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| {{#Wiki_filter:,f Supplement to 1 R1 4 Steam Generator Inspection Report - | | {{#Wiki_filter:}} |
| Tube Pull Examination Results Enclosure 2 Westinghouse Electric Company LLC, SG-CDME-09-4-NP, "Report on the Examination of Vogtle Unit 1 Steam Generator Tubes"
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| Westinghouse Non-Proprietary Class 3 SG-CDME-09-4-NP January 2010 Revision 0 Examination of Steam Generator Tubes Removed from Vogtle Unit 1 Prepared for the Southern Nuclear Operating Company noWestinghouse
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| WESTINGHOUSE NON-PROPRIETARY CLASS 3 LEGAL NOTICE This report was prepared as an account of work performed by Westinghouse Electric Company LLC. Neither Westinghouse Electric Company LLC, nor any person acting on its behalf:
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| A. Makes any warranty or representation, express or implied including the warranties of fitness for a particular purpose or merchantability, with respect to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed in this report may not infringe privately owned rights; or B. Assumes any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method, or process disclosed in this report.
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| WESTINGHOUSE NON-PROPRIETARY CLASS 3 iii WESTINGI-IOUSE NON-PROPRIETARY CLASS 3 'Ii SG-CDME-09-4-NP Revision 0 Prepared for the Southern Nuclear Operating Company Examination of Steam Generator Tubes Removed from Vogtle Unit 1 Author's Name Signature / Date For Pages Thomas P. Magee TPM (*) All Verifier's Name Signature / Date For Pages David J. Ayres DJA M(*) All Manager Name .Signature / Date For Pages Earl P. Morgan EPM (*) All
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| * ElectronicallyApproved Records Are Authenticated in the ElectronicDocument ManagementSystem Westinghouse Electric Company LLC P.O. Box 355 Pittsburgh, PA 15230-0355
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| © 2010 Westinghouse Electric Company LLC All Rights Reserved
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| iv TABLE OF CONTENTS T ab le of C ontents .......................................................................................................................... iv L ist o f T ab le s ................................................................................................................................ v ii L ist of F igu re s .............................................................................................................................. v iii 1.0 In tro d uctio n ...................................................................................................................... 1-1 1.1 Steam G enerator D escription ....................................................................................... 1-1 1.2 Background for the Vogtle-1 Pulled Tubes ................................................................. 1-1 1.3 Vogtle-1 Pulled Tubes - Heat of Material ................................................................... 1-3 2 .0 R eceip t In sp ection ............................................................................................................ 2 -1 2.1 Verification of Identity and Orientation ......................... :............................................ 2-1 2.2 Visual Observations - General Conditions .................................................................. 2-1 2 .2 .1 R 1 1C 6 2 .................................................................................................................... 2 -1 2.2.2 R12C98 .......... ...................... ....................... 2-2 2.3 Visual Observations - R 11C62 Top of Tubesheet Region .......................................... 2-3 2.4 Visual Observations - R12C98 Top of Tubesheet Region ......................................... 2-3 2.5 Visual Observations - R12C98 Flow Distribution Baffle Region .............................. 2-3 2.6 Visual Observations - R12C98 First Hot Leg Tube Support Plate Region ................. 2-3 2.7 D im ensional C haracterization ...................................................................................... 2-4 3.0 E ddy C urrent T est Inspection .......................................................................................... 3-1 3 .1 Intro d u ctio n .................................................................................................................. 3 -1 3.2 Eddy Current (EC) Data - General Practices ............................................................... 3-1 3.3 Field Eddy Current Test Data and Laboratory Reevaluation of Field Eddy Current Test Data for Tube R12C98 HL ..................................................................... 3-3 3.3.1 Field Eddy Current Test Data for the TTS Region of Tube R12C98 HL ................ 3-3 3.3.2 Field Eddy Current Test Data for the FDB Region of Tube R12C98 HL ............... 3-3 3.3.3 Field Eddy Current Test Data for the TSPI Region of Tube R12C98 HL .............. 3-3 3.4 Field Eddy Current Test Data and Laboratory Reevaluation of Field Eddy Current Test Data for Tube R 11C62 HL ..................................................................... 3-3 3.4.1 Field Eddy Current Test Data for the TTS Region of Tube RI 1C62 HL ................ 3-3 3.5 Laboratory Eddy Current Test Data for Tube R12C98 HL ........................................ 3-4 3.5.1 Laboratory Eddy Current Test Data for the TTS Region of Tube R12C98 HL (P ie c e 2 ) ................................................................................................................... 3-4 3.5.2 Laboratory Eddy Current Test Data for the FDB Region of Tube R12C98 HL (P ie c e # 3 ) ................................................................................................................. 3 -4 3.5.3 Laboratory Eddy Current Test Data for TSP I Region of Tube R12C98 HL (P ie c e # 4 ) ................................................................................................................ 3-4 3.6 Laboratory Eddy Current Test Data for Tube R 11C62 HL ......................................... 3-5 3.6.1 Laboratory Eddy Current Test Data for the TTS Region of Tube Ri1C62 HL (P C # 2 ) ...................................................................................................................... 3 -5 4 .0 Ultrason ic Inspection ....................................................................................................... 4-1 4.1 Scope of Ultrasonic Inspections and Description of Techniques ................................ 4-1 Table of Contents January 2010 SG-CDME-09-4-NP Revision 0
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| v 4.2 Laboratory U ltrasonic Inspection Results .................................................................... 4-2 4.2.1 Laboratory UT of Tube R 12C98 HL in the TTS Region ......................................... 4-2 5.0 Pseudo Lam b W ave UT Technique ................................................................................. 5-1 5.1 Introduction .................................................................................................................. 5-1 5.2 Equipm ent .................................................................................................................... 5-1 5 .3 R e su lts .......................................................................................................................... 5 -2 5.3.1 Laboratory Lamb Wave UT of Tube R12C98 HL in the TTS Region .................... 5-2 6.0 Deposit pH ....................................................................................................................... 6-1 7.0 Burst Test ........................................... ............................................................................ :.7-1 7.1 Sam ple Preparation ...................................................................................................... 7-1 7.2 Leak Screening ............................................................................................................ 7-2 7.2.1 Purpose ..................................................................................................................... 7-2 7.2.2 Results ....................... I.............................................................................................. 7-2 7.3 Burst Test Set-Up ......................................................................................................... 7-3 7.4 Burst Test Results ......................................................................................................... 7-4 7.5 Calculated Burst Pressure ............................................................................................ 7-5 7.5.1 RilC62 Axial Cracks .............................................................................................. 7-5 7.5.2 R 12C98 Circum ferential Cracks .............................................................................. 7-6 7.5.3 Freespan Tubing ....................................................................................................... 7-7 7.6 Post-Burst Observations ............................................................. ....... 7-8 8.0 Sectioning ........................................................................................................................ 8-1 9,0 Fractography .................................................................................................................... 9-1 9.1 Procedure ..................................................................................................................... 9-1 9.2 Crack Surface Characterization ................................................................................... 9-1 9.3 ED S Analysis of Crack Surfaces ................................................................................. 9-2 9.4 SEM /ED S Analysis of OD Surfaces and D eposits ...................................................... 9-3 9.5 D epth Profiles .................. :................................................................................... 9-3 10.0 M etallography of Cracks ................................................................................................ 10-1 10.1 Procedure ................................................................................................................... 10-1 10.2 RI IC62 Axial Crack .................................................................................................. 10-1, 10.3 R 12C98 Axial Crack .................................................................................................. 10-1 10.4 R 12C98 Circum ferential Crack ................................................................................. 10-1 11.0 M aterial Characterization ........................................................................................... 11-1 11.1 Tensile Test ................................................................................................................ 11-1 11.2 Bulk Chem istry .......................................................................................................... 11-1 11.3 M icrostructure Analysis ............................................................................................. 11-2 11.3.1 Procedure ............................................................................................................... 11-2 11.3.2 Grain Size .............................................................................................................. 11-2 11.3.3 M icrostructure ........................................................................................................ 11-2 11.4 M icrohardness Testing ............................................................................................... 11-3 11.4.1 Procedure ............................................................................................................... 11-3 1 1.4 .2 Re su lts .................................................................................................................... 1 1-4 11.5 Sensitization Assessm ent ........................................................................................... 11-4 Table of Contents January 2010 SG-CDME-09-4-NP Revision 0
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| vi 11.5.1 Procedure .............................................................................................................. 11-4 11.5.2 Results .................................................................................................................... 11-5 11.6 Residual Stress ........................................................................................................... 11-5 11.6.1 Introduction ............................................................................................................ 11-5 11.6.2 Procedure ............................................................................................................... 11-5 11.6.3 Results .................................................................................................................... 11-6 11.7 Surface Roughness ..................................................................................................... 11-6 12.0 Discussion / Conclusions ............................................ 12-1 12.1 Tube Integrity ....................................................................... 12-1 12.2 Cause of Cracking ...................................................................................................... 12-1 12.2.1 M aterial Condition ................................................................................................. 12-1 12.2.2 Stress ................................................................... ........ 12-2 12.2.3 Chem istry ............................................................................................................... 12-3 12.3 A 600TT Field Perform ance ....................................................................................... 12-3 12.3.1 Seabrook Pulled Tubes .......................................................................................... 12-4 12.3.2 Plant A Pulled Tubes ............................................................................................. 12-5 12.3.3 Vogtle-2 Pulled Tubes ........................................................................................... 12-6 12.4 Steam G enerator Operation ...................................................................................... 12-6 12.5 Tube Processing Overview ........................................................................................ 12-7 12.6 Conclusions ................................................................................................................ 12-9 13.0 References ...................................................................................................... ................ 13-1 Table of Contents January 2010 SG-CDME-09-4-NP Revision 0
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| vii LIST OF TABLES Table 1-1: Support P late E levations ...................................................................................... 1-4 Table 1-2: O D SC C Indications at Vogtle-1 .......................................................................... 1-5 Table 1-3: As-R eceived L engths ........................................................................................... 1-6 Table 2-1: Laser Micrometer Start/Stop Positions ................................................................ 2-6 Table 2-2: Pre-Burst Test Wall Thickness Measurements .................................................... 2-6 Table 3-1: Summary of Field and Laboratory Eddy Current Inspection Results .................. 3-6 Table 7-1: Post-B urst M easurem ents ..................................................................................... 7-9 Table 7-2: C alculated Burst Pressures ................................................................................... 7-9 Table 8-1: C uttin g D iagram s ................................................................................................. 8-1 Table 9-1: Summary of EDS Analyses Performed on Crack Surfaces ................................. 9-5 Table 9-2: Summary of EDS Analyses Performed on OD Surfaces ................. 9-6 Table 9-3: Summary of R 11C62 Depth Profiles ............................... 9-7 Table 10-1: M etallography Samples ..................................................................................... 10-3 Table I l-i1: Chemical Composition of Bulk Material ........................................................... 11-7 Table 11-2: G rain Size Sum m ary .......................................................................................... 11-7 Table 11-3: Summary of Modified Huey Results ................................................................. 11-8 Table 11-4: Summary of Residual Stress Measurements ...................................................... 11-8 Table 12-1: Comparison of Field Sizing and Lab Results ........................ 12-10 Table 12-2: Operating Plant SGs Equipped with Alloy 600TT Tubes ............................... 12-11 Table 12-3: Original SGs with Alloy 600TT Tubing - Estimated Total Number of Tubes Plugged Due to Suspected Corrosion ................................................... 12-12 Table 12-4: H eats w ith O D SCC at Vogtle-1 ....................................................................... 12-13 List of Tables January 2010 SG-CDME-09-4-NP Revision 0
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| viii LIST OF FIGURES Figure 2-1: Orientation System Used in the Exam ination ...................................................... 2-7 Figure 2-2: R 1 1C 6 2 T T S ........................................................................................................ 2 -8 Figure 2-3: R 11C 62 T T S C racks .......................................................................................... 2-10 Figure 2-4: R 12 C 9 8 T T S ..................................................................................................... 2 -1 1 Figure 2-5: R 12C 98 T T S C racks .......................................................................................... 2-13 Figure 2-6: R 12 C 9 8 F D B ..................................................................................................... 2 -14 Figure 2-7: R 12 C 9 8 T S P 1 .................................................................................................... 2 -16 Figure 2-8: TTS Region of R12C98 Showing the Expansion Transition ............................. 2-18 Figure 2-9: Transition Expansion of R12C98 (Figure 2-8 Rotated) ..................................... 2-19 Figure 2-10: FDB Region of R12C98 Showing No Ovality .................................................. 2-20 Figure 2-11: TSP1 Region of R12C98. Small "Bumps" Are Attributable to Tube Pull G rip p er M ark s ..................................................................................................... 2 -2 1 Figure 2-12: T T S R egion of R 11C 62 ..................................................................................... 2-22 Figure 3-1: TM Plot of the 300 Khz +Point Coil Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ......... 3-7 Figure 3-2: Plot of the Delta Coil Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ........................ 3-8 Figure 3-3: Plot of the 400 Khz Ghent Probe Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ......... 3-9 Figure 3-4: Plot of the Bobbin Coil Probe Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing a Response at the Hot Leg First Tube Support Plate (T S P 1)................................................................................................................ 3 -10 Figure 3-5: Plot of the Bobbin Coil Probe Field Data from Vogtle-1 SG 4 of R12C98 Showing a Response at the Hot Leg FDB ......................................................... 3-11 Figure 3-6: Plot of the 300 Khz +Point TM Coil Field Data from Vogtle Unit 1 SG 4 of R1IC62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ....... 3-12 Figure 3-7: Plot of the Delta Coil Field Data from Vogtle Unit 1 SG 4 of R 11C62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ...................... 3-13 Figure 3-8: Plot of the 300 Khz Ghent Probe Field Data from Vogtle Unit 1 SG 4 of R1IC62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ....... 3-14 Figure 3-9: Plot of the 300 Khz Pancake Coil Field Data from Vogtle Unit 1 SG 4 of R 11C62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ....... 3-15 Figure 3-10: Laboratory +PointTM Coil Response from the TTS Region of R12C98 (P C # 2) ................................................................................................................ 3 - 16 Figure 3-11: Plot of the 300 Khz Delta Probe Laboratory Data of R12C98 (PC#2)
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| Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ...................... 3-17 Figure 3-12: Plot of the 400 Khz Ghent Probe Laboratory Data from Vogtle Unit 1 SG 4 of R12C98 (PC#2) Showing an Indication at the Hot Leg Top of Tube S h eet (T T S) ........................................................................................................ 3 -18 Figure 3-13: Laboratory 300 Khz +PointTM Coil Response from the TTS Region of R 11C 62 (P C # 2) .................................................................................................. 3 -19 Figure 3-14: Plot of the 300 Khz Pancake Coil Laboratory Data from Vogtle Unit 1 SG 4 of R1IC62 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sh eet (T T S ) ........................................................................................................ 3-2 0 List of Figures January 2010 SCG-CDMF-09-4-NP Revision 0
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| ix Figure 3-15: Plot of the 300 Khz Delta Probe Laboratory Data of R 1IC62 (PC#2)
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| Showing an Indication at the Hot Leg Top of Tube Sheet (TTS) ...................... 3-21 Figure 3-16: Plot of the 300 Khz Ghent Probe Laboratory Data from Vogtle Unit 1 SG 4 of R 11C62 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sh eet (TT S ) ........................................................................................................ 3 -2 2 Figure 3-17: Plot of the Bobbin Coil Probe Laboratory Data from Vogtle Unit 1 SG 4 of R12C98 (PC#2) Showing a Response at the Hot Leg TTS ........................... 3-23 Figure 4-1: UTEC Response to Calibration Standard UE-001-96 ......................................... 4-4 Figure 4-2: Laboratory UTEC ultrasonic results for the TTS region (Piece 2B) of R 12 C 98 H L ......................................................................................................... 4 -5 Figure 5-1: Ultrasonic Contact Probe for Launching Lamb Waves from the Inside of th e T u b e . ................................................................................. ........................... 5 -3 Figure 5-2: Photograph of the 3.5 MHz Lamb Wave Probe Compatible with the UTEC Sy stem ........................................................................................................... . . 5-3 Figure 5-3: Lamb Wave Response of Calibration Tube UE-001-96 ...................................... 5-4 Figure 5-4: Plot of the Lamb Wave Response of Vogtle Unit 1 SG 4 of R12C98 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet(TTS) ........... 5-5 Figure 7-1: Burst Test Support Simulation....................................... 7-10 Figure 7-2: Burst Opening at RI 1C62 TTS (at 1600 Orientation)>. ...................................... 7-11 Figure 7-3: Burst Opening at R 11C62 Freespan (at 800 Orientation) .................................. 7-12 Figure 7-4: Burst Opening at R12C98 TTS (at 240' Orientation) ..................... ................. 7-13 Figure 7-5: Burst Opening at R12C98 Freespan (at 225' Orientation) ............................... 7-14 Figure 7-6: Post-Burst Observations on R I 1C62................................................................. 7-15 Figure 7-7: R1 1C62 TTS Post-Burst Close-Up Views ......................................................... 7-16 Figure 7-8: ID View of R 11C62 TTS Region ...................................................................... 7-17 Figure 7-9: Post-Burst Observations on R 12C98 ................................................................. 7-18 Figure 7-10: R12C98 TTS Post-Burst Close-Up Views ............... ........... 7-19 Figure 7-11: Circumferential Cracks at the TTS of R12C98 (view = up) .............................. 7-21 Figure 8-1: R 11C 62 Section 1 (not sectioned) ....................................................................... 8-2 Figure 8-2: Cutting Diagram for R 11C62 Section 2 (Post-Burst Test) ................................. 8-3 Figure 8-3: Ri 1C62 Section 2A Cutting and Examination Plan ............................................ 8-4 Figure 8-4: Cutting Diagram for R 11C62 Section 3 (Post-Burst Test) ................................. 8-5 Figur-e8-5U.- R11IC62 Section 3B Cutting and Examination Plan..... ............ _85 Figure 8-6: R12C98 Section 1 (not sectioned) ................................. 8-6 Figure 8-7: R12C98 Section 2 (Post-Burst Test) ............................... 8-7 Figure 8-8: R12C98 Section 2A2 Cutting and Examination Plan .......................................... 8-8 Figure 8-9: Cutting Plan for R12C98 Section 3 (for Eddy Current Testing) ......................... 8-9 Figure 8-10: Cutting Plan for R 12C98 Section 3 ................................. .... .......................... 8-10 Figure 8-11: Cutting Plan for R 12C98 Section 4 ................................. .......................... 8-11 Figure 8-12: Cutting Plan for R 12C98 Section 5 ................................................................... 8-12 Figure 8-13: R12C98 Section 5A Cutting Diagram and Examination Plan ............. 8-13 Figure 8-14: Archive Tubing Cutting and Examination Plan ........................... 8-14 Figure 9-1: Overall Views of RI IC62 1600 Crack (Sample 2A2A) ...................................... 9-8 Figure 9-2: Overall Views of R I C62 2100 Crack (Sample 2A2A) ...................................... 9-9 Figure 9-3: Overall Views of RI IC62 270' Crack (Sample 2A2C) .................................... 9-10 Figure 9-4: Secondary Electron SEM View of R12C98 Crack Surface ............................... 9-11 List of Figures January 2010 SG-CDME-09-4-NP Revision 0
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| X Figure 9-5:
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| Figure 9-6: R 1IC62 1600 Crack - Crack Tip Example by SEM ......................................... 9-14 Figure 9-7: R 11C62 2100 Crack Exam ple by SEM .............................................................. 9-15 Figure 9-8: R 11C62 270' Crack Exam ple by SEM .............................................................. 9-15 Figure 9-9: R 12C98 Crack Exam ples by SEM ..................................................................... 9-16 Example of EDS Analysis of Crack Surface (R11C62 1600 Crack-Mid-Figure 9-10: C ra ck ) ................................................................................................................. 9 -17 Example of Crack Surface Deposit for EDS Analysis (R 11C62 1600 Figure 9-11: Cra ck ) ................................................................................................................. 9 -17 OD Surface of RI 1C62, Between 1600 and 2100 Orientations (Sample Figure 9-12: 2A 2 A) ..................................................................... !.......................................... 9- 18 Figure 9-13: Sm all Axial Cracks at the 1650 Orientation ....................................................... 9-19 Figure 9-14: IG A N ear R i 1C 62 1600 C rack .......................................................................... 9-20 Figure 9-15: Region Above R12C98 Circ Crack, Showing IGA and Deposits ..................... 9-21 Figure 9-16: Depth Profile of R 11C62 TTS Crack at 160. .................................................... 9-22 Figure 9-17: Depth Profile of R 11C62 TTS Crack at 2100 .................................................... 9-23 Figure 9-18: Depth Profile of RI IC62 TTS Crack at 2700 .................................................... 9-24 Figure 10-1: D epth Profile of R 12C98 TTS Cracks ............................................................... 9-25 Figure 10-2: R 11C62 1600 Crack - O D V iew ........................................................................ 10-4 Figure 10-3: R 11C 62 1600 Crack - ID V iew ......................................................................... 10-5 Figure 10-4: R"1C62 1450 Crack - O D V iew ........................................................................ 10-6 Figure 10-5: R12C98 Cracks at 1600 Seen in a Transverse Section ...................................... 10-7 Figure 10-6: R 12C 98 A xial C rack at 1350 ............................................................................. 10-8 Figure 10-7: R12C982 Circ Crack at 270' - OD View .......................................................... 10-9 R12C982 Circ Crack at 2700 - ID View ......................................................... 10-10 Figure 11-1: Stress-Strain C urve for R 12C 98 ........................................................................ 11-9 Figure 11-2: Stress-Strain Curve for Archived Tubing (Heat 2272) .................................... 11-10 Figure 11-3: Microstructure of R 11C62 (Sample 2A2B1) After a Nital Etch ....................... 11-1 Figure 11-4: Carbide Distribution of R 11C62 Near the TTS (Sample 2A2B1) ..................... 11-2 Figure 11-5: Carbide Distribution of R 11C62 Remote from TTS (Sample 3B3B) ................ 11-4 Figure 11-6: Carbide Distribution of R12C98 Near from TTS (Sample 2A2B2) .............. 1176 Figure 11-7: Carbide Distribution of R12C98 Near from TTS (Sample 2A2B3) .................. 11-8 Figure 11-8: Carbide Distribution of R12C98 Remote from TTS (Sample 5A5B) ............. 11-12 Figure 11-9: Carbide Distribution of Heat 2272 Archive (Sample XA4B).......................... 11-14 Figure 11-10: Microstructure of Vogtle-2 Tube Pulled in 2004 ............................................. 11-18 Figure 11-11: Microstructure of Seabrook Tube Pulled in 2002 ............................................ 11-19 Figure 11-12: Microhardness Traverses on Tube R 11C62 ......................... 11-20 Figure 11 -13: Microhardness Traverses on Tube R12C98 ......................... 11-21 Figure 11-14: R 11C62 (Sample 2A3) Axial ID Surface Roughness ...................................... 11-22 Figure 11-15: R 11C62 (Sample 2A3) Circumferential ID Surface Roughness ..................... 11-22 Figure 11-16: R 11C62 (Sample 2A3) Axial OD Surface Roughness .................................... 11-23 Figure 11-17: R1IC62 (Sample 2A3) Circumferential OD Surface Roughness .................... 11-23 Figure 11-18: R12C98 (Sample 5A5A) Axial ID Surface Roughness ................................... 11-24 Figure 11-19: R12C98 (Sample 5A5A) Circumferential ID Surface Roughness .................. 11-24 Figure 11-20: R12C98 (Sample 5A5A) Axial OD Surface Roughness ................................. 11-25 Figure 11-21: R12C98 (Sample 5A5A) Circumferential OD Surface Roughness ................. 11-25 Figure 11-22: Archive Tubing (Heat 2272) Axial ID Surface Roughness ............................. 11-26 List of Figures January 2010 SG-CDME-09-4-NP Revision 0
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| xi Figure 11-23: Archive Tubing (Heat 2272) Circumferential ID Surface Roughness ............. 11-26 Figure 11-24: Archive Tubing (Heat 2272) Axial OD Surface Roughness ........................... 11-27 Figure 11-25: Archive Tubing (Heat 2272) Circumferential OD Surface Roughness ........... 11-27 Figure 12-1: Comparison of Vogtle- 1 and Vogtle-2 Expansion Transitions ........................ 12-14 Figure 12-2: Tubing M anufaturing Tim eline ....................................................................... 12-15 Figure 12-3: Tube M anufacturing Sequence ........................................................................ 12-16 Figure 12-4: Thermal Treatment Facility: (a) Vacuum Furnace .......................................... 12-17 Figure 12-5: Thermal Treatment Facility: (b) Furnace Controls .......................................... 12-18 Figure 12-6: Thermal Treatment Furnace Loading Rack ......................... 12-19 Figure 12-7: Schematic of Furnace Loading for U-Bend Stress Relief................. 12-20 List of Figures January 2010 SG-CDME-09-4-NP Revision 0
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| 1-1
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| ==1.0 INTRODUCTION==
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| 1.1 Steam Generator Description Vogtle Unit 1 (Vogtle-1) is a four loop Westinghouse designed pressurized water reactor, sited in Burke County, Georgia, and operated by the Southern Nuclear Operating Company (SNOC).
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| Vogtle- 1, which has a nominal rating of 1100 MWe (net), commenced commercial operation in 1987 and has accumulated 19.8 effective full power years (EFPY) of operation at the time of the fifteenth refueling outage (1R15) in the Fall of 2009 (Reference 1).
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| The Vogtle-l steam generators are of the Model F type, manufactured by the Westinghouse Electric Corporation. Each steam generator (SG) contains 5626 thermally treated FeCrNi Alloy 600 (A600TT) heat transfer tubes, of which 121 were plugged prior to the 1R15 outage.
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| The Vogtle-1 tubes are nominally 11/16 inch in outer diameter and have a nominal wall thickness of 40 mils. The tubes are arranged in a square pattern, with centerlines spaced 0.98 inch apart The tubes were hydraulically expanded the full-depth of each low alloy steel tubesheet, which is approximately 21.2 inches thick, including the cladding (Reference 2).
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| Each tube passes through seven tube support plates (TSPs) that are 1.12 inches thick each. Each TSP is fabricated from A-240 Type 405 stainless steel. Each tube passes through each TSP through a quatrefoil broached-hole that has a minimum diameter of 0.709 inch. Table 1-1 provides a summary of the as-built elevations of the supports (Reference 2).
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| Most of the tubes also pass through a flow distribution baffle (FDB) that is located 20.4 inches above the top of the tubesheet (TTS) and 19.68 inches below the first TSP. The FDB is 0.75 inch thick. The FDB is fabricated from A-240 Type 405 stainless steel and most tubes pass through the FDB through octofoil broached-holes that each have a minimum diameter of 0.750 inch.
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| Tubes located near the center of the steam generator pass through a cutout in the FDB and thus do not pass through a FDB broached hole.
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| 1.2 Background for the Vogtle-1 Pulled Tubes Steam generator tubes with crack-like indications were first identified near the top of the tubesheet during the 1R13 Vogtle Unit 1 steam generator inspection (Fall 2006).Prior to 1R13, Vogtle-l tube degradation consisted of wear (AVBs, maintenance, loose parts) and primary water stress corrosion cracking (PWSCC) at tubesheet bulge indications. There had been no prior false positive ODSCC indications in the Vogtle-1 tubes, as was the case with Plant A (Reference
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| : 5) and Vogtle Unit 2 (Reference 6) A600TT tubes.
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| Additional TTS ODSCC indications were identified during the 1R14 and IR15 inspections (Spring 2008 and Fall 2009, respectively) in the Vogtle-1 SGs. Table 1-2 summarizes the ODSCC at Vogtle-1, which includes both axial and circumferential ODSCC. All 1R14 indications were found to have been present in the 1R13 data, though they were not reported at that time. The IR15 analyses were adjusted to cause small, otherwise resolvable indications to be reported as flaws. All 20 of the circumferential ODSCC indications reported during 1R15 were Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 1-2 detectable in the 1R14 ECT data but carried in service as TRA (follow but don't plug) signals or were resolved as NDD.
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| Application of NDE experience gained from false positive indications at other A600TT plants, the relatively large size of the 1R14 indications and the relatively long operating time of the Vogtle steam generators, provided a high degree of confidence that the 1R14 indications were indeed cracks. SNOC proactively decided to extract tubes from the Vogtle Unit 1 steam generators for laboratory examination during the 1R14 outage, to definitively characterize and size, as well as ascertain potential causes of any corrosion associated with these or similar indications. Two tubes were pulled from the hot leg of SG 4 of Vogtle-1 in the spring of 2008:
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| R11C62 and R12C98.
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| Tube R 11C62 had an axial ODSCC indication in the expansion transition region near the HL TTS. This indication had an estimated maximum depth of 77%TW, based on an amplitude vs.
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| destructive depth correlation (Reference 11). This indication was found to be present in the 1R13 inspection data as a non-reportable indication. It was not present in the 1R12 data. It was apparent from the ECT data that the indication was positioned almost entirely below the bottom of the expansion transition. The upper tip of the crack and the bottom of the expansion transition were close to but below the top of the tubesheet; the crack extended into the fully expanded portion of the tube (Reference 12).
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| R 11 C62 was chosen for laboratory examination because it was the only axial indication found during the 1R14 inspection. Tube R 11C62 passes through the FDB cutout and thus does not have a FDB intersection. The tube was cut just below the second hot leg support. However, the tube cut was incomplete and when the tube was pulled it did not break free and was consequently damaged during the tube pulling operation. The tube had to be cut at an intermediate point about 8 inches above the TTS to remove it from the steam generator.
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| R12C98 had a circumferential ODSCC indication in the expansion transition region near the TTS. This indication had an estimated maximum depth of 54%TW, based on an amplitude vs.
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| destructive depth correlation (Reference 12). This indication was found to be present in the 1R13 inspection data as a non-reportable indication. It was not present in the 1R12 data.
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| R12C98 was selected since it had the highest +Point TM 1 VM value (0.44 volts) though its crack angle was only 51 °. The cutting and extraction of R12C98 was performed without difficulty.
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| The tube was cut just below the second hot leg support.
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| These two tubes were cut into a total of eight sections (see Table 1-3) and provided to Westinghouse's Science and Technology Department (STD) facility in Churchill, Pennsylvania for non-destructive examination (NDE) and destructive examination. The examinations included:
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| a Verification of Sample Identification - For all tubes, all segments were measured for length and visually surveyed for landmark features (e.g., TSP intersections) for comparison with tube removal records.
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| I +PointTM is a trademark of Zetec, Inc.
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| Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 1-3 o Visual characterization of the pulled tubes. The purpose of this examination was to identify and characterize any tube degradation, characterize the appearance of any secondary side deposits, and identify any damage from the tube pulling operation. Results were documented by photography.
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| * Eddy current characterization, including a bobbin exam, +PointTM, Ghent, 3-coil Delta exams, andultrasonic testing (UT). This information served to precisely locate defects for the metallography and to determine any differences from the pre-pull inspection.
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| * The OD profile of tube segments in areas of interest (TTSs, FDB and TSP).
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| " Characterization of surface deposits, including pH, appearance and approximate elemental composition.
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| * SEM/EDS characterization of mechanically opened cracks and burst openings. Develop length versus depth profile with sufficient data points that a linear interpolation between data points yields the crack profile and average depth.
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| * Metallographic examination of the cracks and tube material.
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| * Determination of burst pressure.
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| * Hoop stress measurements.
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| " Non-degraded tubing from a free-span area was tensile tested to ASTM standards to' determine the yield strength, ultimate tensile strength, percent elongation, and reduction in area.
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| * Characterization of the tubing material by microhardness testing and sensitization testing.
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| * Determine the bulk chemistry of the tubing material.
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| Westinghouse has completed all of the above examinations on the tubes removed from Vogtle- 1.
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| This report documents the examinations performed and the results from the examinations.
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| All examinations and testing presented in this report were treated as safety-related and are in accordance with the Westinghouse Quality Assurance program (Reference 13)', which satisfies the requirements of 10CFR50 Appendix B. This examination was initiated by the Reference 14 work authorization.
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| 1.3 Vogtle-1 Pulled Tubes - Heat of Material A review was performed that correlated most Vogtle-I tubes with their respective heat number (Reference 15). This review indicates that both pulled tubes were from Heat 2272. A single heat of material will have the same ladle chemistry, but subsequent processing of the material into tubular form can result in differences in the mechanical properties of the tube itself and possible minor difference in bulk chemistry. Table 11-1 shows that the pulled tubes had nearly identical bulk chemistry. Heat 2272 has a carbon content of 0.03 wt%, as determined from the ladle analysis. The tensile test of Heat 2272 showed a yield strength of 46 ksi and an ultimate strength of 102 ksi.
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| Westinghouse has a number of archived heats of tubing from the tubing manufacturer. The heat numbers are vibra-etched onto the end of each archived tube. Westinghouse located one -13 inch length of tubing from Heat 2272. This length of tubing was also examined for a comparison of tubing properties.
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| Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 1-4 Table 1-1: Support Plate Elevations (Reference 2)
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| IDiance Above Ttbe Monuth Distanilce Above TTS Tube Mouth 0 Primary Side of Clad 0 (tube mouth flush with clad)
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| Primary Side of Tubesheet 0.2 Top of Tubesheet (TTS) 21.23 0 Centerline of FDB 41.605 20.375 Centerline of TSP#1 61.290 40.060 Centerline of TSP#2 101.880 80.650 Centerline of TSP#3 142.090 120.860 Centerline of TSP#4 182.300 161.070 Centerline of TSP#5 222.510 201.280 Centerline of TSP#6 262.720 241.490 Centerline of TSP#7 302.930 281.700 January 20100 Revision Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 1-5 Table I-2: ODSCC Indications at Vootle-I Dist. Dist.
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| from from Outage SG Row Col Volts Ind TTS Outage SG Row Col Volts Ind TTS IR13 1 1 103 0.21 SCI -0.08 IR15 1 2 113 0.07 MCI -0.05 IR13 1 3 103 0.22 SCI -0.07 IR15 1 3 108 0.13 MCI -0.07 1R13 1 3 119 0.12 SCI -0.1 IR15 1 5 110 0.1 SCI -0.1 1R13 2 2 109 0.60 SCI -0.07 IR15 1 7 106 0.13 SCI -0.11 1R13 2 2 113 0.13 SCI -0.12 IR15 1 7 117 0.11 SCI -0.1 1R13 3 2 106 0.12 SCI -0.08 IR15 1 8 115 0.09 SCI -0.1 1R13 3 5 118 0.48 SCI -0.13 iR15 1 10 104 0.16 SCI -0.07 1R13 3 6 112 0.18 SCI -0.07 IR15 1 10 112 0.07 MCI -0.12 1R13 4 4 107 0.16 SCI -0.04 IR15 1 12 120 0.14 SCI -0.1 1R13 4 6 105 0.73 MCI -0.04 iR15 1 15 115 0.09 SCI -0.8 1R13 4 8 106 0.21 SCI -0.05 iR15 2 13 62 0.31 SCO 0.1 1R13 4 8 108 0.68 MCI -0.11 IR15 2 22 103 0.1 SCI 0 IR13 4 8 113 0.29 SCI -0.08 IR15 3 2 109 0.11 MCI -0.13 1R13 4 9 107 0.18 SCI -0.06 IR15 3 3 106 0.11 SCI -0.11 1R13 4 11 115 0.69 MCI -0.19 iR15 3 6 114 0.25 SCI -0.1 1R13 4 22 84 0.35 SCI -0.07 IR15 3 7 113 0.12 SCI -0.1 1R13 4 25 51 0.51 MCI -0.08 1RI5 4 3 105 0.1 SCI -0.16 IR15 4 4 113 0.06 SCI -0.19 1R14 1 6 110 0.21 MCI -0.15 IR15 4 4 117 0.09 SCI -0.13 1R14 1 8 112 0.14 SCI -0.17 IR15 4 4 122 0.13 SCI -0.1 1R14 1 10 114 0.16 SCI -0.16 IR14 1 11 118 0.21 SCI -0.02 1R14 1 13 96 0.35 SCI 0.02 Axial Indications 1R14 2 34 104 0.16 SCI -0.19 1R13 4 5 68 1.58 SAI -0.17 1R14 3 6 119 0.16 SCI 0 1R14 4 11 62 0.71 SAI -0.19 1R14 3 13 107 0.24 SCI -0.11 1R14 4 12 98 0.44 SCI -0.06 1R14 4 22 51 0.38 SCI -0.08 Note:
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| - All indications were found on the hot leg.
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| - All 1R14 indications were found to have been present in the 1R13 data, though they were not reported at that time. The IR 15 analyses were adjusted to cause small, otherwise resolvable indications to be reported as flaws.
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| Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 1-6 Table 1-3: As-Received Lengths Length of Angled Length of Total Straight* Cut on Bottom Angled Cut on Length Tube Section Region Length (in) End (in) Top End (in) (ino R11C62 1 Tubesheet 6.50 0 0.63 7.13 2 TTS 16.75 0.75 0 17.50 3 Freespan 8.56 0 0 8.56 R12C98 1 Tubesheet 5.00 0 0.63 5.63 2 TTS 22.63 0.63 0.75 24.00 3 FDB 23.25 0.75 0.75 24.75 4 TSP1 19.25 0.75 0.75 20.75 5 Freespan 23.00 0.75 0 23.75 R 11C62 cracks located about 14.8" from bottom of piece 2 (including angled cut)
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| R12C98 TTS located 15.6" from bottom of piece 2 (including angled cut)
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| R12C98 FDB centered 12" from bottom of piece 3 (including angled cut)
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| R12C98 TSP1 centered 7.5" from bottom of piece 4 (including angled cut)
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| Introduction January 2010 SG-CDME-09-4-NP Revision 0
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| 2-1 2.0 RECEIPT INSPECTION 2.1 Verification of Identity and Orientation These two tubes were cut into a total of eight sections (see Table 1-3) and provided to Westinghouse's Science and Technology Department (STD) facility in Churchill, Pennsylvania for non-destructive examination (NDE) and destructive examination. The sections were provided in separate hard clear plastic tubes. Each section was clearly identified with the tube section number on the clear plastic packaging.
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| Upon receipt of the tubes in the laboratory, Westinghouse compared labels and section lengths of each section with tube pull operation documentation. This confirmed that all of the intended sections had been shipped to the lab, that the laboratory personnel understood the labeling and that the orientation of the tubes was understood (up vs. down and azimuthal location). This confirmation is documented in Reference 16.
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| The identification and traceability of specimens were maintained in accordance with established Westinghouse procedure (Reference 17). In this report, the tenns "section" and "piece" may be used interchangeably; each refers to a part cut from its parent tube. A "specimen" generally refers to a sample Used in a specific test. The designation of each cut specimen includes the number of the original piece. For instance, specimen 2B was cut from piece 2, and specimen 2B 1 was cut from piece 2B, etc. An orientation system was arbitrarily chosen to aid in the description of the tube specimens. As each tube was pulled from the tubesheet, it was cut at an angle to the axial direction such that azimuthal locations could be referenced to their position in the generator. The 00 orientation of each specimen was related to the pointed end at the bottom of the tube piece, and 900 is clockwise of 00 when looking in the upward (primary flow) direction (see Figure 2-1). Using this orientation system, the 270' side of RI 1C62 is the side closest to the divider plate; the divider plate side of R12C98 is at the 2400 azimuthal location. Unless otherwise stated, this orientation system is used throughout this report.
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| 2.2 Visual Observations - General Conditions After receipt at the laboratory, sections of the-tube from Vogtle- 1-were visually-inspected to .
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| document and to identify areas of corrosion, deposits, etc. for more detailed analyses. This examination was conducted with the unaided eye and with a variable magnification stereomicroscope. Observations about tube conditions were recorded and are discussed below.
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| The conditions of regions of interest (TTS, FDB and TSP regions) were documented using low magnification digital photographs.
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| 2.2.1 RllC62 Piece 1 was entirely from the tubesheet region and had the tube pulling spike firmly attached to the inside of the tube through its bottom end. Piece 1 had many gripper marks on its outer surface and was heavily scraped, as is typical for the first piece removed from a steam generator.
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-2 Piece 2 contained the top of the tubesheet region. Piece 2 was bowed about 0.15 inch over its -17 inch length (bowed concave on the 180' side). More than 75% of the outer surface was covered with light-to-heavy fresh scrapes, making it difficult to discern the top of the tubesheet (TTS). Many gouges from the tube pulling gripper were evident. In regions without scrapes, circumferential belt polishing marks (from the tube manufacturing process) were plainly visible. No deposits were present on the tube, even in areas without scrapes. Below the TTS the OD was visibly out-of-round. An inch below the nominal location of the TTS the OD varied from 0.660" to 0.685". Above the nominal location of the TTS, the tube was round but reduced in diameter, with the OD ranging from 0.655" to 0.660" (nominal OD is 0.688").
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| Piece 3 was ovalized, bowed and heavily scratched/scraped. It had no deposits. Piece 3 did not have angled cuts, thus it was necessary to establish tube orientation. The bottom end and 0' orientation of piece 3 was identified by matching similar scratch patterns with the upper end of piece 2.
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| 2.2.2 R12C98 Piece 1 was entirely from the tubesheet region and had the tube pulling spike firmly attached to the inside of the tube through its bottom end. Piece 1 had many gripper marks on its outer surface and was heavily scraped, as is typical for the first piece removed from a steam generator.
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| Piece 2 contained the TTS region. The TTS was easily identified. The TTS had a narrow band of deposit (-0.1 inch wide) around the circumference. Above the TTS, the tube was generally in excellent condition, with only a few light fresh scrapes. The piece was not bowed, was in-round and the OD at TTS+ I" was at nominal values. There were no deposits present above the TTS and belt polish marks were clearly visible. Below the TTS, the tube had many scrapes and deep scratches, as is typical for a pulled tube. No corrosion was observed outside of the TTS region.
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| Piece 3 contained the flow distribution baffle (FDB) region. The region was easily identified as a different shade than the freespan regions of the tube. There were almost no deposits on this piece, and belt polish marks were evident. There were some shallow fresh scratches present. No corrosion was observed on this piece.
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| Piece 4 contained the first tube support plate (TSP 1) region. The region was easily identified as a different shade than the freespan regions of the tube. There were light deposits on this piece, but belt polish marks were evident everywhere, even in regions of deposits. Freespan deposits were only present (although still very light) at the 180' and 3150 orientations. There were some shallow fresh scratches present and a set of gripper marks on the TSP 1 region. No corrosion was observed on this piece.
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| Piece 5 was entirely a freespan piece. About 4-1/2" from its upper end the tube was bent by about 5'. Gray deposits were found over the piece, but belt polish marks were still evident everywhere. The deposits were somewhat thicker at the 270' orientation.
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-3 2.3 Visual Observations - R11C62 Top of Tubesheet Region
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| .Figure 2-2 shows eight views of the TTS region around the circumference of the tube. The region was heavily scraped.
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| Cracks were identified by looking in the vicinity of the nominal location of the TTS. Three axial cracks were identified with a stereomicroscope. All three cracks were at the same elevation (presumed to be close to the TTS). These were located at the 1600, 210' and 270' orientations, and were 120 mils, 100 mils and 100 mils long, respectively. These are shown in Figure 2-3. All three cracks were unbranched and were slightly off of being truly axial. The 160' crack was located in an unscraped area. The 210' and 270' cracks were located in areas that were scraped.
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| It is unusual to be able to see axial cracks in a pulled tube, even with the aid of a stereomicroscope; usually they are too tight to observe until the tube has been expanded (by internal overpressurization).
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| 2.4 Visual Observations - R12C98 Top of Tubesheet Region Figure 2-4 shows eight views of the TTS region around the circumference of the tube. The left side of each photo shows the tubesheet region of the tube; the right side shows the tube that is above the TTS. The TTS has a narrow band of deposits that are gray with some orange colored bands. The orange bands do not necessarily indicate the presence of copper, and do not have the appearance of copper that has been seen in tube deposits from other plants.
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| Cracks were identified at the TTS at the 270' orientation (see Figure 2-5). There were two circumferential cracks, 100 mils and 50 mils long, that were end-to-end with a very small separation in elevation. Other cracks may have been present, but deposits obscured their viewing.
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| 2.5 Visual Observations - R12C98 Flow Distribution Baffle Region Figure 2-6 shows eight views of the FDB region around the circumference of the tube. The region was easily identified as a different shade than the freespan regions of the tube. No corrosion was observed within the FDB region.
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| Vogtle-1 has a drilled hole flow distribution baffle plate with a nominal 0.072 inch diametrical clearance between the tube and the hole. There were no indications of contact between the tube and the FDB hole wall; there were no signs of wear, nor were there any deposits present.
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| All of the scratches shown in the figures were fresh and were thus due to the tube pull rather than installation of the tubes in the generator.
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| 2.6 'Visual Observations - R12C98 First Hot Leg Tube Support Plate Region Figure 2-7 shows eight views of the TSP I region around the circumference of the tube. The region was easily identified as a different shade than the freespan regions of the tube. No corrosion was observed within the TSP region.'
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| Receipt Inspection January 20 10 SG-CDME-09-4-NP Revision 0
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| 2-4 Vogtle- 1 has quatrefoil tube support plates with flat lands (rather than the more common concave lands). There is a nominal 0.022 inch diametrical clearance between the tube and the lands. Each land is 0.106 inch wide. Contact between the tube and one of the lands is evident in the 225' view, where there is a band of deposits that is about 0.106 inch wide. Other lands were not as obvious, indicating that the tube rested against one land.
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| All of the scratches shown in the figures were fresh and were thus due to the tube pull rather than installation of the tubes in the generator. There were no signs of wear.
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| 2.7 Dimensional Characterization The as-received lengths of the sections provided to the laboratory are summarized in Table 1-3.
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| The "Length of the Angled Cut" columns in the table refer to the axial distance covered by the cut, not the actual length of the diagonal cut (see Figure 2-1). The location of the RI 1C62 cracks was identified by microscope. The location of the TTS, FDB and TSPI regions of R12C98 were visually obvious without the aid of a microscope.
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| After initial visual inspection of the tube sections, the ends of the tube sections were squared-off and deburred to facilitate eddy current inspections. Following the eddy current inspections, the outer radii of selected sections were measured in detail. A laser micrometer was used to obtain a detailed profile of the TTS, FDB and TSP regions. Measurements were made every 0.125 inch and every 15' around the circumference of each region. Table 2-1 explains the axial coverage of the measurements for each of the four regions that were profiled.
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| Figure 2-8 presents a profile of the radii in the TTS region of R12C98. This region was nearly free of deposits and was relatively undamaged by the tube pulling process and thus represents an accurate representation of the TTS region. The profile shows no signs of any significant ovalization or denting. Figure 2-9 presents the same profile as in Figure 2-8, with the profile rotated to emphasize the expansion transition. [
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| ]a,c,e Figure 2-10 presents the radial profile of the FDB region of R12C98. This region was nearly free of deposits and was relatively undamaged by the tube pulling process and thus likely represents an accurate representation of the FDB region. The profile shows no signs of denting or ovality.
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| Figure 2-11 presents the radial profile of the TSPl region of R12C98. This region was nearly free of deposits; however this region was gripped during the pulling operation and indentations and raised metal caused by the grippers show as minor "bumps" in the profile. The profile shows no signs, of denting. There is some very minor ovality in the region (<2 mil difference between the major {60'-240°1 and minor {1500-330°} axes), which may be due to the tube gripper rather than in-generator conditions.
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| Figure 2-12 presents the radial profile of the TTS region of RI 1C62. Note that the scale has changed from the other radial profile representations. This region was heavily damaged by the pulling operation and is not representative of the TTS region. The exact location of the TTS cannot be ascertained, but the 2.25" elevation coincides with the top of the axial cracks. Most of Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-5 the radial measurements were significantly reduced from their nominal value of 0.344 inch, most likely due to the forces used in the tube pull. There are three "ridges" below the TTS, where the radii are larger than the surrounding tube. These ridges are spaced exactly 120' apart. The
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| ''valleys" between the ridges coincide with the position of gripper marks on the piece; the gripper may have caused the reduction in radius. There is some minor ovalization of the tube above the TTS (3-4 mils), with the major axis at 0°-180' and the minor axis at 90'-270'. It cannot be ascertained if any ovalization or denting was present prior to the tube pull from this profile due to the condition of the region.
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| Table 2-2 presents wall thickness measurements that were made on selected parts of both tubes prior to performing burst testing. R 11 C62 wall thicknesses have been reduced by about 2 mils, while R12C98 wall thicknesses are nominal. The reduction in RI IC62 wall thicknesses is likely due to the forces of the tube pull.
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-6 Table 2-1: Laser Micrometer Start/Stop Positions R12-C98 Pc. 2 0"=TTS, -1.0 1.0 0.125 0" @ 5.375" from bottom R12-C98 Pc. 3 0" = Center FDB, -1.375 1.5 0.125 0" @ 6" from bottom R12-C98 Pc. 4 0" = Center TSP1, -1.375 1.5 0.125 0" @ 6.75" from bottom R11-C62 Pc. 2 1.5" to 3.5" from top of 1.5 3.5 0.125 tube section Cracks @ 2-1/4" from top Table 2-2: Pre-Burst Test Wall Thickness Measurements
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| .,,'Pi.,ee,," ".'2A KP:3B" . A2.<:* 4B j TTSQI.. free~ai~ YTT S J'1fieepi Length (in) 12.13 8.15 12.63 6.25 Location of OD Measurements TTS+0.5" mid length TTS+0.5" mid length OD (0'-180') (in) 0.6505 0.6394 0.6875 0.6862 OD (90'7270') (in) 0.6564 0.6240 0.6873 0.6872 Location of Wall Thicknesses top end top bottom top end top end Approximate Location of TTS+2" TTS+l1" TTS+3" TTS+5.5" TSP1+12" Wall Thickness Measurements 0' (in) 0.039 0.038 0.038 0.041 0.040 909 (in) 0.037 --0.040- 0.038 0.041- . 0.041-1800 (in) 0.038 0.038 0.040 0.040 0.041 270' (in) 0.038 0.038 0.038 0.040 0.040 Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-7 0° 00 Bottom Top Straight Length Top Angled Length 00 9o0 Looking at Bottom End Figure 2-1: Orientation System Used in the Examination Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-8 135)
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| Figure 2-2: R11C62 TTS Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-9 1800 31-*
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| Figure 2-2: R 11C62 TTS (continued)
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-10 mm - -
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| Figure 2-3: R 11C62 TTS Cracks Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-11
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| ~i.
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| 9U' Figure 2-4: R12C98 TTS Receipt Inspection January 20 10 SG-CDME-09-4-NP Revision 0
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| 2-12 Figure 2-4: R12C98 TTS (continued)
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-13 view i View 2 Figure 2-5: R12C98 TTS Cracks Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-14 1350 Figure 2-6: R12C98 FDB Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-15 Figure 2-6: R12C98 FDB (continued)
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-16 I I- L1.%
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| 900 1350 Figure 2-7: R12C98 TSP1 Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-17
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| } Land Contact Figure 2-7: R12C98 TSP1 (continued)
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-18
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| -- a,c,e Figure 2-8: TTS Region of R12C98 Showing the Expansion Transition Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-19 a,c,e, Figure 2-9: Transition Expansion of R12C98 (Figure 2-8 Rotated)
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-20 Vogtle 12-98 Pce 3 Radius 0.3600. 0 0.3550-
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| *0.3550-0.3600 0.3500-00.3500-0.3550 Radius (in) 0.3450- 0.3450-0.3500
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| * 0.3400-0.3450 0.3400
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| * 0.3350-0.3400 03350 WT CM) C: Angular Position
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| .6 C? -O *(deg.)
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| Axial Position (in) C CD r-Figure 2-10: FDB Region of R12C98 Showing No Ovality Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-21 Vogtle 12-98 Pce 4 Radius 0.3600 0.3550-7a 0.3550-0.3600 E 0.3500-0.3550 Radius (in) 0.3450- o 0.3450-0.3500 T 0.3400-0.3450 0.3400
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| * 0.3350-0.3400 LO 0.3350 It LO 03 C Angular Position 9? (deg.)
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| Axial Position (in) ( 6 Figure 2-11: TSPI Region of R12C98. Small "Bumps" Are Attributable to Tube Pull Gripper Marks.
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| The large "bump" is likely due to raised metal near a scratch.
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 2-22 Vogtle 11-62 Pce 2 Radius 0.3550 0.35000 0.3450-
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| * 0.3500-0.3550 0.3400R ( 0.33500.34500
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| * 0.3400-0.3450 0.3350-'
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| Radius (in) 0.3350-0.3400 0.3300 0.3300-0.3350 E30.3250-0.3300 0.3250-E] 0.3200-0.3250 0.3200- *0.3150-0.3200 m 0.3100-0.3150 0.3150- t 0.3100 C1 C
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| * LOo N* Angular Position (deg.)
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| Axial Position (in) oO Figure 2-12: TTS Region of RlI1C62 (Note: Scale for radius is different from the other laser micrometer representations).
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| Receipt Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-1
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| .3.0 EDDY CURRENT TEST INSPECTION
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| -3.1 Introduction-After initial visual inspection of the tube sections, the ends of the tube sections were squared-off and deburred to facilitate eddy current inspections. Two tasks were defined for the eddy current inspections:
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| " Review and reevaluation of field data for R12C98 HL and RI1 C62 HL
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| " Acquisition and analysis of bobbin coil, +PointTM, 3Coil probe and the Ghent probe laboratory data Data are presented and discussed as appropriate to each of these tasks in the following sections.
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| 3.2 Eddy Current (EC) Data - General Practices Prior to the tube pull, the steam generator tubes were examined in the steam generator using eddy current (EC) inspection techniques. A 0.560-inch diameter bobbin probe was used as for the primary inspection and was supplemented by rotating probes where indications were identified by the bobbin coil or at the expansion transition at the TTS. The field data were reevaluated as part of the tube examination. Bobbin coil indications were identified using 160-630 kHz mix data channel from the differential mode.
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| In the laboratory, the two pulled tubes were inspected with the bobbin probe the entire length of the available tube, from just above the tube end, to where the tubes were cut. Sections of tubing containing areas of interest such as the tube support plate (TSP), the flow distribution baffle (FDB) and the top of the tubesheet (TTS), or where significant bobbin coil indications were identified, were inspected with the +PointTM, Delta and Ghent rotating probes. Data was collected at test frequencies of 10, 160, 320 and 630 kI-z for bobbin probes and at 20, 100, 200, 300 and 600 kHz for +PointTM probe.
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| The +PointTM probe contains three coils: 1) a mid-frequency +PointTM coil which forces directionality to any indication, 2) a mid-frequency 115 mil diameter pancake coil, and 3) a high frequency 80 mil diameter pancake coil. +PointTM probe indications were usually identified with the +PointTM-coil using 300 kHz-differential mode data. The-Delta probe-also consists of three -
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| coils 1) a mid frequency 115 mil diameter pancake coil similar to that in the +PointTM probe, 2) an edge mounted coilwhose axis is perpendicular to tube axis suchthat the coil is preferentially sensitive to circumferentially oriented discontinuities and 3) a second edge mounted coil whose axis is parallel to the axis of the tube such that the coil is preferentially sensitive to axially oriented discontinuities. The Delta probe was excited at frequencies of 300, 200, 100, and 10 kHz, with indications being shown for the 300 kHz responses. The third rotating probe, the Ghent probe, is a driver pick-up probe with three pancake coils mounted in an "L" pattern such that the excitation and reception using the coils on the legs of the "L" yield preferential sensitivity to axially or circumferentially oriented discontinuities. The Ghent probe was excited at 400, 300, 200, 100 and 20 kHz. Indications have been displayed using either 400 or 300 kHz responses.
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| The eddy current re-evaluation of the field data and the laboratory examinations were calibrated in a similar fashion. For the bobbin coil, the voltage for all frequency channels, except the 630 Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-2 kHz, mix and the 10 kHz channel, was set to 4.0 volts for the 20% OD calibration holes and the phase to 40 degrees for the through hole. The 10 kHz channel was set to 4.0 volts on the support ring. The rotating probe data were adjusted such that all channels except the trigger and low frequency locator channels were set to 20 volts on the through wall notch.
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| After the tubes were pulled, eddy current inspections were conducted in the Hot Cell area at the Westinghouse STD facility. The inspections were conducted with a bobbin and rotating probe configurations similar to the styles used in the field. All tube sections were inspected with the bobbin coil. The rotating probes were used only for tube sections containing the TTS or structure locations. In all cases the eddy current data were collected using an R/D Tech TC6700 and Westinghouse Anser software. The laboratory bobbin probe inspections utilized calibration standards used during the field inspection FMST-10-03 and the rotating probes used EP5-004-02 which had been used during previous Vogtle field inspections. Prior to the rotating probe examinations of the tube sections containing the tube support (TSP) crevice regions and the top of tubesheet (TTS) conductive material was attached to the outside of the tubes to act as fiducial marks in the eddy current data. The conductive material was in the shape of a large "L" with the leg nominally located at 0 degrees and the bottom portion oriented toward 90 degrees. Thus the azimuthal location of the rotating eddy current probe indications can be determined allowing the destructive examinations to be focused to the precise areas of interest.
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| Table 3-1 presents a summary of field and laboratory eddy current data obtained for the TSP crevice and the TTS regions of the pulled tubes. The laboratory data presented are for the bobbin and +PointTM probes used during the field inspection. Note that during the field inspection the TTS regions were inspected multiple times. The field results reported in Table 3-1 are for the inspection results stored on reels 45, 86 and 91. Since the results of inspections with the Ghent and Delta probes did not yield additional insight into the presence of he TTS indications beyond those of the +PointTM probe their results were not included in Table 3-1.
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| The field eddy current response of the tube support crevice regions (TSP 1 and FDB) or the free span regions below TSP2 of R12C98 HL (hot leg) and R 11C62 HL showed no indications in the field data analysis or the laboratory data review. Further, the laboratory examination found no indications in these tubing locations. In the laboratory no significant deposits were present at either the TSP 1 0rFDB region of RI 2C98. Only a-slight discoloration associated with-a-thin oxide film marked their location. This layer was not sufficient to yield an NDE response so the precise location of the intersection within the NDE data relied upon the knowledge of the physical location of the discoloration within the tube section and the NDE probe position. In the field data analysis and laboratory data review indications were noted at the TTS of both R12C98 HL and R1IC62. In the laboratory examination the eddy current response for all of the rotating probe examinations found that these indications were present and significantly increased in amplitude.
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| The following presents selected supporting eddy current data for the above observations.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-3 3.3 Field Eddy Current Test Data and Laboratory Reevaluation of Field Eddy Current Test Data for Tube R12C98 HL 3.3.1 Field Eddy Current Test Data for the TTS Region of Tube R12C98 HL The top of the tubesheet was inspected using the +PointTM probe supplemented with the Delta and Ghent probes. Figure 3-1 shows a data display for the 300 kHz +PointTM coil with the phase established such that circumferential indications produce a positive vertical defection. This channel was used in the laboratory review of the field data to size the indications (Table 3-1). The extent of cracking was determined to be 40 degrees around the circumference. Figure 3-2 shows a data display of the Delta probe response for the circumferentially sensitive coil response for the indication. Similarly, Figure 3-3 shows the Ghent probe response for the 300 kHz circumferentially sensitive coil pair.'
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| 3.3.2 Field Eddy Current Test Data for the FDB Region of Tube R12C98 HL The original bobbin field call for the region, of tube R12C98 HL at the FDB was NDD.
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| The laboratory review did not alter this conclusion; only a mix residual was identified at the TSP location (Figure 3-4).
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| 3.3.3 Field Eddy Current Test Data for the TSP1 Region of Tube R12C98 HL The original bobbin field call for the region of tube R12C98 HL at TSP1 was NDD. The laboratory review did not alter this conclusion; only a mix residual was identified at the TSP location (Figure 3-5).
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| 3.4 Field Eddy Current Test Data and Laboratory Reevaluation of Field Eddy Current Test Data for Tube R11C62 HL 3.4.1 Field Eddy Current Test Data for the TTS Region of Tube R11C62 HL The TTS was inspected using the +PointTM probe. Figure 3-6 shows a data display for the 300 kHz -PointTM coil with the phase established such that axial indications produce a positive vertical defection that was used in the laboratory review. This channel was used in the laboratory review to size the indication reported in Table 3-1. The extent of cracking was determined to be 82 degrees around the circumference. Figure 3-7 shows a data display of the delta probe response for the axially sensitive coil response for the indication. Similarly, Figure 3-8 shows the Ghent probe response for the 300 kHz axially sensitive coil pair. The laboratory review of the field response of the pancake coil response suggests rather than a single axial indication the underling response is the consequence of multiple axially oriented discontinuities. Figure 3-9 shows the pancake coil response. The characteristics of this response are consistent not only with closely spaced axially oriented discontinuities but that their axial extent on the order of the coil diameter (Reference 18).
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-4 3.5 Laboratory Eddy Current Test Data for Tube R12C98 HL The discussions that follow will center on the analysis of the laboratory eddy current results obtained with the rotating probe and bobbin coil configurations used in the field. Note that all sections of tubing had artifacts of the tube removal. The responses from these artifacts presented no issues with the analysis of the data for sections of R12C98.
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| 3.5.1 Laboratory Eddy Current Test Data for the TTS Region of Tube R12C98 HL (Piece 2)
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| In the laboratory the eddy current +PointTM response of the TTS region identified two circumferentially oriented indications. Figure 3-10 shows the circumferentially sensitive channel of the 300 kHz +PointTM response. Two circumferentially oriented indications were identified. The larger of the two is likely associated with the original field indication. The amplitude of the indication has increased in amplitude by almost an order of magnitude and grew slightly in circumferential extent. The second smaller indication not present in the field response has amplitude similar to the original field indication. The changes in the original indication, along with the presence of the new indication, are likely the consequence of the tube removal severing ligaments as the cracks opened and not the consequence of initiating new discontinuities. Visual inspection of the tube OD surface found obvious cracking.
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| Figure 3-11 shows a data display of the Delta probe response for the circumferentially sensitive coil response for the indication. Similarly, Figure 3-12 shows the Ghent probe response for the 300 kHz circumferentially sensitive coil pair. The responses of both of these probe yield results are consistent with the change in the response observed for the
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| +PointTM probe, indicating a large amplitude indication and an adjacent small indication not present in the field response.
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| 3.5.2 Laboratory Eddy Current Test Data for the FDB Region of Tube R12C98 HL (Piece #3)
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| All the inspection probes identified artifacts of the tube removal process. No bobbin coil,-
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| +PointTM, Delta or Ghent probe responses suggestive of tubing discontinuities were identified. The lack of a bobbin coil response at the FDB location suggests that field mix residual response is the consequence of the plate condition or deposits lost in the tube removal.
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| 3.5.3 Laboratory Eddy Current Test Data for TSP1 Region of Tube R12C98 HL (Piece
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| #4)
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| All the inspection probes identified artifacts of the tube removal process. No bobbin coil,
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| +PointTM, Delta or Ghent probe responses suggestive of tubing discontinuities were identified. The lack of a bobbin coil response at the TSP1 location suggests that field mix residual response is the consequence of the plate condition or deposits lost in the tube removal.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-5 3.6 Laboratory Eddy Current Test Data for Tube R11C62 HL The discussions that follow will center on the analysis of the laboratory-eddy current results -
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| obtained with the rotating probe and bobbin coil configurations used in the field. Distortion introduced into RiIC62 by the removal process was significant and precluded ultrasonic examination of the TTS region of the tube and rotating probe inspection of the tube segment above the tubesheet.
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| 3.6.1 Laboratory Eddy Current Test Data for the TTS Region of Tube RI1 C62 HL (PC#2)
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| In the laboratory, the +PointTM response of the TTS region identified axially oriented indications. Figure 3-13 shows the axially sensitive channel of the 300 kHz +PointTM response. The amplitude of the response is approximately an order of magnitude larger than the field response and the circumferential extent has increased slightly. Again-the explanation for the observed changes is a loss of ligaments within the underlying crack network rather than the creation of new discontinuities. The apparent axial extent of the indication (as measured using the +PointTM response) has decreased, however this is likely an artifact of the response of the tube distortion adjacent to the indication introduced during tube removal. The pancake coil response (Figure 3-14) shows a response similar to that in the field, suggesting that the underlying discontinuity has not changed length.
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| Figure 3-15 shows a data display of the Delta probe response for the axially sensitive coil response for the indication. Similarly, Figure 3-16 shows the Ghent probe response for the 300 kHz axially sensitive coil pair. The responses of both of these probe yield results consistent with change in response observed for the +PointTM probe.
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| One of the results for PC#2 of R1IC62 HL that was unanticipated was the bobbin coil response. Generally, the only response noted in the TTS region of the tube using the bobbin probe is the response of the expansion transition. Since this response generally overwhelms the response of degradation, it is not considered an appropriate inspection at that location. However, due to the tube distortion introduced during tube removal, the bobbin coil response did indeed yield a response consistent with degradation. Figure 3-17 shows the bobbin coil response and the measurements are included in Table 3-1.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-6 Table 3-1: Summary of Field and Laboratory Eddy Current Inspection Results Field Eddy Current Field Data Review Laboratory Eddy Current Lab Utrasonic Location Bobbin Coil +PointTM Bobbin Coil +PointTM Bobbin Coil +PointTM R12C98 TSP1 NDD NI NDD* NI NDD NDD NDD FDB NDD NI NDD NI NDD NDD NDD MCI (1380 total extent) MCI SCI 1) 0.39 V, 40%TW OD, A) Four indications w/extent:
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| 0.39 V 0.32 in length, 27' extent 140, 40, 100, 630 each N/A 40%TW GD N/A @316' azimuth location @250' azimuthal location 0.44V 0.16 in length 2) 3.09 V, 70%TW OD, spans 1120 of circumference 380 extent 2 .9V 0.25 0T in length, D 690 extent B) One indication, 70 extent
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| @247' azimuth location @740 azimuthal location R11C62 TSP1 NDD NI NDD NI Unresolved MAI Unresolved MAI SAI 0.71 V 24.9 V 6.14 V, 96%TW OD, TTS N/A SA1 0.71V N/A 92%TW OD 92%TW ID 0. 19 in length, 1330 extent NI 0.29 in length @197' azimuth location 820 extent
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| * Location determined from laboratory reference and deposit pattern (See Section 2)
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| NDD - No Detectable Degradation NI - Not Inspected N/A - Not Appropriate SCI - Single Circumferential Indication MCI - Multiple Circumferential Indications SAI - Single Axial Indication MAI - Multiple Axial Indications Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-7 Figure 3-1: Plot of the 300 Khz +PointTM Coil Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The +PointTM response is adjusted so that response from a circumferentially oriented discontinuity is in the positive vertical direction. The indication is thus interpreted as originating from a circurnferentially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-8
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| .16 1 H
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| f ~ITICI(S/SCHN~ TICK(THF7633~,TICK CH...15 SETTRIb OFF~
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| I
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| -9 TSW-IA1 35V.V I L TSH-I.14 0.A Figure 3-2: Plot of the Delta Coil Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Delta response is for the coil sensitive to circumferentially oriented discontinuities. The indication indicated by the cursor is interpreted as originating from a circumferentially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-9 TSH-l.16 351.5 Figure 3-3: Plot of the 400 Khz Ghent Probe Field Data from Vogtle Unit I SG 4 of R12C98 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Ghent response is for the coil pair sensitive to circumferentially oriented discontinuities. The indication indicated by the cursor is interpreted as originating from a circumferentially oriented discontinuity. Other responses are the consequence of deposits.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-10 Figure 3-4: Plot of the Bobbin Coil Probe Field Data from Vogtle Unit 1 SG 4 of R12C98 Showing a Response at the Hot Leg First Tube Support Plate (TSP 1).
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| January2010 Eddy Current Test Inspection Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP
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| .Revision 0
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| 3-11 Figure 3-5: Plot of the Bobbin Coil Probe Field Data from Vogtle-1 SG4 of R12C98 Showing a Response at the Hot Leg FDB.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-12 Figure 3-6: Plot of the 300 Khz +PointTM Coil Field Data from Vogtle Unit 1 SG 4 of R 11C62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The +PointTM response is adjusted so that response from an axially oriented discontinuity is in the positive vertical direction.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-13 SET TRIGOFF I AXIALAVGIF NP SLEHON l CIR STEF lAO ON AX-CIR,-COFF Figure 3-7: Plot of the Delta Coil Field Data from Vogtle Unit 1 SG 4 of R 1IC62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Delta response is for the coil sensitive to axially oriented discontinuities. The indication indicated by the cursor is interpreted as originating from an axially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-14
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| [ SICREENSETUP HUTOnA I-TR:FPOzRJ *2ý F--:* -PORL
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| # 2V Mie V 11 2: 2 6: 2
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| -* - 4 Vpp O.t5E DEG[Ox 27 1SH1 I AI TSHM1.16 0.0 T3H-I. I8 351.6 TSoH-121 A.A Figure 3-8: Plot of the 300 Khz Ghent Probe Field Data from Vogtle Unit 1 SG 4 of R 11C62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Ghent response is for the coil pair sensitive to axially oriented discontinuities. The indication indicated by the cursor is interpreted as originating from an axially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-15 Figure 3-9: Plot of the 300 Khz Pancake Coil Field Data from Vogtle Unit 1 SG 4 of R 11C62 Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The pancake response shows response characteristics consistent with short (on the order of the coil diameter) closely spaced axially oriented discontinuities.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-16 Figure 3-10: Laboratory +PointTM Coil Response from the TTS Region of R12C98 (PC#2).
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| The coil response adjusted so that circumferentially oriented discontinuities are positive direction.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3 Figure 3-11: Plot of the 300 Khz Delta Probe Laboratory Data of R12C98 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Delta response is for the coil sensitive to circumferentially oriented discontinuities. The large indication indicated by the cursor is interpreted as originating from a circumferentially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-18 13 1 11
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| : 8 6.55 II 2 480 IC6714 Vpp 2.81 DEG ",64 0x EL Figure 3-12: Plot of the 400 Khz Ghent Probe Laboratory Data from Vogtle Unit 1 SG 4 of R12C98 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Ghent response is for the coil pair sensitive to circumferentially oriented discontinuities. The indication indicated by the cursor is interpreted as originating'from a circumferentially oriented discontinuity.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-19 JICSREEN4SETUP AUTOý RKL!SOýST R STRADLUACl.dt.I, t U11 .
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| 3 023 V 8 2 V 6.16 8ii 3UD320 1 CAL 2:5 2 I PT 1_23_OF1 U.IO03 CRý2II EP4141_
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| RN1 CTCCE1C ~!c ý11OP CIRC;,ETFT A3XIRLR4GOFT UAT1si 15 quAG REPOT I REPRT SWIAE __ .. 1 .... ...__..
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| - - SPE A AI' 1011j111. I coc z"T15 al C, [ _LXCN',T[
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| Figure 3-13: Laboratory 300 Khz +PointTM Coil Response from the TTS Region of RI11C62 (PC#2).
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| Response adjusted so that axially oriented discontinuities are positive. The cursor is positioned at the axial indication.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-20 Figure 3-14: Plot of the 300 Khz Pancake Coil Laboratory Data from Vogtle Unit 1 SG 4 of R 11C62 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The pancake response shows response characteristics consistent with short (on the order of the coil diameter) closely spaced axially oriented discontinuities.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-21 I
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| Figure 3-15: Plot of the 300 Khz Delta Probe Laboratory Data of Ri11C62 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Delta response is for the coil sensitive to axially oriented discontinuities. The large indication indicated by the cursor is interpreted as originating from axially oriented discontinuities.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0 j
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| 3-22 236 8 4V 21.32 2 3 38O Khz 895 DT=(1I33',2M81jf 6S-ý.
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| I FFSET-67ý PD 86.104. 6.010, 56 2: I 2: 2 C I G3 2W3r"3 C?1,47I,819 Fri: 462665 CIFC-.61 I
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| I T101515 Ua101 ISo TICKIMI.: 1 61 2IRI-O CIRCCENT6 OFF ~C1R 360 C6 2112T86_05W CIRELillNE ýR MI131LINE O52 2331PLOT -VEV,Co DIP 05LEW, ON I
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| SET2EIfp.c flL76ý-N I 126 23I~ C6SE'I Co 1216. I~ 05051181106 6266166011813 ~6XCIRCOFF ~
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| -~ __________
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| U ___ A-..
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| _____________ 4 j Figure 3-16: Plot of the 300 Khz Ghent Probe Laboratory Data from Vogtle Unit 1 SG 4 of RI IC62 (PC#2) Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The Ghent response is for the coil pair sensitive to axially oriented discontinuities. The indication indicated by the cursor is interpreted as originating from axially oriented discontinuities.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 3-23 Figure 3-17: Plot of the Bobbin Coil Probe Laboratory Data from Vogtle Unit 1 SG 4 of R12C98 (PC#2) Showing a Response at the Hot Leg TTS.
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| Eddy Current Test Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 4-1 4.0 ULTRASONIC INSPECTION 4.1- Scope of Ultrasonic Inspections and Description-of Techniques After eddy current inspections two tasks were defined for the ultrasonic inspections:
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| * Acquisition ultrasonic data from the TSP, FDB and TTS regions of tube R12C98 and the TTS region of R 1C62 using a UTEC probe.
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| * Acquisition of ultrasonic Lamb wave data for the TTS regions of both tubes (The discussion of the Lamb wave inspection and data analysis is found in Section 5.0).
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| The sections of the Vogtle tubing were examined with a rotating multiple-element style ultrasonic probe (UTEC probe) under hot cell conditions. The probe and calibration standard used to establish system sensitivity were the same as that used to perform ultrasonic inspections in the field. The probe has three individual focused transducer elements mounted in a single probe body. The first transducer is a high frequency, spherical focused element that directs sound in the radial direction. This transducer is used for attenuation measurements and to detect thickness changes characteristic of pitting or wear damage. The second transducer is a spherically-focused search unit that directs sound around the circumference of the tube and is sensitive to radial-axial oriented discontinuities. The third transducer is spherically focused and directs sound energy along the tube axis at a 450 angle. This search unit is particularly sensitive to flaws oriented in a radial-circumferential direction. The ultrasonic transducers are interfaced to field style ultrasonic instrumentation. A Paragon (Wesdyne) ultrasonic/eddy current data acquisition system was used to collect the data. The ultrasonic portion of this system utilizes an R/D Tech 8-channel pulser-receiver and the eddy current instrument is Zetec PCI 9030 eddy current card contained in the Paragon computer chassis. Based upon the encoder output from the positioning system, data were collected at 1-degree intervals around the circumference. The system is capable of acquiring either the ultrasonic RF or rectified RF data. For this inspection only the RF data were acquired.
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| The hot cell probe delivery system consists of a mechanism to grip the UTEC probe to hold it in a fixed position. The tube sections were then mounted in a rotary table attached to a motor-driven lead screw. The rotation of the lead screw is monitored by a rotary encoder to provide axial position information of the tube section. The rotary table contains a motor, and encoder to give the azimuthal orientation of the tube section. The delivery system is interfaced to a computer which is used to control the tube location. The tube is moved rotationally and axially in a controlled manner to produce a helical motion with a pitch of 0.020 inches with respect to the UTEC probe. The computer provides trigger pulses to the Paragon data acquisition system so that the Paragon acquisition software gathers UT and EC information every one-degree around the tube circumference. A rotational speed of about 20 revolutions per minute is used during the examination. Once the data is captured, it is graphically displayed showing angular position, axial position and signal amplitude. Data from each transducer element is displayed separately for evaluation. The Paragon system allows the data to be displayed in a variety of formats. To enhance signal interpretation, color plots of where the signal amplitude determines the different colors are used in the analysis. The data is displayed showing axial and angular positions as well as signal strength for all indications.
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| Ultrasonic Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 4-2 A single reference tube standard (UE-001-96) was used to calibrate the UT system. This standard is used for setting the system sensitivity and the transducer offset, respectively.
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| In the UT analysis, a pseudo-color "C scan" plot of the data from each ultrasonic channel is presented on the computer screen and reviewed. In the discussions for the ultrasonic results that follow the data for the appropriate ultrasonic and/or eddy current channels are presented in the figures. Examples of the type of displays that are available for the three ultrasonic and eddy current channels are found in Figure 4-1. The responses displayed in this figure are for the discontinuities in calibration standard. The entire scan width represents 3600 (the circumference unwrapped) while the spacing between scan lines represents pitch (axial) travel.
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| Signals detected with the radial aim search unit (Channel 1) are measured for angular extent (ratio of the measured UT signal length to the measured length of a 360' scan multiplied by 3600). The axial UT length is obtained by counting the scan lines and multiplying by the inspection pitch. These functions are performed automatically by the Paragon software. Data interpretation and flaw characterization is accomplished by reviewing the displays of each transducer. The displays are compared and conclusions drawn concerning the characteristics of the discontinuity detected. By which transducer a discontinuity is detected has a significant implication related to the orientation of the discontinuity. The radial-aim search unit is designed to be sensitive to planar discontinuities such as wastage and pitting. Experience has shown that this search unit can also detect IGA (intergranular attack) and, in rare instances, measure the radial depth of cracks. The circumferential-aim search unit is sensitive to radial-axial discontinuities such as OD stress corrosion cracks and can be used to measure the axial extent of a wastage edge. The axial-aim is excellent for the detection of OD radial-circumferential cracking and can be used to measure the circumferential extent of a wastage edge.
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| 4.2 Laboratory Ultrasonic Inspection Results The UTEC probe was inserted into the tube from the bottom of the tube sections with the section moved so that the effective motion of the probe was toward the top of the tube. Table 3-1 presents a summary of key UT observations for the Vogtle tubing. The areas of interest were the TSP, FDB and TTS of R12C98 HL and the TTS of RI 1C62 HL. Unfortunately distortion of the tube during tube removal prevented the UTEC probe from being inserted into the tube section containing the TTS of R 11C62 HL. Prior to the UTEC inspection, addition conductive "L"s were added to the OD of the tube sections that was to be traversed by the UTEC eddy current coil to assure that the orientation of the UTEC probe could be verified. Indications of tubing discontinuities were found only in the TTS section of R12C98. Ultrasonic indications that are known to be from scratches as a result of the tube pulling or loose debris is identified as spurious are observed in all of the inspection channels. Only responses believed associated with tube degradation have been noted in the images. Ultrasonic indications believed to be relevant are further evaluated. The results of inspections of that tube section will be discussed in the following paragraphs.
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| 4.2.1 Laboratory UT of Tube R12C98 HL in the TTS Region The TTS region of R12C98 HL is contained in piece 2. The ultrasonic data displayed numerous responses originating from both inside and outside of the tube. Figure 4-2 Ultrasonic Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 4-3 shows a display of theultrasonic response from piece 2 in the laboratory. The results from the various transducers, including the eddy current response, are presented as color C-scans: The-cursor was placed at the location of the primary indication: The response .
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| from the transducer looking for circumferential discontinuities finds one large indication and a number of shorter indications separated by ligaments. These smaller indications have been highlighted with arrows. Even within the large indication there are variations in response that are suggestive of ligaments having been present prior to the tube removal but that have been severed. The radial looking transducer also detects the presence of the discontinuity as loss in response from the OD of the tube. This is not unexpected when discontinuities are open and penetrate the wall by more than 60%. Further, the location of the indication is just inside the transition in tube diameter on the inside of the tube, placing the indication at approximately the tangent point of the tube with the tubesheet on the outside of the tube.
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| Other indications in the response from the circumferential sensitive transducer are observed at the same elevation as the primary indication. These indications are on the OD of the tube and were initially believed to be associated with deposits adherent to the OD of the tube, however upon review it was concluded that at least the indication located at 74 degrees originated from possible degradation.
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| Many indications are observed in all the inspection responses. These indications are both ID and OD in origin and are believed artifacts of the tube removal process. Further the conductive "L" denoting the location of the azimuthal 0 degree location and the direction of angular measurement is readily observable in the eddy current response.
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| Ultrasonic Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 4-4
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| ~~~1~~ 7i~1 7641t464-ii77 )ým77 S-mmC Jnimfi W116 Is F-M Figure 4-1: UTEC Response to Calibration Standard UE-001-96.
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| C-scans are shown for all ultrasonic transducers and also the 300 kHz pancake eddy current coil.
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| Ultrasonic Inspection January 2010 SG-CDME-09-4-NP Revision 0
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| 4-5 Figure 4-2: Laboratory UTEC ultrasonic results for the TTS region (Piece 2B) of R12C98 HL.
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| The four C-scan displays are for the radially looking transducer (upper left), axially looking transducer looking for circumferentially oriented discontinuities (upper right), the circumferentially looking transducer looking for axially oriented discontinuities (lower left) and the 300 kHz pancake coil eddy current response (lower right). The lower portion of all the displays is toward the bottom of the tube. The cursor in each of the images indicates the location of the primary circumferentially oriented indication. To the left as indicated by the arrows are secondary circumferential indications consistent with the location of the +PointTM response. To the right in upper right and lower left displays are indications consistent with shallow OD degradation or deposits. The arrow to the right side of the upper right image is a possible circumferential indication not identified by the +PointTM inspection. Other indications are from the presence of the tube removal artifacts on the tube OD and ID.
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| 5-1 5.0 PSEUDO LAMB WAVE UT TECHNIQUE 5.1 - Introduction-.. ...
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| The destructive examination of steam generator tubes removed from Vogtle Unit 2 (Reference 6) failed to identify degradation associated with eddy current indications that had raised concern for the presence of circumferential cracking. The conclusion of the investigation was instead that eddy current indications at the expansion transition originated from unique characteristics of the deposit morphology. Consequently methodologies were sought that could discriminate this circumstance from tubing degradation. One such approach was an alternate ultrasonic test using Pseudo Lamb waves.
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| Pseudo Lamb waves (modes of ultrasonic energy propagation) occur when the dimensions of the structure in which the sound is propagating are smaller than the wavelength of the sound in the bulk material. Under these circumstances the bulk shear, longitudinal and surface mode are mixed together to yield responses in many different modes. Some of the Lamb waves (modes) interact only weakly with material on the surface and offer the possibility of being immune to the presence of surface deposits on the tube. Thus, the use of Lamb waves opens the possibility that a technique that interacts with the underlying tubing degradation and not with the surface deposit can be implemented.
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| The Lamb wave inspection was conducted on the TSP 1, FDB region and the TTS region of tube R12C98. The inspection of the TTS region of RI IC62 had also been planned, however, the distortion of the tube section as a result of the tube removal process prevented the probe from being inserted and scanned within the tube section.
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| 5.2 Equipment A probe was designed to excite the appropriate Lamb mode in the tube. The probe consists of a spring loaded wedge that contacts the inside surface of the tube (Figure 5-1 and Figure 5-2). The underside of the wedge has a taper machined into it, towhich the ultrasonic transducer is mounted. The angle that the taper is machined determines the angle the sound wave will impinge the inside of the tube and, therefore, which Lamb mode will be launched. When the probe is inserted into the tube, the wedge is ultrasonically coupled to the tube by filling the tube with water. This particular probe was found to yield the best separation between tubing discontinuities and simulated deposits when it was excited with a tone burst of a specific frequency (3.04 MHz).
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| Under these conditions only a limited number of modes are excited, yielding the enhanced response characteristics. However, the probe still provides reasonable separation between deposits and discontinuities if excited by a broad frequency spike pulse. Under these conditions care must be exercised in analyzing the data so that the appropriate mode is extracted from the response.
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| The Lamb wave inspection was conducted using the same test set-up, calibration tube and data acquisition system as used for acquiring the UTEC data. After recording, the data were displayed with the Paragon analysis software.
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| 5-2 5.3 Results
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| -Prior to the inspection of the tube-sections the probe-was put into the- scanner-and data acquired from the calibration tube. Figure 5-3 shows the C-scan response usingthe Lamb wave probe.
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| The C-scan was generated with the gate set so that the measured response originates from the Lamb wave rather than a bulk mode. By gating at a different time the response from the bulk mode can be displayed. Thus a comparison between the bulk response and the Lamb wave response is possible within one inspection.
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| 5.3.1 Laboratory Lamb Wave UT of Tube R12C98 HL in the TTS Region The ultrasonic data displayed numerous responses originating from both inside and outside of the tube. Figure 5-4 shows a display of the ultrasonic response from piece 2 in the laboratory. The C-scan results from gating the response corresponding to the Lamb mode in Figure 5-4. The response finds one large indication possibly showing evidence of where ligaments had been lost and a shorter indication separated by ligament. This smaller indication has been highlighted with the black arrow. An additional indication highlighted with the blue arrow is the remaining response from tube removal artifact on the outside of the tube. The remaining responses that had been found with the UTEC probe and were believed associated with OD deposits do not yield a Lamb wave response.
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| 5-3 Wedge/Transducer Centering Device Figure 5-1: Ultrasonic Contact Probe for Launching Lamb Waves from the Inside of the Tube.
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| Figure 5-2: Photograph of the 3.5 MHz Lamb Wave Probe Compatible with the UTEC System.
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| Pseudo Lamb Wave UT Technique January 20 10 SG-CDME-09-4-NP Revision 0
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| 5-4 Figure 5-3: Lamb Wave Response of Calibration Tube UE-001-96 Pseudo Lamb Wave UT Technique January 2010 SG-CDME-09-4-NP Revision 0
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| 5-5 j /f/!D/W imD MJ,1J U."i ýM 5.b rj j qm As ZW F L A Figure 5-4: Plot of the Lamb Wave Response of Vogtle Unit 1 SG 4 of R12C98 (PC#2)
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| Showing an Indication at the Hot Leg Top of Tube Sheet (TTS).
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| The black arrow indicates a discontinuity response separated from the main indication.
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| The blue arrow indicates a response from a tube removal artifact.
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| Pseudo Lamb Wave UT Technique January 2010 SG-CDME-09-4-NP Revision 0
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| 6-1 6.0 DEPOSIT PH The purpose of this test was to determine if the crevice-chemistry was highly acidic or highly.
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| caustic.
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| Prior to sectioning the tube, a quick screening test was performed on the remaining deposits that adhered to both TTS regions, the FDB and TSP region of R12C98, and a region of thin freespan deposits located on the uppermost part of piece 5 of R12C98. This test simply involved wetting a piece of pH paper with deionized water and pressing it against the deposits of interest. The resulting color change in the pH paper, if any, was then compared with the color chart that came with the paper.
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| In all cases, the pH paper indicated a neutral pH.
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| 7-1 7.0 BURST TEST The primary purpose of the burst testing was to determine if the degraded tube sections exceeded the NEI 97-06 requirements on burst strength (Reference 19), implemented by EPRI guidelines (Reference 26). The most limiting requirement is that the tube must sustain three times normal operating pressure differential (3NOP) without burst. 3NOP is approximately 3915 psi for Vogtle-1 (Reference 20) at temperature, or 4597 psi for room temperature testing {temperature correction factor of 1.14 to account for higher material strength of 11/ 16" A600TT at room temperature, multiplied by a gage uncertainty factor of 1.03 (Reference 21). Lubricated foil was used during the burst test, thus the 3NOP target pressure did not require an additional correction factor (Reference 22).}
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| 7.1 Sample Preparation In preparation for eddy current testing, and subsequent burst testing, the TTS regions were sectioned into foot long samples, with the TTS region centered as well as possible across the length. The TTS region from R 1C62 was included in a 12-1/8 inch long sample (section 2A),
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| with the TTS region located 9-1/4 inches from the bottom of the sample. The TTS region from R12C98 was included in a 12-5/8 inch long sample (section 2A2), with the TTS region located 5 inches from the bottom of the sample.
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| Freespan sections were also burst tested, so as to determine the burst pressure of an unflawed section from each tube. The freespan burst test sample from RI IC62 (piece 3B) was 8.15 inches long (located 3.18 to 11.33 inches above the TTS). The freespan burst test sample from R12C98 (piece 4B) was 6.25 inches long (located 6 to 12.25 inches above TSP1).
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| In addition, a dummy piece was burst test to check for proper operation of the equipment. All equipment was found to be working properly. The results of the dummy sample are not included in this letter report.
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| The diameters and wall thicknesses of each sample were measured after cutting. These are presented in Table 2-2.
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| All of the pieces from tube R 11C62 were deeply scratched and the diameter had been reduced from the tube pulling process. The tubesheet region of R12C98 was also misshaped as part of the normal process to release the hydraulic expansion of the tube from the tubesheet prior to pulling the tube. The condition of these regions of tubing would not allow Swagelok fittings to form a leak-tight seal, thus two inch long extensions of Alloy 600 tubing were butt welded onto affected ends of these samples. This included both ends of the TTS and freespan samples from R1IC62 and the lower (tubesheet) end of the TTS sample from R12C98.
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| During welding of the extensions onto the ends of the samples, thermocouples were placed on the TTS regions to monitor how much weld heat was transferred to the crack region of the tube.
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| Temperatures at the TTS regions did not exceed 300'F at any time during the welding.
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| 7-2 Swagelok fittings were then affixed to the extensions, or directly on the tube ends that did not require extensions. One end of each sample had a fitting that allowed pressurized room temperature nitrogen or waterto pass into the sample from a 1/8 inch diameter supply line.-
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| 7.2 Leak Screening 7.2.1 Purpose To determine if a leak path had developed through the tube wall, each TTS region was screened for leakage. For each section with a TTS region, mechanical fittings were swaged onto the ends and room temperature, low pressure bottled nitrogen was fed to the inside of the tube. The sample was then held under deionized water for observation of leakage. The leak screening was performed without fixtures that simulate the constraints of TSP intersections.
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| 7.2.2 Results The TTS region of R12C98 did not leak when pressurized to 500 psi. Higher pressures were not attempted so as not to damage the crack prior to burst testing.
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| The TTS region of R 11C62 showed large leakage when pressurized to 90 psi. This was about the lowest pressure that could be reliably regulated with the available regulator.
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| Leakage was observed from two locations, 160' and 270', as a continuous stream of bubbles. Considering the 8-10 fold increase in ECT voltages from the in-generator to the lab testing, the visually observed crack, and the lack of large leakage while this tube was still in the generator, it was concluded that this magnitude of leakage was not representative of in-generator conditions and that the tube pulling operation had significantly altered the leakage characteristics of RI IC62.
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| Elevated temperature testing was not conducted (Reference 23). Leak screening demonstrated that R12C98 would not have leaked. Unusual circumstances for R11C62 included:
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| " NDE examinations had shown a ten-fold increase in RPC voltage. A factor of two or less is typical. A factor often increase was observed in the Sequoyah-2 pulled tubes (Reference 24), which had been damaged by pull forces well in excess of the yield strength of the material.
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| * Also, visual observations demonstrated that the cracks were plainly visible with the aid of a low power microscope. Typically, axial cracks in pulled tubes are tight enough so that they cannot be observed, up to a magnification of 50x. Like the Vogtle- 1 cracks, axial cracks in the Sequoyah-2 tubes were also visible by stereomicroscope.
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| Westinghouse had recommended against elevated temperature leak testing. Reasons cited included:
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| 7-3
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| : 1) The samples were no longer representative of their in-generator condition, nor are the cracks representative of service-induced ODSCC cracks. Relating leak test results to ECT data would be problematic. .
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| : 2) Elevated temperature leak test results would be erroneous. There would be a risk that the data would be misused for any future databases for A600TT tubing. Such a case was made to the NRC in regards to the Sequoyah-2 pulled tubes (Reference 24).
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| : 3) The high temperature water and high velocity fluid flow through the crack during an elevated temperature leak test would compromise any crack surface chemistry information that might be obtained.
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| SNOC agreed with Westinghouse's recommendation.
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| 7.3 Burst Test Set-Up Room temperature burst tests were performed in accordance with the Reference 25 procedure and the Reference 26 guidelines using a system separate from the leak screening system. The pressurized water for the burst test was supplied by a large volume, piston delivery system.
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| Pressure was increased and supplied to the sample with a single, controlled stroke of the piston.
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| The rate of movement of the piston was fixed so as to increase the rate of pressurization at 20-500 psi/second. The internal pressure of the specimen was recorded digitally through a data acquisition system and by an analog X-Y recorder. It was also monitored by analog gages as a back-up.
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| One of the TTS regions demonstrated that it had a throughwall leak path, and the other was judged to have a significant chance of premature leakage. To complete a valid burst test on the TTS regions, it was necessary to cover the potential source of leakage with a bladder (to prevent leakage during pressurization) and foil (to prevent the compliant bladder material from being forced through the crack). A length of Tygon tubing, used as the bladder, and a 0.006 inch thick brass foil, cut to 1.0 inch wide by 1.75 inches long, were inserted into the specimen with the foil placed over the largest ECT indication. The foil was lubricated using stopcock grease.
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| Bladder and foil were not used on either freespan sample. The freespan samples were not tested with restraints.
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| The TTS regions were laterally restrained by a support system designed to simulate the conditions in the Vogtle-1 steam generators under accident conditions, Figure 7-1 shows a sketch of the accident conditions that were approximated. Under accident conditions, secondary side pressure is released and the primary side pressure pushes the tubesheet upward. It is assumed that the tubes are not locked into the supports. Tubes thus follow the deflection of the tubesheet and are likewise pushed upwards. The support structures are assumed to remain stationary. The deflection of the tubesheet causes the tubesheet hole near the top of the tubesheet to dilate (it likewise contracts on the bottom of the tubesheet). Tubesheet hole dilation reduces or eliminates contact pressure between the tube and the tubesheet and thus the point at which the tubesheet provides support to the tube moves deeper into the tubesheet. The upper support simulant and tubesheet simulant were placed in positions relative to the TTS on the sample to approximate Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-4 these conditions. While the precise positions of the supports were not determined for accident conditions, the positions used were conservative for the goal of simulating lateral support to the cracks at the TTS. .
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| To provide the lateral support to the crack that is provided by the combination of the tubesheet and the first support structure above the tubesheet, an unpressurized extension of tubing was attached to the upper end of each TTS sample. A welded cap was attached to each sample; the cap both sealed the upper end of the sample and attached the sample to the extension, thus adding several feet to the sample's length. The upper end of the extension passed through a support simulation while the sample itself passed through tubesheet simulation. There was clearance between the extension and the support, allowing the extension to slide through the support. The tube sample was tightly clamped into the tubesheet simulation and was not allowed to slide.
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| For the TTS region of R 1 C62, the top of the TTS support was located an inch below the TTS.
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| The upper support (simulating the TSP) was centered 38 inches above the TTS (which was 39 inches above the TTS support) and provided a 0.022-0.026 inch diametrical clearance with the extension. For the TTS region of R12C98, the top of the TTS support was also located an inch below the TTS. The upper support (simulating the FDB) was centered 18.4 inches above the TTS (which was 19.4 inches above the TTS support) and provided a 0.060-0.080 inch diametrical clearance with the extension.
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| Tape with a known composition was applied to the TTS regions prior to burst to catch any deposits that might have flaked off during testing. The intent was to collect deposits for chemical analysis by X-Ray Diffraction (XRD); however, after the burst tests there was an insufficient amount of deposit on any tape sample for XRD.
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| 7.4 Burst Test Results The freespan samples were burst test before the TTS regions to get a better idea of the possible burst pressure ranges and to establish how the tube pulling operation may have affected R1IC62.
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| The RI IC62 freespan sample burst at 12,150 psig during the first attempt,- however the burst occurred in the extension that had been welded to the bottom of the sample and was thus not a valid burst test of the material. Thus a second burst test was conducted on the same sample.
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| The burst extension was cut off and a fitting welded directly to the sample. Support collars were placed over the weld heat affected zones to prevent bursts from occurring in regions of tube that experienced stress relief from the weld heat. The second burst test of the RI IC62 freespan produced a valid axial fish mouth burst at 12,525 psig.
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| The R12C98 freespan sample burst at 11,250 psig. The burst was an axial fish mouth burst near the middle of the sample length.
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| The TTS region of R12C98 burst at 10,725 psig. The burst was a circumferentially oriented burst that occurred at the TTS, approximately at the 2400 orientation.
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| 7-5 The TTS region of R 11C62 burst at 10,800 psig. Taking the ratio of the freespan bursts (11250/12525 = 0.898) as a correction factor for the effects of the pulling operation, gives a burst pressure of 9700 psig for the in-generator condition of the cracks.-The sample had an axial fish mouth burst that occurred at the 160' orientation.
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| The burst test results are included in Table 7-1. All burst pressures were more than twice the 3NOP criteria of 4597 psig and thus did not represent a safety issue while in the generator.
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| 7.5 Calculated Burst Pressure The EPRI Flaw Handbook (Reference 27) provides equations that can be used to estimate the burst pressure. The equations can be used with length and depth data obtained from eddy current testing, or the more accurate laboratory testing. A burst pressure estimate using eddy current data is representative of the practice used by the industy when pulling a tube is not practical. A burst pressure estimate using lab data is performed to demonstrate the conservatism of the equations.
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| Calculated burst pressures are summarized in Table 7-2.
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| 7.5.1 Rl1C62 Axial Cracks The eddy current examination did not identify the axial cracks in R 11C62 to be throughwall, while the laboratory examination determined that all three cracks were throughwall (Table 9-3).
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| For the RI IC62 axial cracks, the equation for part-throughwall axial cracking was used with the eddy current data:
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| PB = 0.58D(SY + Su)-i t .104- L Lt hi (1)
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| Where:
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| PB = burst pressure L = crack length Ri= inner radius of the tube t = wall thickness of the tube Sy = yield strength Su = ultimate strength h relative effective structural depth = d/t = effective structural depth / wall thickness (1- 1 for OD cracking The 1R14 condition monitoring report used a length of 0.18 inch and a depth of 77%TW for the R1IC62 indication (Reference 12). For the case where eddy current data is used, the yield strength (46 ksi) and ultimate strength (102 ksi) of Heat 2272 were used (see Section 1.3). Using a nominal wall thickness of 0.04 inch and a nominal inner radius of 0.304 inch, a burst pressure of 6448 psi is obtained.
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| 7-6 For the RI 1C62 axial cracks, the equations for freespan throughwall axial cracking were used with the laboratory data. The EPRI Flaw Handbook (Reference 27) provides equations for TTS cracks as well, but the freespan condition is more conservative. It was assumed that the 1600 crack dominated the burst pressure, as it was the crack that actually burst, and only a single crack is considered. For freespan throughwall axial cracking:
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| PBRm PN (Sy+ S)t L
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| R1t (2)
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| PN =b, +b 2 exp(b 3k) bi = 0.061319 b2= 0.53648 b3 =-0.2778 Where:
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| PB = burst pressure PN = normalized burst pressure L = crack length R, = mean radius of the tube t = wall thickness of the tube Sy = yield strength Su = ultimate strength For the case where lab data is used, the yield (49.2 ksi) and ultimate (104.5 ksi) strength of R12C98 was used, as it is reasoned that it is similar to that of R 1IC62 (see Section 11.1). A crack length of 0.1 inch is conservatively used as an approximation of the throughwall crack length of the 160' crack (see Figure 9-15). Using a nominal wall thickness of 0.04 inch and a nominal mean radius of 0.324 inch, a burst pressure of 9139 psi is obtained.
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| The longer crack length of the eddy current data causes its estimate of burst pressure to fall below that of the lab data; however, both estimates are conservative in comparison to the actual results by a large margin.
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| 7.5.2 R12C98 Circumferential Cracks For the circumferential crack in R12C98, the equation for circumferential cracking with restricted lateral tube motion (Reference 27) was used:
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| P Rt (S, + S, X0.57326- 0.35281ý)
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| RB
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| ,n Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-7 Where:
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| PB burst pressure Rn = mean radius of the tube t = wall thickness of the tube Sy = yield strength Su = ultimate strength
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| = percent degraded area (PDA) / 100 The 1R14 condition monitoring report used an eddy-current-based PDA of 7.3 for the R12C98 indication (Reference 12). For the case where eddy current data is used, the yield strength (46 ksi) and ultimate strength (102 ksi) of Heat 2272 were used (see Section 1.3). Using a nominal wall thickness of 0.04 inch and a nominal mean radius of 0.324 inch, a burst pressure of 10004 psi is obtained.
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| For the case where lab data is used, the measured yield (49.2 ksi) and ultimate (104.5 ksi) strength of R12C98 was used (see Section 11.1). A measured PDA of 21 is used (see Section 9.5). Using a nominal wall thickness of 0.04 inch and a nominal mean radius of 0.324 inch, a burst pressure of 9472 psi is obtained.
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| Both of these estimates are conservative in comparison with the measured burst pressure of 10725 psi.
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| 7.5.3 Freespan Tubing The freespan section that was burst tested from R1 1C62 had been subjected to tube pull forces above the yield strength of the material, thus any estimations of burst strength would be lower than the actual burst strength of 12525 psi. Comparisons are thus only valid for the burst test of the freespan section of R12C98. For freespan thin-walled tubing, the equation for uniform thinning (Reference 27) was used, with no thinning applied:
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| P3 = 0.598(S, + Su ) t Rm Where:
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| PB = burst pressure Rm = mean radius of the tube t = wall thickness of the tube Sy = yield strength Su = ultimate strength For the case where an estimate is needed without the benfit of a direct measurement, the yield and ultimate strengths of Heat 2272 (46 ksi and 102 ksi, respectively) were used (see Section 1.3). For the case where lab data is used, the yield and ultimate strengths of R12C98 (49.2 ksi and 104.5 ksi, respectively) were used, as it is reasoned that it is similar to that of both tubes (see Section 11.1). Using a nominal wall thickness of 0.04 inch and a nominal mean radius of 0.324 inch, a burst pressure of 10926 psi is obtained for Sy+SU =
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| 148 ksi and 11347 psi for Sy+Su = 153.7 ksi. The first estimate is conservative in Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-8 comparison to the freespan burst test of R12C98. The second estimate is an excellent estimate of the burst pressure and the difference is less than 100 psi (0.8%).
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| 7.6 Post-Burst Observations Table 7-1 presents a summary of the post-test measurements made on the burst test samples.
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| Figure 7-2 through Figure 7-5 present photos of the burst openings. Tearing was confirmed by microscope for all four cases, thus (in accordance with Reference 26 criteria) each burst test was considered a valid burst test.
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| Each burst test sample was viewed under a stereomicroscope around its entire circumference in the vicinity of the burst. No corrosion or cracks were observed on either freespan sample.
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| 'The TTS region of RI 1C62 was viewed using a stereomicroscope, including the three axial cracks that had been observed in the as-received condition (see Section 2.3). These were located at the 1600, 2100 and 270' orientations. The only other area of corrosion that was observed was a possible small patch of intergranular attack (IGA), located next to the 1600 crack. These observations are shown in Figure 7-6 and photos are shown in Figure 7-7.
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| The 270' crack on R 1IC62 had closed shut from the burst test and was difficult to view from the outer surface of the tube. However, it was easily seen from the inside of the tube. The TTS region was. clamshelled, in preparation for sectioning the individual cracks for scanning electron microscopy (SEM). The photograph in Figure 7-8 clearly shows that all three cracks had penetrated throughwall and were located at about the same elevation.
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| The TTS region of R12C98 was also viewed using a stereomicroscope and as many as eight regions of circumferential cracks and possibly one very short (15 mil) axial crack was observed.
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| The one crack that had been observed in the as-received condition (see Section 2.4) was located at the 270' location, which was part of the burst opening. The observedlocation of crack is provided in the sketch in Figure 7-9, and photographs of the circumference are provided in Figure 7-10.
| |
| In preparation for the SEM examination, The TTS region of R12C98 was pulled apart. Figure 7-11 shows a photo of the TTS cracks in cross-section. In the photo, the view is up the tube, thus azimuthal locations are clockwise from the location where 00 is indicated. Cracks were found around most of the circumference, as is shown by the brownish areas.
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-9 Table 7-1: Post-Burst Measurements Tube ~R11C62 R.R1 IC62* k2C918 1 9R12C98~
| |
| Piece 23B2A24B Region ;TTS fr n T >p Burst Pressure (psig) 9700** 12525 10725 11250 Burst Orientation axial axial circumferential axial Pressurization Rate (psig/sec) 187 188 182 185 7.15" above 2.94" above Location of Burst TTS bottom weld e TTS boto bottom bottom Azimuthal Location of Burst 1600 80 0 2350-2800 2250 Length of Burst Opening (in) 1.259 1.407 0.425 1.425 Width of Burst Opening (in) 0.293 0.222 0.030 0.268 Maximum Diameter (in) 0.830 0.780 0.770 0.966 Diameter, 900 from Maximum (in) 0.698 0.662 0.744 0.820
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| * = Results of second burst test.
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| ** = Corrected for effects of tube pull (see Section 7.4)
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| Table 7-2: Calculated Burst Pressures Pi~~ A: 3B ZA-2* `4 Re TTS feespan. T I espan Calculated Burst Pressure using field data (psig) 6448 10926 10004 10926 Calculated Burst Pressure using lab data (psig) 9139 11347 9472 11347 Burst Test January 2010 SG-CDME-09-4-NP Reision 0
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| 7-10 a aIc,e Figure 7-1: Burst Test Support Simulation.
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-11 Figure 7-2: Burst Opening at R 11C62 TTS (at 160' Orientation).
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-12 Figure 7-3: Burst Opening at R 11 C62 Freespan (at 80' Orientation).
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-13
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| _.__" From Weld CGnt Bottom Figure 7-4: Burst Opening at R12C98 TTS (at 240' Orientation).
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| Burst Test January 2010 January 2010 SG-CDME-09-4-NP Revision 0
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| 7-14 Figure 7-5: Burst Opening at R12C98 Freespan (at 225' Orientation).
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| January 20100 Revision Burst Test January 20 10 SG-CDME-09-4-NP Revision 0
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| 7-15 TTS+1.5" TTS+I" IGA?
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| TTS+0.5" TTS TTS-0.5" I
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| TTS- ]"
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| TTS-1.5" 0o 90O 1800 2700 3600 Burst at 160° Crack at 2100 Crack at 2700 Figure 7-6: Post-Burst Observations on R1IC62 Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-16 2f U Crack Closed Figure 7-7: R 1 C62 TTS Post-Burst Close-Up Views Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-17 Figure 7-8: ID View of R 11C62 TTS Region Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-18 TTS+1.5" 650 Possible circ cracks TTS+ 1" 90'- 100' Circ cracks 1350 Circ crack with short axial crack 160' Possible short axial crack -15 mils long TTS+0.5" 1 TTS - -. 0-ftmo-p- -
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| TTS-0.5" 1 1800 Circ crack 2250 Circ crack 235'- 2800 Burst opening and circ crack TTS-1" 2850 Circ crack 3150 Circ crack TTS- 1.5" 0o 900 1800 270' 360' Figure 7-9: Post-Burst Observations on R12C98 Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-19 Figure 7-10: R12C98 TTS Post-Burst Close-Up Views Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 7-20 2 /U_ 315' Figure 7-10: R12C98 TTS Post-Burst Close-Up Views (continued)
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 7-21 Figure 7-11: Circumferential Cracks at the TTS of R12C98 (view = up)
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| Burst Test January 2010 SG-CDME-09-4-NP Revision 0
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| 8-1 8.0 SECTIONING
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| -Figure 8-1 -through Figure 14 show where selected pieces from both pulled-tubes and the archived tubing were obtained. The table below summarizes the cutting diagrams:
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| Table 8-1: Cutting Diagrams Figur Qjkn Diagrai J ; -j-ýK 8-1 R 11C62 Section 1 (not sectioned) 8-2.
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| 8-2 Cutting Diagram for R 11C62 Section 2 (Post-Burst Test) 8-3 8-3 R 11C62 Section 2A Cutting and Examination Plan 8-4 8-4 Cutting Diagram for R 11C62 Section 3 (Post-Burst Test) 8-5 8-5 R 11C62 Section 3B Cutting and Examination Plan 8-5 8-6 R12C98 Section 1 (not sectioned) 8-6 8-7 R12C98 Section 2 (Post-Burst Test) 8-7 8-8 R12C98 Section 2A2 Cutting and Examination Plan 8-8 8-9 Cutting Plan for R12C98 Section 3 (for Eddy Current Testing) 8-9 8-10 Cutting Plan for R12C98 Section 3 8-10 8-11 Cutting Plan for R12C98 Section 4 8-11 8-12 Cutting Plan for R12C98 Section 5 8-12 8-13 R12C98 Section 5A Cutting Diagram and Examination Plan 8-13 8-14 Archive Tubing Cutting and Examination Plan 8-14 Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-2 Section 1 - 6.5" (7.125" total)
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| Figure 8-1: R 11C62 Section 1 (not sectioned)
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| Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-3 TTS+1.5" TTS+Il" TTS is 9.25" from bottom TTS+0.5" of section 2A
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| +
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| TTS TTS-0.51 Section 2A- 12.125" (Burst Test) TT11S-I" TTS-1.5" 90o 270' 360o Burst at 160' Crack at 270' Crack at 2100 Section 2B - 4.56" Section 2C - 0.75" Figure 8-2: Cutting Diagram for RI 1 C62 Section 2 (Post-Burst Test)
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| Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-4 Step Instructions I Cut Section 2A2 as shown at burst opening tips Section 2A4 - 1.5" 2 Make cut B first (at about 0°)
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| 3 Photo ID side of cracks and TIG pass 2A3: 4 Make cut A. Make cuts close to 2100 crack tips.
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| Section 2A3 - 0.5" Use pliers to separate 2A2A OD Surface Roughness (X-Y) then 5 Make cut C. Make cuts near the 270' crack tips.
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| Modified Huey The OD side of the crack (which is difficult to I
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| see) is likely to be longer than the ID side, so Section 2A2 - 1.5" 2A2: stop cuts 1/8 inch from ID crack tips. Use pliers to separate 2A2C and 2A2D See diagram below:
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| cracks Section 2AI - 8.5" 00 900 1800 270' 3600 2A2B: 2A2D 2A2R1 (unner): - Archive
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| - ID Surface roughness (X-Y) 2A2C (270' Crack):
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| - Transverse view - SEM depth profile (photomontage) of axial crack - SEM/EDS fracture face (metallography) - SEM/EDS OD surface and deposits
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| - Microhardness 2A2A (1600 Crack)
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| - SEM depth profile (photomontage)
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| - SEM/EDS fracture face
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| - SEM/EDS OD surface and deposits
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| -2A2A (2100 Crack)
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| SEM depth profile (photomontage)
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| SEM/EDS fracture face SEM/EDS OD surface and deposits Figure 8-3: R 11 C62 Section 2A Cutting and Examination Plan Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-5 I
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| Section 3B - 8.15" (Burst Test)
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| Section 3A - 0.3" Figure 8-4: Cutting Diagram for R 1I C62 Section 3 (Post-Burst Test)
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| Section 3B5 - 3" I 3B3A:
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| Archive 3B4:
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| Section 3B4 - 0.5" Modified Huey 3B3:
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| Section 3B3 - 0.5" See Diagram at Right 900 Section 3B2 - 2" 3B2:
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| Bulk Chem 3B3B:
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| Microstructure (Longitudinal)
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| Microhardness Section 3BI - 2" Figure 8-5: RI 1C62 Section 3B Cutting and Examination Plan Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-6 Section I -5.0" (5.625" total)
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| Figure 8-6: R12C98 Section 1 (not sectioned)
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| Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-7 Section 2D --0.75" TTS+1.5" TTS+I" TTS 10.5" TTS is 5.03" from bottom of section 2A2 TTS TTS-0. 5' Section 2A2 - 12.625" (Burst Test)
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| TTS-11" TTS-1.5"L
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| : 0. 90, 1800 2700 360' 650 Possible circ cracks 901- 100, Circ cracks 135' Circ crack with short axial crack 1600 Possible short axial crack -15 mils long Section 2AI - 0.25" 1800 Circ crack 225' Circ crack 235'- 280' Burst opening and circ crack 285' Circ crack 315' Circ crack Section 2B - 9.625" Figure 8-7: R12C98 Section 2 (Post-Burst Test)
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| January 20100 Revision Sectioning January 20 10 SG-CDME-09-4-NP Revision 0
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| 8-8 Section 2A2F - 2.6" Archive Step Instructions I Measure position of TTS 2 Scrape remaining deposit from OD (XRD) 3 Pull circ crack apart 2A2E:
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| Section 2A2E - 0.5" Modified Huey 4 Take macro pix of crack 5 2A2C: Do SEM work first before any cutting Section 2A2D - Archive 2.2" to 2.5" 2A2C:
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| : 1. SEM depth profile (photomontage)
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| Section 2A2C - 0. 5" 2. SEM/EDS fracture face
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| : 3. SEM/EDS OD surface and deposits TTS (pull apart 2A2) 4. Possible MET mount for axial cracks Section 2A2B - 0. 5" 2A2B:
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| See diagram below:
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| TTS TTS-0.5"
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| : 0. 360' Section 2A2A - 5.75" (see 2A2B4) 2A2B1 2A2B3 2A2B4
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| - Archive - Longitudinal - Archive mount for metallography of circ crack
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| -Microhardness 2A2B2
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| - Transverse mount for metallography of axial cracks Figure 8-8: R12C98 Section 2A2 Cutting and Examination Plan Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-9 Section 3E -0.75" Section 3D - 5.313" Section 3A- 12.125" (contains FDB)
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| Section 3B - 5.813" Section 3C - 0.75" Figure 8-9: Cutting Plan for R12C98 Section 3 (for Eddy Current Testing)
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| Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-10 Section 3E - 0.75" Section 3D - 5.313" Section 3A- 12.125" (contains FDB)
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| Section 3B2 3B2:
| |
| Residual Stress 2.2" to 2.5" Section 3B1 -3.3" Section 3C - 0.75" Figure 8-10: Cutting Plan for R12C98 Section 3 Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-11 Section 4C - 0.75" I Section 4B - 6.25" (Burst Test)
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| Section 4A - 12.5" (contains 01 H)
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| Section 4D - 0.75" Figure 8-11: Cutting Plan for R12C98 Section 4 Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-12 Section 5C - 2" (EPRI sample)
| |
| Section 5A - 21" (3.125" above bend)
| |
| (16.875" below bend)
| |
| Section 5B - 0.75" Figure 8-12: Cutting Plan for R12C98 Section 5 Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| 8-13 5A5A:
| |
| ID/OD Surface Roughness (X-Y)
| |
| Section 5A5 - 0.5" 5A5:
| |
| See Diagram at Right 00ý-
| |
| 90° S5A4:
| |
| Section 5A4 Residual Stress then 2.2" to 2.5" Bulk Chem 5A5B:
| |
| 5A3 - I" Microstructure (Longitudinal)
| |
| Section e region bend ionMicrohardness ..
| |
| Section 5A2 - 12" 5A2:
| |
| Tensile Test 5
| |
| 5AIB:
| |
| Section 5AI B - 0.5" Modified Huey Section 5A IA -4.2" Figure 8-13: R12C98 Section 5A Cutting Diagram and Examination Plan Sectioning January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 8-14 XA4A:
| |
| ID/OD Surface Roughness (X-Y)
| |
| Section XA5 0.5" XA4: 00fý Section XA4 - 0.5" See Diagram at Right 90, SectionXA3 - 0.5" XA3:
| |
| Modified Huey p537 XA2:
| |
| Residual Stress XA4B:
| |
| Section XA2 -2.1" then Microstructure (Longitudinal)
| |
| Bulk Chem Microhardness Section XAIB 4.75" Section XAI - 9.5" XA 1:
| |
| Tensile Test K Section XAIA 4.75" Figure 8-14: Archive Tubing Cutting and Examination Plan Sectioning January 2010 SG-CDM E-09-4-NP Revision 0
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| | |
| 9-1 9.0 FRACTOGRAPHY Samples-2A2A (1600 and 2100 cracks) and 2A2C (270' crack) from-tube RI IC62 (see Figure-8-3), as well as sample 2A2C (upper half of circ crack) from tube R12C98 (see Figure 8-8) were examined in detail by scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) in conjunction with the SEM. The SEM/EDS examination included depth profiling, ligament sizing, opened crack fractography, and a semi-quantitative elemental analysis of the crack surface and OD deposits.
| |
| 9.1 Procedure Each sample examined by SEM/EDS was blown with a jet of dry oil-free air to minimize non-conductive particulates from the fracture surfaces that would otherwise collect an electrical charge (and thus hinder the view) during the SEM examination. Observations made during the SEM examination were documented photographically. Operation of the SEM/EDS followed the manufacturer's instruction. ASTM has not published procedures for fractography examinations.
| |
| However, surfaces examined by SEM in accordance with accepted scientific principles and EPRI guidelines can be compared with fractographs presented in various fractography textbooks, such as "Metals Handbook, Volume 12, Fractography", 9th Edition, American Society of Metals, 1985. EDS spectra were analyzed using a standardless semi-quantitative algorithm.
| |
| SEM fractographs were taken of the entire fracture surface of each burst opening that had corrosion at approximately 75X. These fractographs were taken with secondary electron and back-scattered electron SEM. These fractographs were then aligned end to end to complete a photomontage of each crack surface. The depth of the corrosion was measured at selected intervals, providing a set of depth vs. axial location measurements. The depths were converted to percent throughwall (%TW) values by dividing by the depth measurement at a completely throughwall location.
| |
| Uncorroded ligaments were sized in terms of length, area and axial location. Ligaments were characterized as "in-plane" (the face of the ligament running parallel with the crack face) or "out-of-plane" (running perpendicular to the crack face), depending on which direction most of the ligament area was oriented.
| |
| Fractographs were taken of selected locations at magnifications up to 1OOOX to characterize the surface of the crack. The elemental composition of selected areas on the crack and OD surface were analyzed by EDS.
| |
| Figure 9-1, Figure 9-2 and Figure 9-3 show low magnification views of the three axial crack samples, showing the cracks with different methods (secondary electron SEM, backscattered electron SEM and optical). The crack surface of the circumferential crack that was shown by the optical photo in Figure 7-11 is shown in four parts by secondary electron SEM in Figure 9-4.
| |
| 9.2 Crack Surface Characterization Figure 9-5 presents an example of the crack surface at a higher magnification view, taken near the crack tip of the R 11C62 160' crack. The fractograph shows that the corrosion was Fractography January 20 10 SG-CDME-09-4-NP Revision 0
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| | |
| 9-2 intergranular, as was shown by the rock candy topography. Ductile tearing is seen in the region with the dimpled surface; this represents the part of the tube wall that did not crack while in-service-but rather was brought to tensile failure during the burst test and/or the tube pulling operation. The distinction between what part of the ductile tear region is due to the tube pull and what part is due to deliberate actions in the laboratory cannot be made.
| |
| Figure 9-6 presents an example of the crack surface of the R 1I C62 2100 crack. Figure 9-7 presents an example of the crack surface of the RI IC62 270' crack. Figure 9-8 presents several examples of the crack surface of the R12C98 crack.
| |
| All of the corrosion on all four cracks was intergranular; there was no evidence of transgranular cracking.
| |
| 9.3 EDS Analysis of Crack Surfaces EDS analyses were performed on selected areas of each crack. Figure 9-9 presents an example of one of the areas that an EDS analysis was performed, in this case the middle of the crack surface of the R1IC62 1600 crack. The fractograph in the upper left shows the general area that was examined. The fractograph in the upper right shows the area on which the EDS analysis was performed. The spectrum is the result of the EDS analysis.
| |
| Several areas on each of the four cracks were examined by EDS. In addition to crack surfaces, the ductile region was examined by EDS so as to obtain spectra of the base metal and to confirm that sample handling did not introduce elements to the crack surface. Table 9-1 provides a summary of the crack surface EDS results.
| |
| The four crack surfaces have approximately the same composition. Ratios of Ni:Cr are very consistent in all of the areas examined and are close to the values of Ni:Cr that are found within the base metal. This suggests that conditions within the crevice were not grossly acidic or caustic. The sampling depth of EDS is on the order of 100 times larger than typical crack surface oxides and thus the base metal composition overwhelms the oxide composition. The chemical cleaning also likely affected the crack surfaces, removing any deleterious compounds that may have been present during crack initiation.
| |
| The crack surfaces themselves seem to be free of sulfur, lead or copper, elements that have been associated with some instances of cracking in mill annealed Alloy 600. There was some sulfur in areas that had a deposit on the crack surface, and its absence from deposit-free regions suggests that the sulfur is associated with the deposit. Figure 9-10 shows an example of crack surface deposit. The deposit itself does not seem to originate from laboratory handling, as sulfur and any evidence of deposit is absent from ductile surfaces. It cannot be determined if the deposit migrated into the crack or if it formed within the crack during operation. There is 2-3 times as much silicon on the mid-crack regions as there is at the crack tip.
| |
| These results do not provide data that can be used to assess the cause of the cracking in the TTS regions; the chemical cleaning has likely removed any evidence of what chemical compounds may have contributed to cracking.
| |
| Fractography January 2010 SG.CDME-09-4-NP Revision 0
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| | |
| 9-3 9.4 SEM/EDS Analysis of OD Surfaces and Deposits The OD surfaces of three-regions-near theTTS cracks were examined by both SEM and EDS.
| |
| These include samples 2A2A and 2A2C from RI IC62 (see Figure 8-3), and the 315' region of sample 2A2C of R12C62 (see Figure 8-8).
| |
| Figure 9-11 shows the OD surface of the TTS of R 11C62, between the 160' and 210' orientations. The axial cracks are located near the mid-length of the sample. Most of this part of the surface has a light scrape along its length, but the left side of the sample is unscraped and shows belt polish marks. Located at the 1650 orientation, about 0.7 inch below the 160' crack were two short shallow axial cracks (see Figure 9-12). These are located within the scraped part of the surface. A closer view of the cracks shows that they are due to intergranular corrosion.
| |
| There were also several small patches of IGA next to and close to the 160' crack; these are shown in Figure 9-13. The OD surface of RI IC62 sample 2A2C was heavily scraped over its entire OD surface and showed no cracks.
| |
| Figure 9-14 shows the OD surface of the TTS of R12C98, near the 315' orientation. The figure shows the opened circumferential crack near the bottom of the upper picture, spotty deposits and IGA. Circumferential belt polish marks are also visible. The patches of IGA correlate with the deposits. There was no cracking or IGA above the deposits.
| |
| EDS analyses were performed on selected areas of the OD surfaces. The results are summarized in Table 9-2. Sulfur, lead, chlorine and copper were identified on these surface, but generally in small quantities. Copper was only associated with R12C98 and lead was only associated with Ri11C62. Lead and sulfur were found on scraped surfaces, implying that they were introduced during or after the tube was pulled from the generator. Phosphorus was only associated with R12C98.
| |
| 9.5 Depth Profiles Following the completion of burst testing, one face from each of the three axial cracks was sectioned from the TTS of RI 1C62 and the entire TTS region of R12C98 was opened by application of a tensile load. The corrosion depth and position in each region was characterized.
| |
| by Scanning Electron Microscopy (SEM).
| |
| Longitudinal sections were removed from R1 IC62 using a diamond tipped cutting wheel and each was blown with a jet of dry oil-free air to remove any particulates from the fracture surfaces to minimize charging during the SEM examination.
| |
| Operation of the SEM followed the manufacturer's instruction. ASTM has not published procedures for fractography examinations. However, surfaces examined by SEM in accordance with accepted scientific principles and EPRI guidelines can be compared with fractographs presented in various fractography textbooks, such as "Metals Handbook, Volume 12, Fractography", 9th Edition, American Society of Metals, 1985.
| |
| A series of fractographs were taken of the entire fracture surface of each burst opening that had corrosion at approximately 75X. These fractographs were then aligned end to end to complete a Fractography January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 9-4 photomontage of each crack surface. The depth of degradation was measured at small intervals on each montage using a calibrated scale that is part of the SEM instrument's software. These measurements were then divided by the magnification to obtain the defect-depth, divided by the pre-burst measured wall thickness (Table 2-2) to obtain the fraction throughwall, and then multiplied by 100 to obtain the percent throughwall. Areas that were 100% throughwall (1 00%TW) were assigned a value of 100%TW after a review of the photomontage to ensure that it was indeed throughwall..
| |
| Figure 9-15 through Figure 9-17 show the depth profiles of the three axial cracks from the TTS of RI1 C62. Figure 9-18 shows the depth profile of the cracks around the circumference of R12C98.
| |
| Table 9-3 provides a summary of the depth profiles for RI IC62. All three cracks were OD initiated and were 100%TW. The 2100 crack was the largest crack of the three, but because it was between the other two cracks it apparently was subjected to a lesser hoop stress than the other two cracks, thus the burst occurred in the larger of the two other cracks.
| |
| The TTS of R12C98 contained approximately 31 individual cracks. The maximum depth was 80%TW (at the 2330 orientation). The cracks have a percent degraded area (PDA) of 21%. The longest individual crack was 920 (from the 181'° to the 2730 position). The longest undegraded extent was 80 (from the 1420 to the 1500 position), although most of the circumference was less than 10%TW.
| |
| Fractography January 20 10 SG-CDME-09-4-NP Revision 0
| |
| | |
| 9-5 Table 9-1: Summary of EDS Analyses Performed on Crack Surfaces
| |
| - ~ ~~~~~~ ] b~k E'4:~~
| |
| m~LSEenita1 ~nmposition (W't%)K<
| |
| Ciackn,,
| |
| jTDe0::iioi/< jCAA~~ J g ]'Al j a~ F Cr ý'iýMi [ Fe VNi Deposit onCrack 4.660 30.216 0.409 4.798 10.169 1.999 2.345 1.877 27.428 !16.100 RI1C62 160, Mid-Crack 3.943 11.179 0.490 1.965 0.391 12.353 0.278 8.656 60.746 Crack-Tip 2.402 5.832 0.489 0.501 0.253 14.359 0.136 8.982 67.045 Ductile 1.286 2.161 0.425 0.268 0.227 14.683 0.062 8.982 71.906 Mid-Crack 3.786 11.169 0.298 1.651 0.191 13.449 9.962 59.495 RllC62 210o Deposit on Crack 5.659 43.706 0.600 5.902 11.020 0.404 1.742 1.889 1.271 21.013 6.795 Crack-Tip 3.478 6.200 0.383 0.692 13.923 0.088 8.979 66.256 Ductile 2.171 2.169 0.349 0.275 14.699 0.093 9.252 70.991 Mid-Crack 3.825 7.749 0.420 1.026 0.343 12.952 0.136 8.711 64.838 RllC62 270' Crack-Tip 1.729 3.267 0.369 0.352 0.207 14.379 0.493 8.967 70.236 Ductile 1.717 2.305 - 0.495 0.483 0.279 14.544 0.047 9.348 70.781 125' Mid-Crack No Deposit 4.606 9.798 0.475 1.664 0.340 13.384 0.096 8.727 60.910 R12C98 125' Mid-Crack Some Deposit 7.872 27.521 0.507 8.391 0.251 0.170 8.730 0.118 6.799 39.640 Ductile 4.177 3.050 0.314 0.513 0.313 14.145 0.087 8.770 68.632 Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-6 Table 9-2: Summary of EDS Analyses Performed on OD Surfaces Bare Surface Unscraped 3.056 3.305 0.317 0.340 0.255 14.283 0.113 8.942 69.390 Bare Surface Unscraped Near IGA 4.457 31.914 0.846 1.582 0.257 7.343 0.280 31.469 20.067 1.785?b RllC62 Bare SurfaceUnscrapedNearIGA 47.685 33.693 0.248 1.940 8.152 0.668 2.522 0.737 0.005 1.136 2.749 0.465 2A2A Deposit Near IGA 2.358 29.490 0.058 0.583 1.543 0.283 11.923 0.273 9.876 41.259 0.161 2.193 Pb Bare Surface UnscrapedNearIGA 15.021 34.351 0.719 5.881 6.535 0.386 0.598 2.959 0.513 21.335 11.701 Scraped Surface Near Small Cracks 5.008 1.516 0.135 0.204 11.709 0.856 7.534 41.200 41.837 0
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| Scraped Surface Near 27 ' Crack 8.597 6.535 0.502 0.772 0.499 0.246 0.354 11.561 0.060 13.624 56.089 1.161 Co 0.349 0.175 2.888 1.258 2.313 0.029 58.465 20.011 11.0920Co Ri1C62 Scraped Surface Near 270' Crack 2.679 0.740 2A2C Scraped Surface Darker Area 14.409 46.651 0.236 8.880 9.874 0.472 0.626 0.854 0.395 9.426 7.305 0.345 0.095.K Scraped Surface Darker Area 8.040 30.295 1.605 2.249 0.372 0.268 9.371 0.173 14.011 32.012 1.605.Pb Scraped Surface Near 270' Crack 6.168 3.500 0.408 0.942 1.843 0.161 0.928 5.736 0.007 39.201 34.095 7.011 Co Deposit 18.899 29.480 0.300 1.026 7.774 0.381 0.794 0.135 4.703 0.378 0.958 0.271 29.842 3.138 0.781 0.687 0.454 Cd R12C98 Heavy Deposit 18.605 33.841 2.426 5.504 10.630 0.150 0.791 0.051 3.628 0.152 1.092 3.140 15.264 4.029 0.458 0.237 2A2C Light Deposit 3.641 34.293 0.468 1.365 0.154 0.260 2.390 0.528 48.041 7.764 1.098 Oxide 0.25 inch Above Crack 5.218 32.453 0.248 0.890 0.208 0.399 17.868 0.726 17.919 23.562 0.508 Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-7 Table 9-3: Summary of RI IC62 Depth Profiles
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| ,Cra&kLocation 4! ,,hk, (Azimutiall.f ,* <>::::
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| . ... Positlon)... iin)i <gtifir Maximum Depth 4 : :.:(°TW): [[ , oengtOf IOOMTW*I hin-),i;:
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| C,'i..:1?2::rhdck 1600 0.142 100 0.073 2100 0.123 100 0.093 2700 0.124 100 0.035 Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-8 Secondary Electron Back-Scattered Electron Optical View Figure 9-1: Overall Views of R 1 C62 1600 Crack (Sample 2A2A)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-9 Secondary Electron Back-Scattered Electron Optical View Figure 9-2: Overall Views of R 1C62 210' Crack (Sample 2A2A)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-10 Secondary Electron Back-Scattered Electron upticai view Figure 9-3: Overall Views of R 11C62 270 Crack (Sample 2A2C)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-11 31S me Figure 9-4: Secondary Electron SEM View of R12C98 Crack Surface Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-12
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| / 135
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| *0 Figure 9-4: Secondary Electron SEM View of R12C98 Crack Surface (Continued)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-13 na Figure 9-4: Secondary Electron SEM View of R12C98 Crack Surface (Continued)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-14
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| /I A Ductile Tearing Intergranular Corrosion 500X Figure 9-5: R 11C62 160' Crack - Crack Tip Example by SEM Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-15 500X Figure 9-6: R 11C62 2100 Crack Example by SEM 75X Figure 9-7: RI 1C62 270' Crack Example by SEM Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-16 Part Throughwall Crack at 390' Location - 150X Deep Crack at 125" Location - 150X Deep Crack at 1200 Location - IOOOX Figure 9-8: R12C98 Crack Examples by SEM Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-17 M
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| 3050-w 1
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| Cr 1
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| wi Si Ce 0 1 2 3 4 5 6 7 8 9 keV Figure 9-9: Example of EDS Analysis of Crack Surface (R I C62 1600 Crack - Mid-Crack)
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| Figure 9-10: Example of Crack Surface Deposit for EDS Analysis (R I C62 1600 Crack)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-18 Figure 9-11: OD Surface of Ri1IC62, Between 1600 and 2100 Orientations (Sample 2A2A)
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| Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-19 Figure 9-12: Small Axial Cracks at the 1650 Orientation Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-20
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| 'Ih~
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| Figure 9-13: IGA Near R 1IC62 1600 Crack Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-21 Figure 9-14: Region Above R12C98 Circ Crack, Showing IGA and Deposits Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-22 100 90 80 70 60 50 40 30 20 10 0
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| 0 20 40 60 80 100 120 140 Axial Position From Bottom (mils)
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| Figure 9-15: Depth Profile of Rl1C62 TTS Crack at 1600 Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-23 100 90 80 70 60 50 40 30 20 10 0
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| 0 20 40 60 80 100 120 Axial Position From Bottom (mils)
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| Figure 9-16: Depth Profile of R 1IC62 TTS Crack at 2100 Fractography Januhry 2010 SG-CDME-09-4-NP Revision 0
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| 9-24 100 90 80 70 60
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| '-50 40 30 20 10 0
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| 0 20 40 60 80 100 120 Axial Position From Bottom (mils)
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| Figure 9-17: Depth Profile of Ri11C62 TTS Crack at 270' Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 9-25 100 90 80 70 60 C-50 40 30 I
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| 20 10 0
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| 0 50 100 150 200 250 300 350 Azimuthal Location (Degrees)
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| Figure 9-18: Depth Profile of R12C98 TTS Cracks Fractography January 2010 SG-CDME-09-4-NP Revision 0
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| 10-1 10.0 METALLOGRAPHY OF CRACKS 10.1:.. Procedure ..
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| Samples 2A2B1 from R 11C62 and 2A2B2 from R12C98 were mounted to show a transverse section for examination of axial cracks by metallography. Sample 2A2B3 from R12C98 was mounted to show a longitudinal section for examination of circumferential crack by metallography (Table 10-1).
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| The metallographic samples were mounted in epoxy to show cracks in cross-section. Each mounted sample was ground with SiC papers, followed by diamond wheels using polishing oil, followed by diamond aerosol sprays, leaving the edge to be examined with a mirror finish.
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| Samples were then examined and photographed after an electrolytic Nital etch. The electrolytic Nital etch was used to highlight the relationship between the cracks and the grain boundaries.
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| 10.2 RllC62 Axial Crack Figure 10-1 shows a cross-sectional view of the 1600 opened crack. A view of the crack near the OD surface is shown at a higher magnification. Figure 10-2 shows a view of the crack near the ID surface. All of these views show a crack that is intergranular and is unbranched. There was no transgranular cracking. There are elongated grains near the ID surface, indicating that the crack was not entirely throughwall at this cross section and there was some tensile failure near the ID surface where the crack had not grown through.
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| Figure 10-3 shows a cross-sectional view of an unopened crack at the 145' location. This crack is also intergranular and is 13%TW at this cross-section. It is somewhat branched.
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| 10.3 R12C98 Axial Crack Two possible short axial cracks (<0.15 inch long) were identified during the post-burst visual examination. Metallography was conducted to confirm/document these cracks. At the 1600 orientation (Figure 10-4) there were two areas that appear to be a part of the circumferential crack extending into this particular cross section. Due to the short length of the axial crack that was identified by visual means, the axial crack was not captured in a transverse section, thus the 1600 axial indication was not confirmed (nor denied) by metallography.
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| Figure 10-5 shows an axial crack at the 135' orientation. An unusual set of circumstances is shown in the figure. It appears that there is a shallow axial crack that is 4%TW, but it is undercut by a part of the circumferential crack that has extended into the cross section shown. The circumferential crack is 20%TW in this view.
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| 10.4 R12C98 Circumferential Crack Figure 10-6 shows a cross-sectional view of the opened circumferential.crack. A view of the crack near the OD surface is shown at a higher magnification. Figure 10-7 shows a view of the crack near the ID surface. All of these views show a crack that is intergranular and is unbranched. There was no transgranular cracking. There are elongated grains near the ID Metallography of Cracks January 20 10 SG-CDME-09-4-NP Revision 0
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| 10-2 surface, indicating that the crack was not entirely throughwall at this cross section and there was some tensile failure near the ID surface where the crack had not grown through.
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| Metallography of Cracks January 2010, SG-CDME-09-4-NP Revision 0
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| 10-3 Table 10-1: Metallography.Samples
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| >i...j K Ekanýitksd f E*'lrsnetd fore1/2 E.
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| Tube- JSectioinM'unt*j View f C*io..fks'e :"Referencii R 11C62 2A2B1 M2871 Transverse x x Figure 8-3 RI IC62 3B3B M2872 Longitudinal x Figure 8-5 R12C98 2A2B2 M2873 Transverse x x Figure 8-8 R12C98 2A2B3 M2874 Longitudinal x x Figure 8-8 R12C98 5A5B M2875 Longitudinal x Figure 8-13 Archive XA4B M2877 Longitudinal x Figure 8-14 Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-4 Figure 10-1: R 1IC62 1600 Crack- OD View Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-5 4 mils Figure 10-2: RI IC62 1600 Crack- ID View Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-6 l 5mils Figure 10-3: R 1IC62 1450 Crack- OD View Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-7 I 5 mils
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| /
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| 1 5 mils Figure 10-4: R12C98 Cracks at 1600 Seen in a Transverse Section Axial cracks not shown. The face of the circumferential crack is shown directly on in this transverse section, but the face of the circ crack is just outside this transverse plane.
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| Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-8 5 Mils Circumferential Crack, Seen "directly on" in this Transverse Section Figure 10-5: R12C98 Axial Crack at 1350 The figure shows a transverse section taken near the plane of the circumferential crack. A shallow axial crack (- 4 grains deep) is seen near the OD surface. A part of the deeper circumferential crack is also shown in this transverse section, appearing as a "hole" that undercuts the axial crack. A portion of the face of the circumferential crack is within the blurred part of the "hole."
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| Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-9 Figure 10-6: R12C982 Circ Crack at 270 - OD View Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 10-10 Figure 10-7: R12C982 Circ Crack at 270'- ID View Metallography of Cracks January 2010 SG-CDME-09-4-NP Revision 0
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| 11-1 11.0 MATERIAL CHARACTERIZATION
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| -11.1- Tensile Test The tensile properties of R12C98 were determined by a room temperature tensile test of a full cross section tubular specimen; approximately 12 inches in length, which was removed from section 5A (see Figure 8-13). A similar test was performed on a section of archive material from the same heat of material as R 1IC62 and R12C98 (see Figure 8-14). A tensile test was not performed on R 1I C62 because the tube had been exposed to forces above the yield strength of the material during the tube pull and would thus provide misleading results, and insufficient material was available to conduct a test on a full cross section.
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| Both full cross section tubular specimens were fitted with snug-fitting stainless steel plugs (mandrels) machined in accordance with ASTM Standard Method E8. A crosshead speed of 0.1 inch/minute was used during testing.
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| Figure 11-1 provides the stress-strain curve from the tensile test of R12C98. The material in R12C98 had a yield strength of 49.2 ksi and an ultimate strength of 104.5 ksi. Figure 11-2 provides the stress-strain curve from the tensile test of archived material from Heat 2272. The material in the archived tube had a yield strength of 47.0 ksi and an ultimate strength of 102.1 ksi. This compares well with CMTR data that indicates that the heat has a yield strength of 46 ksi and an ultimate strength of 102 ksi.
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| 11.2 Bulk Chemistry The chemical composition of the base metal of the tube was determined by quantitative chemical analysis of a one inch section from both pulled tubes and archived material from Heat 2272. The radioactivity of each section was reduced by several cycles of immersion in a room temperature solution of 35% HN03 + 4% HF (by volume), plus surface abrasion with silicon carbide wheels.
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| Quantitative analysis was performed using a combination of x-ray fluorescence, inductively coupled plasma, inert gas fusion, and combustion methods (Reference 28).
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| The results of the chemical analyses are provided in Table 11-1. The composition of the tube is within the limits set by specification SB167-A02. R 1IC62 and R12C98 have nearly identical compositions, supporting the records that indicate that they were from the same heat of material.
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| Heat 2272 was very similar to both pulled tubes.
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| The carbon content of the pulled tubes was 0.033 wt%, a moderate level of carbon, but considerably higher than the archived material.
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| For comparison, the composition of one of the tubes pulled from Vogtle-2 is included (Reference 6). It had a carbon content that was similar to the Vogtle-1 pulled tubes.
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| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| 11-2 11.3 Microstructure Analysis 11.3.1. -Procedure - -. .
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| The microstructure of the pulled tubing was examined to determine the grain size and the general distribution of the carbide precipitation. Table 10-1 presents a summary of the samples that were examined for microstructure.
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| Samples were etched in a 5% Nital solution and examined by optical microscopy for grain size rating per the comparison method of ASTM E 112. The comparison method uses a template that is based on measurements made at a magnification of IOOX (for Alloy 600TT). For measurements made at other magnifications, a factor is added to the result to obtain the ASTM grain size:
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| Q = 2 LOG 2 (M/100) = 2 LN(M/100) / LN(2)
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| Samples were examined for carbide precipitation by SEM following polishing and etching in a 2% bromine-methanol solution. This examination method reveals both carbides and grain boundaries at the same time, allowing for a direct assessment of the amount of grain boundary carbide precipitation and the level of intragranular carbides.
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| 11.3.2 Grain Size Figure 11-3 shows an example of the microstructure after a Nital etch. This sample was 2A2B1 from R 11C62, taken near the TTS. It is shown at a magnification of 1000X. Thus the correction factor is Q=6.64. Comparisons made with the ASTM E 112 template show that the grains were an even mix of 3. and 4 sized grains. Taking the average, adding the correction for magnification and rounding yields an ASTM grain size of 10.
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| Table 11-2 presents a summary of the measured grain sizes. Paxit (Version 7.1) is a graphics storage program that has a grain sizing function. The grain sizes, as determined by Paxit, are also included in the table for comparison, but are presented for information only...
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| The microstructure is characterized as having a fine grain size, in the range ASTM size 9-
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| : 10. The fine grain size also suggests a lower temperature mill anneal. The microstructure exhibited some variety of grain sizes but did not exhibit and banding of small grains, which would be typical of low temperature mill annealed Alloy 600 (A600MA) with grains in the ASTM size 10-12 range. The archive tubing has larger grains, ASTM size 8, which is more representative of A600TT tubing in Model F steam generators. The pulled Vogtle-2 tubes had grain sizes of 8 and 9 (Reference 6).
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| 11.3.3 Microstructure Figure 11-4 shows the carbide distribution and grain boundaries from R1IC62 near the TTS. Four locations are shown at higher magnification. The microstructure shows a Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| 11-3 relatively low density of grain boundary carbides for A600TT and a relatively high density of intragranular carbides.
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| Figure 11-5 shows the microstructure of R 11C62 in a location remote from the TTS. It has a similar microstructure to that near the TTS.
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| Figure 11-6 and Figure 11-7 shows the carbide distribution and grain boundaries from R12C98 near the TTS. Figure 11-8 shows the microstructure of R12C98 in a location remote from the TTS. These microstructures are all similar to that of R 11C62.
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| Figure 11-9 shows the microstructure of archived Heat 2272 material. In contrast to the pulled tube microstructures, the archived material shows a high density of grain boundary carbides, sometimes referred to as a continuous network of carbides. There are relatively few intragranular carbides.
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| Figure 11-10 shows the microstructure of tube R12C59, pulled from Vogtle-2 in 2004 for a TTS indication (Reference 6). The indication for this tube was found to be false, and no corrosion has found on the tube. The microstructure of the Vogtle-2 tube also shows a high density of grain boundary carbides and relatively few intragranular carbides.
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| In contrast, Figure 11-11 shows the microstructure of a pulled from Seabrook in 2002 for a TSP axial indication (Reference 4). The Seabrook tube was found to have an axial crack at the location of the indication. The Seabrook microstructure shows a random distribution of carbides and no correspondence with grain boundaries.
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| The low density of intergranular carbide precipitation suggests that the mill annealed treatment was ineffective in dissolving sufficient carbon and carbides. As was seen in Section 11.3.2, the material has a fine grain size; the fine grain sizealso suggests a lower temperature mill anneal. If the final mill anneal temperature is too low, the cold-worked grains will recrystallize but the carbides present from prior thermal processing will not dissolve. This will inhibit grain growth, producing a fine grain structure, and also on cool down there will be relatively little carbon available to precipitate on the new grain boundaries. Without sufficient carbon in solution, intergranular carbides- cannot -
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| precipitate during the thermal treatment. Precipitation occurs on undissolved, intragranular carbides.
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| Material with an elevated resistance to stress corrosion cracking tends to have low strength, coarse grains, few intragranular carbides and a semi-continuous to continuous network of intergranular carbides.
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| 11.4 Microhardness Testing 11.4.1 Procedure Microhardness tests are used to provide information such as general hardness, verification of specific heat treatment, random hardness variations, and hardness gradients caused by localized cold work.
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| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| 11-4 The Vickers hardness measurements were performed in accordance with Westinghouse Procedure-MR 9111 Rev- 1. Vickers hardness is determined by dividing the applied-kg-force load by the surface area of the indentation in square millimeters, computed from the mean of the measured diagonals of the indentation. A 500-g load was used for the measurements on a polished transverse cross-section.
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| Six sets of microhardness measurements were obtained: one from archived material and 2-3 from each of the pulled tubes. For each pulled tube, a sample was chosen near the TTS and another was chosen in a location remote from the TTS. For tube R12C98, two sets of microhardness traverses were obtained from the TTS region.
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| 11.4.2 Results Figure 11-12 and Figure 11-13 show the microhardness results. Four of the five traverses that were performed on pulled tubes show the effects of exposure to forces above the yield strength of the material. Tube R 11C62 was exposed to high tube pull forces and specimens from both tubes were exposed to elevated pressures (and thus plastic expansion of the tube diameters) as part of the burst test. These samples show elevated microhardnesses due to the cold work from the pull forces and burst pressures.
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| One sample from R12C98 and the archived tube sample were not exposed to either of these forces. These are shown in Figure 11-13. Both of these tube show no signs of cold work in general, nor are there any signs of cold work near the ID or OD surfaces.
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| For comparison, Seabrook measurements are included (Reference 4) for information only. The Seabrook microhardnesses were made with a Knoop indenter and a conversion (http;//www.leco.com/resources/met tips/met tip9.pdf) was necessary-to estimate what their values might be with a Vickers indenter. The Seabrook tube shows elevated microhardness at the OD surface when compared to the middle of the tube. The Seabrook tubes had elevated residual stresses and this trend may be an artifact.
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| 11.5 Sensitization Assessment 11.5.1 Procedure During the manufacture of the tube, carbon that has been dissolved during the final mill annealing operation, and has been retained in solid solution, precipitates to form (primarily) intergranular chromium carbides. Short-range diffusion of chromium to the boundaries to effect the precipitation of intergranular M 2 3 C 6 can result in a Cr-depleted region adjacent to the grain boundaries. This condition is typically referred to as "sensitization", and is a condition that renders the material susceptible to intergranular attack in aggressive oxidizing chemical environments (but not generally in PWR primary water).
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| The extent of grain boundary carbide precipitation is controlled by alloy composition (in particular carbon and chromium), final mill annealing temperature, diffusivity of Material Characterization January 20 10 SG-CDME-09-4-NP Revision 0
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| 11-5 chromium, grain size, and the availability of dissolved carbon for precipitation at the grain boundaries.
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| Westinghouse, along with the industry in general, adopted a modified Huey test (ASTM A262 Practice C) as the principal tool for evaluation of grain boundary chromium depletion in Alloy 600. The test was modified to a single 48-hr exposure in boiling 25w%
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| nitric acid. This modification was necessary to enhance the sensitivity of the test for detecting chromium depletion.
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| Five modified Huey tests were performed: one from archived material and two from each of the pulled tubes. For each pulled tube a sample was chosen near the TTS and the other was chosen in a location remote from the TTS.
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| 11.5.2 Results The results of the 25w% HNO 3 Modified Huey tests are summarized in Table 11-3. The pulled tubes showed weight losses of 121-195 mg/dm2 /day. These results are less than that associated with a sensitized condition (200 mg/dm 2 /day) as stated in Westinghouse Procedure MR 9112, Revision 0, but only marginally. The pulled tubes are not sensitized.
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| In contrast, the archived tubing showed a weight loss of 27 mg/dm 2 /day. Investigation of this condition is continuing.
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| 11.6 Residual Stress 11.6.1 Introduction The hoop stress was measured by a split tube method per Westinghouse Procedure MCT-003, Revision 1. The procedure was used to measure the net-section residual hoop stress for the pulled tubes. The resulting calculated residual stress assumes a linear distribution of residual stress through the tube wall and is an approximate average value of the stresses over the whole specimen surface. When the tube is split, a change in strain is observed on the OD surface and is inversely related to the residual strain in the tubing.
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| Multiplying the observed strain by the elastic modulus (E) provides a value for the average residual stress.
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| 11.6.2 Procedure Three ring specimens were tested for residual hoop stress: R12C98 near the TTS, R12C98 remote from the TTS and section XA2 from the archived tube. The samples were chosen from areas that had not been exposed to forces above the yield strength of the material (either from the tube pull or burst tests). Thus the lower sample in R12C98 was taken from section 3 and no samples were obtained from tube R 11C62.
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| The residual stress was determined from change-in-diameter measurements. The OD of the tubing was measured prior to and following the cut. The tube section was slit axially along one side of the tube and the hoop stress was calculated from the diameter changes Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| 11-6 of the tube. The residual stresses were calculated from the average of the four readings for the wall thickness values and the measured diameters with the following equation:
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| G E ]W[ I 1I GR v D[o]~ Dri Where:
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| Gr = residual stress E = elastic modulus v = Poisson's Ratio W = average wall thickness Do = average OD before splitting Df = average OD after splitting 11.6.3 Results The experimental data are presented in Table 11-4. These values are within the range of residual stress levels expected for thermal treated Alloy 600 tubing produced by Westinghouse for Model F steam generators. Data obtained during the development of the thermal treatment process showed macro residual hoop stress levels from 0 to 3 ksi based on split ring methods.
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| 11.7 Surface Roughness Surface roughness measurements were made on the ID and OD surfaces of both pulled tubes and a sample from archived tubing from Heat 2272. Surface roughness measurements were made 'in the axial and circumferential directions.
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| Measurements were made with a Nanovea ST400 Optical Profilometer, a non-contact technique that uses reflected white light wavelength measurements to determine surface roughness. Each specimen was traversed under the instrument's light pen with a 3.5 mm measurement range, 75 nm vertical resolution and a 4 micron lateral resolution. The instrument was operated in accordance with the manufacturer's instructions. Software associated with the profiler was used to account for the curvature of the tube for measurements made in the circumferential direction.
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| Figure 11-14 through Figure 11-25 present the surface roughness profiles for each of the cases.
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| January 20100 Revision Characterization Material Characterization January 20 10 SG-CDME-09-4-NP Revision 0
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| 11-7 Table 11Il-1: Chemical Conmposition of Bulk Material
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| ~*K; ) T; SB 167-A02 outle-2v Eleent 12C9 Ri I1C62~ _N066O0tSpec ~Ntcs iN1 k ýRlI2C59 (2062 pulled tube)
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| Co 0.08 0.04 0.04 0.049 Cr 15.5 14.63 14.62 14.0-17.0 All in spec 14.535 Cu 0.29 0.03 0.03 0.5 max All in spec 0.209 Fe 9.49 9.67 9.67 6.0-10.0 All in spec 9.0286 Mg 0.02 0.01 0.01 0.015 Mn 0.21 0.09 0.09 1.0 max All in spec 0.168 Mo 0.21 <0.01 <0.01 0.179 Nb 0.17 0.02 0.02 0.125 Ni 73.27 74.86 74.88 72.0 min All in spec 72.622 Si 0.25 0.11 0.10 0.5 max All in spec 0.106 Ti 0.21 0.22 0.22 0.18 V 0.03 0.02 0.02 0.026 Pb 0.00045 0.00017 0.00017 0.023 C 0.021 0.033 0.033 0.15 max All in spec '0.032 S <0.001 0.001 0.001 0.015 max All in spec 0.001 N 0.0084 0.0081 0.0083 Table 11-2: Grain Size Summary Grain Siz7e U~SIng AST'M F1+ Grain Sizecsn J:ample.
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| Tube omiparison Method PaiPrrm*
| |
| RllC62 2A2B1 10 9.33 RllC62 3B3B 9 10.43 R12C98 2A2B2 10 10.55 R12C98 2A2B3 10 9.55 R12C98 5A5B 9 9.73 Archive XA4B 8. 8.66
| |
| (*) Presented for Information Only.
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| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-8 Table 11-3: Summary of Modified Huey.Results Vth Tub& Saniple IWei~ht loss.II,, dill-, &dI\
| |
| R11C62 2A3 120.9 R11C62 3B4 169.5 R12C98 2A2E 130.2 R12C98 5AiB 194.7 NX2272 XA3 27.1 Vogtle-2:
| |
| R12C59 4D 36.8 R12C59 4E 39.2 RllC60 4D 31.3 R11C60 4E 29.2 Seabrook:
| |
| R9C63CL 3E2 32.6 R9C63CL 6A3 35.1 R5C62HL 9A3 41.2 R5C62HL 3C2 86.8 Table 11-4: Summary of Residual Stress Measurements II A .. 1_'_ [ v A ('I flA'% I nina I I , n',r I Archive A Z U.U'4L- U.O!JU U.OyJ i.Z R12C98 3B2 0.040 0.688 0.688 1.276 R12C98 5A4 0.041 0.688 0.689 1.193 Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-9 R12C98 120000
| |
| [Ultimate Stress = 104452 1 100000 80000 60000 c-in Yield Stress = 49206 40000 20000 I *1 0
| |
| 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Strain (in/in)
| |
| Figure 11-1: Stress-Strain Curve for R12C98 Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-10 Heat 6722 120000 Ultimate Stress = 102080 1 100000 80000 60000
| |
| [Yield Stress = 46978 [
| |
| 40000 Mfg records for heat 6722:
| |
| Sy=46 ksi Su=102 ksi 20000 d 0
| |
| 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 Strain (in/in)
| |
| Figure 11-2: Stress-Strain Curve for Archived Tubing (Heat 2272)
| |
| Characterization Material Characterization January 20100 Revision Material January 2 010 SG-CDME-09-4-NP SG-CDME-09-4-NP Revision 0
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| | |
| I1-1 Figure 11-3: Microstructure of RI IC62 (Sample 2A2B1) After a Nital Etch Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-2 IA IB Figure 11-4: Carbide Distribution of RI 1C62 Near the TTS (Sample 2A2B 1)
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| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-3 ZA 2IJ Figure 1 1-4:Carbide Distribution of R 1C62 Near the TTS (Sample 2A2B1) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-4 IA lI I Figure 11-5: Carbide Distribution of R1IC62 Remote from TTS (Sample 3B3B)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-5 Figure 11-5:Carbide Distribution of R I 1C62 Remote from TTS (Sample 3B3B) (continued)
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| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-6 IA 10s Figure 11-6: Carbide Distribution of R12C98 Near from TTS (Sample 2A2B2)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-7 ZL-. z/J0 Figure 11-6:Carbide Distribution of R12C98 Near from TTS (Sample 2A2B2) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-8 WD no
| |
| - 78 mm mi~r-LUAUu o,;gnai Noise Reduclon S - :1: - Line Int. Done I *i,, I Date "29Jun W ]* IU Figure 11-7: Carbide Distribution of R12C98 Near from TTS (Sample 2A2B3)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-9 EN1T- iM W Signal A- SE2 i10Pmt Date.29Jen 20019 W thgmu WO - 7.7 mm Noise Redution - Line tnt. Dane EHT- 20.00 kV Signal A - SE2 10pm WD- 7.7 mm a eR ed. don- i . .D ane I I .29 Jun 2119 Date W tm Figure 1 -7:Carbide Distribution of R12C98 Near from TTS (Sample 2A2B3) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-10 EHT- 20lJD kV Signal A - SE2 lo PDan WO - 7.8 mm Noiae Reduclton - Line lnt.Done IDat IWW~gW :29 Jun 2M M Figure 11-7:Carbide Distribution of R12C98 Near from TTS (Sample 2A2B3) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 1l-1l E'T-WD20.00 7.8 mmkV SignalReduction Noise A- SE2 - Line lot. Done in PDate pin 29 Jun 2009 *Westin 1.
| |
| 7.8 mm
| |
| -- AAU tZIHT kV Noise SignalReduction A - SE2 - Line Inlt.Done I-p.maa2 u I Dote 29 Jn20 Jnn 2009 QPggW Figure 1 l-7:Carbide Distribution of R12C98 Near from TTS (Sample 2A2B3) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-12 IA 115 Figure 11-8: Carbide Distribution of R12C98 Remote from TTS (Sample 5A5B)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-13 2A 2B Figure 1 l-8:Carbide Distribution of R12C98 Remote from TTS (Sample 5A5B) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-14 WD= 2t.0k tEKT:- 4.7 mm Signal A - SEZ - Lin. Int. Done Noha. Reductlon _ _ _ _ _ Data24 Jan2009 1 qK*t*
| |
| Figure 11-9: Carbide Distribution of Heat 2272 Archive (Sample XA4B)
| |
| Material Characterization January 2010 SG-CDME-09-4-N P Revision 0
| |
| | |
| 11-15 EFlIT - 20.00 kV Signal A - SE2 1Upm I Dote 2*4Jun 2009 *WO*tIg0uuu
| |
| =" 4.7 mm Noise Reduction - Line Int. Done 4.7 mm tflE --euaJu iOV Noise lReduction 5I*l3niA z - Line Int. Done S Ste.Dte Jun 2 W 0st hw*mu Figure 1l-9:Carbide Distribution of Heat 2272 Archive (Sample XA413) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-16 EHT- 20A.W Signal A - S_ 2_0p. O WO - 9.1 ram Noise Reduction - Line Int. Done Date "24Jon 219 T"-2w k Signal A - SE2 t Date :24 Jun 2U09 OWeskif0Uae WD - 9.1 mm Nelse Reduction - Line Int. Done I -- 4 Figure 11-9:Carbide Distribution of Heat 2272 Archive (Sample XA4B) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-17 t LIII - IU.WU KIC 5Ig9nl A- NUC Daote24 Joe2M9 SW CStknghuu WD- 9.1 mm NoiseReduoion - Line Int. Don.
| |
| Figure 11-9:Carbide Distribution of Heat 2272 Archive (Sample XA4B) (continued)
| |
| Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 11-18 Figure 11-10: Microstructure of Vogtle-2 Tube Pulled in 2004 Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-19 Figure 11-11: Microstructure of Seabrook Tube Pulled in 2002 Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-20 350 330 310 P~ost Burst Test 290 Z 270 AAN 77NA / ,* x'x,[High Load During
| |
| * Seabrook (est) 250
| |
| - Heat 2272 6 R11C62 TTS+7"
| |
| .* 230 R1 1C62 TTS+0 210 190 1 '7A v v I/ I 150 -
| |
| 0 5 10 15 20 25 30 35 40 45 50 Distance from OD (inch)
| |
| Figure 11-12: Microhardness Traverses on Tube R 1IC62 Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-21 350 330 310 - V Post Burst Test 290
| |
| : 270
| |
| >_
| |
| * Seabrook (est)
| |
| Heat 2272
| |
| ~250 R12C98 TTS+71" 230'/ -- X R12C98 TTS-0.01" i
| |
| . 230 --e-R12C98 TTS+0 210 190 170 150 .
| |
| 0 5 10 15 20 25 30 35 40 45 50 Distance from OD (inch)
| |
| Figure 11-13: Microhardness Traverses on Tube R12C98 Material Characterization January 2010 SG-CDME-09-4-NP Rexvision ()
| |
| | |
| 11-22 Lerqthw107 mil PI w 03D9mil Scak a0.5 mil 01 432
| |
| -03 0 20 30 40 00 00 70 s Figure 11-14: RI IC62 (Sample 2A3) Axial ID Surface Roughness LengMt a103mii P1l.03 mit Scale2miI 1-o.a 0.4 0.2 0-
| |
| -0.2 0.04
| |
| -0.0 0 20 30 40 00 00 70 SAV Figure 11-15: R 11C62 (Sample 2A3) Circumferential ID Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-23 win Lerqh. 07 mil M pi.un Sile w 1000 pin 400 200
| |
| -400 0 10 20 30 40 50 e0 70 80 90 100 mw Figure 11-16: R 1IC62 (Sample 2A3) Axial OD Surface Roughness Win jLvte tho 103i M Pml 24 piin a 1000 *in 400 300 200 10.0 L RdIT1 I I U til I R
| |
| -100
| |
| -200 10 20 30 40 0000 70 so0g 10 Omnil Figure 11-17: R 11C62 (Sample 2A3) Circumferential GD Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-24 MIS L*ngth a 107 mil PI w 0 297 mil Scat& w 0. 5 mil 01 412
| |
| -023 0
| |
| 20 30 40 50 00 T0 s0 Figure 11-18: R12C98 (Sample 5A5A) Axial ID Surface Roughness L.np *M03 mil IF.
| |
| * 0,594 mil Soa
| |
| * I al mift 0.2 0.3 0.2 0-1 0-
| |
| &12
| |
| -01
| |
| &A 0 20 30 40 N to 70 so Figure 11-19: R12C98 (Sample 5A5A) Circumferential ID Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-25 Lwgth -109 mil Pt a0.233 mil SIok w0.4 mil 02-0 01 0 05
| |
| -o 05
| |
| .-o 00 30 40 50 eo 70 80 s0 100 Mil Figure 11-20: R12C98 (Sample 5A5A) Axial OD Surface Roughness m i 0.3 ni ScW w I* md IIrtJ -I 10 mi Pt 0
| |
| 0 14 0 13 0
| |
| 0 1~~J Atj &kf
| |
| -01 11 IMI I 4111111M 11111 V III YWT APT
| |
| .)'s 10 20 3040 00 00 70 so90 100Mg Figure 11-21: R12C98 (Sample 5A5A) Circumferential OD Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-26 rail L~ngth a170 ml Pt 28S mil Scak a 5 mil 3
| |
| I 0
| |
| -1 100 110 120 130 140 150 IeO 170 mil Figure 11-22: Archive Tubing (Heat 2272) Axial ID Surface Roughness mu ~ Le -tha 103rmil Pta 1.83 fmil Sl a= 3miI 05 0- A. AA -n&%L ]U- RL iL t/\1JIL(
| |
| L...w ý A i HN 0 10 20 30 40 50 80 70 80 90 100mini Figure 11-23: Archive Tubing (Heat 2272) Circumferential ID Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 11-27 IWVIA a 172 M41 Pt 00W ^Nil 50O4ua w..I 03 04 02~
| |
| -04 0 10 70 so so 100 110 120 110 140 Figure 11-24: Archive Tubing (Heat 2272) Axial OD Surface Roughness L*Math a 103 mnil Pt a 0.5W mil Seel*a I m~il 0.8 0.4 0.3 02 01 a-1
| |
| .0.2
| |
| -03
| |
| ,04 Figure 11-25: Archive Tubing (Heat 2272) Circumferential OD Surface Roughness Material Characterization January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-1 12.0 DISCUSSION / CONCLUSIONS
| |
| - The-non-destructive-and destructive examinations of hot:leg sections of-Vogtle- Isteam generator-tubes R 1IC62 andRl2C98 confirmed the presence of deep OD initiated intergranular stress corrosion cracking (ODSCC) within the expansion transition at the TTS. The corrosion was limited to the TTS region. RI IC62 had three throughwall axial cracks, each separated by about 550 of the circumference. R12C98 had cracking around the entire circumference of the tube; with a maximum depth of 80%TW and 21 % degraded area. There were other very short axial cracks identified on both tubes and both had small patches of IGA.
| |
| 12.1 Tube Integrity It was judged, based on the results of visual observations, dimensional measurements, laboratory eddy current signal increases and leak screening tests, that the cracks in tube R 1IC62, as received in the lab, were not representative of their in-generator condition. Given the changes to the cracks from the tube pull operations, post-pull measurements of SLB leak rates would not have yielded meaningful results.
| |
| Both pulled tubes were burst tested. Both tubes far exceeded burst test criteria of 3xNODP.
| |
| Table 12-1 presents a comparison of field sizing and the laboratory results. The sizing applied to the field results was generally poor, but this is likely due to the proximity of the TTS, the expansion transition and the short length of the cracks.
| |
| 12.2 Cause of Cracking Stress corrosion cracking, of any type, requires the simultaneous presence of three elements; if any one is absent, SCC will not initiate or will not propagate, if already initiated. These elements are:
| |
| : 1. A susceptible metallurgical condition. Depending on the environment, Alloy 600 in different metallurgical conditions (i.e., mill annealed, high temperature mill annealed, sensitized, cold worked) is susceptible to stress corrosion cracking.
| |
| : 2. A significant tensile stress (dependent on the environment to which the material is exposed).
| |
| : 3. An aggressive environment. Alloy 600, depending on its metallurgical condition, is susceptible to SCC in a wide range of environments, including high temperature pure or relatively pure water, caustic environments, acidic environments and relatively neutral environments contaminated with certain chemical species.
| |
| 12.2.1 Material Condition The Vogtle-l pulled tubes were not sensitized, but only marginally so. As Table 11-3 shows, the Vogtle- 1 pulled tubes had modified Huey weight losses that were higher than Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-2 archived material from Heat 2272. It was also higher than pulled A600TT tubes from Vogtle-2 and Seabrook.
| |
| The chemistry of the tube material was well within specifications. The two pulled tubes had nearly identical compositions, as was expected. The composition was close to that of the archived material. Both pulled tubes had a moderate carbon content (0.030 wt%).
| |
| The micrographs showed a fine grain microstructure (ASTM size 9-10).There was a relatively low density of grain boundary carbides for 600TT and a relatively high density of intragranular carbides. The low density of intergranular carbide precipitation suggests that the mill annealed treatment was ineffective in dissolving sufficient carbon and carbides. The fine grain size also suggests lower temperature mill anneal. Without sufficient carbon in solution, intergranular carbides cannot precipitate during the thermal treatment. Precipitation occurs on undissolved, intragranular carbides. There was no significant difference in the microstructure observed between regions near the cracks and remote from the cracks.
| |
| Tube manufacturing is considered in a later section.
| |
| 12.2.2 Stress The axial orientation of the cracks in R1IC62 indicates that the major stresses were in the hoop direction. The circumferential orientation of the cracks in R12C98 indicates that the major stresses were in the axial direction. Both of these stresses are present in the expansion transition and it is entirely likely that the expansion transition is the source of the stress that contributed to the cracking. The question that needs to be addressed is whether the stresses in these cracked tubes were unusual.
| |
| The residual stress measurements indicate that the tubes themselves did not have an elevated state of stress. The hoop stress of 1 ksi is to be expected for Westinghouse A600TT tubing, and is considerably smaller than the 12-22 ksi residual hoop stresses found in the pulled Seabrook tubes.
| |
| Figure 12-1 presents a comparison of the expansion transition dimensions of Vogtle- 1 pulled tube R12C98 and Vogtle-2 pulled tube R12C59. The figure shows that the profiles are nearly identical. The difference between the two tubes is that the Vogtle-2 tube did not have any cracking. This leads to the conclusion that there was nothing unusual about the Vogtle-1 expansion transitions.
| |
| IGA is a form of attack that occurs with or without a tensile stress. IGA can serve as an initiation site for IGSCC in the presence of a sufficient tensile stress. Shallow IGA was identified in the vicinity of the circumferential crack of R12C98 and on both sides of the 1600 crack of R 11C62. The lack of IGA around the 2100 and 270' axial cracks of R 1I C62 may be because the OD surface was heavily scraped in these areas and signs of IGA were removed. There was no indication that the IGA that was observed had any significant influence on the structure of the tube.
| |
| Discussion / Conclusions January 20 10 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-3 12.2.3 Chemistry Thecrevice-thatis formed between the -tube and the sludge pile attheTTS may serve as a site for the formation of an aggressive environment. These crevices are quite capable of being fouled with corrosion products from the feedtrain and once fouled, the crevices can become effective concentrators of contaminants such as chlorides, sulfates and similar aggressive species that are present in the feedwater as a result of condenser in-leakage.
| |
| When concentrated solutions form, the crevice becomes a preferential site for the initiation of tube corrosion.
| |
| The surface chemistry analysis did not yield any conclusive evidence about the nature of the environment at the TTS. Copper was identified on the OD surface but not within the cracks. Copper can be associated with an oxidizing environment; however the oxidation state of the copper could not be assessed from EDS testing. Lead was identified on the OD surface, but there is reason to believe that it was introduced by handling. Lead has been associated with both IGSCC and transgranular SCC of Alloy 600 in secondary-side environments, although the level of lead required to initiate corrosion is undecided. The effect of the lead in the crevice environment could not be assessed from EDS testing, however its presence was confirmed.
| |
| Steam generator operations are considered in another section.
| |
| 12.3 A600TT Field Performance The Vogtle-l steam generator tubes are A600TT. A600TT is more resistant to stress corrosion cracking than the mill annealed condition, but is not immune. A600TT is a common material used in steam generator tubing. Table 12-2 is a listing of plants world-wide that are equipped with A600TT tubes. The Framatome-manufactured SGs have hard roll expansion in the tubesheet.
| |
| Field experience with Alloy 600TT tubes has generally been excellent, especially in domestic replacement SGs. Suspected corrosion related degradation in domestic replacement steam generators has occurred at Surry 1 and Turkey Point 4 where tubes have been plugged because of cold leg pit indications, and at Turkey Point 3 and Turkey Point 4 where tubes have been plugged for potential volumetric indications near the top of tubesheet (many of which have been subsequently determined to be geometric artifacts and not tube degradation). The first evidence of cracking in these SGs is an ID indication at the hot leg tube end of Surry Unit 2 in the fall of 2006. None of these degradation mechanisms in domestic replacement steam generators have been confirmed by laboratory destructive examination of pulled tubes; pitting was confirmed by UT examination at Surry 2.
| |
| Field experience with Alloy 600TT tubes in original domestic SGs has also been quite good.
| |
| Nine additional U.S. plants commenced operation with Alloy 600TT tubes. These plants have approximately 189,900 tubes installed, operate at hot leg temperatures of 599 to 620'F and have operated for as much as 20 EFPY. The number of tubes plugged due to suspected corrosion in these plants (and one related plant) is given in Table 12-3.
| |
| Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-4 There are also about 40 non-US plants with Alloy 600TT tubes. These plants have over 614,000 tubes installed, operate with hot leg temperatures of 610 to 621'F and have over 13 EFPY of operatingexperience- The -experience with Alloy 600TT tubes in-these plants has not been as good as in the U.S., although performance has been significantly better than that of the mill annealed condition. In France, over 280 tubes have been plugged because of ID initiated stress corrosion cracking (PWSCC) at the top of the tubesheet. More recently, over 2500 Alloy 600TT tubes have been plugged or sleeved because of PWSCC at the TTS and at tube support locations in 3 Korean plants. KoRi 2 encountered top of tubesheet denting and plugged over 125 tubes in 1986; ODSCC was confirmed by tube pull. Unconfirmed reports of ODSCC in other Model F units in Korea have been identified.
| |
| Domestically, tubes have been pulled from three plants with A600TT: Seabrook, Plant A and Vogtle-2. These are summarized below.
| |
| 12.3.1 Seabrook Pulled Tubes From Reference 4:
| |
| In May 2002, during the OR08 outage, 15 tubes at 42 TSP intersections were reported with crack-like indications. Some of the intersections were reported to contain multiple indications. Originally reported as distorted support plate indications (DSI) from the 100% bobbin inspection program, these indications were confirmed as crack-like with the
| |
| +PointTM rotating probe according to the inspection plan. Further independent confirmation was provided that these indications were crack-like by application of the Ultrasonic Test Eddy Current (UTEC) system.
| |
| The indications were reported at the intersections with the first support plate above the FDB (02H in the eddy current inspection database) through the fifth TSP above the FDB (06H) on the hot leg of SG-D, and between 03C and 05C on the cold leg of SG-D. No indications were reported in SGs A, B and C, which were also 100% inspected during May 2002.
| |
| A lookback evaluation of the data from the previous inspection showed the presence of a non-callable signal at 25 of the 42 locations. The remaining 17 intersections exhibited no signal during the previous inspection.
| |
| There were a number of unusual aspects to these indications:
| |
| : 1. Seabrook has significantly less operating time than many of the other Model F SG plants that have not observed tube cracking; thus, these indications were unanticipated.
| |
| : 2. Indications were detected in only SG-D.
| |
| : 3. Indications were found at the TSP intersections and not at the top of the tubesheet (TTS) expansion transition where initial cracking would be expected.
| |
| : 4. Indications were reported on both the HL and CL. In all cases where a CL indication was reported, a HL indication was also reported on the same tube. CL cracking at the same time as HL cracking is unexpected due to the lower temperature on the CL.
| |
| Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-5
| |
| : 5. All indications were confined to rows 4 through 9.
| |
| : 6. Multiple TSP intersections on the same tube were reported in most cases. The
| |
| - indications-on only'3'of the 15 tubes reported were confined to a single TSP intersection.
| |
| Two tubes were removed (pulled) from SG-D in May 2002. Selection of the tubes for removal was based on recovering the largest indication, obtaining as large a population of degraded and un-degraded intersections as possible, and obtaining both HL and CL indications. The tube pull plan included removing 3 tubes, R4C63-HL, R5C62-HL and R9C63-CL; this plan was later adjusted to 2 tubes when tooling issues were encountered during the pulling of R4C63.
| |
| Axial OD-initiated intergranular stress corrosion cracking was confirmed at the tube-TSP locations on both R5C62-HL and R9C63-CL. The microstructure and mechanical properties of the tubes indicated a fine-grain material with elevated tensile strength, with a low density of carbides at'the grain boundaries. While it was concluded that these pulled Seabrook tubes had received a thermal treatment, these features suggest a material with less-than-optimum resistance to stress corrosion cracking. The magnitude of the residual hoop stresses measured for sections of these tubes was in the range from 11.7 to 21.6 ksi. This is much higher than normal for thermally treated Alloy 600.
| |
| The results of the microchemistry analyses of surface deposits and crack faces did not identify the presence of any contaminating species in sufficient concentrations to explain the cracking.
| |
| The Seabrook experience suggests that under some circumstances Alloy 600TT tubing in quatrefoil TSP configurations is susceptible to ODSCC. Guidance on this phenomenon is available in Reference 3.
| |
| 12.3.2 Plant A Pulled Tubes From Reference 5:
| |
| During the Plant A's 1998 Spring outage (after 8.6 EFPY), three tubes were removed from the hot leg of steam generator B, R27C32 (4 sections), R34C96 (3 sections) and R40C88 (3 sections), because they had OD initiated, circumferentially oriented, +PointTM eddy current test (ECT) indications at the TTS. These indications ranged from 0.19-0.32 volt prior to removal from the generator. After removal from the generator, the tubes were re-tested on the platform; only R40C88 had a detectable indication (0.59 volt).
| |
| The destructive examination of Plant A tubes R27C32, R34C96 and R40C88 demonstrated that the ECT and UT indications at the TTS of each tube were due to shallow, narrow circumferential regions of mechanical damage on the OD surface which were covered by a narrow, but thick, circumferential band of adherent deposits.
| |
| Corrosion was not observed on any tube surface provided. The ID surfaces examined appeared to be free of manufacturing or service induced corrosion or mechanical damage as well. Also, the examinations did not identify any areas of significant wear, fatigue or Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-6 other types of mechanical degradation in the one tube support intersection provided (tube R27C32 TSP 03H).
| |
| 12.3.3 Vogtle-2 Pulled Tubes From Reference 6:
| |
| During the Vogtle Unit 2 2R10 refueling outage, circumferential oriented flaw-like indications were reported at the top of tubesheet. Based on +PointTM inspection data, the indications were reported to be within or at the hydraulic expansion transition at the TTS on the hot leg of the SG in all cases. A total of nine tubes in the four Vogtle-2 SGs were reported with flaw-like +PointTM signals. Ultrasonic testing (UTEC) performed on 8 tubes in SG2 and SG3 corroborated 4 of the 6 +PointTM circumferential indications (SCI) and, resolved as NDD, 2 tubes with PVN indications that masked the TSH region. The 2RI0 outage was conducted after cumulative service equivalent to -13.4 EFPY. Due to the unexpected identification of flaw-like indications in the Vogtle Unit 2 steam generators, two tubes were removed from SG2 for detailed laboratory examination. The tubes were located at R12C59 HL and R 11C60 HL and were cut below the 2nd tube support plate (211).
| |
| The results of the laboratory analyses of Vogtle-2 pulled tubes showed that the flaw like signals reported at the top of the tubesheet did not represent circumferential ODSCC in the hydraulic transitions. It was not possible to determine the root cause of the field flaw-like signals, but it is thought that it was due to the nature and the non-homogeneity of scale/deposits on the tubes at the top of the HL tubesheet.
| |
| 12.4 Steam Generator Operation Vogtle Unit 1 has operated with SG primary coolant inlet temperature (T-hot) of 6187F prior to 1R14. However, T-hot was raised to 6207F during Cycle 15 (Reference 1).
| |
| The operating interval defined by Cycle 11 was punctuated by a chemical contamination event that occurred. in November 2002, affecting the SG chemical environment in both Vogtle Units 1 and 2. Reference 7 provided a brief synopsis of the event: Summarized briefly, ingress of sodium hexametaphosphate into secondary cycle of both units occurred as a result of addition of the wrong chemical to chemical feed tanks. Upon identification of the abnormal chemistry condition, chemical feed was isolated within 45 minutes of initiation of excursion at Unit 1 and 90 minutes at Unit 2. Unit 2 entered Mode 3 within 3.5 hours; Unit 1 entered Mode 3 within 6.5 hours. Cleanup was conducted by maximizing blowdown for several hours as the plant was brought to Cold Shutdown conditions, followed by repetitive drain and fill cycles until target sodium and phosphate levels were achieved. Since there were no existing phosphate specifications in the chemistry guidelines, control was based on those specified for sulfates.
| |
| Hideout return and programmed holds at 4007F and Hot Shutdown were employed to track the contaminant levels during the recovery period. Inventory balances calculated from the chemistry monitoring suggests that roughly complete elimination of the injected inventory was achieved.
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| Most residual contaminant remaining in the steam generator was phosphate that had absorbed into or reacted with magnetite deposits within the steam generator tube bundle. In order to Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-7 remove additional contaminant and to assess the inventory of contaminants remaining in the steam generators, a mid-cycle flush was performed in the time period May 8 to 15, 2003. Initial results indicate that 8.4- grams phosphate and 3.2 grams sodium were removed during the flush period.
| |
| The tube integrity concern associated with the November 2002 contaminant transient is that caustic species may have been introduced to crevice environments such as the expansion at the top of the tubesheet, the sludge pile and freespan deposits, and quatrefoil land interfaces in the support plates. The rapid actions taken by the plant to limit exposure of the tubes to potentially deleterious conditions are likely to have been effective. Long term concern for the effects of residual phosphate, such as tube material dissolution and possible crack initiation in an acidic solution are potentially relevant to a root cause evaluation. The 100% full length bobbin inspection and 50% TTS +PointTM examination of SG2 and SG3 during 1R 1I confirmed the absence of outer diameter stress corrosion cracking (ODSCC) from SGs 2 and 3.
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| No atypical chemistry operations were reported for steam generator and other secondary system chemistry parameters at any times during the last four fuel cycles. No significant chemistry deviations were reported during Cycle 12, Cycle 13, Cycle 14 or Cycle 15 (Reference 7, Reference 8, Reference 9 and Reference 1, respectively).
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| Vogtle Unit 1 was chemically cleaned during the 1R13 outage (Reference 10).
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| 12.5 Tube Processing Overview The Vogtle-l steam generators were manufactured in Westinghouse's Tampa facilities and shipped to the Vogtle site in September 1981. The Millstone-3 and Kori-4 Model F steam generators are of a similar vintage and were shipped prior to and immediately after the Vogtle- 1 steam generators, respectively (Reference 2).
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| A manufacturing/delivery timeline of Model F steam generator tubing sets that were installed into their respective steam generators prior to delivery, is shown in Figure 12-2 (Reference 4). A set of tubes is generally the complement of tubes for a single SG, plus spares. However, it is not unusual to find that the tube complement for some SGs is comprised of tubes from several different sets. It is presumed that this is the result of manufacturing sequence and manufacturing efficiency. This timeline shows that the Vogtle-1 steam generator tubes were manufactured (delivered) between June and September 1980. Some of the tubing sets manufactured at about the same time as the Vogtle-1 tubing sets were installed in the Vogtle-2, Salem-l, Millstone-3, Kori 3 and Kori 4 steam generators.
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| Figure 12-3 shows the process flow for manufacturing the Alloy 600TT tubing utilized in the Vogtle-1 SGs. The starting point of the process was the receipt of a "Lot" of TREXes (tube reduced extrusions). TREXes were ordered by weight to produce the desired length of tubes. For the later tube production- this is interpreted to include the Vogtle-1 tubes, 90% of the TREXes in a Lot was required to be from the same heat of material. The mill practice was to process a Lot of TREXes at the same time; this is logical because the tubes produced from a single Lot of TREXes would, by plan, all be approximately the same length.
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| Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-8 Following a cold pilgering and two cold drawing processes, separated by intermediate mill annealing for 5 minutes at 1900'F, the tubes were final mill annealed in a continuous belt,
| |
| -hydrogen environment furnace. Twentyztwo tubes (11/16" dia.) were placed across the width of-the belt, which traveled at 3.25 ft/min. Care was taken to maintain both the material heat number and the TREX Lot number that were vibro-etched into the tube at one end.
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| Following mechanical straightening, belt polishing, and re-marking, the tubes were binned by length, approximately 20 different lengths for the rows 1-59 U-bends. (The difference in length between a row 1 tube and a row 59 tube is greater than 15 feet.) When sufficient tubes were available in the bins, the tubes were loaded into the thermal treating furnace segregated by length in 5 different compartments on the loading rack (see Figure 12-6), longer tubes on the bottom, shorter ones on the top.
| |
| The thermal treating furnace was a vacuum furnace, electrically heated by 9 banks of heaters that were independently controlled in three regions along the length of the furnace. Figure 12-4 shows one of the two furnaces utilized during tubing production; Figure 12-5 shows the heater control panel for the furnace. Figure 12-6 shows the loading rack for the tubes and the identification of the loading compartments.
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| Records were maintained for each furnace load (number assigned that identified the furnace used, A or B, and the rack location of tube (A through E) and the heat number for each tube).
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| The furnace load number was assigned prior to unloading the furnace. If a tube had been previously thermally treated, the records also indicated the prior thermal treatment furnace load number. Re-thermal treatment was required if straightening was performed after the initial thermal treatment. A straightening procedure was always followed by belt polishing that would remove the original vibrotooled identification. Since it was required to vibro-etch the thermal treatment batch number on each tube prior to unloading it from the furnace, each re-worked tube would display the final thermal treatment batch number. Re-thermal treatment was not uncommon; however re-straightening was not frequently performed.
| |
| The thermal treatment specification limited the total time of exposure to the 1320'F environment to 30 hours; thus, it was possible to perform two thermal treatments and one stress relief of the rows 1-10 U-bends within the required time limit. If straightening was performed after the second thermal treatment, the tube could not be re-thermally treated.
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| After thermal treatment, the tubes were bent into U-bends. A tube was not bent unless it was verified and recorded that a thermal treatment lot number was evident on the tube. Following bending, the rows 1 through 10 U-bends were stress-relieved in the area of the bends. The U-bends were loaded into the vacuum furnace (the same furnace used for thermal treatment) as shown on the schematic in Figure 12-7. The U-bends were nested, and stacked about 22 tubes high, held in a modified rack that prevented relaxation of the U-bends. Only the central region of the furnace was heated, so that the heated zone on the U-bends extended from about the elevation of TSP6 hot leg to cold leg. The tubes were maintained at 1320'F for 2 hours.
| |
| A review of specific Vogtle- I manufacturing records could not be completed, as the records could not be located. However, a review of the records would have unlikely revealed any Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-9 conditions out of specification for the installed tubes. If something did happen during the processing, the tube would have been rejected, and therefore not installed. The records were generally not-detailed enough, to assign actual point specific heat treatmentfurnace location; and other processing characteristics to a specific tube from a SG. The tubes were treated per the process specification and what the accepted, range of that specification detailed within the QA procedure.
| |
| Some of the manufacturing records were available prior to 2007. A study had been conducted to correlate heat numbers with specific tubes (Reference 15). The tubes that had experienced ODSCC in Vogtle-1 (Table 1-2) were compared with the tubing logs of Reference 15 to determine if corrosion was specific to a particular heat of material. Table 12-4 summarizes the results of this investigation. While Heat 2272 stands out as having the tubes with the most ODSCC (16 of 49 tubes), it is also the second most common heat of material at Vogtle-l. There is no correlation with heat number and ODSCC.
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| 12.6 Conclusions o The Vogtle- 1 indications are ODSCC cracks contained within the expansion transition.
| |
| * The cracks did not violate burst pressure criteria.
| |
| * The microstructure indicates that the material did not respond as anticipated to thermal treatment, resulting in non-optimal microstructure.
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| * The Vogtle-1 ODSCC is dissimilar to Seabrook ODSCC.
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| Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-10 Table 12-1: Comparison of Field Sizing and Lab Results iij?<Field<< ~< 7 Lab Field La Call SOI SCI SAI MAI Max. Depth 54%TW 80%TW 77%TW 100%TW PDA 7.3 21 _
| |
| Extent 51 ° 3600 0.18 inch 0.142 inch Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-11 Table 12-2: Operating Plant SGs Equipped with Alloy 600TT Tubes
| |
| .. Tfubes, 7 ,e~ar SPlant Model SGs /SG:.,S G]In stalled - Plawt o, SGs -"St; Installed ILS WP~tinQhnh1~ R~n12ePmPnt SGS France Framatome OEM SGs Indian Point 2 44F 4 3214 2000 Belleville 1 68/19 4 5342 1987 Point Beach 1 44F 2 3214 1984 Belleville 2 68/19 4 5342 1988 Robinson 2 44F 3 3214 1985 Cattenom 1 68/19 4 5342 1986 Salem 1 F 4 5626 1998 Cattenom2 68/19 4 5342 1987 Surry I 51F 3 3342 1981 Cattenom 3 68/19 4 5342 1990 Sury52 51F 3 3342 1980 Cattenom 4 68/19 4 5342 1991 Turkey Point 3 44F 3 3214 1982 Chinon B3 51B 3 3330 1986 Turkey Point 4 44F 3 3214 1983 Chinon B4 51B 3 3330 1987 Cruas 1 51B 3 3330 1983 Cruas 2 51B 3 3330 1983 Cruas 3 51B 3 3330 1984 Cruas 4 51B 3 3330 1984 U.S. Westinghouse OEM SGs Flamanville 1 68/19 4 5342 1985 Braidwood 2 D5 4 4530 1988 Flamanville 2 68/19 4 5342 1986 Byron 2 D5 4 4530 1987 Golfech 1 68/19 4 5342 1990 Catawba 2 D5 4 4530 1986 Golfech 2 68/19 4 5342 1993 Comanche Peak 2 D5 4 4530 1993 Gravelines C5 51B 3 3330 1984 Millstone 3 F 4 5626 1986 GravelinesC6 51B 3 3330 1985 Seabrook 1 F 4 5626 1989 Nogent 1 68/19 4 5342 1987 Vogtle 1 F 4 5626 1987 Nogent 2 68/19 4 5342 1988 Vogtle 2 F 4 5626 1989 Paluel 1 68/19 4 5342 1984 Wolf Creek 1 F 4 5626 1985 Paluel 2 68/19 4 5342 1984 Callaway* (RI-10) F 4 5626 1984 Paluel 3 68/19 4 5342 1985 Overseas Westinghouse OEM SGs Paluel 4 68/19 4 5342 1986 KoRi 2 F 2 5626 1983 Penly 1 68/19 4 5342 1990 KoRi 3 F 3 5626 1985 St. Alban 1 68/19 4 5342 1985 KoRi 4 F 3 5626 1986 St. Alban 2 68/19 4 5342 1986 Maanshan 1 F 3 5626 1984 Japan MHI OEM SGs Maanshan 2 F 3 5626 1985 Sendai 1 51M 3 3382 1983 Vandellos 2 F 3 5626 1987 Sendai 2 51F 3 3382 1985 Yonggwang I F 3 5626 1986 Takahama 3 51F 3 3382 1984 Yonggwang2 F 3 5626 1986 Takahama 4 51F 3 3382 1984 Tomari 1 51F 2 3382 1988 Tomari 2 51F 2 3382 1990
| |
| _Tsuruga2 51FA 4 3382 1986
| |
| * Callaway SG Replacement completed Fall 2005; RSG = Framatome 73/19 with 1-690 tubes Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-12 Table 12-3: Original SGs with.Alloy 600TT Tubing- Estimated Total Number of Tubes Plugged Due to Suspected Corrosion
| |
| ~Plant 1So'~ ]Approx JModel j FPY, J7
| |
| - su 6td.Tb CoiQi Degradatigif I tube with suspected PWSCC at U-bend at 5.8 EFPY. 3 tubes Braidwood 2 D5 18 with OD indications at supports similar to Seabrook. 16 tubes with indications at tube end Byron 2 D5 18 None 1 tube with circ. ID indication in tubesheet, tube end crack
| |
| .indications in many tubes, 8 tubes OD axial indications at TTS Comanche D5 14 9 axial and 4 circ PWSCC indications at tube ends (Ref. 102)
| |
| Peak 2 Millstone 3 F 16 None Salem 1_) F 9 (RSGs) None 18 tubes with OD indications at tube supports. First detected at Seabrook F 14.8 9.7 EFPY. 3 additional tubes plugged preventively. One tube with axial ODSCC at TTS found at 2009 outage.
| |
| 2 tubes with circ. ID indications in tubesheet at 14.6 EFPY, 17 OD circ. indications and 1 D axial indication at TTS at 17.1 EFPY, 10 tubes with circ. ODSCC and 1 axial OD indications at 18.4 EFPY. 20 tubes with circ. GDSCC at 19.8 EFPY 9 tubes suspected with circ ODSCC at TTS, later determined to be geometric. by pulled tube lab exam.
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| Wolf Creek F 20.2 9 tubes with ID indications at tube end Note 1:Built as original SGs for Seabrook 2, installed as replacements at Salem 1 Discussion / Conclusions January 2010 SG-CDME-09-4-N P Revision 0
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| | |
| 12-13 Table 12-4: Heats with ODSCC at Vogtle-1 Tubes with ODSCC All Tubes at Vogtle- 1 Percent with Heat SG1 SG2 SG3 SG4 Total SG1 SG2 SG3 SG4 Total ODSCC 1048 1 1 1 1 0 0 2 50.00 1828 3 3 13 7 0 0 20 15.00 1718 1 1 5 1 1 1 8 12.50 1458 1 1 9 7 0 5 21 4.76 1812 1 13 3 4 4 24 4.17 2061 2 2 29 10 19 11 69 2.90 2272 1 4 11 16 5 145 339 256 745 2.15 2079 1 1 46 8 7 0 61 1.64 2058 1 1 46 9 7 4 66 1.52 1879 1 1 68 15 5 4 92 1.09 2118 1 1 2 45 32 94 25 196 1.02 1994 1 1 2 144 70 12 4 230 0.87 2192 1 1 0 3 62 52 117 0.85 2212 1 2 3 3 83 164 127 377 0.80 2120 1 1 67 52 16 11 146 0.68 2211 1 1 2 2 88 102 195 387 0.52 2048 1 1 2 277 132 73 24 506 0.40 2109 1 1 2 192 138 176 69 575 0.35 2273 1 1 5 132 123 35 295 0.34 2001 1 1 229 64 45 10 348 0.29 2154 1 1 32 166 126 56 380 0.26 2152 1 1 100 105 134 55 394 0.25 2137 1 1 175 175 58 22 430 0.23 2277 1 1 0 134 249 242 625 0.16 Total 18 5 9 17 49 5626 5626 5577 5302 22131 0.22 Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-14 a,c,e; Figure 12-1: Comparison of Vogtle-1 and Vogtle-2 Expansion Transitions Discussion / Conclusions January2010 SG-CDME-09-4-NP Revision 0
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| | |
| 12-15 Plant J-77 J-77 A-77 S-77 0-77 N 77 D-77J-"78 F-78 M_-78 A"8 M"8 J"8 J-7 A7881 S-78 0-78 N-78D-8 Callaway _______ 202 ___ 206 208 ___ ___ ___ ___ ___ - ___ 71___ 07
| |
| " II 2321 237, Wolf Creek 234 . 239 Sea 2777--., roo -278
| |
| -,-.' Z J-79 F-79 M-79 A-791 M-79 J-79 I J-79 A-79 S-791 0-79 N-79 D-79 J-_80 F-80 M -80' N-iot'-' S -82
| |
| - -~~~~~ 253, __ __
| |
| Vandellos 2 247 255 320 Kori 2 249 251 257 Vogtle 1 257 2612T Napot P4oint 263 265 21 277, 289,92, '25"9, 269 ,
| |
| Seabrook 126 273 279 275,285 Millstoneanha 237 7 281, 285, 28
| |
| * -w-* 3---- - *o8........- --- 1289, 288 290 lKori Sae 3Seabrook 1 2) 287727 27902831 32: _4 A-ongw M -8 J-8 J8 291,A -8 S-8 F8 M-81 A-8
| |
| . M..-815 3-16 t-8 A- 31 ' -* ......
| |
| ng2 289, 292, Vogtle 1 1290 293 294 Koi4 290 297 301 303 304 305, Vogtle 2 290 __ 301 306 307 295, 296, Salem 1 (Seabrook 2) 2901 1 298 3011 302
| |
| _ __ _ _ _ _ _ _ _ S -1811 0_ 811 N-81 1 J-82T F-821 M -82A- 82 M -2 J-821 J-821 A-82 S-82 0-821 Y eonggw ang 1 38 1 30 1 1 3 0 Figure 12-2: Tubing Manufaturing Timeline Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-16 Receive a "Lot" of A TREX is 2.25" dia. x 0.25" wall of length sufficient to make about 3 tubes of a given length. TREXES were purchased by weight to make TREXes from ] specific lengths of tubes in about 20 gradations. A "lot" of TREXes was Huntington Alloys. required to be about 90-% from the same heat of material. TheTREX.lot number was tracked through the manufacturing process Clean and Pickle tl Cold Pilger Cold Pilgering reduced the TREX to 1.150" dia. x 0.078" wall; Lot and heat number transferred to finished piece prior to anneal I
| |
| n aIntermediate Point and Lube Anneal 1900 F for -5 minutes, for workability of the material Reduce to 1.00" dia x 0.055" wall; lot and heat number transferred to Cold Draw finished piece prior to anneal Clean Straighten Intermediate 1900 F for -5 minutes, for workability of the material Anneal Reduce to 0.692" dia x 0.042" wall;cut to length; lot and heat number transferred to finished piece and furnace load number assigned prior to anneal 1950 F for 2-3 minutes; Recrystallization step; continuous belt process; 22 Final Anneal tubes side by side on a moving belt.
| |
| Straighten As required; 7-roll straightener Belt polish full length; allowance in as-drawn tube diameter for material removal of about 0.003" Eddy current and Ultrasonic Test Only if tubes were re-straightened; otherwise skip. 1320 F for 10 hours; Restraightening permitted, but re-thermal treatment is required, subject to the 30 hour limitation on on time at temperature.
| |
| Assign new thermal treat batch number.
| |
| 1320 F for 10 hours; Maximum furnace load was about 625 tubes; tubes from individual length bins were segregated in the 5 furnace load cart positions; assign thermal treat batch number Appearance, straightness, etc.;
| |
| Verify presence of thermal treat batch number before bending; If number Bend U-bends absent, reject the tube.
| |
| Rows 1 through 10 only; 1320 F for 2 hours; Tubes loaded into furnace bend apex to bend apex in the middle of the furnace; U-bends were nested and stacked about 22 tubes high BoxAssign Set Transfer Heat number to tag attched to U-bend; cut off long ends and archive a Number and Ship sample of the cut off tubes Figure 12-3: Tube Manufacturing Sequence Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-17 Figure 12-4: Thermal Treatment Facility: (a) Vacuum Furnace Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-18 Independent heater
| |
| -controls - 9; three furnace zones Figure 12-5: Thermal Treatment Facility: (b) Furnace Controls Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-19 LE C D Loading Rack with Removable Separators Total capacity of the rack was about 625; 125 tubes per section (A,B,C,D), and about 125 tubes on top of the rack (E).
| |
| Figure 12-6: Thermal Treatment Furnace Loading Rack Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 12-20 Zonel1 Zone 2 bne 3 Zone 4 Zone5 Zbne 6 Zone 7 Zone8 Zone9 Zones 1 through 9 are heating zones in the furnace. Only zones 4, 5 and 6 were activated for stress relief of the u-bends.
| |
| Figure 12-7: Schematic of Furnace Loading for U-Bend Stress Relief Discussion / Conclusions January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 13-1
| |
| | |
| ==13.0 REFERENCES==
| |
| | |
| -. "Steam-Generator Degradation Assessment-for-Vogtle Unit 1 September 2009 Outage:
| |
| (1R15)," SG-SGMP-09-2, September 2009.
| |
| : 2. "Steam Generator Information Report," NSD-RMW-90-070 and SG-90-02-026, Revision 6, February 1990.
| |
| : 3. SGMP Information Letter on an Example Methodology for Screening of Alloy 600TT Tubing for the Seabrook Elevated Residual Stress Issue, 9/14/2004.
| |
| : 4. "Part 1 of 2, FPL Energy, Seabrook Station, Root Cause Analysis for CR 02-08166 Evaluation of 'D' Steam Generator Tube Cracking," USNRC ADAMS Accession No. ML023240493, November 5, 2002 and "Part 2 of 2, FPL Energy, Seabrook Station, Root Cause Analysis for CR 02-08166 Evaluation of 'D' Steam Generator Tube Cracking,"
| |
| USNRC ADAMS Accession No. ML023240512, November 8, 2002.
| |
| : 5. ABB Combustion Engineering Report 159-PENG-TR-134, January 1999.
| |
| : 6. "Vogtle Electric Generating Plant - 2R10 Steam Generator Tube Pull Test Results,"
| |
| USNRC ADAMS Accession No. ML050060198, December 21, 2004.
| |
| : 7. "SG Degradation Assessment for Vogtle Unit 1, 1R12 Refueling Outage," SG-SGDA 4, March 2005.
| |
| : 8. "SG Degradation Assessment for Vogtle Unit 1, 1R13 Refueling Outage," SG-SGDA 26, September 2006.
| |
| : 9. "Steam Generator Degradation Assessment for Vogtle Unit 1 March-April 2008 Outage (1R14)," SG-CDME-08-2, March 2008.
| |
| : 10. "Vogtle Electric Generating Plant Units 1 And 2: Steam Generator Chemical Cleaning Final Process Description", Westinghouse Letter GP- 17801, August 31, 2005.
| |
| : 11. WCAP 15573, Revision 1, "Depth-Based SG Tube Repair Criteria for Axial PWSCC at Dented TSP Intersections - Alternate Burst Pressure Correlation", October 2001.
| |
| : 12. "Vogtle Unit 1R14 Refueling Outage Condition Monitoring and Operational Assessments," SG-CDME-08-27,, July 2008.
| |
| : 13. "Westinghouse Level II Policies and Procedures Rev. 0," Westinghouse Quality Management System, Effective 8/3/09.
| |
| : 14. Southern Nuclear Operating Company Purchase Order 7086722, "Tube Pull Analysis,"
| |
| February 18, 2009.
| |
| : 15. "Vogtle 1 Tubing Logs," LTR-CDME-07-73, April 4, 2007.
| |
| : 16. "Pulled Tubes Receipt," LTR-CDME-09-41, March 18, 2009.
| |
| : 17. "Steam Generator Tube Sample Identification," Westinghouse Science and Technology Department Procedure MR 0201, Rev 0, June 18, 2002.
| |
| : 18. W. R. Junker and B. J. Taszarek, "Liquid Metal Modeling of the Eddy Current Response," Materials Evaluation, Volume 46, No. 12, pages 1564-1569, 1988.
| |
| : 19. "Steam Generator Program Guidelines," NEI 97-06, Revision 2, May 2005.
| |
| References January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| 13-2
| |
| : 20. SG-CDME-08-2, "Steam Generator Degradation Assessment for Vogtle Unit 1 March-April 2008 Outage (1R14)," March 2008.
| |
| : 21. EPRI Report 1014983, 'Steam Generator In Situ Pressure Test Guidelines," Revision 3, 2007.
| |
| : 22. "Steam Generator Tube Integrity, Volume 1: Burst Test Validation of Rupture Criteria (Framatome Data)," EPRI EP-NP-6865-L, Volume 1, June 1991.
| |
| : 23. "Vogtle-1 Pulled Steam Generator Tubes - April 6 Telecon," E-Mail from T. Magee to S.
| |
| LeBlanc et. al., April 16, 2009.
| |
| : 24. "Examination of a Steam Generator Tube Removed from Sequoyah Unit 2," SG-CDME-07-2 1-NP, September 2007.
| |
| : 25. "Burst Testing of Steam Generator Tubing," NSMT 9119, Rev. 4, March 31, 2009.
| |
| : 26. "Steam Generator Tubing Burst Testing and Leak Rate Testing Guidelines," EPRI Report 1006783, Electric Power Research Institute, Palo Alto, CA, December 2002.
| |
| : 27. "Steam Generator Degradation Specific Management Flaw Handbook," Revision 0, EPRI Report 1001191, January 2001.
| |
| : 28. Dirats Laboratories, Report Number R504184, August 26, 2009.
| |
| References January 2010 SG-CDME-09-4-NP Revision 0
| |
| | |
| Supplement to 1 R1 4 Steam Generator Inspection Report -
| |
| Tube Pull Examination Results Enclosure 3 Westinghouse Electric Company LLC, LTR-CAW-10-2731, "Application for Withholding Proprietary Information from Public Disclosure"
| |
| | |
| )Wesinghouse Westinghouse Electric Company Nuclear Services P.O. Box 355 Pittsburgh, Pennsylvania 15230-0355 USA U.S. Nuclear Regulatory Commission Direct tel: (412) 374-4643 Document Control Desk Direct fax: (412) 374-3846 Washington, DC 20555-0001 e-mail: greshaja@westinghouse.com CAW 2731 January 14, 2010 APPLICATION FOR WITHHOLDING PROPRIETARY INFORMATION FROM PUBLIC DISCLOSURE
| |
| | |
| ==Subject:==
| |
| SG-CDME-09-4-P, Rev. 0, "Examination of Steam Generator Tubes Removed from Vogtle Unit 1" (Proprietary)
| |
| The proprietary information for which withholding is being requested in the above-referenced report is further identified in Affidavit CAW-10-2731 signed by the owner of the proprietary information, Westinghouse Electric Company LLC. The affidavit, which accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's regulations.
| |
| Accordingly, this letter authorizes the utilization of the accompanying affidavit by Southern Nuclear Operating Company.
| |
| Correspondence with respect to this application for withholding or the accompanying affidavit should reference CAW-10-2731, and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.
| |
| Very truly yours,
| |
| *-\J. A. Gresham, Manager Regulatory Compliance and Plant Licensing cc: G. Bacuta (NRC OWFN 12E-1)
| |
| Enclosures
| |
| | |
| CAW-10-2731 AFFIDAVIT STATE OF CONNECTICUT:
| |
| ss COUNTY OF HARTFORD:
| |
| Before me, the undersigned authority, personally appeared Michael J. Gancarz, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of Westinghouse Electric Company LLC ("Westinghouse"), and that the averments of fact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief:
| |
| C'IL Michael J. Gancarz, Product Manager Systems and Equipment Engineering II Sworn to and subscribed before me this 1 4 t01 day of January ,2010 Nary Public My Commission Expires: F13/( J /
| |
| | |
| 2 CAW- 10-2731 (1) 1 am Product Manager, Systems and Equipment Engineering 11, in Nuclear Services, Westinghouse Electric Company LLC (Westinghouse), and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.
| |
| (2) 1 am making this Affidavit in conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations and in conjunction with the Westinghouse Application for Withholding Proprietary Information from Public Disclosure accompanying this Affidavit.
| |
| (3) 1 have personal knowledge of the criteria and procedures utilized by Westinghouse in designating information as a trade secret, privileged or as confidential commercial or financial information.
| |
| (4) Pursuant to the provisions of paragraph (b)(4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.
| |
| (i) The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse.
| |
| (ii) The information is of a type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence. The application of that system and the substance of that system constitutes Westinghouse policy and provides the rational basis required.
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| Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:
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| (a) The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of
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| 3 CAW- 10-2731 Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.
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| (b) It consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage, e.g., by optimization or improved marketability.
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| (c) Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.
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| (d) It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.
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| (e) It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse.
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| (f) It contains patentable ideas, for which patent protection may be desirable.
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| There are sound policy reasons behind the Westinghouse system which include the following:
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| (a) The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors. It is, therefore, withheld from disclosure to protect the Westinghouse competitive position.
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| (b) It is information that is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information.
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| (c) Use by our competitor would put Westinghouse at a competitive disadvantage by reducing his expenditure of resources at our expense.
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| 4 CAW-10-2731 (d) Each component of proprietary information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage. If competitors acquire components of proprietary information, any one component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage.
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| (e) Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries.
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| (f) The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage.
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| (iii) The information is being transmitted to the Commission in confidence and, under the provisions of 10 CFR Section 2.390, it is to be received in confidence by the Commission.
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| (iv) The information sought to be protected is not available in public sources or available information has not been previously employed in the same original manner or method to the best of our knowledge and belief.
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| (v) The proprietary information sought to be withheld in this submittal is that which is appropriately marked in, SG-CDME-09-4-P, Rev. 0, "Examination of Steam Generator Tubes Removed from Vogtle Unit 1" (Proprietary), for submittal to the Commission, being transmitted by Southern Nuclear Operating Company and Application for Withholding Proprietary Information from Public Disclosure, to the Document Control Desk. The proprietary information as submitted by Westinghouse is that associated with steam generator manufacturing parameters and test setup methodology.
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| This information is part of that which will enable Westinghouse to provide steam generator design, testing and licensing defense services to utilities worldwide.
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| 5 CAW-10-2731 Further this information has substantial commercial value as follows:
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| (a) Westinghouse plans to sell the use of the information to its customers for the purpose of offering steam generator design, testing and licensing defense services.
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| (b) The information requested to be withheld reveals the distinguishing aspects of a methodology which was developed by Westinghouse.
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| Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar steam generator design, testing and licensing defense services for commercial power reactors without commensurate expenses. Also, public disclosure of the information would enable others to use the information to meet NRC requirements for licensing documentation without purchasing the right to use the information.
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| The development of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money.
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| In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended.
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| Further the deponent sayeth not.
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| PROPRIETARY INFORMATION NOTICE Transmitted herewith are proprietary and/or non-proprietary versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific review and approval.
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| In order to conform to the requirements of 10 CFR 2.390 of the Commission's regulations concerning the protection of proprietary information so submitted to the NRC, the information which is proprietary in the proprietary versions is contained within brackets, and where the proprietary information has been deleted in the non-proprietary versions, only the brackets remain (the information that was contained within the brackets in the proprietary versions having been deleted). The justification for claiming the information so designated as proprietary is indicated in both versions by means of lower case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information. These lower case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).
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| COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse copyright notice. The NRC is permitted to make the number of copies of the information contained in these reports which are necessary for its internal use in connection with generic and plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, permit, order, or regulation subject to the requirements of 10 CFR 2.390 regarding restrictions on public disclosure to the extent such information has been identified as proprietary by Westinghouse, copyright protection notwithstanding. With respect to the non-proprietary versions of these reports, the NRC is permitted to make the number of copies beyond those necessary for its internal use which are necessary in order to have one copy available for public viewing in the appropriate docket files in the public document room in Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient for this purpose. Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.}}
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