ML15054A008
| ML15054A008 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 02/16/2015 |
| From: | David Gudger Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP2L 2567 | |
| Download: ML15054A008 (26) | |
Text
Ar7Exelon Generation. 200 Exelon Way Kennett Square, PA 19348 www.exeloncorp.com 10 CFR 50.55a NMP2L 2567 February 16, 2015 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Nine Mile Point Nuclear Station, Unit 2 Renewed Facility Operating License No. NPF-69 NRC Docket No. 50-410
Subject:
End of Interval Relief Request Associated with the Second 10-Year Risk-Informed ISI Inspections In accordance with 10 CFR 50.55a(g)(5)(iii), Exelon Generation Company, LLC (Exelon) is requesting relief from the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components." This relief applies to the second 10-year ISI interval which began on April 5, 1998 and ended on April 4, 2008. The second 10-year ISI interval complied with the ASME Boiler and Pressure Vessel Code, Section Xl, 1989 Edition with no addenda.
During a self-assessment of the ASME Section XI program, the station discovered that it did not submit the required request for relief for limited coverage risk-informed examinations performed during the second ten-year inspection interval which ended April 4, 2008. All required examinations were performed as scheduled and to the maximum extent possible.
The condition was entered into the station's corrective action program.
There are no regulatory commitments in this letter.
If you have any questions concerning this letter, please contact Tom Loomis at (610) 765-5510.
Respectfully, Mantgr - Licensing & Regulatory Affairs Exelon Generation Company, LLC A 047
End of Interval Relief Request Associated with the Second 10-Year Risk- Informed ISI Inspections February 16, 2015 Page 2
Attachment:
Request for Relief 21SI-012 cc: Regional Administrator, Region I, USNRC USNRC Senior Resident Inspector Project Manager [Nine Mile Point] USNRC
Attachment Request for Relief 21SI-012
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Second Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 1 of 23) 1.0 ASME CODE COMPONENTS AFFECTED See Table 1.
2.0 APPLICABLE CODE EDITION AND ADDENDA The second 10-year Inservice Inspection (ISI) interval program was based on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV)
Code,Section XI, 1989 Edition with no addenda and was applicable from April 5, 1998 thru April 4, 2008. The examination requirements for Class 1 and 2 piping welds at Nine Mile Point Nuclear Station, Unit 2 for the second ISI interval were governed by the Risk-Informed Inservice Inspection (RI-ISI) program. The RI-ISI alternative was approved by the NRC in a Safety Evaluation dated May 31, 2001 (Accession No. ML011420195).
The RI-ISI program was developed in accordance with the Electric Power Research Institute (EPRI) Topical Report TR-1 12657, Revision B-A, "Revised Risk-Informed Inservice Inspection Evaluation Procedure." The RI-ISI program was also implemented in a manner consistent with ASME Code Case N-578-1, "Risk-Informed Requirements for Class 1, 2 or 3 Piping, Method B."
3.0 APPLICABLE CODE REQUIREMENT The Nine Mile Point Nuclear Station, Unit 2 relief request dated October 16, 2000 stated "In instances where a location may be found at the time of the examination that does not meet >90% coverage, the process outlined in the EPRI TR will be followed." EPRI TR-112657, Section 6.4, Item 4 states "A new relief request will be generated for any RI-ISI piping element selection for which greater than 90 percent examination coverage is not achieved." EPRI TR-1 12657, Section 6.4, also goes on to state "Consistent with the requirements of Code Case N-460 [60], an examination will be considered limited if less than or equal to 90 percent coverage is obtained." This relief request addresses piping element selections for the second ISI interval where <90% of the examination volume was obtained.
4.0 IMPRACTICALITY OF COMPLIANCE Pursuant to 10 CFR 50.55a(g)(5)(iii), relief is requested from the required 100%
volumetric examination of the RI-ISI piping elements in Table 1, on the basis that conformance with these Code requirements is impractical due to component configuration and access restrictions.
5.0 BURDEN CAUSED BY COMPLIANCE Due to the component configurations, portions of the code required examination volume could not be completely examined. Performance Demonstration Initiative (PDI) qualified procedures were used to perform examinations on these welds, and when applicable, one sided examination procedure guidance was implemented. The installed components would need to be re-designed in order to obtain coverage greater than 90%. Re-design and installation of new components would be impractical due to the personnel exposure and cost that would be incurred in completing modifications.
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Second Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 2 of 23)
Nine Mile Point Nuclear Station, Unit 2 requests relief from 100% volumetric examination of the piping element butt welds defined in Table 1.
6.0 PROPOSED ALTERNATIVE AND BASIS FOR USE No alternate provisions are practical for the subject welds. Examinations were performed to the maximum extent practical with the best available methods at the time of the examination.
7.0 DURATION OF PROPOSED ALTERNATIVE This relief is requested for the second 10-year ISI interval for Nine Mile Point Nuclear Station, Unit 2 which ended on April 4, 2008.
8.0 PRECEDENTS Similar relief requests have been approved for:
- 1) The Limerick Generating Station, Units 1 and 2 (Relief Request RR-34) in a U.S.
Nuclear Regulatory Commission Safety Evaluation Report dated January 27, 2009.
- 2) The Peach Bottom Atomic Power Station, Units 2 and 3 (Relief Request 13R-48) in a U.S. Nuclear Regulatory Commission Safety Evaluation Report dated August 27, 2010.
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 3 of 23)
Table 1 Code Code %
Weld Number Description Class Category Item System Method Coverage Reason for Limitation Reactor Core 21CS-57-07-SW030 Valve-to-Pipe 1 R-A R1.20 Isolation UT 85 Pipe-to-valve configuration. See Figure 1.
Cooling Obstruction due to adjacent 21SC-322B-SW005 Tee-to-Reducer 1 R-A R1.11 Reactor Vessel UT 37 welded ASME Code plate and Instrumentation small bore tee-to-reducer configuration. See Figure 2.
Reactor Pipe-to-valve configuration only 2RCS-64-00-FWA07 Valve-to-Pipe 1 R-A R1.16 Recirculation UT 50 qualified for single-sided exam coverage. See Figure 3.
Unable to perform parallel scans on safe-end side due to radial 2RPV-KB32 Nozzle N1 6-to-Safe 1 R-A R1 .16 High Pressure UT 75 hoop shrinkage. 100% coverage End Core Spray for detection of circumferential flaws was achieved with axial scans. See Figure 4.
Standby S Liquid Pipe-to-valve configuration only 2SLS-88A-FW013A Valve-to-Reducer 1 R-A R1.11 Control System UT 50 qualified for single-sided exam Control__Systemcoverage. See Figure 5.
Standby Liquid Weld-O-Let configuration. See 2SLS-88A-FW042A Pipe-to-Weld-O-Let 1 R-A Ri.11 Control System UT 75 Figure 6.
The curvature of the intrados on 2WCS-09 T P 1 RA Ri.16 Reactor Water UT 89.5 a tee fitting limits scanning from SW021 eeto-pe - Clean up one side of the weld for 3" in the radius area. See Figure 7.
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 4 of 23)
Table 1 Code Code %
Weld Number Description Class Category Item System Method Coverage Reason for Limitation The curvature of the intrados on 2WCS-09 Reactor Water a tee fitting limits scanning from SW022 Pipe-to-Tee 1 R-A R1.16 CleanuUT 89.5 one side of the weld for 3" in the radius area. See Figure 8.
The curvature of the intrados on 2WCS-09 P T RA R116 Reactor Water UT 89.5 a tee fitting limits scanning from SW024 ipetoee 1 - Cleanup one side of the weld for 3" in the radius area. See Figure 9.
2WCS-09 Reactor Water Flange-to-pipe configuration only SW025 Flange-to-Pipe 1 R-A R1.16 Cleanup UT 50 qualified for single-sided exam coverage. See Figure 10.
The curvature of the intrados on 2WCS-09 1R.16 Reactor Water UT 89.5 a tee fitting limits scanning from SW031 Cleanup one side of the weld for 3" in the radius area. See Figure 11.
The curvature of the intrados on 2WCS-09 Reactor Water a tee fitting limits scanning from SW032 Tee-to-Pipe 1 R-A R.16CleanupUT 78.75 one side of the weld for 6" in the radius area. See Figure 12.
The curvature of the intrados on 2WCS-09 Reactor Water a tee fitting limits scanning from SW034 Te-t-Pp one side of the weld for 3" in the radius area. See Figure 13.
The curvature of the intrados on 2WCS-09 PitT 1 RA R1.16 Reactor Water UT 89.5 a tee fitting limits scanning from SW026 ipeoee - Cleanup one side of the weld for 3" in the radius area. See Figure 14.
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 5 of 23)
Table 1 Code Code %
Weld Number Description Class Category Item System Method Coverage Reason for Limitation The curvature of the intrados on 2WCS-09 PtT 1 RA Ri.16 Reactor Water UT 89.5 a tee fitting limits scanning from SW029 Cleanup one side of the weld for 3" in the radius area. See Figure 15.
The curvature of the intrados on 2WCS-09 P T 1 RA Ri.16 Reactor Water UT 89.5 a tee fitting limits scanning from SW030 Cleanup one side of the weld for 3" in the radius area. See Figure 16.
2WCS-09 Reactor Water Flange-to-pipe configuration only SW033 Flange-to-Pipe 1 R-A R1.16 Cleanup UT 50 qualified for single-sided exam coverage. See Figure 17.
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 6 of 23)
Figure 1 Weld Identification: 21CS-57-07-SWO30 Weld Configuration: Valve 21CS*V156-to-Pipe Limitation: Pipe-to-valve configuration only qualified for single-sided exam coverage.
Search Units: 45 degree shear wave, 0.375" round, 5 MHz.
60 degree shear wave, 0.375" round, 5 MHz.
70 degree shear wave, 0.375" round, 5 MHz.
Materials: Valve - SA 216 WCB; Pipe - SA 106 Gr. B Thickness: 0.432" Coverage Achieved: 85%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are less than 0.50-inch thick were examined using 45-degree shear waves, 60-degree shear waves, and 70-degree shear waves. Single-sided access obstructed the circ scan on the upstream side of the weld. Therefore, the maximum Code coverage that may be claimed is 85%.
Scan Volume % Coverage Axial UPST 100%
AMlat DNST 100%
Circ UPST 41%
Cite'SO------
DNS_T - 100%
Total Coverage: 85%
CIM Exams No exam performed on upst $tde due to valve configuration.
Catc:
" Length of exam box = ".r
" Upst exam box a 1.7 12, = 0.85' mutIRII
- Examined 0.35" of 0.85' = 41%
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class I Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 7 of 23)
Figure 2 Weld Identification: 21SC-322B-SWO05 Weld Configuration: Tee-to-Reducer Limitation: Obstruction due to adjacent Code nameplate and small bore tee-to-reducer configuration.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
60 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Tee - SA-1 82 F316L; Reducer - SA-1 82 F316L Thickness: Nominal 0.218" (Fitting 0.46"T)
Coverage Achieved: 37%
Note: 4" of the upstream axial exam is obstructed by the welded Code nameplate.
Code credit could not be claimed for the parallel scans due to the small tee-to-reducer configuration. Circ scans were performed with qualified 45 degree search units, but did not impinge on the inner diameter. 37.7 degrees would have been required to contact the inner diameter, which was not qualified at the time of examination. (Nominal OD fitting 2.375"-0.46"-0.46"=1.455" ID fitting)
(1.4755"/2.375"=0.6126") Inverse sine of 0.6126=37.7 degrees.
Code Pie,. *S I0c°/o 5.0 I*-,: L4' L0* O1 /g, CC.w 0%
0 o3
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 8 of 23)
Figure 3 Weld Identification: 2RCS-64-00-FWA07 Weld Configuration: Valve 2RCS*HYV1 7A-to-Pipe Limitation: Pipe-to-valve configuration only qualified for single-sided exam coverage.
Search Units: 45 degree shear wave, 0.5" round, 1.5 MHz.
60 degree refracted longitudinal wave, 2(15x25) mm rectangular, 2.0 MHz.
Materials: Valve - SA 351; Pipe - SA 358, Type 316 Thickness: 1.3" Coverage Achieved: 50%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are greater than 0.50-inch thick were examined using 45-degree shear waves and a longitudinal wave search unit that provided adequate coverage on the far side of the weld. 10 CFR 50.55a(b)(2)(xv)(A)(2) requires that when examination from both sides is not possible on austenitic welds, full coverage from a single side may be claimed only after completing a successful single-sided Appendix VIII demonstration using flaws on the opposite side of the weld. Since the industry has not qualified single-sided examinations, Nine Mile Point Nuclear Station, Unit 2 performs best-effort examinations to the extent practical and does not claim Code coverage on the far side of the weld.
Therefore, the maximum Code coverage being claimed is 50%.
VALVE PIPE
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 9 of 23)
Figure 4 Weld Identification: 2RPV-KB32 Weld Configuration: Nozzle N1 6-to-Safe End Limitation: On safe-end side, due to radial hoop shrinkage, unable to perform parallel scans. 100% coverage for detection of circumferential flaws was achieved with axial scans.
Search Units: 45 degree shear wave, 0.5" round, 1.5 MHz.
45 degree refracted longitudinal wave, 2(15x25) mm rectangular, 1.5 MHz.
60 degree refracted longitudinal wave, 2(15x25) mm rectangular, 1.5 MHz.
Materials: Nozzle - SA-508 Class 2; Safe End - SB-1 66 inconel Thickness: 1.35" Coverage Achieved: 75%
Note: 100+50=150/2=75%
45-8, 45L. CoMWage Pof - Ctcun* , Sa Direcio
- 50%* o*trage fotre det*fcn of aiaity odentad Raw was cblaied The ASME Code requhed samitm volume is the boww 113weld volume and base maedal for a 4s of l14 Wxl frm eac weld toe.
Inaddbon toihe ASMECods required eaxwnrlon volumie. lhe caiiea wld w okome sead butter amrail Is additionally evaluated durft dab wusi toirkeft bienicatio frommkn d.wa to deeps retleclta whoe reduced Insde surface urbas*- responses maybe encounteaed In addition to fit ASME Code required exsirimartln v~lutn. 11 cnaplats weld vohu,. and buller malaria Is adllnl evkaa rhn dat anli Io Idlertlty indicaton Iran ani-,wal to deepe t elaccelites redmmucedirside aufc ulrsn repne ros bearoune The sufaceco*tdlon Ikdita*on(radt shvdw oi safe end side oftlie compontel) reduced the efflecller of a4ial cenue in both bees dWetfinn howet*e k ierreaton of lseaaxuiaton volume w acied us unfctd portions h ea a d The eranteeatdon pocedure used fo qMe dlt sge of sicdae ino Wfr cc a red! iOn" lwtas dtIMAO -
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 10 of 23)
Figure 5 Weld Identification: 2SLS-88A-FW01 3A Weld Configuration: Valve 2SLS*V1 0-to-Reducer Limitation: Single side examination due to configuration. No scans performed on the upstream side due to valve.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Valve - SA1 82 F316L; Reducer - SA1 82 F316L Thickness: 0.2" Coverage Achieved: 50%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are less than 0.50-inch thick were examined using 45-degree shear waves and a 70-degree shear wave search unit that provided adequate coverage on the far side of the weld. 10 CFR 50.55a(b)(2)(xv)(A)(2) requires that when examination from both sides is not possible on austenitic welds, full coverage from a single side may be claimed only after completing a successful single-sided Appendix VIII demonstration using flaws on the opposite side of the weld. Since the industry has not qualified single-sided examinations, Nine Mile Point Nuclear Station, Unit 2 performs best-effort examinations to the extent practical and does not claim Code coverage on the far side of the weld.
Therefore, the maximum Code coverage being claimed is 50%.
'70
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 11 of 23)
Figure 6 Weld Identification: 2SLS-88A-FW042A Weld Configuration: Pipe-to-Weld-O-Let Limitation: Weld-O-Let Configuration Search Units: 45 degree shear wave, 0.375" round, 2.25 MHz.
Materials: Pipe - SA 106 GR B; Weld-O-Let - SA 105 Thickness: 0.68" Coverage Achieved: 75%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are greater than 0.50-inch thick were examined using 45-degree shear waves. When examination from both sides is not possible on carbon steel welds, full coverage from a single side may be claimed only after completing a successful single-sided Appendix VIII demonstration using flaws on the opposite side of the weld. Nine Mile Point Nuclear Station, Unit 2 has qualified a single-sided examination for carbon steel welds. This was the coverage documented during the 2002 refueling outage examination. This component was reexamined during the 2012 refueling outage under the RI-ISI program and the coverage information of 73% (provided on the following page) supports the examination coverage reported in 2002.
2002 Examination Coveraae D ms- c c se At- too% =.I6%-roTAL tJP- NX CAA~ - 0 /7 %-ThTA L DSVAx5SCAF-50*/.: j;.S7%,biAL
- N1T6LAw& '7 5*4 TUTA L
~ AkY'AL ct
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Risk-Informed Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 12 of 23)
Figure 6 (Cont'd) 2012 Examination Coverage 2SLS-88A-FW042A Sketch 1: Code Coverage Sk &h8:eoCoverage: Axial Exam Area: 12
- (1.1" x 0.231) 0.25 in, Examined:
- 0.25 - (0.05 x 0.15)/2 - (0.15 x 0.15)/2 0.24 inW
- 0.24 0.25 =96% Weld-o-let 0.68" M Code Coverage: Circ Exam Area:
" (11"wxO.23")=0.25in 2 12" Examined: Pipe
- (0.55 x 0.23) =0.125 in2 0 0.12510.25 = 50%
Weld-o-let Code Coverage Calc:
0 2"
- Axial = 96% - , ! I
" Circ = 50%
" Total = (96 + 50)/2 = 73%
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 13 of 23)
Figure 7 Weld Identification: 2WCS-09-05-SWO21 Weld Configuration: Tee-to-Pipe Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Tee - SA 403 WP316L; Pipe - SA 312, Type 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=0.79xl 00=79%
79%+1 00%=1 79/2=89.5%
1 t4ODV
',5 of or16 DrpE
- . ... _4,,
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 14 of 23)
Figure 8 Weld Identification: 2WCS-09-05-SW022 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Pipe - SA-312 Type 316L; Tee - SA403 WP 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137' (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=.79x100=79%
79%+1 00%=1 79/2=89.5%
/6* r P*E *E
~ 9 xpZ.
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 15 of 23)
Figure 9 Weld Identification: 2WCS-09-05-SW024 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Pipe - SA 312, Type 316L; Tee - SA 403 WP 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=0.79xl 00=79%
79%+1 00%=1 79/2=89.5%
0Oi P.ZE
-r-:-F I-LOWv efle,(64"c pucl-r
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 16 of 23)
Figure 10 Weld Identification: 2WCS-09-05-SW025 Weld Configuration: Flange-to-Pipe Limitation: Single side examination due to configuration of flange to pipe.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Flange - SA 403 WP 316L; Pipe - SA 312, Type 316L Thickness: 0.337" Coverage Achieved: 50%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are less than 0.50-inch thick were examined using 45-degree shear waves and a 70-degree shear wave search unit that provided adequate coverage on the far side of the weld. 10 CFR 50.55a(b)(2)(xv)(A)(2) requires that when examination from both sides is not possible on austenitic welds, full coverage from a single side may be claimed only after completing a successful single-sided Appendix VIII demonstration using flaws on the opposite side of the weld.
Since the industry has not qualified single-sided examinations, Nine Mile Point Nuclear Station, Unit 2 performs best-effort examinations to the extent practical and does not claim Code coverage on the far side of the weld. Therefore, the maximum Code coverage being claimed is 50%.
b"'0
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 17 of 23)
Figure 11 Weld Identification: 2WCS-09-05-SWO31 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Tee - SA-403 WP 316L; Pipe - SA 312, Type 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=0.79x100=79%
79%+1 00%=1 79/2=89.5%
- 1) £
'L65C, I
/
l V.- ----. 5/
C,
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 18 of 23)
Figure 12 Weld Identification: 2WCS-09-05-SW032 Weld Configuration: Tee-to-Pipe Limitation: The curvature of the 2 intrados' on a tee fitting limits scanning from one side of the weld for 6" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Tee - SA 403 WP 316L; Pipe - SA 312, Type 316L Thickness: 0.337" Coverage Achieved: 78.75%
Note: 14.137" (Circ. of pipe)-6" (Obs.)=8.137'/14.137"=0.575x100=57.5%
57.5%+1 00%=1 57.5/2=78.75%
- . ., . .. : .* . . . . . . . . . .. .E.
f.
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 19 of 23)
Figure 13 Weld Identification: 2WCS-09-05-SW034 Weld Configuration: Tee-to-Pipe Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Tee - SA 403 WP 316L; Pipe - SA 312, Type 316L Thickness: 0.337' Coverage Achieved: 89.5%
Note: 14.137"' (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=0.79x100=79%
79%+1 00%=1 79/2=89.5%
tI*
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 20 of 23)
Figure 14 Weld Identification: 2WCS-09-05-SW026 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Pipe - SA-312 Type 316L; Tee - SA403 WP 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) = 11.137"/14.137"=.79x100=79%
79%+100%=179/2=89.5%
'V how . 1ý Aroc The-(oWCX4 W406
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 21 of 23)
Figure 15 Weld Identification: 2WCS-09-05-SW029 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Pipe - SA-312 Type 316L; Tee - SA403 WP 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=.79x100=79%
79%+100%=179/2=89.5%
, ,4 -, , . * . , ,
... .,:.,., . . f ......
... * -..-., r--T!
~t I~
- , I* , .*
- i * . " *. . ......
I- 1 44 ... i - I
Request for Relief 21SI-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 22 of 23)
Figure 16 Weld Identification: 2WCS-09-05-SWO30 Weld Configuration: Pipe-to-Tee Limitation: The curvature of the intrados on a tee fitting limits scanning from one side of the weld for 3" in the radius area.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Pipe - SA-312 Type 316L; Tee - SA403 WP 316L Thickness: 0.337" Coverage Achieved: 89.5%
Note: 14.137" (Circ. of pipe)-3" (Obs.) =11.137"/14.137"=.79xl 00=79%
79%+100%=179/2=89.5%
- I ,"'I ; / : ' " I a." ..
KI 1 I .1.~
j7r V. j iv
~a I
,4 * ~,,' )
I I ~45(J~
j I~a"" '45
.L Jmp......
- ,',., a
- ~
- -~--
I *. I I a"a4" a a . 4 *.'. ..
4, a, a4
- ~ ~,
~aa
~
~
4 "*
45 a"-..
I"
? ÷* I.........
4- I * * ,*:4a L : *,
"-F ,* .. ,*,*.
- 2*,..=
.*...,:= * . ... ...
U. 'a a,,
Request for Relief 21Sl-012 for Obtaining the Required Percentages During the Fourth Interval for Class 1 Component Inspections In Accordance with 10 CFR 50.55a(g)(5)(iii)
(Page 23 of 23)
Figure 17 Weld Identification: 2WCS-09-05-SW033 Weld Configuration: Flange-to-Pipe Limitation: Single side examination due to configuration of flange to pipe.
Search Units: 45 degree shear wave, 0.25" round, 2.25 MHz.
70 degree shear wave, 0.25" round, 2.25 MHz.
Materials: Flange - SA 403 WP 316L; Pipe - SA 312, Type 316L Thickness: 0.337" Coverage Achieved: 50%
Note: In accordance with Supplement 2 of Appendix VIII, welds limited to single-sided access that are less than 0.50-inch thick were examined using 45-degree shear waves and a 70-degree shear wave search unit that provided adequate coverage on the far side of the weld. 10 CFR 50.55a(b)(2)(xv)(A)(2) requires that when examination from both sides is not possible on austenitic welds, full coverage from a single side may be claimed only after completing a successful single-sided Appendix VIII demonstration using flaws on the opposite side of the weld.
Since the industry has not qualified single-sided examinations, Nine Mile Point Nuclear Station, Unit 2 performs best-effort examinations to the extent practical and does not claim Code coverage on the far side of the weld. Therefore, the maximum Code coverage being claimed is 50%.
....... 2'14 F
-_ ..-' i*-
." "i
...... , i... 14 ,_.
L .""r.,,
... - I."f~
- "...* ........ . "S . .... I` T r . ... ] * - - °t ,""2 "iI " i"*'"
J
-4....... 2- ..14j" II 'I ..I ] . . ....." I; . ........ : . . ... .*""_7 . 7.. 1li
. . . r.. :....
- I I ii *.** /_.1 *. ... :. . .* . .. "' I . .:.. . .'"