ML18129A333
| ML18129A333 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 05/04/2018 |
| From: | AREVA, Exelon Generation Co |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| LG-18-068 32-9277502-000 | |
| Download: ML18129A333 (30) | |
Text
Attachment 7 "Limerick Unit 2 Instrument Nozzle N-160 Repair Weld Residual Stress Analysis (Non-Proprietary)," AREVA Document No. 32-9277502-000, Non-Proprietary Version
0402-01-F01 (Rev. 020, 11/17/2016)
CALCULATION
SUMMARY
SHEET (CSS)
AREVA Document No. 32 Safety Related: ~Yes D No
-Limerick
-- - -29277502
-Unit - ----- 000 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Title Proprietary)
PURPOSE AND
SUMMARY
OF RESULTS:
The purpose of this report is to document the results of the weld residual stress finite element analysis of the Reactor Vessel (RV) instrument nozzle N-16D penetration as-left J-groove weld at Limerick Unit 2 Nuclear Power Plant. This analysis includes weld simulation of the original butter and J-groove weld (including the inner diameter overlay) attaching the remnant instrument nozzle to the reactor vessel shell. The analysis also includes simulation of the recent weld repair involving outer diameter weld pad and J-groove weld of the replacement nozzle. The state of stress at the end of final welding, as predicted by the ANSYS Version 16.0 finite element analysis, is summarized to support flaw evaluations of the as-left (original) J-groove weld. The ANSYS computer model files including residual stress results are available for use in the subsequent fracture mechanics analysis.
Rev 000: The proprietary version of this document is 32-9274303-001.
AREVA Inc. proprietary information in the document is indicated by pairs of braces "[ ]".
If the computer software used herein is not the latest version per the EASI list, THE DOCUMENT CONTAINS AP 0402-01 requires that justification be provided.
ASSUMPTIONS THAT SHALL BE THE FOLLOWING COMPUTER CODES HAVE BEEN USED IN THIS DOCUMENT: VERIFIED PRIOR TO USE CODENERSION/REV CODENERSION/REV DYes ANSYS 16.0 IZI No Page 1 of29
A 0402-01-F01 (Rev. 020, 11/17/2016)
Document No. 32-9277502-000
.AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Review Method: cg] Design Review (Detailed Check)
D Alternate Calculation Does this document establish design or technical requirements? D YES cg] NO Does this document contain Customer Required Format? DYES IZJ NO Signature Block P/R/A/M Name and Title and Pages/Sections (printed or typed) . Signature LP/LR Date Prepared/Reviewed/Approved p
~
Tom Riordan All Engineer IV 01ocrz.oq AshokDNana Supervisory Engineer ~
R 10/4 /1, All
~~~
David R Cofflin A All Engineering Manager 1¢/Yi<t-J Notes: P/R/A designates Preparer (P), Reviewer (R), Approver (A);
LP/LR designates Lead Preparer (LP), Lead Reviewer (LR);
M designates Mentor (M)
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 (NIA if not applicable)
Name Title (printed or typed) (printed or typed) Signature Date NIA Page2
0402-01-F01 (Rev. 020, 11/17/2016)
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Record of Revision Revision Pages/Sections/Paragraphs No. Changed Brief Description / Change Authorization 000 All Initial Release All The proprietary version of this document is 32-9274303-001.
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Table of Contents Page SIGNATURE BLOCK ................................................................................................................................ 2 RECORD OF REVISION .......................................................................................................................... 3 LIST OF TABLES ..................................................................................................................................... 5 LIST OF FIGURES ................................................................................................................................... 6
1.0 INTRODUCTION
........................................................................................................................... 7 2.0 ANALYTICAL METHODOLOGY ................................................................................................... 7 2.1 Welding Analysis Methodology ......................................................................................................... 8 3.0 ASSUMPTIONS .......................................................................................................................... 12 3.1 Unverified Assumptions ................................................................................................................... 12 3.2 Justified Assumptions ...................................................................................................................... 12 3.3 Modeling Simplifications .................................................................................................................. 12 4.0 DESIGN INPUTS ........................................................................................................................ 13 4.1 RV and N160 Nozzle Geometric Data ............................................................................................ 13 4.2 RV and N160 Nozzle Material Information ..................................................................................... 13 4.3 Welding Parameters ........................................................................................................................ 14 4.4 The Finite Element Model ............................................................................................................... 17 4.5 Boundary Conditions for Welding Simulation .................................................................................. 20 4.5.1 Thermal Analysis - Welding Simulation ........................................................................... 20 4.5.2 Structural Analysis - Welding Simulation .......................................................................... 20 5.0 RESULTS ......................................................................*.............................................................. 21 6.0 COMPUTER USAGE .................................................................................................................. 24 6.1 Hardware/ Software ........................................................................................................................24 6.2 Computer Files ................................................................................................................................24
7.0 REFERENCES
............................................................................................................................ 26 APPENDIX A: VERIFICATION OF ANSYS COMPUTER CODE ........................................................ 27 Page4
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
List of Tables Page Table 4-1: RV and Instrument Nozzle Dimensions ................................................................................ 13 Table 4-2: Component Material Designation ......................................................................................... 14 Table 4-3: Welding Parameters for Butter Weld .................................................................................... 15 Table 4-4: Welding Parameters for J-Groove Weld ............................................................................... 15 Table 4-5: Welding Parameters for the New (Repair) Weld Pad ........................................................... 16 Table 4-6: Welding Parameters for New J-Groove Weld ....................................................................... 16 Table 4-7: PWHT Parameters ................................................................................................................ 16 Table 6-1: List of Computer Files ........................................................................................................... 24 I
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-160 Repair Weld Residual Stress Analysis (Non-Proprietary)
List of Figures Page Figure 2-1: The Solid Model of Instrument Nozzle N16D used in the Analysis ....................................... 7 Figure 2-2: The Detailed View of Welds in the Solid Model. .................................................................... 8 Figure 2-3: Butter Welding ....................................................................................................................... 9 Figure 2-4:- J-Groove Weld Attaching Nozzle to RV Shell. ..................................................................... 10 Figure 2-5: ID Weld Overlay covering at J-Groove weld and Butter ...................................................... 1O Figure 2-6: Weld pad ............................................................................................................................. 11 Figure 2-7: Weld Pad and J-Groove weld attaching Replacement Nozzle to the Weld Pad ................. 11 Figure 4-1: Finite Element Mesh ............................................................................................................ 18 Figure 4-2: Simulation Flow Chart ......................................................................................................... 20 Figure 5-1: Distribution of Residual Axial (top) and Hoop (bottom) Stresses (psi) after Operating Cycles Step - at cold condition ............................................................................................. 22 Figure 5-2: Distribution of Residual Axial (top) and Hoop (bottom) Stresses (psi) at the end of new J-Groove weld (final step) - at cold condition ................................................................ 23 Page6
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-160 Repair Weld Residual Stress Analysis (Non-Proprietary)
1.0 INTRODUCTION
The purpose of this report is to document the results of the weld residual stress finite element analysis of the RV instrument nozzle N-16D penetration as-left J-groove weld at Limerick Unit 2 Nuclear Power Plant. This analysis includes weld simulation of the original butter and J-groove weld (including the inner diameter (ID) overlay) attaching the instrument nozzle to the reactor vessel (RV) shell. The analysis also includes simulation of the recent weld repair involving outer diameter weld pad and repair J-groove weld attaching the replacement nozzle.
As shown in Reference [3], the repair process involved removing the outer portion of the original nozzle, welding a weld pad at the outer diameter and welding of replacement nozzle to the weld pad. The state of stress as predicted by the ANSYS Version 16.0 finite element analysis at the end of welding steps is provided in this report to support fracture mechanics evaluation of a postulated flaw in the as-left J-groove weld.
2.0 ANALYTICAL METHODOLOGY The analytical methodology used to predict the weld induced residual stresses in the as-left J-groove weld involves using a three-dimensional finite element model. [
] The [ ] model used to represent the instrument nozzle penetration is shown in Figure 2-1.
Figure 2-1: The Solid Model of Instrument Nozzle N16D used in the Analysis Page?
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Figure 2-2: The Detailed View of Welds in the Solid Model The parts shown by different colors in Figure 2-2 are the reactor vessel shell, the cladding of the RV shell, the remnant nozzle, the butter and J-groove weld, the ID overlay, the existing weld buildup, the repair weld pad and repair J-groove weld attaching replacement nozzle to the weld pad.
2.1 Welding Analysis Methodology The WRS (Weld Residual Stress) finite element analysis is carried out per the WRS analysis procedure [1].
[ ] The various stages of the welding processes for the structural components including the existing/as-left J-groove weld and repair J-groove weld are simulated and consist of the following sequential steps:
- 1. Welding of the weld butter (for as-left J-groove) to the RV shell ( [ ] ) using
[ ]
- 2. Post-Weld Heat Treatment (PWHT) is simulated for the J-groove butter, RV shell, outer surface original weld buildup and RV cladding. Since PWHT was performed the original Weld Buildup ( [
] ) on the RV shell is modeled as part of the original shell structure (rather than a weld). The ID cladding which was also welded prior to the PWHT processes is also not simulated as a weld.
- 3. Welding of the as-left J-groove weld attaching remnant N-16D nozzle ([ ]) to the RV shell using [ ]
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
- 4. Welding of [ ] on the as-left J-groove weld and butter at the ID of the RV around the nozzle N-16D.
- 5. Two preservice hydrotests are simulated, followed by three operating cycles. Operational loads at steady state condition are simulated by applying the corresponding temperature and pressure as a static load step.
- 6. Simulated welding of the new weld pad ( [ ] ).
- 7. Simulated welding of the new J-groove weld ( [ ] ) attaching repair nozzle to the new weld pad. It is noted that of the three possible configurations provided on the design drawings (References [3] and [5]), the as-implemented configuration (based on repair traveler [6]) is modeled in the analysis.
As explained above this simulation follows the sequential steps that consist of building the original geometry of the instrument nozzle configuration including the butter, as-left J-groove weld and ID weld overlay. The model includes the original geometry which consists of the RV shell and cladding, the as-left J-groove weld, and the remnant nozzle as well as the repair components including weld pad, replacement nozzle and new J-groove weld.
The key steps of the welding simulations, illustrated with the finite element model, are shown in Figure 2-3 through Figure 2-7.
Figure 2-3: Butter Welding Page 9
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Figure 2-4: J-Groove Weld Attaching Nozzle to RV Shell Figure 2-5: ID Weld Overlay covering at J-Groove weld and Butter Page 10
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Figure 2-6: Weld pad Figure 2-7: Weld Pad and J-Groove weld attaching Replacement Nozzle to the Weld Pad Page 11
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
The general purpose finite element code ANSYS (Ref. [2]) is used to perform the WRS finite element analysis.
The basic steps comprising the multi-pass welding simulation of each weld simulated are as follows:
- 1. Develop the finite element model with the features necessary to accommodate the weld beads for each weld.
- 2. Define the temperature range for melting (solidus and liquidus temperatures).
- 3. Define thermal and mechanical temperature dependent material properties from ambient conditions (70°F) up to and including the melting region.
- 4. Define thermal and structural boundary conditions.
- 5. Define volumetric heat sources from welding procedure specifications.
- 6. Thermal phase using the ANSYS "birth and death" feature
- Deactivate finite elements in all weld passes.
- Activate one weld pass at a time and perform transient thermal analysis to develop the history of the temperature field for subsequent structural analysis.
- 7. Structural phase using the ANSYS "birth and death" feature
- Deactivate finite elements in all weld passes.
- Activate one weld pass at a time and perform static structural elastic-plastic analysis using the temperature history from the thermal phase.
3.0 ASSUMPTIONS 3.1 Unverified Assumptions There are no unverified assumptions used in this analysis 3.2 Justified Assumptions There are no justified assumptions used in this analysis.
3.3 Modeling Simplifications The following simplifications are used in the model:
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary) 4.0 DESIGN INPUTS 4.1 RV and N1 GD Nozzle Geometric Data The detailed dimension of the instrument nozzle N-16D modeled in the WRS finite element analysis are obtained from References [3], [4] and [5]. The key dimensions are in Table 4-1.
Table 4-1: RV and Instrument Nozzle Dimensions Dimension Value Reference(s)
Shell radius to base metal ID [3]
Cladding thickness (nominal) [4], [ ]
Shell thickness ID weld overlay thickness (nominal)
[3]
[4], - -
Original Weld buildup thickness [4],
Original Instrument Nozzle ID (towards the ID of the shell) [4],
Original Instrument Nozzle OD (towards the ID of the shell) [4],
Original Instrument Nozzle Bore ID (towards the ID of the shell) [4],
Repair Weld pad thickness [3]
Replacement Instrument Nozzle ID [6]
Replacement Instrument Nozzle OD [6]
Replacement Instrument Nozzle Bore ID [6]
4.2 RV and N1 GD Nozzle Material Information References [3], [4] and [5] provide the material designation of the components modeled in the WRS analysis.
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Table 4-2: Component Material Designation Component RV Shell - Material Designation Reference(s)
[3]
Cladding [3]
Original Weld Buildup [3]
Original I-groove butter [3]
Original I-groove Weld [3]
Original Instrument Nozzle [3]
ID weld overlay [3, 4]
New Weld Pad [3]
Replacement Nozzle [5]
I-groove Weld attaching Replacement nozzle [3]
to weld pad Physical properties for all materials including stress-strain curves are taken from reference [11]. [
1 4.3 Welding Parameters Reference [7] provides welding parameters used in the welding attachment of nozzle Nl6D to the RV.
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Table 4-3: Welding Parameters for Butter Weld Welding Parameter Value Reference(s)
Rod Diameter
- - [7]
Current [7]
Voltage Travel Speed
[7]
Typical, [1]
Maximum Interpass Temperature [7] [ ]
Table 4-4: Welding Parameters for J-Groove Weld Welding Parameter Value Reference(s)
Current (Root Pass) - - [7] [ ]
Voltage (Root Pass) [7] [ ]
Travel Speed (Root Pass) Typical, [1]
~
Rod Diameter (Remainder layers) [7]
Current (Remainder layers) [7]
[7]
Voltage (Remainder layers)
Travel Speed Typical, [1]
Maximum Interpass Temperature [7] [ ]
The weld parameters for the J-groove weld remainder passes are used for the ID overlay as well.
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Table 4-5: Welding Parameters for the New (Repair) Weld Pad Welding Parameter Value Reference(s)
Current (Layer 1) [8]
Voltage (Layer 1) [8]
Travel Speed (Layer 1) [8]
Current (Remaining Layers) [8]
Voltage (Remaining Layers) [8]
Travel Speed (Remaining Layers) [8]
Maximum Interpass Temperature
- - [8]
Table 4-6: Welding Parameters for New J-Groove Weld Welding Parameter Value Reference/(s)
Current - - [9, 7]
Voltage [7]
Travel Speed Typical, [l]
Maximum Interpass Temperature
- WPS [9] has no voltage values listed, hence typical values from [7] are used.
- [9]
Table 4-7: PWHT Parameters PWHT Parameter Value Reference/(s)
Heat up/ Cool down ratef
- - [4, 10]
Hold Temperature [4]
Hold Time [4]
t According to [ ] [7] PWHT Specification for Low Alloy Steel Plates, the heatup rate shall not exceed
[ ] . Per the ASME Construction Code [1 OJ, the PWHT heat uprate shall be not more than 400 degrees Fahrenheit per hour divided by maximum thickness (in inches). [ ]
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary) 4.4 The Finite Element Model
[
] Figure 4-2 shows the flow chart of the overall analysis sequence with corresponding input filenames.
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Figure 4-1: Finite Element Mesh Page 18
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
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Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Figure 4-2: Simulation Flow Chart 4.5 Boundary Conditions for Welding Simulation 4.5.1 Thermal Analysis - Welding Simulation The thermal model is loaded by a volumetric heat source applied to each weld pass. [
] per the Reference [ 1] WRS procedure to model natural convection to an air environment. [
1 4.5.2 Structural Analysis - Welding Simulation The temperature history from the thermal analysis is used as the thermal load in the structural analysis. [
]
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Following the butter weld, PWHT is simulated. Per Table 4-7, PWHT was performed at a nominal temperature of
[ ] and heating and cooling rates of [ ] . Heat treatment starts and ends at a temperature of 70°F. [
]
Once ID weld overlay is completed two hydro tests were simulated by applying cycles of 1.25 x design pressure at a temperature of 100°F. Pressure is applied to all wetted surfaces, and end cap pressures are applied at the original nozzle end and at the boundary plane representing horizontal cross-section of the vessel away from the nozzle. Following the hydro test operating cycles are also simulated. The cold condition (70°F, 0 psig) and operating condition [ ] [4]) are repeated 3 times.
5.0 RESULTS The welding process steps are discussed in Section 2.0. On the completion of ID weld overlay two hydrostatic tests followed by three operating cycles are simulated. The axial and hoop stress contours at cold conditions following these operating cycles are shown in Figure 5-1. The stress-contours are presented in cylindrical coordinate systems that are aligned with the axis of the nozzle, where z is axial and y is hoop; the unit of stresses is in psi. The coordinate triad shown in the contour plots represents the global coordinate system in which "X" represent the hoop, "Y" the axial direction of the RV Shell.
Following the completion of the final weld, the repair/new J-groove weld simulation, the stress state is obtained.
The axial and hoop stress contours are shown in Figure 5-2 in units of psi. The results are presented in cylindrical coordinate system aligned with the axis of the nozzle, where z is axial and y is hoop.
The ANSYS computer model files (see Table 6-1) including residual stress results are available for use in the subsequent fracture mechanics analysis.
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Figure 5-1: Distribution of Residual Axial (top) and Hoop (bottom) Stresses (psi) after Operating Cycles Step - at cold condition Page 22
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Figure 5-2: Distribution of Residual Axial (top) and Hoop (bottom) Stresses (psi) at the end of new J-Groove weld (final step) - at cold condition Page 23
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary) 6.0 COMPUTER USAGE The computer files pertinent to revision 000 of this document are located in ColdStor directory:
'\cold\General-Access\32\32-9000000\32-9274303-000\official' 6.1 Hardware / Software ANSYS Version 16.0., Reference [2], was used for all FE runs documented herein. 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 directory:
' .. \Verification' Computer program tested: ANSYS Version 16.0, verification tests vm32mod2D.vrt, vm32mod3D.vrt, vm38mod2D.vrt, and vm38mod3D.vrt.
The computer used for this analysis is a multi-node server (HPCv2), the computing node used to run this analysis was determined by PBS que scripts. The node "auslynchpc34" was used by the que for the runs. The verification runs were submitted in the same queue and the analysis results are reported in Table 6-1.
The hardware platform of auslynchpc34: Intel(R) Xeon(R) CPU E5-4650L O @ 2.60GHz; 96 GB RAM; Operating system: Red Hat Enterprise Server v6.4, kernel: 2.6.32-358.el6.x86_64.
The queue was initiated by Martin Kolar on behalf of the preparer, Silvester Noronha.
6.2 Computer Files The complete list of computer files associated with this analysis is listed in Table 6-1.
Table 6-1: List of Computer Files CRC Checksum Size Modified Date & Time File Name
./Model Data:
44166 6014 Sep 08 2017 15:11:27 34553 6756001 Sep 03 2017 10:27:24 36198 6694194 Sep 03 2017 10:25:55 34837 5870 Sep 03 2017 09:47:27
./ThermalAnalysis:
39692 576 Sep 03 2017 09:41:45 11344 493 Sep 03 2017 09:41:45 59978 998 Sep 03 2017 09:41:45 04138 598 Sep 03 2017 09:41:45 64232 659 Sep 03 2017 09:41:45 61602 10691 Sep 03 2017 09:42:22 08825 223221 Sep 08 2017 22:13:03 06847 9529 Sep 03 2017 09:42:22 Page 24
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-160 Repair Weld Residual Stress Analysis (Non-Proprietary)
CRC Checksum 55346 33448 Size 23473 10224 Modified Date & Time Sep 08 2017 22:54:49 Sep 03 2017 09:42:22
- File Name 01378 24423 Sep 08 2017 22:45:59 26056 9830 Sep 03 2017 09:42:22 24642 23864 Sep 09 2017 00:38:59 45700 10408 Sep 03 2017 09:42:22 00958 24582 Sep 09 2017 00:22:38 01259 55637 Sep 03 2017 09:41:45
./StructuralAnalysis:
49906 2156 Sep 07 2017 09:19:43 09794 474 Sep 03 2017 22:08:02 37885 11967 Sep 03 2017 22:08:02 49614 3872 Sep 03 2017 22:08:15 52775 260763 Sep 09 2017 05:09:12 51121 2851 Sep 08 2017 15:04:21 06084 12402 Sep 09 2017 14:56:41 27707 3541 Sep 04 2017 06:53:19 63127 13967 Sep 09 2017 14:35:39 32308 3771 Sep 04 2017 06:52:27 15188 14165 Sep 09 2017 12:40:24 50989 33619968 Sep 10 2017 10:48:36 06611 1.77E+08 Sep 10 2017 10:48:35 34330 3377 Sep 04 2017 06:56:27 28324 13766 Sep 10 2017 10:48:36 58179 3022 Sep 03 2017 22:08:15 42883 311104 Sep 09 2017 06:06:47 12164 3367 Sep 04 2017 06:55:41 22758 13750 Sep 10 2017 07:13:29
./Verification:
30336 3551 Sep 03 2017 12:10:55 vm32mod2D.inp 04564 55395 Sep 08 2017 21:50:01 vm32mod2D.out 48891 606 Sep 08 2017 21:50:01 vm32mod2D.vrt 42236 4940 Sep 03 2017 12:10:54 vm32mod3D.inp 00376 110067 Sep 08 2017 21:50:03 vm32mod3D.out 34040 606 Sep 08 2017 21:50:03 vm32mod3D.vrt 51869 2458 Sep 03 2017 12:10:54 vm38mod2D.inp 24568 15061 Sep 08 2017 21:50:02 vm38mod2D.out 20215 632 Sep 08 2017 21:50:02 vm38mod2D.vrt 47844 3112 Sep 03 2017 12:10:55 vm38mod3D.inp 29377 17491 Sep 08 2017 21:50:04 vm38mod3D.out 09779 632 Sep 08 2017 21:50:04 vm38mod3D.vrt Page 25
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7.0 REFERENCES
- 1. [
]
- 2. ANSYS Finite Element Computer Code, Version 16.0, ANSYS Inc., Canonsburg, PA
- 3. [
]
- 4. [
]
- 5. [
]
- 6. [
]
- 7. [
]
- 8. [
]
- 9. [ ]
- 10. ASME B&PV Code,Section III, Nuclear Vessels,1968
- 11. [
]
- 12. [
]
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APPENDIX A: VERIFICATION OF ANSYS COMPUTER CODE Four verification problems were selected to test key features of the ANSYS finite element computer program [2]
used in the current numerical welding simulations, the development of thermal stress in a cylinder and the elastic-plastic response of a cylinder under pressure loading.
The standard ANSYS verification manual test case VM32 exercises thermal and elastic stress analysis features of the axisymmetric two-dimensional 4-node PLANE55 and PLANE42 elements, respectively, using a long thick-walled cylinder subjected to a linear through-wall temperature gradient. This test case was been modified (vm32mod2D) by increasing the mesh refinement and changing the structural element type from PLANE42 to the 4-node PLANE182, which is used to verify the 2D models. A companion three-dimensional test case (vm32mod3D) was created which utilizes the SOLID70 thermal element and the S0LID185 structural element, which are used in the current welding simulations.
ANSYS verification manual test case VM38 determines stresses in a long thick-walled cylinder subjected to internal pressure using the PLANE42 axisymmetric structural element and an elastic-perfectly plastic material.
Two pressure loads are considered; the first pressure of 12,990 psi loads the cylinder elastically to just below the yield strength of the material (30,000 psi), and the second puts the entire cylinder into a state of plastic flow (von Mises equivalent stress = 30,000 psi) at an ultimate pressure load of 24,011 psi (Pult). Test case VM38 was modified (vm38mod2D) to use the PLANE182 element. The stress-strain hardening model was changed from bilinear kinematic (BKIN) to multilinear kinematic (KINH) to better represent the current welding simulations. A companion three-dimensional test case (vm38mod3D) exercises the SOLID 185 structural element. The error measure for the modified VM38 test cases is the ratio of the applied pressure to the theoretical value (24011 psi) of Pult such that the entire cylinder experiences an equivalent, or effective, stress of 30,000 psi.
All test cases executed properly, as demonstrated on the following pages.
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Verification Problem VM32M0D Thermal Stresses in a Long Cylinder Two-Dimensional Analysis File: vm32mod2D.vrt VM32MOD2D RESULTS COMPARISON TARGET ANSYS RATIO PLANE55 THERMAL ANALYSIS:
T (C) X=.1875 in -1. 00000 -1.00000 1.000 T (C) X=.2788 in -0.67037 -0.67039 1.000 T (C) X=0.625 in 0.00000 0.00000 0.000 PLANE182 STATIC ANALYSIS:
A STS psi X=.187 420.42 429.99 1.023 T STS psi X=.187 420.42 429.61 1.022 A STS psi X=.625 -194.58 -205.15 1.054 T STS psi X=.625 -194.58 -205.08 1.054 Three-Dimensional Analysis File: vm32mod3D.vrt
VM32MOD3D RESULTS COMPARISON----------------
TARGET ANSYS RATIO SOLID70 THERMAL ANALYSIS:
T (C) X=.1875 in -1. 00000 -1.00000 1.000 T (C) X=.2788 in -0.67037 -0.67039 1.000 T (C) X=0.625 in 0.00000 0.00000 0.000 SOLID185 STATIC ANALYSIS:
A STS psi X=.187 420.42 429.67 1.022 T- STS psi X=.187 420.42 430.04 1.023 A STS psi X=.625 -194.58 -205.11 1.054 T STS psi X=.625 -194.58 -205.17 1.054 Page 28
Document No. 32-9277502-000 AREVA Limerick Unit 2 Instrument Nozzle N-16D Repair Weld Residual Stress Analysis (Non-Proprietary)
Verification Problem VM38M0D Plastic loading of a Thick-Walled Cylinder Two-Dimensional Analysis File: vm38mod2D.vrt VM38MOD2D RESULTS COMPARISON TARGET ANSYS RATIO PLANE182 FULLY ELASTIC ANALYSIS (psi):
SIGR LEFT END -9984. -10103. 1. 012 SIGT LEFT END 18645. 18763. 1. 006 SIGR RIGHT END -468. -481. 1.028 SIGT RIGHT END 9128. 9141. 1.001 PLANE182 FULLY PLASTIC ANALYSIS (psi):
SIGEFF LEFT END 30000. 30000. 1. 000 SIGEFF RIGHT END 30000. 30000. 1. 000 Pult 24011. 23350. 0.972 Three-Dimensional Analysis File: vm38mod3D.vrt
VM38MOD3D RESULTS COMPARISON----------------
TARGET ANSYS RATIO SOLID185 FULLY ELASTIC ANALYSIS (psi):
SIGR LEFT END -9984. -10066. 1.008 SIGT LEFT END 18645. 18776. 1.007 SIGR RIGHT END -468. -475. 1.014 SIGT RIGHT END 9128. 9128. 1.000 SOLID185 FULLY PLASTIC ANALYSIS (psi) :
SIGEFF LEFT END 30000. 30000. 1.000 SIGEFF RIGHT END 30000. 30000. 1.000 Pult 24011. 23360. 0.973 Page 29