......................................................................................

A-7 FigureB-1:

J-TDiagramfor

[ ] (USE= [ ]) ............................................................

8-10 Figure B-2: J-T Diagram for [ ] (USE= [ ] ) ............................................................

B-11 Page6 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

1.0 PURPOSE

Instrument nozzle N-16D was found leaking at the Limerick Generating Station (LGS), Unit 2, Reactor Vessel (RV) during the Spring 2017 outage. The cause of the leakage was not determined.

However, based upon industry experience, the most likely cause is intergranular stress corrosion cracking through either the [ ] Groove weld or the [ ] nozzle. A half nozzle repair was designed in which an outboard portion of the existing nozzle was removed and a replacement nozzle attached to a new [ ] weld pad on the OD of the RV. Due to the emergent nature of the repair, AREVA performed a one-cycle justification for the nozzle repair to support the Relief Request and subsequent NRC approval for plant restart. The repair is illustrated in Figure 1-1 and is described in more detail in the design drawing [ 1]. Figure 1-1: Schematic of Nozzle Replacement Implementation The purpose of this task is to determine from a fracture mechanics viewpoint the suitability of leaving a degraded I-groove weld in the Limerick Unit 2 Nuclear Power Plant RV following the repair of instrumentation nozzle l 6D. Since a potential flaw in the I-groove weld and buttering cannot be sized by currently available destructive examination techniques, it is conservatively assumed that the "as-left" condition of the remaining groove weld includes degraded or cracked weld material extending through the entire I-groove weld material and [ ] butter material.

Page?

AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary It is conservatively postulated that a radial-axial corner flaw exists through the entire J-groove weld and buttering and would propagate into the low alloy steel reactor vessel material by fatigue crack growth under cyclic loading conditions.

Although some investigators have suggested that flaw propagation due to stress corrosion cracking would occur at a higher rate than fatigue, stress corrosion cracking is not deemed a credible growth mechanism under normal conditions.

It is only included in the present flaw evaluation as an extremely conservative tactic. The applicable code is ASME Section XI, 2007 Edition with Addenda through 2008 (Reference

[2]). If the service life of the component is shown to be limited, an alternate approach of using ASME Section XI Code Case N-749 (Reference

[3]) as modified by the Nuclear Regulatory Commission (see Reference

[8]) will be considered in the evaluation.

Acceptance of each postulated flaw is determined based on available fracture toughness or ductile tearing resistance using the safety factors outlined in Table 1-1. Table 1-1: Safety Factors for Flaw Acceptance LEFw 1> Operating Condition Evaluation Method Fracture Toughness/

Ki Normal/Upset KJc fracture toughness

.../10 = 3.16 or/2 = 1.41 <1 a. lb) Emergency/Faulted K1c fracture toughness

'V2 = 1.41 (le) EPFM Based on Limited Ductile Flaw Extension<

2> Operating Condition Evaluation Method Primary

Secondary Normal/Upset Jo.I limited flaw extension 2.0 1.0 Emergency/Faulted Jo.I limited flaw extension 1.5 1.0 EPFM Based on Limited Ductile Flaw Extension and Stability<

3> Operating Condition Evaluation Method Primary Secondary Normal/Upset JIT based flaw stability 2.14 1.0 Normal/Upset Jo.I limited flaw extension 1.5 1.0 Emergency

/Faulted J/Tbased flaw stability 1.2 1.0 Emergency/Faulted Jo.I limited flaw extension 1.25 1.0 Notes: (I) LEFM safety factors are from IWB-3613 of ASME Section XI (Reference

[2]). a. Per IWB-3613(a), for conditions where pressurization does not exceed 20% of the design pressure during which the minimum temperature is not less than RTNoT: KI< Kic /,/2 b. Per IWB-3613(b), for Normal and Upset conditions excluding those described in IWB-3613(a):

KI< Kic /,/IQ (criteria ofIWB-3612(a))

c. Per IWB-3613(c), for Emergency and Faulted conditions:

KI< K1c ;,/2 (criteria ofIWB-3612(b))

(2) EPFM safety factors based on Section 3.1 of Code Case N-749 (Reference

[3]). (3) EPFM safety factors based on Section 3.2 of Code Case N-749 (Reference

[3]). Page 8 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary

2.0 ANALYTICAL

METHODOLOGY The basic analytical methodology is outlined below. Details are provided in the following subsections.

1. Postulate a radial flaw in the J-groove weld and buttering, radial with respect to the nozzle axis extending from the inside corner of the penetration to the interface between the J-groove weld/Butter and the reactor vessel shell. Initial flaw size, a 0 , is characterized by the distance along the penetration bore, from the inside surface of the cladding to the weld-to-weld

/RV shell interface.

Since hoop stresses in the J-groove weld are generally higher than axial stresses at the instrumentation nozzle penetration, the preferential direction for cracking is axial relative to the RV shell. 2. Develop a three-dimensional finite element crack model of the reactor vessel shell in the vicinity of the instrumentation nozzle penetration, with crack tip elements capable of representing several flaw depths with the initial flaw depth being along the interface between the weld and the low alloy steel base metal. These models will be used to obtain stress intensity factors at various positions along the crack front for residual and operating stresses, with crack face pressure.

3. The combined residual plus operating stresses are obtained by utilizing the model developed by the WRS analysis (Reference

[15]). The final simulation provided by the WRS analysis is the welding of the new Groove weld to the new replacement nozzle and weld pad. The combined residual plus operating stresses are obtained by the following sequential steps: a. Simulate three steady state operating conditions cycles after the welding of the new J-Groove weld by applying the corresponding temperature and pressure as a static load step. Each steady state cycle includes going from ambient conditions (zero pressure and room temperature) to operational pressure and temperature then going back to ambient conditions.

b. Simulate the key operating transients defined in the one cycle justification analysis (Reference

[4]). A thermal transient analysis is performed for each applicable transient by applying the transient temperatures and heat transfer coefficients on all wetted surfaces.

Defining the locations of interest for thermal gradients within the model, obtaining values of thermal gradients for the entire transient from runs on the thermal model, and selecting the time points for structural runs. Applying pressure and temperature on the structural model for the time points identified in the previous step to obtain stresses resulting from pressure and thermal gradients.

The sequence of each applicable transient is defined as follows: i. Three cycles of the [ ] are performed at the end of step 3.a above followed by one cycle of steady state operating condition.

ii. One cycle for each remaining applicable transients is performed at the end of step 3.b.i above. c. The combined residual plus operating hoop stresses applicable for evaluating a postulated remnant flaw in the as-left J-groove weld are extracted along the nodes on the symmetry plane that slices the RV shell in the vertical direction, referred to as the "0-Degree" plane for ease of reference.

4. Develop a mapping procedure to transfer stresses from the uncracked finite element stress analysis model to the crack face of the cracked models. This will enable stress intensity factors to be calculated for arbitrary stress distributions over the crack faces utilizing the principle of superposition.

5. Obtain stress intensity factors for each loading condition at varying positions along the crack front by using the ANSYS KCALC command. 6. Calculate fatigue flaw growth, in one week or one year increments, as appropriate, for cyclic loading conditions using operational stresses from pressure and thermal loads. Since the stresses used in the Page 9 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary fatigue flaw growth analysis are the combined residual plus operating stresses, the effect of the residual stresses on fatigue crack growth is captured by the R ratio, or K1,n;r!Ktmax*

Weld residual stress is a steady state secondary stress, and has only a mean stress effect. Also flaw growth due to stress corrosion cracking (SCC) is calculated in one week or year increments, as appropriate.

The total flaw growth is the combined fatigue and corrosion flaw growth. 7. Utilize the screening criteria of ASME Code Case N-749 (Reference

[3]) as modified by the NRC (Reference

[8]) to determine the appropriate method of analysis (LEFM or EPFM). For LEFM flaw evaluations, compare the stress intensity factors to the available fracture toughness, with appropriate safety factors. When the material is more ductile and EPFM is the appropriate analysis method, evaluate in accordance with ASME Code Case N-749 (Reference

[3]). A limit load analysis is performed to demonstrate that Items 3.l(c) or 3.2(a)(3) of Reference

[3] are satisfied.

Items 3.l(c) or 3.2(a)(3) requires that the primary stress limit of NB-3000 are satisfied, considering a local reduction of the pressure boundary area equal to the area of the flawed material.

2.1 Stress

Intensity Factor Solution The SIF solutions for the postulated flaw evaluated by fracture mechanics analysis are calculated using dimensional finite element models with crack tip elements.

The model includes the RV with existing J-Groove weld. An isometric view of the overall finite element model developed for this analysis is shown in Figure 2-1. A radial-axial flaw is postulated and analyzed and shown in Figure 2-2. Four finite element models are generated with a flaw size increment of [ ] , [ ] , and [ ] in order to capture the variation of SIF with the flaw sizes. The SIFs are calculated at a total of 25 positions along the crack front starting with position 1 at the RV ID and going to position 25 at the nozzle bore as shown in Figure 2-2. Stress intensity factors are calculated using the ANSYS KCALC command (Reference

[16]), which determines the stress intensity factors based on displacements in the vicinity of the crack tip. For "non-classical" flaw shapes with stress intensity factor calculated by the finite element method it is both difficult and unnecessary to prescribe an initial flaw size. In order to track the flaw size during fatigue crack growth any characteristic dimension may be used as the initial flaw size. For this calculation the initial flaw size, a 0 , is chosen to be the vertical distance along the penetration bore in the finite element model from the inside surface of the cladding to the butter/RV interface (see Figure 2-3). Stress intensity factors at flaw sizes between the modeled flaw sizes are linearly interpolated.

If the flaw size is larger than the largest flaw in the finite element model, the stress intensity factor is determined using the following scaling rule Where Kt(a 1) is a known SIF at flaw size a 1 and Kt(a 2) is the desired SIF at flaw size a 2. This approach follows from the fundamental expression for the stress intensity factor, K 1 = CJ../im, where for a given applied stress and geometry the stress intensity factor scales with the square root of flaw size. 2.1.1 Plastic Zone Correction The Irwin plastic zone correction is used to account for a moderate amount of yielding.

For plane strain conditions the correction is (Reference

[5], Eq. 2.63) r: =_..!._(K 1 (a))2 Y 6rc Cly Page 10 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Where KI(a) is the stress intensity factor at the actual crack size (a), and ay is the material's yield strength.

The effective crack size, ae, is calculated as ae =a+ ry The stress intensity factor at the effective flaw size is then calculated using the scaling law derived above as Figure 2-1: Finite Element Model Isometric View Page 11 iJ-1.)C' A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Figure 2-2: Crack Fronts Page 12 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Figure 2-3: Initial Flaw Size 2.2 Fatigue Crack Growth Fatigue crack growth is calculated using the fatigue crack growth rate model from Article A-4300 of Reference

[2] as follows: da ( )n dN = Co !1K1 Where !1K 1 is the stress intensity factor range in ksi'Yin, and da/dN is the crack growth rate in inches/cycle.

The crack growth rates for a surface flaw will be utilized since the postulated flaw(s) would result in the low alloy steel head being exposed to the primary water environment.

The detailed equations for calculating the fatigue crack growth rate are presented as follows. !1K1 = KMax -KMin R = KMin/KMax Page 13 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary 0 :5 R :5 0.25, !J.KI < 17.74 n = 5.95 5 = 1.0 C 0 = 1.02 X 10-12 5 n = 1.95 5 = 1.0 C 0 = 1.01 X 10-7 5 0.25 < R < 0.65, tJ.K 1 < 17.74[(3.75R

+ 0.06)/(26.9R

-5.725)]0*25 n = 5.95 5 = 26.9R -5.725 C 0 = 1.02 X 10-12 5 !J.K 1 17.74[(3.75R

+ 0.06)/(26.9R

-5.725)]0*25 n = 1.95 0.65 :5 R :5 1.00, !J.K 1 < 12.04 5 = 3.75R + 0.06 C 0 = 1.01 X 10-7 5 n = 5.95 5 = 11.76 C 0 = 1.02 X 10-12 5 n = 1.95 5 = 2.5 C 0 = 1.01 X 10-7 5 Additionally, per A-4300(b)(2) of Reference

[2], if the fatigue crack growth rate from light-water reactor environments is lower than air environments, the rate in air should be used. The fatigue crack growth constants for flaws in an air environment are: n = 3.07 Co= 1.99 x10*10 S S is a scaling parameter to account for the R ratio and is given by S = 25.72 (2.88 -Rf 3*07 where O :SR '.S 1 and LJK.1 = Kmax -Kmin* Page 14 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary

2.3 Stress

Corrosion Crack Growth Reference

[6] conducted a stress corrosion cracking (SCC) susceptibility assessment that is specifically applicable to the Limerick Unit 2 N16-D reactor vessel nozzle. According to Reference

[6], an extensive review was performed of BWR operating experience to determine if low alloy steel is susceptible to stress corrosion cracking (SCC). In most cases of through-cladding SCC cracks in BWR reactor vessels, sharp cracks were found to have arrested at the cladding-to-low alloy steel (LAS) interface.

Sometimes, superficial pitting in LAS was observed from exposure to reactor water. The reactor vessel LAS surface exposed to reactor coolant included both heat affected zone (HAZ) from [ ] cladding or from [ ] buttering and unclad ( unaffected) base metal. These cracking incidents indicate that it is very unlikely that sharp SCC cracks penetrating the [ ] J-Groove weld (on the reactor vessel inside surface) will lead to SCC in the HAZ of LAS exposed to BWR water chemistry.

Reference

[6] concludes that extensive operating experience indicates that SCC of the exposed low alloy steel is very unlikely.

However, this evaluation conservatively uses a constant SCC growth rate of [ ] based on the work presented in [ ] , Reference

[7]. 2.4 Linear Elastic Fracture Mechanics After crack growth is calculated the flaw is evaluated using Linear Elastic Fracture Mechanics (LEFM). Article IWB-3612 of Section XI (Reference

[2]) requires that the applied stress intensity factor be less than the available fracture toughness at the crack tip temperature, with appropriate safety factor, as outlined below. IWB-3 613 (a): For conditions where pressurization does not exceed 20% of the design pressure during which the minimum temperature is not less than RTNnr: K1<K1cl,./2 IWB-3613(b):

For Normal and Upset conditions excluding those described in IWB-3613(a):

K 1 < Kic 1,./10 (criteria ofIWB-3612(a))

IWB-3613(c):

For Emergency and Faulted conditions:

K 1 < Kic 1,./2 ( criteria of IWB-3 6 l 2(b)) In the above, Kie is the fracture toughness based on crack initiation for the corresponding crack-tip temperature.

In the evaluation of the above limits, a plastic zone correction is incorporated using the methodology described in Section 2.1.1. 2.5 Elastic-Plastic Fracture Mechanics Elastic-plastic fracture mechanics (EPFM) will be used as an alternative acceptance criteria when the flaw related failure mechanism is unstable ductile tearing. LEFM would be used to assess the potential for non-ductile failure, while limit analysis would be used to check for plastic collapse.

2.5.1 Screening

Criteria ASME Code Case N-749, Reference

[3] states that EPFM acceptance criteria are applicable to ferritic steel components on the upper shelf of the Charpy energy curve when the metal temperature exceeds the upper shelf transition temperature, Tc, The NRC has proposed a modification to the Code Case definition of Tc, which is given below (see Reference

[8]). Tc= 154.8°F + 0.82 X RTNDT (U.S. Customary Units) When the metal temperature exceeds Tc, EPFM analysis is applicable, otherwise LEFM analysis is applicable.

Page 15 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary 2.5.2 Flaw Stability and Crack Driving Force Elastic-plastic fracture mechanics analysis will be performed based on ASME Code Case N-749 (Reference

[3]) to evaluate crack driving force and flaw stability (if applicable).

Two possible sets of acceptance criteria for EPFM are defined in Code Case N-749:

Section 3.1 Acceptance Criteria Based Solely on Limited Ductile Crack Extension, or

Section 3 .2 Acceptance Criteria Based on Limited Ductile Crack Extension and Stability.

Section 3.1 of Reference

[3] states that the flaw is acceptable if the crack driving force, as measured by the applied J-integral (Japp) with appropriate safety factors applied to the loads, is less than the than the J-integral of the material CJma,) at a ductile crack extension of 0.1 inch (J 0_1). If the criteria of Section 3.1 of Reference

[3] are not met, the flaw may still be acceptable if the criteria of Section 3.2 of Reference

[3] are met. Section 3.2 allows lower safety factors for the crack driving force check, and additionally requires that flaw stability be evaluated with appropriate safety factors. The flaw stability analysis will be performed using a J-integral/tearing modulus (J-1) diagram to evaluate flaw stability under ductile tearing, where J is either the applied (Japp) or the material CJma,) J-integral, and T is the tearing modulus, defined as (Ela/) (8J/8a). Flaw stability and crack driving force assessments will utilize the safety factors from Code Case N-7 49 as outlined in Table 1-1. The general methodology for performing EPFM analyses is outlined below. E'= E/(J-v2) final flaw depth = a Total applied K/1 J= K 1 app K 1 due to residual stresses (secondary)=

K1wrs K1due to residual plus pressure=

K 1 p+wrs K1due to pressure (primary)=

K1p = K1p+wrs-K1wrs K 1 due to residual plus thermal loads (secondary)

OJ= K 1 s = K 1 app -K 1 P Safety factor on primary loads = SFP Safety factor on secondary loads = SF. Total applied K 1 with safety factors, K1* = SFP x K 1 p + SF. x K 1 s Note(]): The total applied K1app and the secondary K 1 s conservatively include the effects of weld residual stresses.

For small scale yielding at the crack tip, a plastic zone correction (see Section 2.1. l) is used to calculate an effective flaw depth based on 1 (Kt)2 ae = a + 6:,r O"y The above equation is used to update the total applied stress intensity factor based on the following equation:

Kf = Kt_fl-The applied J-integral is then calculated using the following relationship: (Kf)z Japp=~ The applied J-integral is checked against J 0_1 , demonstrating that the crack driving force falls below the J-R curve at a crack extension of 0.1 inch. Page 16 I __ _J A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary For flaw stability analysis, the final parameter needed to construct the J-T diagram is the tearing modulus. The applied tearing modulus, Tapp, is calculated by numerical differentiation for small increments of crack size (da) about the crack size (a), according to = !_ (lapp(a + da) -lap/a -da)) Tapp 0"2 2 da t The material J-T curve is determined as described in Section 4.2 by constructing the J-T diagram as shown below: J T Flaw stability is demonstrated at an applied J-integral when the applied tearing modulus is less than the material tearing modulus. Alternately, the applied J-integral is less than the J-integral at the point of instability.

2.6 Primary

Stress Analysis Items 3.l(c) and 3.2(a)(3) of Reference

[3] state that the flawed component must meet the primary stress limits of NB-3000, Reference

[17], assuming a local area reduction of the pressure retaining membrane that is equal to the area of the flaw. To evaluate the requirement, article NB-3228.1 of Section III of the ASME Code [17] is utilized.

NB-3228.1 states that the limits on General Membrane Stress Intensity (NB-3221.1), Local Membrane Stress Intensity (NB-3221.2), and Primary Membrane plus Primary Bending Stress Intensity (NB-3221.3) need not be satisfied at a specific location if it can be shown by limit analysis that the specified loadings do not exceed thirds of the lower bound collapse load. The yield strength to be used in these calculations is l.5Sm. Per NB-3112.1 (a) the Design Pressure shall be used in showing compliance with this limit. Page 17 0 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

3.0 ASSUMPTIONS

3.1 Unverified

Assumptions No unverified assumptions are used in this calculation.

3.2 Justified

Assumptions The following justified assumptions are used in this calculation:

1. For fatigue crack growth calculations, cycles are assumed to accumulate at a linear rate, i.e., in each year the number of cycles utilized is the total number of design cycles divided by the plant design life. This assumption is reasonable since experience shows that linear rates generally envelope the accumulation rates observed for transients based on plant operating experience.

3.3 Modeling

Simplifications The following modeling simplifications are used in this calculation:

Page 18 0 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary

4.0 DESIGN

INPUTS 4.1 Geometry The detailed dimensions of the instrumentation nozzle N-16D modeled in the i:is-left J-Groove weld analysis are obtained from References

[1], [10], and [11]. Key dimensions are listed in Table 4-1. Table 4-1: RV and Instrumentation Nozzle Dimensions Description Value Reference(s)

Shell radius to base metal ID [ ] [1] Cladding thickness (nominal)

[ ] [10] [ Shell thickness

[ ] [1] Original Weld buildup thickness

[ ] [10] [ Original Instrumentation Nozzle ID (towards the ID of the shell) [ ] [10] [ Original Instrumentation Nozzle OD (towards the ID of the shell) [ ] [10] [ Original Instrumentation Nozzle Bore ID (towards the ID of the [ ] [10] [ shell) Repair Weld pad thickness

[ ] [1] Replacement Instrumentation Nozzle ID [ ] [11] Replacement Instrumentation Nozzle OD [ ] [11] Replacement Instrumentation Nozzle Bore ID '[ ] [11] ] ] ] ] ] Page 19 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

4.2 Materials

4.2.1 Material

Specifications The material designations of each component are listed in Table 4-2 per References

[1], [9], [10], and [11]. Table 4-2: Component Materials Component RV, Base Material RV, Cladding Original Nozzle Original J-groove Weld Old Weld Buildup New Weld Buildup Replacement Instrumentation Nozzle Replacement Nozzle J-groove Weld Material [ [ [ [ [ [ [ [ Note (1 ): The inside surface of the RV is [ [l]). Compatible material properties of [ are assumed for the [ ] weld material.

Note (2): Compatible material properties of [ [12] are also assumed for the [ ] (I) ] ] ] ] (2) ] (3) ] (4) Reference(s)

[1] [10] [1] [1] [9] [1] [11] [1] ] ( [ ] Reference

] from Reference

[12] ] from Reference

] weld materials.

Note (3): The material properties of the original weld buildup material on the RV shell is assumed to be [ ] per direction provided in Section 6.0 ofreference

[9]. Note (4): For the replacement weld material [ ] , properties of [ ] are assumed from Reference

[12]. Page 20 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

4.2.2 Mechanical

Material Properties The material properties of the existing components are taken from the Section III analysis, Reference

[13]. Per Reference

[13], properties are taken from Reference

[12]. The material properties for each component are provided in Table 4-3, Table 4-4, Table 4-5, and Table 4-6. Table 4-3: RV Base Material, [ ] Temp E I v a Sm Sy ksi ksi ksi Su I Table 4-4: RV Cladding, [ ] Temp E V (l psi in/in/°F Table 4-5: Original Nozzle and J-groove Weld, [ ] Temp E V (l OF psi in/in/°F Page 21 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 4-6: Replacement Nozzle, New Weld Build-up, New J-groove Weld, [ ] Temp E V a Sm OF psi in/in/°F ksi 4.2.3 Fracture Material Properties Per Reference

[10] ( [ ] ), [ ] EFPY adjusted RTNnT (ART) of the RV shell plate at the location of nozzle N-16D ( [ ] ) is [ ] . From Article A-4200 of Reference

[2], the fracture toughness for crack initiation, Kie, is calculated as follows: Kie = 33.2 + 20.734 X e[O.OZ(T-RTNvr)]

Where Tis the crack tip temperature, Kie is in units of ksi-Vin, and T and RT NDT are in units of °F. In the present calculations, K 1 c is limited to a maximum value of [ ] (upper-shelf fracture toughness).

The crack initiation Krc upper shelf toughness of [ ] is achieved at T-RTNvr> [ ] . The J-integral resistance (J-R) curve, needed for the EPFM method of analysis, is obtained from the following correlation for reactor pressure vessel plate in Regulatory Guide 1.161, Section 3.3.1 (Reference

[14]). Where MF is a margin factor, and Lla is the crack extension.

C 1 , C 2 , C 3 , and C 4 are coefficients which depend on the crack tip temperature and the Charpy V-notch upper-shelf energy as defined below: C 1 = exp(-2.44

+ 1.13 ln(CVN) -0.00277T)

C 2 = 0.077 + 0.116 ln C 1 C 3 = -0.0812 -0.0092 ln C 1 C 4 = -0.409 Where CVN is the Charpy V-notch upper-shelf energy in ft-lbs, and Tis the crack tip temperature in °F. In this analysis the margin factor, MF, is taken as [ ] for all cases, which provides a conservative J-R curve as required by Reference

[3]. Section 3.3.1 of Reference

[14] states that the use of this model should be justified if the sulfur content of the plate is greater than 0.018 wt%. Per Reference

[10] ( [ ] ), the nozzle N-16D is located in [ ] which is comprised of plates [ ] . These Page 22 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary plates each have [ model is applicable.

] per Reference

[10] ( [ ] ). Therefore, the use of this An additional input for the J-R model is the Charpy upper shelf energy (USE), which is provided in Reference

[1 OJ ( [ ] ) at this location as follows: Initial Longitudinal USE = [ ] Initial Transverse USE = [ ] [ ] EFPY Transverse USE = [ l Per the discussion in the Reg. Guide 1.161 (Reference

[ 14 ]), CVN value used in the J-R model should be for the proper orientation, which is longitudinal for axial flaws and transverse for circumferential flaws. Since hoop stresses are higher than axial stresses, an axial flaw is the preferred orientation for cracking, and this analysis applies the higher hoop stresses.

Based on the same [ ] applied to the transverse USE, the [ ] EFPY longitudinal USE would be approximately

[ ] . In this report, the results will be shown using both the bounding transverse USE of [ ] and the more pertinent longitudinal USE of [ l . The resulting material J-R curves is plotted for several temperatures in Figure 4-1 and Figure 4-2 using USE of [ ] and [ ] , respectively.

Figure 4-1: J-R Curves as a Function of Temperature (USE= [ l ) Page 23

A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Figure 4-2: J-R Curves as a Function of Temperature (USE= [ ] ) The material tearing modulus is calculated using the following equation Tmat = (~) a~at Where Eis the Elastic Modulus, a 1 is the flow stress defined as 0.5(ay + aJ, and the derivative of the J-R curve is a~:at = MF{C1C2(Lla)C 2-1 + C1C3C4(Lla)c 2+Cr 1}exp(C3(Lla)C

4) 4.3 Transients The analysis in Appendix A makes use of detailed pressure and thermal time history input to derive the applicable transient stresses that constitute the operational stresses contributing to the crack driving forces used in the current fracture mechanics analysis.

Stresses are transferred from the elastic plastic finite element stress model in Appendix A in the form of nodal arrays contained in ANSYS parameter files (Table 4-8). The applicable transients analyzed in Appendix A are summarized in Table 4-7: Page 24 n AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 4-7: Operating Transients and Cycles Condition Transient File Name Number of Convention Cycles [ [ l [ A/B ] ] [ ] [ ] [ ] (I) C NAC 2 l [ ] [ ] D [ ] [ ] NA<2 l Note (1): [ ] Note (2): Per A-5200 of ASME Section XI (Reference

[2]), cumulative fatigue crack growth analysis of components need not include emergency and faulted conditions.

4.4 Finite

Element Model The finite element model utilized is a three-dimensional quarter symmetry model. The model is meshed using ANSYS element types SOLID186 and SOLID 187. The crack tip elements are SOLID186 elements collapsed into wedges with the appropriate mid-side nodes moved to the quarter points to simulate the singularity at the crack tip. Two base geometries and meshes are generated in the input files "Base_model.inp" (crack fronts 1, 2, and 3) and "Base_ model_ 4. inp" ( crack front 4) and the explicit crack models are then created by replacing the appropriate brick elements with crack tip elements using the file "gen_crack_models.inp".

4.4.1 Boundary

Conditions The displacements are constrained normal to the face of the symmetry planes and the additional model cutting plane. The displacements of the nodes on the crack face are not constrained.

4.4.2 Applied

Stresses Applied stresses are due to residual stresses and operating stresses.

A three-dimensional elastic plastic finite element stress analysis of the applicable operating transients is performed in Appendix A. The analysis in Appendix A makes use of detailed pressure and thermal time history input to derive the applicable transient stresses that constitute the operational stresses contributing to the crack driving forces used in the current fracture mechanics analysis.

The combined residual plus operating stresses are obtained by utilizing the model developed by the WRS analysis (Reference

[15]). Residual stresses only and steady state normal operating stresses are also extracted in Appendix A. Stresses are mapped to the crack face from the elastic plastic finite element stress model to the finite element crack model through arrays of nodal locations and hoop stresses documented in Appendix A. The operating pressure is also applied to the crack face to account for the additional loading. Figure 4-3 shows an example of the weld residual stresses mapped onto crack face 1. The files used for stress results are listed in Table 4-8. Page 25 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 4-8: Stress Result Files Load Stress File [ ] [ ] .out [ ] [ ] .out [ ] [ ] .out [ ] [ ] .out Normal Operating Steady State NO_Only.out Weld Residual Stress WRS _Only.out Figure 4-3: Weld Residual Stress Mapped to Crack Front 1 (psi) Page 26 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

5.0 COMPUTER

FILES 5.1 Hardware / Software ANSYS Version 16.0 (Reference

[16]) was used in this analysis, both in the main body and in Appendix A. Use of this version of ANSYS is acceptable since error notices were reviewed and none was found applicable to this analysis.

The installation verification results are found to be acceptable.

The installation verification files can be found under the following directories for each computing node used: ' ... \32-9277252-000\official\

Verification'

' ... \32-9 2 77252-000\official\Appendix

_A\ Verification' The hardware platform:

Intel(R) Xeon(R) CPU ES-2680 0@ 2.70GHz; 49 GB RAM; Operating system: Red Hat Enterprise Server v6.4, kernel: 2.6.32-358.el6.x86_64.

The computer used for this analysis is a multi-node server (auslynchpci04), the computing node used to run this analysis was determined by queuing software.

The verification runs were submitted in the same queue as the analysis reported in the main body and in Appendix A of this document.

The queue was initiated by L. Matte (preparer of revision 000). Test runs rendered acceptable results. 5.2 Computer Files The computer files for runs performed in revision 000 are listed in Table 5-1. Files are stored in ColdStor at the following directory:

'\cold\ General-Access\32\32-9000000\32-92 77252-000\official' Table 5-1: Computer Files CRC Checksum Size (Bytes) Modified Date Time File Name . ./01 Model: 43247 22346307 Oct 24 2017 8:45:32 Base __ _model. inp 44896 6655 Mar 9 2017 10:15:21 Crack Fam\ fesh2. mac 50785 11715 Oct 24 2017 9:17:30 gen ___ crack._models.

inp 61270 927979 Oct 24 2017 9:29:47 gen __ .. crack _models.out 32623 8404 Oct 3 2017 11:02:15 materials.inp . ./01 Model/Crack 4: 30559 17316219 Oct 24 2017 19:26:47 Bose _model_ 4. inp 44896 6655 Mar 9 2017 10:15:21 CrockFanMesh2.

mac 53386 11812 Oct 24 2017 16:26:00 gen ... crack __ models. inp 20516 876845 Oct 24 2017 19:30:20 <'en crack models.out 0 ...... ,. ... 32623 8404 Oct 3 2017 11:02:15 materials.

inp . ./02 KI Transient:

20608 3153 Dec 6 2017 15:59:47 08912 3153 Dec 6 2017 21:43:51 50821 3153 Dec 7 2017 3:29:39 38826 3153 Dec 7 2017 7:13:29 05783 5206 Oct 11 2017 12:47:16 Get SJ F mac Page 27 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary CRC Checksum Size (Bytes) Modified Date Time File Name 14287 11553 Dec 6 2017 13:22:08 54058 11553 Dec 6 2017 19:08:15 12084 11553 Dec 7 2017 0:41:44 61809 11553 Dec 7 2017 5:29:23 25690 4833 Dec 6 2017 15:31:14 04886 4833 Dec 6 2017 21:14:22 35776 4833 Dec 7 2017 2:55:09 42984 4833 Dec 7 2017 6:54:37 05467 5553 Dec 6 2017 14:34:00 29157 5553 Dec 6 2017 20:16:50 13773 5553 Dec 7 2017 1:54:05 63916 5553 Dec 7 2017 6:15:53 47807 4017 Oct 8 2017 14:51:38 SJF Driver.mac 54740 510 Dec 5 2017 13:38:34 SJF __ calc.inp 23106 24787706 Dec 7 2017 7:13:30 SJF calc.out 01545 10916 Oct 6 2017 17:13:14 Tr __ Definp 52017 844 Oct 24 2017 9:24:29 calc k.mac . ./03 KI WRS: 61673 5113 Oct 11 2017 13:41:41 Get SJ F mac 52446 3856 Oct 10 2017 18:02:25 SlF Driver /FRS.mac -*--**-03661 528 Dec 5 2017 13:45:03 SIF_calc.inp 57172 598472 Dec 5 2017 20:57:23 SlF ca/c.out 13411 1953 Dec 5 2017 20:40:44 WRS __ hoop I a. Kl 23441 1953 Dec 5 2017 20:46:53 WRS __ hoop2a.K/

53878 1953 Dec 5 2017 20:53:16 FVRS_hoop3a.

Kl 39502 1953 Dec 5 2017 20:57:22 WRS_lwop4a.K/

52017 844 Oct 24 2017 9:24:29 calc k.mac . ./04 KI NO: 48377 5117 Oct 11 2017 17:31:50 Gt:t S!Fmac 33380 1953 Dec 5 2017 21 :03 :14 NO ___ hoop I a. Kl 32988 1953 Dec 5 2017 21:09:24 NOhoop2a.FJ 44242 1953 Dec 5 2017 21:15:52 NOhoop3a.KI 36829 1953 Dec 5 2017 21:20:03 NO_hoop../a.

Kl 31067 3854 Oct 11 2017 17:28:14 SIF Driver /VO.mac 26706 526 Dec 5 2017 13:46:03 SJ F~_calc. inp 02181 598420 Dec 5 2017 21:20:04 SIF calc.out 52017 844 Oct 24 2017 9:24:29 ca/c k.mac . ./05 LimitLoad:

40133 9220701 Oct 25 2017 10:18:51 Base ___ model __ LL. inp 04643 2208 Dec 5 2017 14:13:51 Um2PRf'.5'_LL.inp 22931 179303 Dec 12 2017 17:54:11 Lim:! PRV.5 !Lout ***--34628 4732 Dec 12 2017 16:57:20 materia!s

__ LL. inp . .IS readsheets:

28515 136129 Dec 12 2017 20:47:38 56034 136362 Dec 12 2017 20:47:33 44053 65035 Dec 7 2017 10:56:49 23805 64977 Dec 7 2017 10:24:09 01396 552284 Dec 12 2017 20:47:47 LEFi\,f FCG.xlsm Page 28 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary CRC Checksum Size (Bytes) Modified Date Time File Name .. N erification/ausl:ynchpc32/:

41657 99775 Dec 12 2017 17:05:34 vm143.out 14990 746 Dec 12 2017 17:05:34 vm1./J. vrt .. N erification/ausl:ynchpc33/:

59543 99107 Dec 5 2017 20:34:57 vml4J.011t 14990 746 Dec 5 2017 20:34:57 vm/43.vrt

.. N erification/ausl:ynchpc34/:

28220 99107 Oct 11 2017 11:03:23 vml43.out 14990 746 Oct 11 2017 11:03:23 vm/43.\'l't

.. N erification/ausl:ynchpc35/:

47010 99107 Oct 11 2017 15:45:02 vm/43.out 14990 746 Oct 11 2017 15:45:02 vml./3.vrt

.. N erification/ausl:ynchpc36/:

13470 99107 Oct 24 2017 19:29:53 vm 1./3. out 14990 746 Oct 24 2017 19:29:53 vm/43.vrt . ./ Appendix A: . ./A endix A/ThermalAnal sis: 61443 25770 Oct 4 2017 10:39:58 49280 31789 Oct 4 2017 10:40:00 14392 38929 Oct 4 2017 10:39:59 09396 51386 Oct 4 2017 10:39:56 31088 13563 Oct 3 2017 20:07:57 ierma!Tra11sients.

inp 16336 845326 Oct 3 2017 21:36:35 Thenna!Transients.

out 43173 4344 Oct 4 2017 10:16:43 dTpost Processing.

mac . ./A endix A/StructuralAnal sis: 46314 14061 Oct 4 2017 12:14:52 38960 24895 Dec 5 2017 18:04:17 38901 14074 Dec 5 2017 13:07:04 32677 24882 Dec 5 2017 17:05:02 42955 1858 Dec 5 2017 13:02:20 Stress_ OpCond ilzp 24836 11089 Dec 5 2017 13'43 ,55 c*ess _ Op('ond a,,; J 13499 14068 Oct 4 2017 12:11:01 20849 24911 Dec 5 2017 17:31:14 25465 14089 Oct 4 2017 12:13:04 61713 24971 Dec 5 2017 17:52:41 . ./ Appendix A/PostProcessing:

52532 1491679 Dec 5 2017 18:06:25 [ ] 44551 8933581 Dec 5 2017 18:05:25 [ ] 04287 428359 Dec 5 2017 18,04,20 [_Only.on/

J 49986 4793 Dec 5 2017 13:11:24 65322 25777 Dec 5 2017 18:06:25 64740 4796 Dec 5 2017 13:11:13 Page 29 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary CRC Checksum Size (Bytes) Modified Date Time File Name 50109 25862 Dec 5 2017 18:05:26 [ ] 31438 4245 Dec 5 2017 13:11:06 PostProcssingNO.

inp 44602 24760 Dec 5 2017 18:04:20 PostProcssingNO.out 01873 4796 Dec 5 2017 13,11,17[ . J 01600 25813 Dec 5 2017 18:05:53 21607 4805 Dec 5 2017 13:11:21 08622 25917 Dec 5 2017 18:06: 14 58856 4209 Dec 5 2017 13:11:03 PostProcssinglFRS.inp 31567 24751 Dec 5 2017 18:04:24 Post Procssi ng WRS. out 61854 3617953 Dec 5 2017 18:05:52 [ ] 62251 2980153 Dec 5 2017 18:06:14 [ ] 41149 428383 Dec 5 2017 18:04:24 /FRS _Onzv. out . ./ AQQendix AN erification/auslynchQc24:

35131 55394 Oct 3 2017 21:07:52 vm32mod2 D. 011! 48891 606 Oct 3 2017 21:07:52 vm32mod2D.

vrt 05951 110066 Oct 3 2017 21:07:54 vm32nwd3 D. out 34040 606 Oct 3 2017 21:07:54 vm32mod3D.

vrt 38558 15060 Oct 3 2017 21:07:53 vm38mod]D.

out 20215 632 Oct 3 2017 21:07:53 vm38mod2D.

vrt 10772 17521 Oct 3 2017 21:07:55 vm38mod3D.out 09779 632 Oct 3 2017 21:07:55 vm38mod3D.

vrt .. / AQQendix AN erification/auslynchQc32:

64980 55395 Oct 11 2017 17:33:11 vm32mod2 D. out 48891 606 Oct 11 2017 17:33:11 vm32mod2D.

vrt 63496 110067 Oct 11 2017 17:33:13 vm32mod3 D. out 34040 606 Oct 11 2017 17:33:13 vm32mod3D.

vrt 25032 15061 Oct 11 2017 17:33:12 vm38mod2 D. out 20215 632 Oct 11 2017 17:33:12 vm38mod2D.

vrt 54259 17491 Oct 11 2017 17:33:14 vm38mod3 D. out 09779 632 Oct 11 2017 17:33:14 vm38mod3D.

vrt .. / AQQendix AN erification/auslynchQc33:

43546 56063 Dec 5 2017 13:29:18 vm32mod2D.

out 48891 606 Dec 5 2017 13:29:18 vm32mod2 D. vrt 8182 110067 Dec 5 2017 13:29:20 vm32mod3D.out 34040 606 Dec 5 2017 13:29:20 vm32mod3 D. vrt 21193 15061 Dec 5 2017 13:29:19 vm38mod2 D. out 20215 632 Dec 5 2017 13:29:19 vm38mod2D.

vrt 55669 17491 Dec 5 2017 13:29:22 vm38mod3D.

out 9779 632 Dec 5 2017 13:29:22 vm38mod3D.

vrt . ./ AQQendix AN erification/auslynchQc34:

48664 55395 Oct 6 2017 14:43:16 vm32mod2J).

vrt 48891 606 Oct 6 2017 14:43:16 l'ln32mod3D.

out 33726 110067 Oct 6 2017 14:43:18 vm32mod3D.

vrt 34040 606 Oct 6 2017 14:43:18 l'm38mod2 D. out 43215 15061 Oct 6 2017 14:43:17 vm38mod2D.

vrt 20215 632 Oct 6 2017 14:43:17 vm38mod3 D. out 22549 17491 Oct 6 2017 14:43:19 vm38mod3D.

vrt Page 30 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary CRC Checksum Size (Bytes) Modified Date Time File Name 09779 632 Oct 6 2017 14:43:19 vm32mod2D.

i*rt . ./ Appendix A/V erification/auslynchpc35:

02692 55395 Oct 4 2017 9:45:04 vmJ2mod2D.

vrt 48891 606 Oct 4 2017 9:45:04 1*11132mod3 D. out 45768 110067 Oct 4 2017 9:45:07 vm32mod3D.

vrt 34040 606 Oct 4 2017 9:45:07 l'm38mod2 D. out 40378 15061 Oct 4 2017 9:45:05 vm38mod2D.

vrt 20215 632 Oct 4 2017 9:45:05 l'm38mod3 D. out 62927 17491 Oct 4 2017 9:45:08 vm38mod3D.

vrt 09779 632 Oct 4 2017 9:45:08 l'm32mod2D.vrt

.. / Appendix A/V erification/auslynchpc36:

50376 55395 Oct 4 2017 14:05:11 vm32mod2D.

vrt 48891 606 Oct 4 2017 14:05:11 vm32mod3D.out 46458 110067 Oct 4 2017 14:05:13 vm32mod3D.

vrt 34040 606 Oct 4 2017 14:05:13 vm38mod2D.

out 47974 15061 Oct 4 2017 14:05:12 vm38mod2D.

vn 20215 632 Oct 4 2017 14:05:12 vm38mod3 D. out 21556 17491 Oct 4 2017 14:05:14 vm38mod3D.

vrt 09779 632 Oct 4 2017 14:05:14 1*11132mod2 D. vrt Page 31 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

6.0 CALCULATIONS

6.1 Stress

Intensity Factors SIFs are calculated for each postulated crack front using the stress results from the files listed in Table 4-8. The calculations are run by the ANSYS input file "SIF_calc.inp" (see Table 5-1). The ANSYS macro "SIF_Driver.mac" sets the crack face boundary conditions, reads in data from the stress models, and sets up data arrays. The file "Get_SIF.mac" is used to perform stress mapping, solve the model with mapped stresses and then calculate the SIFs (using "calc_k.mac").

The SIF calculation results are written to the "*.KI output files (see Table 5-1 ), which contain the SIFs for each step of a transient.

6.2 Crack

Growth Utilizing the SIF solutions described in Section 6.1, fatigue crack growth is calculated.

The fatigue crack growth rule in Section 2.2 is integrated numerically using, The impact of the cycle increment

(~N) was investigated, and it was found that utilizing the number of cycles per week for the first year and on a per year basis for the remaining years was a sufficiently small increment to accurately integrate the crack growth. Therefore, crack growth presented in this report has been calculated on a per week or per year basis. Crack growth is evaluated for [ ] years of operation.

Based on the reviews of the results, the stress intensity factors at position [ ] is found to be the bounding location and chosen for detailed evaluation.

Fatigue crack growth calculations for position [ ] are performed in the spreadsheet "LEFM_FCG.xlsm" (see Table 5-1), and the detailed results are shown in Appendix B. Stress corrosion crack growth is calculated using a constant crack growth rate as described in Section 2.3 and detailed results are shown in Table B-7. The final flaw size includes fatigue crack growth from all applicable transients and sec crack growth. 6.3 LEFM Evaluation LEFM evaluation is performed for the final flaw size from the crack growth evaluation.

The applied SIF is evaluated accounting for the plastic zone correction described in Section 2.1.1, and its acceptability is evaluated based on the rules outlined in Section 2.4. The results for the bounding crack tip position [ ] are shown in Table 6-1. Page 32 L AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 6-1: LEFM Results -Crack Tip Position [ ] --RTNDT Tc Upper ShelfTou2hness Initial Flaw Size, a; Final Flaw Size, ar Crack Growth, ..aa = ar-a; --Loading<*>

[ ] [ ] [ ] [ ] [ ] (cold) Service Level AIB A/B C D A/B Step Fluid Temperature

{°Fi 2> Pressure (psi) O"y (ksi) Kie (ksi ...Jin) K(a) (ksi ...Jin) lle (in) K(aJ (ksi ...Jin) Margin =K 1 ,IK(aJ -1.41 (3) --Required Margin 3.16 3.16 1.41 1.41 Acceptable By LEFM? No No Yes Yes Yes Meets Tc Criterion for EPFM? Yes Yes Yes Yes NA Note (1): LEFM evaluation is reported for the limiting load step cases of each transient.

Additionally, a case where the fluid temperature is less than Tc is also reported for the [ ] transient.

Note (2): The transient fluid temperature at the limiting load step is selected for each transient.

Note (3): Pressure at cold load step does not exceed 20% of the design pressure; therefore acceptance criterion from IWB-3613(a) of Section XI (Reference

[2]) applies. Review of Table 6-1 results indicates that LEFM acceptance criteria are met except for the [ ] and [ ] transients after [ ] years of crack growth. All cases are shown to have temperature exceeding Tc = 154.8°F + 0.82 x RT NDT = [ ] and may therefore be analyzed based on EPFM. 6.4 EPFM Evaluations For the postulated crack, the EPFM evaluations will be performed for the final flaw size in accordance with the methodology described in Section 2.5 using the spreadsheets "EPFM-RG1161-

[ ] .xlsm" and RG1161-[ ] .xlsm" (see Table 5-1). As noted in Section 2.5, these evaluations conservatively include the weld residual stress, which is not required by Code Case N-749 (Reference

[3]). Page 33 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary As discussed in the previous section, only the [ ] and [ ] transients need to be evaluated using EPFM. However, for completeness, all transients will be evaluated using EPFM. Table 6-2 and Table 6-3 provide the results of the EPFM evaluations for the final flaw size using USE of [ ] and [ ] , respectively.

The [ ] USE results are applicable for the axial flaw. The [ ] USE results are included to conservatively demonstrate that a circumferential flaw, which has lower applied stresses (axial vs. hoop) but also lower toughness, is bounded by this analysis.

Note that when the higher safety factors provided in Section 3.1 of Code Case N-749 (Reference

[3]) are used for the applied J-Integral criterion the stability check is not required; however, it is included here for completeness.

For the postulated crack, as shown in Table 6-2 and Table 6-3, all cases meet the EPFM acceptance criteria after [ ] years of crack growth. Details of the calculations for the limiting [ ] transient are provided in Appendix B. In the EPFM evaluations, the K due to pressure (KIP) is calculated based on the steady state normal operating condition results (Table B-2). The steady state condition K is interpolated or extrapolated for the desired flaw size (see Section 2.1) and multiplied by the ratio of the transient pressure to the steady state normal operating pressure.

Table 6-2: EPFM Results -Crack Tip Position [ ] (USE= [ ] ) Loading [ ] [ ] [ ] [ ] Service Level AIB AIB C D Temperature

(°FPl Pressure (psi) Applied Primary Safety Factor 1.50 1.50 1.50 1.50 I-Integral Secondary Safety Factor 1.00 1.00 1.00 1.00 Check Iaor, (kips/in)

Jo.1 (kips/in)

Margin= Jo.ilfavv Required Margins ,--1.0 1.0 -1.0 1.0 Applied I-Integral Check Acceptable?

Yes Yes Yes Yes Stability Check Required?

Yes Yes No No Stability Primary Safety Factor 2.14 2.14 1.2 1.2 Check Secondary Safety Factor 1.00 1.00 1.00 1.00 Tann Tillstabilitv Margin = T;,.,,abuu/Tavv Required Margins 1.0 1.0 1.0 1.0 Stability Check Acceptable?

Yes Yes Yes Yes Note (1): The maximum transient fluid temperature, which minimizes J 0.1 , is conservatively selected for all transients.

Page 34 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 6-3: EPFM Results -Crack Tip Position [ ] (USE= [ ] ) Loading [ ] [ ] [ ] [ ] Service Level A/B A/B C D Temperature

(°F)<1> Pressure (psi) Applied Primary Safety Factor -2.00 2.00 1.50 1.50 J-Integral Secondary Safety Factor 1.00 1.00 1.00 1.00 Check Jann (kips/in)

Jo.1 (kips/in)

Margin= Jo.ii Jann ReQuired Margins -1.0 1.0 1.0 1.0 -APPiied J-Integral Check Acceptable?

Yes Yes Yes Yes Stability Check ReQuired?

No No No No Stability Primary Safety Factor 2.14 2.14 1.2 1.2 Check Secondary Safety Factor 1.00 1.00 1.00 1.00 Tann Tinstabilitv Margin = T;,,s1abiut/Taoo ReQuired Margins 1.0 1.0 1.0 1.0 Stabilitv Check Acceptable?

Yes Yes Yes Yes Note (1): The maximum transient fluid temperature, which minimizes J 0_1, is conservatively selected for all transients.

6.5 Primary

Stress Evaluation

6.5.1 Limit

Load Finite Element Model The acceptance criterion of items 3.l(c) and 3.2(a)(3) of Reference

[3] require that the primary stress limits of NB-3000 (Reference

[17]) are met assuming a local area reduction of the pressure retaining membrane that is equal to the area of the flaw. As described in Section 2.6, the primary stress limits for design conditions (NB-3221.1, NB-3221.2, and NB-3221.3) need not be satisfied if it can be shown by performing a limit analysis (NB-3228.1) that the applied loadings do not exceed two-thirds of the lower bound collapse load. This condition is equivalent to showing that the structure does not collapse at a pressure equal to 150% of the Design Pressure ( [ ] ). In terms of finite element results plastic collapse of the structure is equivalent to numerical instability.

The cladding, the [ ] weld material, [ ] nozzle, and portions of the RV material are removed in order to represent the material removed by the postulated J-Groove flaws and the crack growth. The removed material represents a crack growth of [ ] from the initial postulated flaw, which is slightly larger than the final flaw size calculated in Section 6.3. The resulting model geometry with material removed is shown in Figure 6-1. Page 35 ---

A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Figure 6-1: Limit Load Model Geometry The overall model geometry and mesh are defined in the input file "Base_ model_ LL. inp" (see Table 5-1 ). [ ] The finite element mesh utilized is shown in Figure 6-2. Page 36 A A.REV.A Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Figure 6-2: Limit Load Model Finite Element Mesh The material properties for the analysis are defined in the file "materials_LL.inp".

Note that the cladding and the [ ] weld material are excluded from the model since structural credit cannot be taken for the cladding and the [ ] weld material is postulated to be flawed. The properties are identical to those used in the explicit crack models with the exception that the material has been changed to be elastic-perfectly plastic. The value of yield strength used is based on Sm (Table 4-3 and Table 4-6) the Design Temperature of [ ] , Reference

[10] and is given below. [ [ ] ] Sy= l.5Sm = 1.5 X [ Sy = l.5Sm = 1.5 X [ ] = [ ] [ ] ] Pressure is applied to the ID surfaces of the vessel and replacement nozzle and to the original nozzle bore, incrementally increasing in each load step. Displacements normal to two planes of symmetry and the cut face in the model are constrained.

Additionally, end cap pressures are added to the end surfaces of the replacement nozzle and the RV. The analysis is run using the input file "Lim2_PRVS_LL.inp" with results output to "Lim2_PRVS_LL.out".

The analysis was run up to a pressure of [ ] which is equal to [ ] times the Design Pressure, which Page 37 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary exceeds the requirement of 150% of the Design Pressure.

The equivalent stress at the last load step is shown in Figure 6-3. Figure 6-3: Equivalent Stresses at the Final Load Step (psi) Page 38 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

7.0 CONCLUSION

S A fatigue and SCC crack growth and fracture mechanics evaluation of the postulated flaw in the as-left J-Groove weld and buttering has been performed.

Based on a combination of linear elastic and elastic-plastic fracture mechanics the postulated flaw is shown to be acceptable for 40 years of operation utilizing the safety factors in Table 1-1, and the applicable J-R Curves from Regulatory Guide 1.161 [14]. For temperatures below the upper shelf temperature the LEFM analysis based on IWB-3610 (Reference

[2]) criteria is applicable and the limiting case is summarized below from Table 6-1: Transient Service Level Temperature

(°F) Pressure (psi) K1c (ksi "1in) K(ae) (ksi "1in) Margin,K 1/K(a.J Required Margin Acceptable By LEFM? 1.41 Yes For temperatures above the upper shelf temperature the EPFM analysis based on Code Case N-749 (Reference

[3]) criteria is applicable and the limiting case is summarized below from Table 6-2 and Table 6-3: Transient

[ ] Service Level AIB Temperature

(°F) [ J Pressure (psi) USE (ft-lbs) A lied J-Inte ral Check Japp (kips/in)

J 0.1 (kips/in)

Margin = Jo./ Japp Required Margins 1.0 1.0 Applied J-Integral Check Acceptable?

Yes Yes Stability Check Required?

Yes No Stabili Check I.OJ Tapp T;nstabi/ity Margin = T;,,s,ab;u,/Tapp Required Margins 1.0 Stability Check Acceptable?

Yes Yes The primary stress criteria of IWB-3610(d)(2) of Reference

[2] and 3.l(c) and 3.2(a)(3) of Reference

[3] are satisfied since the limit analysis performed in Section 6.5 shows that the structure does not collapse at a pressure equal to 150% of the Design Pressure.

Page 39 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

8.0 REFERENCES

References identified with an (*) are maintained within Exelon Records System and are not retrievable from AREVA Records Management.

These are acceptable references per AREVA Administrative Procedure 0402-01, Attachment

8. See page 2 for Project Manager Approval of customer references.

1. [ ] 2. ASME Boiler and Pressure Vessel Code,Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components", 2007 Edition including Addenda through 2008 3. Cases of the ASME Boiler and Pressure Vessel Code, Case N-749, "Alternative Acceptance Criteria for Flaws in Ferritic Steel Components Operating in the Upper Shelf Temperature Range,"Section XI, Division l 4. [ ] 5. T.L. Anderson, "Fracture Mechanics

-Fundamentals and Applications", CRC Press, 1991. 6. [ ] 7. [ ] 8. Federal Register, Volume 81, Page 10787 (81 FR 10787), Wednesday March 2, 2016, Proposed Rules. 9. [ ] 10. [ ] 11. [ ] 12. ASME Boiler and Pressure Vessel Code,Section II, Part D "Properties (Customary)

Materials", 2007 Edition including Addenda through 2008 13. [ ] 14. Regulatory Guide 1.161, "Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less than 50 ft-lb", June 1995 15. [ ] 16. ANSYS Finite Element Computer Code, Version 16.0, ANSYS Inc., Canonsburg, PA 17. ASME Boiler and Pressure Vessel Code,Section III, "Rules for Construction of Nuclear Facility Components", Division 1, 2007 Edition including Addenda through 2008 Page 40 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary APPENDIX A: OPERATING STRESS ANALYSIS A.1 Purpose The purpose of Appendix A is to describe the development of the thermal and structural transient analysis for key operating transients and the extraction of stresses to support the fracture mechanics analysis presented in the main body of this document.

A.2 Methodology The methodology consists of the following:

1. Obtain the FE models developed by the WRS analysis (Reference

[15]). The final simulation provided by the WRS analysis is the welding of the new J-Groove weld to the new replacement nozzle and weld pad. There are two models with identical mesh: one for the thermal analysis " [ ] " and one for the structural analysis " [ ] " (Reference

[ 15]). 2. Obtain the bounding key operating transients defined in one cycle justification J-Groove weld analysis, Reference

[4]. Reference

[4] reviews the transients defined in [ ] of Reference

[10] and selects the bounding transients based on pressure and temperature ranges. 3. Apply the temperature and heat transfer coefficient of applicable transients for normal, upset, emergency and faulted conditions on the thermal FE model. 4. Define the locations of interest for thermal gradients within the model, obtaining values of thermal gradients for the entire transient from runs on the thermal model, and selecting the time points for structural runs. 5. Simulate three steady state operating conditions cycles after the welding of the new J-Groove weld by applying the corresponding temperature and pressure as a static load step. Each steady state cycle includes going from ambient conditions (zero pressure and room temperature) to operational pressure and temperature then going back to ambient conditions.

6. Apply pressure and temperature on the structural model for the time points identified in step 4 to obtain stresses resulting from pressure and thermal gradients.

The sequence of each applicable transient is defined as follows: a. Three cycles of the [ ] are performed at the end of step 5 followed by one cycle of steady state operating condition.

b. One cycle for each remaining applicable transients is performed at the end of step 6a above. 7. The combined residual plus operating hoop stresses applicable for evaluating a postulated remnant flaw in the as-left J-groove weld are extracted along the nodes on the symmetry plane that slices the RV shell in the vertical direction, referred to as the "0-Degree" plane for ease ofreference.

A.3 Assumptions and Modeling Simplifications

1. There are no unverified assumptions used within this appendix.

Justified assumptions and modeling simplifications are detailed as follows. 2. Since the FE models used in this appendix are from Reference

[15], the same assumptions and modelling simplifications listed in Section 3.0 of Reference

[15] are also applicable to this appendix.

Page A-1 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary

3. Heat transfer coefficient inside nozzle is set to [ ] and to [ ] on insulated surfaces of the nozzle and RV shell. These values are based on experience with modeling similar geometries and are considered appropriate for this configuration.

A.4 Design Inputs The geometry details, finite element model description, and material designations of the FE models utilized in this appendix are listed in Sections 4.0 of Reference

[15]. A.4.1 Transient Definitions The bounding transients selected in Reference

[ 4] are listed as follows: The [ ] transient described in Table A-1 and Figure A-1 refers to [ ] on Reference

[10]. This transient is part of Normal and Upset Conditions.

The [ ] transient described in Table A-2 and Figure A-2 refers to [ ] on Reference

[10]. This transient is part of Normal and Upset Conditions.

The [ The [ ] transient described in Table A-3 and Figure A-3 refers to [ ] on Reference

[10]. This transient is an Emergency Condition.

] transient described in Table A-4 and Figure A-4 refers to [ ] on Reference

[10]. This transient is a Faulted Condition.

A heat transfer coefficient of [ calculated using equation:

[ ] is used on the RV shell inner surface. This value is ] (reference

[10], [ ] ); where the [ ] (reference

[1 O], [ ] ). Values of heat transfer coefficient of [ ] at the nozzle inner surface, and [ ] for the insulated condition on the model outer surfaces are considered appropriate in this location (see Section A.3). In accordance with Reference

[10], the following changes due to [ ] are incorporated:

1. Operating temperatures are [ ] . 2. Operating pressure is [ ] . 3. In the [ ] events, [ ] . Page A-2

~

A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table A-1: [ ] Time Temperature Pressure Time Temperature Pressure [sec] [OF] [psig] [sec] [OF] [psig] ----Figure A-1: [ ] Page A-3 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table A-2: [ ] Time Temperature Pressure .. -[sec] [OF] [psig] __ --Figure A-2: [ ] Page A-4 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table A-3: [ ] Time Temperature Pressure [sec] [°F] [psig] Figure A-3: [ ] Page A-5 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table A-4: [ ] Time Temperature Pressure [sec] [°F] [psig] Figure A-4: [ ] A.5 Calculations A.5.1 Thermal Analysis The temperatures listed in Table A-1 through Table A-4 were applied on all wetted surfaces.

The outer surfaces of the replacement nozzle and the part of original nozzle inserted into the RV were thermally coupled with inner surface of the opening bore. Input data for transient thermal analyses are listed in Section A.4.1. The thermal run is documented in computer output file 'Therma!Transients.out' (see Table 5-1 ). A.5.2 Structural Analysis The time-points for structural runs were selected based on the pressure transients (listed in Table A-1 through Table A-4) and thermal gradients (temperature differences) between two locations of interest on the J-Groove weld and original nozzle. The approximate location for thermal gradients can be found on Figure A-5. The thermal gradient listing can be found in computer files '*_dT.out' (see Table 5-1). PageA-6 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary A list of time-points for which the structural runs were submitted can be found in Table A-5. The pressure was applied on all wetted surfaces, including outer surface of original nozzle and inner surface of shell hole. The displacements are constrained normal to the face of the symmetry planes and the additional model cutting plane, the end cap pressure was applied for all structural runs on the end surface of the replacement nozzle and RV Shell. The body temperature corresponding to the time of the transient is applied to the structural model from result file from thermal transient analysis of Section A.5.1. The structural runs are documented in computer files 'Stress_ *.out' (see Table 5-1). Computer output file 'Stress_OpCond.out' (see Table 5-1) documents the first three steady state operating conditions cycles after the welding of the new J-Groove weld by applying the corresponding temperature and pressure as a static load step. Each steady state cycle includes going from ambient conditions (zero pressure and room temperature) to operational pressure and temperature then going back to ambient conditions.

Three cycles of the [ ] are performed after the last cycle of steady state operating condition described above. After the last cycle of [ ] , one cycle of steady state operating condition is also applied. One cycle for each remaining applicable transients is performed at the end of step [ ] run, starting at the steady state condition.

Figure A-5: Locations for Thermal Gradients Page A-7 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table A-5: Time Points Selected for Stress Run Page A-8 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary A.6 Results The stresses applicable for evaluating a postulated remnant flaw in the as-left J-groove weld are extracted along the nodes on the symmetry plane that slices the RV shell in the vertical direction will be referred to as the "0-Degree" plane for ease of reference.

The weld residual stresses applicable for evaluating a postulated remnant flaw in the as-left J-groove weld are extracted for all nodes located along the "0-Degree" plane. Residual hoop stresses are extracted for these nodes at cold shutdown state. The residual stresses are contained in file "WRS_Only.out" and the post processing is documented in file "PostProcssingWRS.out" (see Table 5-1). Also, the operating transient hoop stresses are extracted for all the nodes located on the "0-Degree" plane for all the time points discussed in Section A.5.2. The operating stresses for the [ ] transient are contained in file " [ ] .out" for which the post processing is documented in file "PostProcssing

[ ] .out" (see Table 5-1). The operating stresses for the [ ] . transient are contained in file "SCRM.out" for which the post processing is documented in file "PostProcssing

[ ] .out" (see Table 5-1). The operating stresses for the [ ] transient and [ ] transient are contained in files " [ ] .out" and " [ ] .out", respectively for which the post processing are documented in files "PostProcssing

[ ] .out" and "PostProcssing

[ ] .out" respectively (see Table 5-1). Additionally, the steady state stresses are extracted for all nodes located along the "0-Degree" plane. Hoop stresses are extracted for these nodes at steady state conditions.

The steady state stresses are contained in file "NO_ Only.out" and the post processing is documented in file "PostProcssingNO.

out" (see Table 5-1 ). Each results file contains arrays with the locations of the finite element model nodes on the 0-Degree" plane. The coordinates (X, Y and Z) are in the global Cartesian coordinate system. The nodal coordinates are defined in arrays ZDLOC and ZDONOZLoc at the "0-Degree" plane nodes where ZDONOZLoc is applicable for nodes on the original nozzle only and array ZDLOC is applicable to nodes elsewhere.

The hoop stresses are defined in the following arrays: ZDWRS_Hoop Weld residual stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle ZDONOZWRS_Hoop Weld residual stresses at "0-Degree" plane on nodes located at the original nozzle ZDNO _Hoop Steady State stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle ZDONOZNO_Hoop Steady State stresses at "0-Degree" plane on nodes located at the original nozzle ZD [ ] _Hoop [ ] stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle ZDONOZ [ ] _Hoop [ ] stresses at "0-Degree" plane on nodes located at the original nozzle ZD [ ] _Hoop [ ] stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle ZDONOZ [ ] _Hoop [ ] stresses at "0-Degree" plane on nodes located at the original nozzle ZD [ ] _Hoop [ ] stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle Page A-9 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary ZDONOZ [ ZD [ ZDONOZ [ ] [ ] stresses at "0-Degree" plane on nodes located at the original _ Hoop nozzle ] _Hoop [ ] stresses at "0-Degree" plane on all nodes except nodes located on the original nozzle ] _Hoop [ ] stresses at "0-Degree" plane on nodes located at the original nozzle Page A-10 ___J 0 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary APPENDIX B: FLAW EVALUATIONS This appendix presents the fatigue crack growth, SCC crack growth, and flaw evaluations for the postulated flaw. Table B-1: SIFs -Welding Residual Stress Crack Front I K (psi;/in) at Flaw Size (in) I Position 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 -

Cl A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 8-2: SIFs -Steady State Normal Operating Condition Crack Front l.. K (psi.../in) at Flaw Size (in) I Position 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 -Page B-2 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Table 8-3: SIFs -Emergency Transient

[ ] Crack Front Maximum K (psi-Vin) at Flaw Size (in) -Position 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 --Page B-3 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Table B-4: SIFs -Faulted Transient

[ ] Crack Front I Maximum K (psi"Yin) at Flaw Size (in) I Position 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 -Page B-4 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Table B-5: Fatigue Crack Growth for Transient

[ ] Page B-5 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 8-6: Fatigue Crack Growth for Transient

[ ] Page B-6 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Table B-7: Stress Corrosion Flaw Growth Page B-7 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 8-8: EPFM Evaluation for [ ] (USE= [ ] ) Page B-8 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-16D As-Left J-Groove Weld Analysis-Non-Proprietary Table 8-9: EPFM Evaluation for [ ] (USE= [ ] ) Page 8-9 A AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Figure B-1: J-T Diagram for [ ] (USE= [ ] ) Page B-10 AREVA Document No. 32-9281804-000 Limerick Unit 2 Instrumentation Nozzle N-160 As-Left J-Groove Weld Analysis-Non-Proprietary Figure B-2: J-T Diagram for [ ] (USE= [ l ) Page 8-11

ML18129A332

Text

SUMMARY

SUMMARY

7.0 CONCLUSION

8.0 REFERENCES

1.0 PURPOSE

2.0 ANALYTICAL

2.1 Stress

2.3 Stress

2.5.1 Screening

2.6 Primary

3.0 ASSUMPTIONS

3.1 Unverified

3.2 Justified

3.3 Modeling

4.0 DESIGN

4.2 Materials

4.2.1 Material

4.2.2 Mechanical

4.4 Finite

4.4.1 Boundary

4.4.2 Applied

5.0 COMPUTER

6.0 CALCULATIONS

6.1 Stress

6.2 Crack

6.5 Primary

6.5.1 Limit

7.0 CONCLUSION

8.0 REFERENCES

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