LR-N07-0045, Steam Generator Tube ISI Summary Report
| ML070720424 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 03/01/2007 |
| From: | Joyce T Public Service Enterprise Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LR-N07-0045 | |
| Download: ML070720424 (37) | |
Text
PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 V
PSEG Nuclear LLC Technical Specification 6.9.1.5 LR-N07-0045 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Salem Nuclear Generating Station Units 1 and 2 Facility Operating License Nos. DPR-50 and 75 NRC Docket Nos. 50-272 and 50-311
Subject:
2006 Steam Generator Tube ISI Summary Report PSEG Nuclear LLC (PSEG) submits this report in accordance with the requirements of Salem Units 1 and 2 Technical Specification (TS) 6.9.1.5 b. Specifically, TS 6.9.1.5 b.
requires that the complete results of steam generator tube inservice inspections performed during the report period be reported to the Commission.
Attachment I to this letter contains PSEG report in accordance with Technical Specification 6.9.1.5.b Should you have any questions regarding this transmittal, please contact E. H. Villar at (856) 339-5456.
Sincerely, Thomas P. Joyce Site Vice President - Salem 95-2168 REV. 7/99
MAR 01 200 Document Control Desk LR-N07-0045 Page 2 Mr. Samuel Collins, Administrator - Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. R. Ennis, Project Manager - Hope Creek and Salem U. S. Nuclear Regulatory Commission Mail Stop 08B2 11555 Rockville Pike Rockville, MD 20852 USNRC Resident Inspector Office - Salem (X24)
Mr. K. Tosch, Manager IV Bureau of Nuclear Engineering P. O. Box 415 Trenton, NJ 08625
Document Control Desk LR-N07-0045 2006 Steam Generator Tube ISI Summary Report In the Fall of 2006, PSEG Nuclear conducted eddy current examinations on the Salem Unit 2 Steam Generators (SG) during the 15th Refueling Outage (2R15). Outage 2R15 is the last planned in-service inspection of the currently installed (Westinghouse Series
- 51) steam generators. Steam generator replacement is currently planned for the Spring 2008 outage (2R16). In-service inspections were not required or performed on the Salem Unit 1 Steam Generators during 2006.
Overview Commercial operation began in October of 1981. Salem Unit 2 has four Westinghouse Model 51 series steam generators. Each steam generator contains 3388 NiCrFe alloy (Inconel ASME-SB-1 63) U-tubes with an outside diameter of 0.875 inches and a nominal wall thickness of 0.050 inches. The tube support structures consist of seven equally spaced 0.750 inch thick carbon steel support plates, which are drilled with 0.891 inch holes and two sets of anti-vibration bars (AVB) that are located in the U-bend region of the tubes. The AVB bars are made from 0.387 square inch cross-section straight length bar material (Nickel-Chromium iron Alloy 600, chrome plated subsequent to bending) that is bent to a vee form with a 5.00-inch radius at the apex. The tube sheet is 21 inches thick ASME-SA508 Class 2 steel forging with Inconel cladding on the primary side. The tube ends are rolled into the tube plate and welded to the tube plate cladding. All tubes are explosively expanded into the tube sheet holes (a.k.a.
WEXTEX). The expansion includes the entire depth of the tube sheet for both the hot and cold leg sides.
Examinations Performed (Scope)
The eddy current examination scope performed during outage 2R1 5 met or exceeded Salem Unit 2 Technical Specification 3/4.4.6, "Steam Generators" Surveillance Requirements and NEI 97-06 SG Program requirements.
The final scope performed (including expansions) is outlined below:
With the exception of those row 2 through 5 U-bends inspected under Rotating Coil inspection program, a full-length bobbin coil inspection was performed on 100% of the in-service tubes in each steam generator. These inspections provided a seamless tube-end to tube-end inspection (including bobbin and Rotating Coil probes). Note that all row 1 tubes were preventatively plugged during a previous outage.
100% Rotating Coil (+ Point) exam of the rows 2 through 10 U-bends (07C-07H or 07H - 07C) in each steam generator.
1
100% Rotating Coil (+ Point) exam of the Hot Leg (HL) WEXTEX Top of Tubesheet (TI-S) transition regions in each steam generator at an extent of at least +3 inches above and -8 inches below the TTS.
100% Rotating Coil (+ Point) exam of the > 1.0-volt dented HL Tube Support Plate (TSP) intersections at 01 H, 02H and 03H and 20% of the > 1.0-volt dented HL Tube Support Plate (TSP) intersections at 04H in 22, 23 and 24 steam generator. In 21 SG performed 100% Rotating Coil (+ Point) exam of the > 1.0-volt dented HL Tube Support Plate intersections at 01 H, 02H, 03H, 04H and 20% of the > 1.0-volt dented HL Tube Support Plate (TSP) intersections at 05H.
20% (at a minimum) Rotating Coil (+Point) inspection of the > 5 volt dented TSP locations at 04H (05H for SG 21) to 07H, which included all >5 volt dented TSP locations at 04H (05H for SG 21) to 07H that were not inspected since 2R12. Note:
The 04H (05H for SG 21) k1 volt 20% sample TSP inspections (mention previously) is conservatively NOT credited to meet the 04H (05H for SG 21) >5 volt 20%
sample. A separate, non-overlapping population is selected at 04H (05H for SG 21) for the two separate scopes.
20% (at a minimum) Rotating Coil (+Point) inspection of the >2 volt Dings in each SG from TSH +0.5 inches to 07H + 2 inches which shall include all Ž2 volt Dings that were not inspected since 2R12. SG 24 was expanded to include 100% >5 volt Dings from TSH +05 inches to 07H, and SG 21, 22, and 23 included a minimum 20% inspection of all the >5 volt Dings (TSH +0.5 inches to 07H) with Rotating Coil
(+Point).
Rotating Coil (+ Point) examination of previous TSP ligament Indications identified from the 2R14 bobbin coil data and any newly identified TSP ligament indications identified during 2R15.
20% Rotating Coil (+ Point) of > 2.0 volt U-bends Dings (07H to 07C) in each steam generator.
20% Rotating Coil (+Point) of > 1.0 volt dented Anti-Vibration Bar (AVB's) locations in each steam generator.
New AVB wear indications found during 2R1 5 were inspected with Rotating Coil
(+ Point).
New cold leg thinning indications found during 2R1 5 were inspected with Rotating Coil (+ Point).
Examination Results and Technical Specification Classification Consistent with the requirements specified in NEI 97-06 Rev 2, the Unit 2 steam generators met the structural integrity, accident induced leakage and operational leakage performance criteria specified in site procedures ER-AP-420 "Steam Generator Management Program" and ER-AP-420-0051 " Conduct of Steam Generator Management Program Activities" for outage 2R1 5. Table I (see below) summarizes the number of tubes plugged in each steam generator by degradation mechanism. Areva designed Alloy 690 rolled plugs were used to remove these tubes from service, 2
The Technical Specification categorization of each steam generator is listed in the table below and takes into consideration both the Bobbin coil and Rotating Coil inspection results.
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Table I SALEM UNIT 2 R15 Final Indication Summary Location Tube 1 Steam Generato i Total Degradation 2-1 II2-2 II2-3 Axial PWSCC 7
1 3V_ )
8 TSP Circ PWSCC Axial ODSCC 1
1 2
Circ ODSCC 1
1 Axial PWSCC 1
2 7
10 Tubesheet Axial ODSCC 1
1 Circ PWSCC 1
Crc ODSCC 1
Axial PWSCC U-bends Circ PWSCC Axial ODSCC High Row U-bends AVB Wear >=40%
1 1
4(1) 2 4
Cold Leg Thinning Thinning >=40% or SVI 1
1 3
5 Free Span Axial ODSCC @ Dings 1
1 Total Indications 12 5
6 18 41 Final Tube Repair Summary Steam Generator Total 2-1 2-2 2-3 2-4 Total Tubes with Indications (See Table Above) 12 5
5(1) 17(2) 39 Loose Part 2
7 9
Preventative (Tubes)
Permeability Variation 2
3 5
Ding Signal Above TSH 2
2 Total Tubes Plugged During 21115 16[ 11 10 5
24 55 Notes:
- 1) Tube 32-45 in SG23 contained two AVB wear indications >=40% throughwall.
- 2) Tube 20-64 in SG24 contained two axial PWSCC indications at the 01 H intersection.
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Degradation in the WEXTEX & TTS Transition Zone The WEXTEX transition is the region of the tube where the tube transitions from the expanded tube diameter to the nominal tube diameter and is typically located near the top of the tubesheet. The bottom of the WEXTEX transition (BWT) is the first point of contact between the tube and the tubesheet. In this region, both Primary Water Stress Corrosion Cracking (PWSCC) and Outside Diameter Stress Corrosion Cracking (ODSCC) have been observed with PWSCC being the prominent damage mechanism at Salem Unit 2.
There were a total of 13 detected indications in the WEXTEX & TTS Transition Zone inspections performed in all four steam generators. A total of 10 PWSCC Axial indications, affecting 10 tubes, were identified in the hot leg WEXTEX region. In addition, one PWSCC circumferential indication, one ODSCC circumferential indication, and one ODSCC Axial indication were also detected in the WEXTEX & TTS Transition Zone (also see Table 2 below). It should be noted that all in-service tubes received the minimum +Point inspection extent of TSH +3 inches to TSH -8 inches, and all tubes were verified for inspection depth greater than or equal to the W* Distance as defined in Salem Unit 2 TS (Amendment 256).
All indications were physically located below the TTS, as shown in Table 2. Structural performance criterion for indications below the TTS are met based on the fact that the tubesheet prevents burst. All tubes identified with this degradation were plugged.
Leakage calculations for the indications in the WEXTEX expansion are performed in accordance with Salem Unit 2 Tech Specs (Amendment 256) requirements, and are summarized as follows:
Each SG is assessed for Main Steam Line Break (MSLB) leakage individually, and the SG with the most calculated leakage is conservatively assigned (assumed) as the affected SG. Calculating of the Condition Monitoring (CM) and the Operational Assessment (OA) leakage for each SG is in accordance with the following (LCR S05-07
{Amendment 256}, TS 4.4.6.5.b.4):
Postulated SLB Leakage = Assumed Leakage 0 inches-8 inches <TTS + Assumed Leakage 8 inches-12 inches <TTS + Assumed Leakage >12inches <TTS Assumed Leakage 0 inches - 8 inches <TTS is the postulated leakage for indications that are deemed via flaw depth estimation techniques to be 100% through wall, and therefore present a potential leak path. This term is applicable to detected indications during an in-service inspection and potentially undetected indications in the steam generator tubes left in service between 0 inches and 8 inches below the top of the tubesheet (TTS). Since tubes with indications detected between 0 inches and 8 inches below the TTS are plugged upon detection, the calculation of this term for the assessment of SLB leakage for the subsequent operation cycle following an in-service inspection only requires consideration of potentially undetected indications. The calculation of this term for the assessment of Steamline Break (SLB) leakage for the 5
previous operation cycle, following an in-service inspection, requires consideration of both detected and potentially undetected indications.
Assumed Leakage 8 inches -12 inches <TTS is the conservatively projected leakage in steam generator tubes between 8 inches and 12 inches below the TTS. Implementation of Technical Specification inspections do not require tube inspection below the W*
distance, therefore the methodology for conservatively calculating the population of indications between 8 inches and 12 inches below the TTS is provided by fitting a regression line to the cumulative inspection data (detected indications) from all SGs and projecting the number of indications (to minus 12 inches below TTS) using a 95-percent probability prediction bound. The cumulative indications from all steam generators are conservatively assumed to occur in one SG. The conservative leakage rate for the indications between 8 inches and 12 inches is 0.0033 gpm multiplied by the number of projected indications (as discussed in Amendment 256). The leak rate of indications detected between 8 inches and 12 inches are bounded by the projected total discussed above, assuming that the inspection results for detected indications do not contradict the calculated population as described previously.
Assumed Leakage >12 inches <U-S is the calculated leakage from the steam generator tubes left in service below 12 inches from the top of the tubesheet. This is 0.00009 gpm times the number of tubes left in service in the steam generator.
WEXTEX Summary The indications located from 0 to 8 inches below the Hot Leg (HL) WEXTEX (Tubesheet region) were evaluated for leakage integrity based on the +Point voltage thresholds provided in EPRI Report 1007904, Steam Generator In Situ Pressure Test Guidelines.
All of the indications (see Table 2 below) detected in the WEXTEX region are well below the leakage thresholds, therefore the CM MSLB leak rate contribution is 0 (zero) gpm from indications detected during 2R15 within the WEXTEX region. Since inspections performed in the WEXTEX region utilized +Point inspections, a probe capable of detecting all forms of degradation in the tubesheet region, potentially undetected indications within the first 8 inches of the TTS would also be reasonably assured of not providing any significance for normal operation or accident (MSLB) leak potential.
Therefore, the CM MSLB leak rate from detected indications, and OA MSLB leak rate from potentially undetected indications is 0 (zero) gpm.
The potential leakage (or leak rate) for the undetected indications in the second zone (Assumed Leakage 8 inches to 12 inches <TTS) is estimated by calculating the population of indications between 8 inches and 12 inches below the TTS, and is provided by fitting a regression line to the cumulative inspection data (detected indications) from all SGs and projecting the number of indications (to minus 12 inches below TTS) using a 95-percent probability prediction bound. The cumulative indications from all steam generators are conservatively assumed to occur in one steam generator.
A review of Table 2 indicates that a majority of the WEXTEX indications are near the TTS expansion transition, and therefore exclusion of the expansion transition indications would be expected to provide the best (conservative) dataset for estimating indications 6
at deeper depths because of the significantly higher residual surface stresses associated with the expansion transition (Amendment 256, Westinghouse LTR-CDME-05-30-NP). A best fit regression of the cumulative Salem WEXTEX indications (including 2R15 indications), with the expansion transition excluded (0 inches to 0.99 inches below TTS) is provided in Figure 1 below. Indication totals for the 1 inch through 7 inch (the 7 inch bin includes 7 inches to 8 inches, and also includes the circumferential indication located at approximately 8.09 inches below TTS) bins below the TTS were used for the regression analysis as this range excludes the expansion transition effect on initiation and considers all historical indications in the applied nominal +Pt inspection program of 8 inches below TTS. Note that the 1 inch below the TTS bin of the x-axis on Figure 1 represents the elevation range from -1.00 inches to
-1.99 inches below the TIS. This updated regression, using 2R1 5 data, conservatively estimates a maximum of 20 indications would be expected to reside in the 8 inch to 12 inch region of all SGs, and are conservatively assumed to be in one SG. The conservative leakage rate for the indications between 8 inches and 12 inches is 0.0033 gpm multiplied by the number of estimated (from discussion above) indications.
Also see Table 3 for further details of the estimated leakage (leak rate) for the 8 to 12 inch WEXTEX region. The CM and OA MSLB leak rate potential for 8 inches to 12 inches is conservatively estimated as approximately 0.066 gpm.
For the region more than 12 inches below the WEXTEX transition (Assumed Leakage
>12inches <TIS), a leak rate of 0.00009 gpm for each in-service tube is conservatively assumed in accordance with Amendment 256. This leak rate is conservative since it assumes that the tube is completely severed at this point (12 inches below the TTS).
See Table 3 for details of the estimated leakage (leak rate) for the region more than 12 inches below the WEXTEX transition.
Using the methodologies described above, a conservative estimate of HL WEXTEX accident leakage (MSLB) was calculated for each steam generator. This resulted in a total postulated leak rate for the limiting SG of approximately 0.349 GPM. See Table 3 for details of the estimated CM and OA leakage for the HL WEXTEX region. In addition, the indications detected within the HL WEXTEX region were consistent with the expectations regarding the number of flaws and flaw severity. This is further emphasized by the fact that the indications detected were all relatively trivial (based on measured indication voltage, lengths, and quantity), and that the indications were predominantly near the expansion transition (as typically expected from experience).
Thus, the methodology described above is conservative and provides reasonable assurance for tube integrity and estimating potential leakage within the WEXTEX region.
In addition to the primary to secondary (P-S) leakage estimated from the WEXTEX region, leakage from the tube plugs themselves was also considered. SG 24 contains the most plugged tubes in any single SG (386 tubes / 772 plugs), and applying a conservative leak rate (Bounding value selected from conservative vendor plug qualification, leakage adjusted to room temperature conditions per plug of -3.2 x 10_6 gpm, applicable to both accident and normal operating conditions) to all installed plugs yields a leak rate for SG 24 of approximately 0.00247 gpm or 3.56 gpd. Furthermore, 7
the Salem SGs have a total of 1155 tubes plugged in all SGs (2310 plugs), and therefore a conservative estimate of tube plug leakage would lead to a total of approximately 0.00739 gpm from all four SGs. However, since the majority of the Salem Unit 2 SG tubes have been preventatively plugged or plugged with degradation much less than through-wall, the potential for a leak path to the secondary side is relatively negligible. This is further supported by cycle 15 primary to secondary leakage monitoring, which did not detect any significant leakage (P-S leakage below detection thresholds, or essentially non-existent). Therefore, significant tube plug leakage has not been substantiated. No other potential sources of primary to secondary (P-S) leakage were identified based on degradation detected during outage 2R15 (e.g., all other damage mechanisms were not through-wall and well below leakage screening criteria provided from EPRI Steam Generator In Situ Pressure Test Guidelines). Therefore, the conservatively postulated accident leakage (MSLB) from all sources leads to a total estimated leak rate less than approximately 0.36 gpm for the worst-case steam generator, and total for all SGs. The total postulated accident leakage is estimated to be much less than the total allowable for all SGs (1 gpm), and any single SG (0.6 gpm).
Normal operation P-S leakage is also expected to be negligible as compared to the operational leakage limit.
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Table 2 WEXTEX Region Service Induced Degradation Detected at 2R15 UCT to W.
W* Insp TTS Length Dist UCT Ext wrt CM (0.22" UCT (0.12" to BWT UCT Below UCT BWT Flexible Crack Total uncert below W*
uncert (0.28" W* Length Below Inspect (0.09" W*
Insp Ext CM Leak SG Row Col Ind Volts Type Crack # MD LCT UCT Length Length incl)
TTS ZONE incl)
BWT uncert incl)
?
BWT?
Extent uncert inc)
Length Satisfied?
Rate 212 4 S~ý 1CIJ 0.37 IDSCI I[
147 1-8.09 1-8.091 0.2 10.2 1NA N A IB3 17.12 1-0.3 1 NA NA
[ NA
[-9.42 1
ýNA INA]I Yes 000 21 130 136 1 SAI 0.65 ID SAI 1 1
143 1-0.54 1-0.431 0.11 1 0.11 1 0.21 1 Yes I B4 7.12
-0.371
-0.22 No No
-9.20 18.74 7.12 Yes 0.000 22 5
4 A
0.38 ID SAI 1 159 1 29
-. 5 0.131 0.131 2.631 YesI B1i 7.12
-.0.271 2.30
[ No
[ Yes 1 8.03i1 7.6717.12i1 Yes
~0.000 22 6
60 1 -0.32 1-0.23 0.09 0.09 0.01 Yes B2 7.12
-0.24
-0.29 No No
-8.47 8.14 7.12 Yes 0.000 23 12[461SCI[0.15 ODSCI 1
1
-0.311-0.31 0.29 0.29 B1 7.12 1"0.351 NA I
NA I
NA 1 -9.21 [ NA [ NA Yes 0.000 24 6
11 SAI 0.10 IDSAI 1
47
-0.30 -0.23 0.07 0.07 0.01 Yes A
7.12
-0.09
-0.14 No No
-9.41 9.23 7.12 Yes 0.000 24 10 77 SAI 0.17 OD SAI 1
47
-0.36 -0.28 0.08 0.08 0.06 Yes B4 7.12
-0.26
-0.26 No No
-8.42 8.07 7.12 Yes 0.000 24 14 5
SAIl 0.35 ID SAI 1
36
-0.80 -0.67 0.13 0.13 0.45 Yes A
7.12
-0.29 0.10 No Yes
-9.41 9.03 7.12 Yes 0.000 24 21 6
14
-0.69 -0.62 0.07 0.07 0.40 Yes A
7.12
-0.22 0.12 No Yes
-9.32 9.01 7.12 Yes 0.000 24 23 19 SAI 0.35 ID SAI 1
38
-1.72
-1.63 0.09 0.09 1.41 Yes A
7.12
-0.20 1.15 No Yes
-9.36 9.07 7.12 Yes 0.000 24 23 54 SAI 0.38 ID SAI 1
41
-0.38 -0.27 0.11 0.11 0.05 Yes B3 7.12
-0.24
-0.25 No No
-9.89 9.56 7.12 Yes 0.000 24 30 64 SAI 0.78 ID SAI 1
55
-0.43 -0.23 0.20 0.20 0.01 Yes A
7.12
-0.22
-0.27 No No
-8.89 8.58 7.18 Yes 0.000 24 33 25 SAI 0.66 IDSAI 1
73
-0.38 -0.28 0.10 0.10 0.06 Yes A
7.12
-0.11
-0.11 No No
-9.79 9.59 7.12 Yes 0.000 Notes:
- 1) PSEG is not licensed to apply the Flexible W* Criteria. However, the CM Flexible W* Length is provided to show that the required inspection extent accounting for the flaw lengths is also satisfied. The term "CM" is added to the Flexible W* Length heading to signify that the growth portion of the Flexible W* criteria is not included since Salem does not return any of these flaws to service.
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Figure 1 Salem 2 PWSCC Elevation Prediction 0
- 0 130 120 110 100 90 80 70 60 50 40 30 20 10 0
0 1
2 3
4 5
6 7
8 Depth Below the WiS 9
10 11 12 13 10
Table 3 2R15 Leakage Assessment for Tubesheet Indications In-Service Tube Counts I SG21 I SG22 I SG23
[§G247I No. of In-Service Tubes Pre-2R15 3138 3139 3149 3026 Plugged During 2R15 16 10 5
24 No. of In-Service Tubes Post-2R15 3122 3129 3144 3002 CM Leakage Assessment for Tubesheet Indications Location Range Steam Generator SG21 SG22 SG23 SG24 TSH +0" to TSH -8" 0
0 0
0 TSH -8" to TSH -12" 0.066 0.066 0.066 0.066 Below TSH -12" 0.28242 0.28251 0.28341 0.27234 Total CM Tubesheet Leakage 0.34842 0.34851 0.34941 0.33834 OA Leakage Assessment for Tubesheet Indications Location Range Steam Generator SG21 SG22 SG23 SG24 TSH +0" to TSH -8" 0
0 0
0 TSH -8" to TSH -12" 0.066 0.066 0.066 0.066 Below TSH -12" 0.28098 0.28161 0.28296 0.27018 Total OA Tubesheet Leakage 0.34698 0.34761 0.34896 0.33618 Note: The CM leakage below 12 inches uses the pre-2R15 tubes in-service count, and the OA leakage below 12 inches uses the post-2R1 5 tubes in-service count.
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SCC at HL TSP Intersection Inspections There were a total of 11 axial PWSCC indications at TSP locations (8 at 01 H, 2 at 02H, and 1 at 03H). Two axial ODSCC indications at TSP locations were observed, one at the 01 H elevation and the other at the 02H elevation. The table below shows the tubes plugged for TSP SCC. The tubes repaired for Stress Corrosion Cracking at dented HL TSP locations are shown in the table below:
TSP 2R15 Dent Damage SG Tube ID Indications Location Voltage Mechanism 21 R10C12 SAI 01H 2.06 PWSCC 21 R12C13 SAI 02H 2.88 PWSCC 21 R20C27 SAI 01H 2.33 ODSCC 21 R19C28 SCI 01H 3.09 ODSCC 21 R21C37 SAI 03H 1.23 PWSCC 21 R5C38 SAI 01H 1.03 PWSCC 21 R5C41 SAI 01H 1.13 PWSCC 21 R6C41 SAI 01H 2.14 PWSCC 21 R6C65 SAI 02H 1.76 PWSCC 22 R9C56 SAI 01H 1.28 PWSCC 24 R12C4 SAI 01H 2.28 PWSCC N/A - bobbin 24 R20C64 (2) SAI's 01H DSI of 1.1 volt PWSCC 24 R23C82 SAI 02H 1.08 ODSCC Anti-vibration Bar (AVB) Wear AVB wear indications are plugged if bobbin indicates a depth -- 40% TW. Tubes with degradation less than 40% TW may be left in service, using the bobbin sizing technique.
A total of seven tubes were repaired for this damage mechanism. The table below lists the tubes plugged for AVB wear during 2R1 5:
SG Tube ID Indication TSP Location 21 R27C64 40%TW AV3 22 R34C49 40% TW AV4 23 R30C35 41%TW AV2 42% TW AV2 23 R32C45 42%
AV3 43% TW AV3 23 R27C51 43%TW AV2 24 R31C31 40%TW AV3 24 R42C55 40%TW AVl Appendix 1 provides a listing of the AVB percent through-wall indications reported during 2R15.
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Dents and Dings within the U-bend Regions 20% of the > 1 volt dented AVB locations, and > 2 volt ding locations within the U-bend region were inspected with a +Point probe and no degradation was reported.
Cold Leg Thinning (CLT)
Cold leg thinning (CLT) is caused by surface wastage (corrosion) and occurs principally within the confines of the lower cold leg tube support plates on the periphery of the tube bundle. CLT indications are plugged if bobbin indicates a depth of > 40% TW. Tubes with degradation less than 40% through wall (TW) may be left in service, using the bobbin sizing technique.
A total of five tubes were plugged for this damage mechanism as shown in the table below:
SG Tube ID Indication TSP Location DSI Voltage 22 R32C78 58 % TW 02C N/A 23 R11C3 64 % TW 01C N/A 24 R1OC3 9 % *TW 01C
.55 24 R32C16 7 % *TW 03C
.39 24 R29C82 44 % TW 01C N/A
- Low voltage (0.39 - 0.55 volts) bobbin coil DSI's that via Rotating Coil produces a volumetric response typical of cold leg thinning. The percent through wall depth could not be accurately determined with the bobbin coil phase technique due to the influence of tube support plate residual on the signal. The indication was sized with using a bobbin coil amplitude curve.
This sizing technique was judged to be more representative of the actual depth based on indication voltage.
Appendix 2 provides a listing of the CLT percent through-wall indications reported by bobbin during 2R15 (Low voltage bobbin coil distorted support indications (DSIs) confirmed as CLT with Rotating Coil probe are provided in the table above).
13
Rotating Coil Inspection of the U-bends In response to Series 51 SG operating experience, 100% of the Row 2 thru Row 10 tubes in each steam generator was inspected with a +Point probe in the U-bend (eg:
07H to 07C). Also note that all of row I tubes were preventatively plugged during a previous outage. No degradation was detected in the U-bend region.
Loose Parts During 2R1 5, 100% of the bobbin and Rotating Coil data was reviewed for possible loose part indications. Secondary Side Inspections (SSI) and Foreign Object Search and Retrieval (FOSAR) activities were also performed, as possible. Foreign objects not removed were evaluated to remain in place. Additional +Point inspections were performed in tubes located adjacent to foreign material identified via eddy current exams and/or visual inspections. These supplemental +Point inspections were typically within at least one tube radius of the object. There were no indications of tube wear due to loose parts in any SG, on any tube inspected.
A total of nine tubes were preventative plugged for loose parts (foreign objects) that could not be removed from the Steam Generator. No tube wear was associated with any of these locations. Many tubes were conservatively stabilized within the area of the loose part, even though no tube wear was evident. SG 22, tubes R30 C23 and R31 C24 were preventatively plugged due to one foreign object confirmed by visual inspections. SG 24, tube R7 C51, was preventatively plugged due to a PLP indication at the TSP. Visual inspections were not performed at this location. SG 24, R1 5 C90, R1 6 C90, R1 7 C90, R1 5 C91, R1 6 C91, R1 7 C91, was preventatively plugged due to one foreign object confirmed by visual inspections.
Stabilization Depth via EPRI ETSS SG Tube ID Indication TSP Conservatively 96910.1 Performed 22 R30C23 PLP TSH Yes No Wear Identified 22 R31C24 PLP TSH Yes No Wear Identified 24 R7C51 PLP 01H No No Wear Identified 24 R1 5C90 PLP TSH Yes No Wear Identified 24 R16C90 PTP TSH Yes No Wear Identified 24 R17C90 PTP TSH Yes No Wear Identified 24 R1 5C91 PTP TSH Yes No Wear Identified 24 R16C91 PTP TSH Yes No Wear Identified 24 R17C91 PTP TSH Yes No Wear Identified 14
Data Quality Data quality is an important parameter influencing the overall performance of a steam generator tube examination system as it has an effect on probability of detection and sizing uncertainties. The following list reflects the tubes preventatively plugged for Data Quality Concerns:
SG Tube ID Indication 21 R12C24 Permeability Variation 21 R23C40 Permeability Variation 22 R14C9 Permeability Variation 22 R15C18 Permeability Variation 22 R7C41 Permeability Variation Freespan Indications When reported during the outage inspection, freespan bobbin coil indications (Manufacturing Burnish Mark (MBM) type indications) are compared to the first ISI data (1983) to determine if change has occurred. As documented in the bobbin coil Examination Technique Specification Sheet (ETSS), change is defined as either:
A phase shift of 10 degrees towards the flaw plane or having signal amplitudes inconsistent with that present in 1983 with consideration given to voltage normalization changes or
" If the location has been Rotating Coil inspected (+Point) two times previously and dispositioned as MBM or No Degradation Found (NDF) AND the current outage bobbin signal has not changed by > 5 degrees towards the flaw plane or greater than 0.3 volt since the first outage (2R9 and later) it was Rotating Coil inspected
+Point inspections were performed on all freespan locations during 2R1 5 that were outside the change criterion, and no degradation was found.
15
Tube Support Plate Integrity Inspections Consistent with Westinghouse study SG-96-05-003 "Investigation of Applicability of Eddy Current to the Detection of Potentially Degraded Tube Support Structures" (VTD 327729), bobbin coil probes were used for the initial screening of the support structures for signals that might be indicative of degradation. Signals identified with bobbin probes (called "Possible Support Indication (PSI)") require confirmation ("No Degradation Detected (NDD)" or "Suspect Ligament Crack (SLC)") using a Rotating Coil +Point probe. The repair criterion of ligament cracking is a145 degrees. During outage 2R15 the scope of inspections included:
" +Point inspection of new PSI indications for confirmation and
+Point inspection of previously identified SLC indications to monitor for change.
In addition to the scopes outlined above, all TSP locations inspected with Rotating Coil
(+Pont) during 2R1 5 for other reasons were assessed for evidence of degraded support structures.
Two newly reported possible ligament crack indications were identified during 2R1 5.
Both of these locations had single ligament crack indications as determined with the
+Point probe. One of these SLCs was detected with bobbin. A review of historical data showed that this indication was present in history with no significant change. The second new SLC location was not detected with bobbin, which is not unexpected for single indications with no missing ligament. Based on previously performed SLC assessments that considered both the review of previous inspection data (bobbin and RC) and previously performed visual inspections, no growth or change could be inferred considering analyst variability and the techniques utilized. The table below provides a current summary of support structures with SLC indications:
16
SG Tube ID IND LOCATION SIZING INFORMATION 21 R14C6 SLC 06H SINGLE 21 R42C36 SLC 06H SINGLE 21 R36C40 SLC 06H SINGLE 21 R43C40 SLC 06H SINGLE 21 R45C41 SLC 06H SINGLE 21 R20C53 SLC 05H SINGLE 22 R37C54 SLC 03H SINGLE 22 R41C54 SLC 103H SINGLE 22 R13C92 SLC 07H SINGLE (New) 23 R6C27 SLC 04H 43 DEG 23 R17C27 SLC 04H 58 DEG 23 R14C37 SLC 04H SINGLE 23 R14C38 SLC 04H 35 DEG 23 R9C40 SLC 06C 39 DEG 23 R45C54 SLC 07H SINGLE 23 R46C54 SLC 07H SINGLE 23 SLC 02H 35 DEG 3-*R9C55 SLC 03H 58 DEG 23 R45C55 SLC 07H SINGLE 23 R3C56 SLC 06C 35 DEG 23 R39C56 SLC 01H SINGLE 23 R44C56 SLC 07H SINGLE 23 R14C57 SLC 05C 39 DEG 23 R42C58 SLC 07H SINGLE (New) 23 R42C59 SLC 04H SINGLE 23 R41C68 SLC 07H SINGLE 23R22C75 SLC 01H 39 DEG 23 SLC 07H 54 DEG 23R29C81 SLC 01C 35 DEG 2-3RC SLC 07C 58 DEG 23 R25C87 SLC 07C SINGLE 24 R26C9 SLC 05C SINGLE 24 R23C28 SLC 02H 20 DEG 24 R20C29 SLC 07C SINGLE 24 R41C39 SLC 02C SINGLE 24 R45C41 SLC 07H SINGLE 24 R46C41 SLC 01H SINGLE 24 SLC 07H SINGLE 24 R34C46 SLC 02C SINGLE 24 R46C54 SLC 07H DOUBLE 24 R45C57 SLC 01H 36 DEG "Double" represents a location with two separated single indications.
17
Free Span Ding Inspections According to the based scope inspection plan, Rotating Coil inspections were performed on at least 20% sample of the HL > 2-volt free span Dings to identify potential PWSCC and/or ODSCC. The 20% sample included free span Dings reported from the TSH +0.5 inches to 07H +2.0 inches. One axial ODSCC indications occurred in a 6.83-volt ding approximately 1.55 inches above TSH that coincided with an associated DNI bobbin call of 2.72 volts. This resulted in expanding the H/L free span Dings inspection to inspecting 100% HL Dings -> 5 V in SG 24 between TSH +0.5 inches and 07H +2.0 inches, and 20% of HL Dings > 5V in steam generators 21, 22 and 23 (the 20%
samples also include a minimum of 20% of HL Dings between TSH and 01 H).
Two tubes in 21 SG were also preventatively plugged due to ding signals above the top of the hot leg tubesheet. These tubes had no degradation detected with either the bobbin or the +Point coils. However, it was noted that these two Dings are in the same relative proximity to the HL tubesheet as the ODSCC axial Ding in 24 SG. Therefore, based on this heightened awareness for the potential of ding ODSCC in this region it was conservatively decided to remove these two tubes from service.
SG Tube ID Indication 24 R28C10 Ding associated ODSCC above HL TTS NDD - Preventative for Ding Signal above HL 21 R26C86 TTS (Complex Signal)
NDD-Preventative for Ding Signal above HL 21 R31 C82 TTS (Complex Signal) 18
Appendix I Anti-Vibration Bar Wear Percent Through-Wall Indications SG Row Col
%TW SupI Inch1 SG21 16 24 7
AV1
-0.09 SG21 16 66 11 AVl
-0.34 SG21 16 66 12 AV4
-0.96 SG21 17 25 13 AV3 0.02 SG21 17 35 8
AVl 0.15 SG21 17 37 12 AV4
-0.37 SG21 17 39 15 AVl
-0.2 SG21 17 39 13 AV2 0.09 SG21 17 39 13 AV3
-0.07 SG21 17 52 13 AVl
-2.23 SG21 17 52 14 AVI 2.33 SG21 17 52 11 AV2
-0.87 SG21 17 52 10 AV2 1.11 SG21 17 52 9
AV3
-0.93 SG21 17 52 14 AV3 1.09 SG21 17 52 13 AV4
-0.33 SG21 17 56 17 AV2 0.09 SG21 17 56 10 AV3 0.24 SG21 17 63 14 AV2 0.11 SG21 17 63 12 AV3
-0.16 SG21 17 63 9
AV3 0.06 SG21 18 34 11 AV2 0.02 SG21 18 67 9
AVl
-0.92 SG21 18 67 5
AV4 0.67 SG21 19 58 26 AV2 0.55 SG21 19 58 16 AV4 0.31 SG21 19 66 12 AVl
-0.53 SG21 19 66 22 AV2 0.15 SG21 19 66 25 AV3 0.19 SG21 19 66 6
AV4
-1.02 SG21 21 29 8
AV3 0.17 SG21 21 29 16 AV4
-0.56 SG21 21 60 12 AV2
-0.3 SG21 21 60 15 AV3
-0.36 SG21 22 60 15 AV2
-0.26 SG21 23 64 20 AV2 0.09 SG21 23 64 22 AV3 0.19 SG21 23 67 23 AVi
-0.94 SG21 23 67 29 AV2
-0.35 19
SG Row Col
%TW Supp Inch1 SG21 23 67 26 AV3
-0.13 SG21 23 70 14 AV4 1.64 SG21 24 41 8
AV1
-1 SG21 24 52 10 AVI
-1.92 SG21 24 52 18 AV2 1.13 SG21 24 52 8
AV3 1.15 SG21 24 52 14 AV4 0.9 SG21 24 67 15 AV2
-0.28 SG21 24 68 22 AV2 0.51 SG21 24 68 24 AV3 0.04 SG21 24 70 8
AV1 0.6 SG21 25 24 9
AV3 0.02 SG21 26 46 12 AV2 0.3 SG21 26 56 25 AV1 0.32 SG21 26 56 26 AV2 0.11 SG21 26 56 29 AV3 0.13 SG21 26 56 32 AV4
-0.73 SG21 26 58 12 AV2
-0.53 SG21 26 58 19 AV3
-0.71 SG21 26 59 12 AV2 0.11 SG21 26 59 15 AV3 0.3 SG21 26 59 10 AV4
-0.43 SG21 26 63 12 AV4
-0.62 SG21 26 64 19 AV1
-0.06 SG21 26 64 10 AV2 0.19 SG21 26 64 10 AV3 0.19 SG21 26 67 22 AV1
-0.49 SG21 26 67 9
AV2
-0.28 SG21 27 44 14 AV1
-0.47 SG21 27 44 31 AV2
-0.04 SG21 27 44 34 AV3 0.26 SG21 27 44 27 AV4 0.57 SG21 27 45 18 AV4 0.35 SG21 27 46 15 AV2
-0.37 SG21 27 46 32 AV2 0.2 SG21 27 46 36 AV3 0.2 SG21 27 46 25 AV4
-0.39 SG21 27 50 10 AV2
-0.81 SG21 27 50 19 AV3
-0.86 SG21 27 50 8
AV4
-0.64 SG21 27 56 21 AVl 0.34 SG21 27 56 34 AV2 0.11 SG21 27 56 35 AV3 0.06 SG21 27 56 23 AV4
-0.53 20
SG Row Col
%TW SuDp Inch1 SG21 27 56 10 AV4 0.48 SG21 27 59 22 AV4
-0.45 SG21 27 64 22 AVM
-0.21 SG21 27 64 26 AV2 0.28 SG21 27 64 40 AV3 0.19 SG21 29 46 20 AVi
-0.55 SG21 29 46 34 AV2 0.04 SG21 29 46 39 AV3 0.02 SG21 29 46 13 AV4
-0.17 SG21 29 57 22 AV2 0.3 SG21 29 57 24 AV3
-0.23 SG21 29 57 21 AV4
-0.11 SG21 29 65 12 AV3 0.43 SG21 29 65 27 AV4
-0.43 SG21 31 64 28 AV2
-0.13 SG21 31 67 15 AV2 0.36 SG21 32 39 10 AV4 0.06 SG21 32 48 25 AV2
-0.11 SG21 32 48 30 AV3 0.22 SG21 32 49 12 AV3 1.24 SG21 32 49 12 AV4
-0.7 SG21 32 51 12 AV2 1.07 SG21 32 51 27 AV3
-1.35 SG21 32 51 28 AV3 1.15 SG21 32 51 20 AV4 1.54 SG21 32 54 10 AV3
-0.24 SG21 33 41 8
AV2
-0.04 SG21 33 41 7
AV3
-0.2 SG21 33 41 12 AV4 0.67 SG21 33 55 14 AV3 0.01 SG21 33 60 25 AVM 0.23 SG21 33 60 27 AV3 0.4 SG21 34 36 9
AVM
-0.31 SG21 34 36 11 AV1 0.34 SG21 34 36 27 AV2
-0.36 SG21 34 36 14 AV3
-0.28 SG21 34 37 9
AV1 0.49 SG21 34 37 23 AV2 0.36 SG21 34 37 19 AV3 0.23 SG21 34 37 9
AV4 0.06 SG21 34 44 10 AVM 0.32 SG21 34 44 24 AV2
-0.06 SG21 34 44 35 AV3 0.13 SG21 34 44 10 AV4 0.58 21
SG Row Col
%TW Supp Inch1 SG21 34 45 9
AV1 0.11 SG21 34 45 15 AV2
-0.09 SG21 34 45 26 AV3
-0.48 SG21 34 45 18 AV4
-0.26 SG21 34 49 10 AV2 1.15 SG21 34 49 11 AV3 1.17 SG21 34 51 24 AVW
-0.13 SG21 34 51 23 AV2 1.27 SG21 34 51 23 AV3 1.14 SG21 34 52 14 AV2 0.86 SG21 34 65 29 AV3
-0.45 SG21 34 65 25 AV4
-0.32 SG21 35 53 9
AV4 0.07 SG21 35 63 10 AV1
-0.6 SG21 35 63 15 AV2 0.17 SG21 35 68 15 AVW
-0.47 SG21 35 68 15 AV2
-0.25 SG21 35 68 9
AV3 0.01 SG21 36 41 21 AV3 0.13 SG21 36 43 16 AV3
-0.35 SG21 36 43 9
AV4 0.2 SG21 36 50 9
AV2 0.83 SG21 36 53 9
AV1
-0.52 SG21 36 53 10 AV2 0.62 SG21 36 56 24 AV2 0.01 SG21 36 58 21 AVI 0.36 SG21 36 58 33 AV2
-0.51 SG21 36 58 12 AV2 0.46 SG21 36 58 30 AV3
-0.46 SG21 39 37 9
AVI
-0.15 SG21 39 37 15 AV1 0.28 SG21 39 37 24 AV2 0.02 SG21 39 54 10 AVI
-0.21 SG21 39 61 23 AVl
-0.49 SG21 39 61 28 AV2
-0.49 SG21 40 58 15 AV2
-0.43 SG21 41 50 10 AVW 0.09 SG21 41 53 10 AVI 0.43 SG21 41 53 16 AV2
-0.24 SG21 41 58 10 AV1 0.13 SG21 41 58 8
AV4 0,02 SG21 42 31 10 AV3
-0.02 SG21 42 34 6
AV4
-0.19 SG22 16 68 16 AV2
-0.32 22
SG Row Col
%TW Su~p Inch1 SG22 16 68 13 AV3 0.25 SG22 16 68 13 AV4 0.72 SG22 18 65 25 AVI
-1.53 SG22 18 65 13 AVW 1.4 SG22 18 65 20 AV2
-0.58 SG22 18 65 22 AV2 0.84 SG22 18 65 29 AV3 0.02 SG22 18 65 18 AV4
-0.75 SG22 18 65 11 AV4 0.85 SG22 22 62 11 AV2
-0.19 SG22 22 62 25 AV3
-0.23 SG22 23 71 17 AV1
-1.71 SG22 23 71 10 AV2 0.02 SG22 23 71 19 AV3 0.22 SG22 23 71 13 AV4 0.18 SG22 23 74 13 AV2
-0.21 SG22 23 74 12 AV4
-0.45 SG22 25 9
12 AV2 0.43 SG22 25 9
19 AV3 0.04 SG22 25 30 18 AVl 1.88 SG22 25 30 25 AV2 0.06 SG22 25 30 35 AV3 0.19 SG22 25 55 12 AVl 1.03 SG22 25 63 12 AV3
-0.47 SG22 25 69 16 AV2
-0.39 SG22 25 69 22 AV2 0.32 SG22 25 69 31 AV3 0.39 SG22 25 71 18 AV3 0.3 SG22 26 23 18 AV3
-0.09 SG22 26 62 28 AVI 0.52 SG22 26 62 27 AV2 0.06 SG22 26 62 25 AV3
-0.22 SG22 26 62 11 AV4 0.31 SG22 27 28 18 AV2
-0.43 SG22 27 28 16 AV3 0.13 SG22 31 27 21 AV2
-0.06 SG22 31 28 15 AVI 0.53 SG22 31 28 26 AV2 0.38 SG22 32 52 12 AV2
-0.17 SG22 32 52 14 AV3
-0.19 SG22 33 67 12 AV2
-0.22 SG22 33 67 16 AV2 0.39 SG22 34 32 33 AVI 0.09 SG22 34 32 36 AV2 0.38 23
SG Row Col
%TW SuDD Inch1 SG22 34 32 29 AV3 0.02 SG22 34 39 14 AV3
-0.04 SG22 34 41 10 AV3 0.06 SG22 34 46 14 AV3
-0.04 SG22 34 47 14 AV3
-0.08 SG22 34 49 40 AV4
-0.59 SG22 34 50 10 AVI 0.86 SG22 34 50 16 AV2
-0.24 SG22 34 50 29 AV3 0.28 SG22 34 50 20 AV4 0.87 SG22 34 58 19 AV2 0.02 SG22 34 70 14 AV4
-0.19 SG22 35 26 11 AVl 0.11 SG22 35 26 11 AV2 0.11 SG22 35 53 16 AV2 0.02 SG22 35 53 12 AV3
-0.28 SG22 36 34 29 AV3 0.11 SG22 36 51 15 AV2 0.04 SG22 40 36 30 AV4
-0.21 SG22 40 37 17 AVI 1.2 SG22 40 37 22 AV2 0.04 SG22 40 44 22 AV1 0.4 SG22 40 44 32 AV2 0.05 SG22 41 32 12 AV3
-0.04 SG23 15 77 11 AV2 0.64 SG23 15 77 10 AV4
-1.48 SG23 16 57 19 AV1 0.64 SG23 16 57 12 AV2
-0.21 SG23 16 57 20 AV3
-0.34 SG23 16 57 15 AV4
-1.02 SG23 20 31 11 AV1 1.24 SG23 20 56 8
AV4
-1.62 SG23 20 58 8
AVW 0.02 SG23 20 64 10 AV4 0.02 SG23 20 67 13 AVW
-0.88 SG23 20 67 9
AV2
-0.13 SG23 21 22 12 AV2 0.17 SG23 21 32 10 AVI
-0.13 SG23 21 44 11 AVW 0.66 SG23 21 44 13 AV2 0.02 SG23 23 40 13 AV3 0.21 SG23 23 44 8
AV2 0.11 SG23 23 49 6
AVI
-0.63 SG23 23 53 9
AV1 0.77 24
SG Row Col
%TW Supp Inchi SG23 23 53 14 AV2
-0.15 SG23 23 53 9
AV2 0.43 SG23 23 53 26 AV3
-0.09 SG23 23 53 8
AV4
-0.21 SG23 23 58 12 AVI
-0.22 SG23 23 58 26 AV2
-0.26 SG23 23 58 16 AV2 0.23 SG23 23 58 38 AV3 0.06 SG23 23 58 14 AV4 0.51 SG23 24 46 11 AV3 0.45 SG23 24 48 11 AV1
-0.07 SG23 24 48 13 AV2
-0.13 SG23 24 53 7
AV3 0.04 SG23 24 55 7
AV1
-1.1 SG23 24 55 16 AV1 1.28 SG23 24 55 8
AV4
-3.03 SG23 24 56 21 AVl
-0.66 SG23 24 56 18 AV2
-0.87 SG23 24 56 18 AV2 1.11 SG23 24 56 21 AV3
-0.83 SG23 24 56 27 AV3 0.87 SG23 24 56 15 AV4
-1.61 SG23 24 56 5
AV4 1.47 SG23 24 60 8
AV2 0.06 SG23 25 44 9
AV2 0.11 SG23 25 57 11 AVI 0.49 SG23 25 57 10 AV2
-0.19 SG23 26 44 9
AV1
-0.57 SG23 26 44 13 AVl 0.6 SG23 26 44 30 AV2 0.02 SG23 26 44 28 AV3 0.02 SG23 26 44 17 AV4
-0.09 SG23 26 45 30 AVI
-0.07 SG23 26 45 28 AV2
-0.02 SG23 26 45 13 AV4 0.66 SG23 26 55 23 AV1
-0.82 SG23 26 55 31 AV2 0.32 SG23 26 55 13 AV3 0.11 SG23 26 63 9
AVI
-1.02 SG23 26 63 9
AV2
-0.15 SG23 27 49 9
AV1 0.82 SG23 27 49 12 AV2
-0.41 SG23 27 49 12 AV3 0.09 SG23 27 51 23 AVI
-1.04 25
SG Row Col
%TW Supp Inchl SG23 27 51 43 AV2 0.11 SG23 27 51 34 AV3 0.04 SG23 27 51 34 AV4
-0.36 SG23 27 59 31 AVW 0.42 SG23 27 59 19 AV2 0.53 SG23 27 59 13 AV3 0.27 SG23 27 59 12 AV4 0.37 SG23 27 63 30 AVW 1.41 SG23 27 63 39 AV2 0.17 SG23 27 63 29 AV3 0.28 SG23 27 63 23 AV4
-0.89 SG23 27 64 11 AVW
-0.84 SG23 27 64 8
AV2 0.08 SG23 27 65 16 AV2 0.02 SG23 27 65 17 AV3
-0.23 SG23 27 65 12 AV3 0.3 SG23 27 65 16 AV4 1.21 SG23 28 45 19 AV2
-0.02 SG23 30 25 10 AV4
-0.09 SG23 30 27 8
AV3
-0.12 SG23 30 27 11 AV4 0.07 SG23 30 35 41 AV2
-0.04 SG23 30 35 21 AV3
-0.37 SG23 30 35 26 AV4 0.86 SG23 30 57 11 AVW 0.04 SG23 30 57 10 AV2
-0.25 SG23 30 64 10 AV4
-0.15 SG23 31 63 13 AV2
-0.04 SG23 32 41 16 AV2 0.09 SG23 32 41 37 AV3
-0.24 SG23 32 45 36 AVI
-0.09 SG23 32 45 42 AV2
-0.02 SG23 32 45 43 AV3 0.02 SG23 32 45 15 AV4
-0.56 SG23 32 45 35 AV4 0.56 SG23 32 59 24 AV3 0.17 SG23 32 59 13 AV4 0.39 SG23 32 61 13 AVW 0.38 SG23 32 61 27 AV3
-0.25 SG23 33 26 9
AVW 0.07 SG23 33 26 15 AV2
-0.02 SG23 33 26 19 AV3
-0.5 SG23 33 50 8
AV1 0.13 SG23 33 51 6
AV2 0.06 26
SG Row Col
%TW Supp Inchi SG23 33 51 5
AV3
-0.08 SG23 33 52 10 AV1 0.08 SG23 34 38 12 AV3
-0.04 SG23 34 38 9
AV4
-0.04 SG23 34 41 11 AV3
-0.19 SG23 34 52 13 AV4 0.02 SG23 34 54 10 AV4 1.94 SG23 35 53 14 AV3
-0.08 SG23 35 53 16 AV4 0.02 SG23 35 54 11 AV4 1.37 SG23 36 44 11 AV3
-0.02 SG23 36 44 24 AV4
-0.02 SG23 36 45 15 AV3 0.11 SG23 36 45 16 AV4
-0.41 SG23 36 45 12 AV4 0.51 SG23 36 58 24 AV4 0.07 SG23 36 63 14 AVl
-0.68 SG23 36 63 10 AVI 0.76 SG23 36 63 21 AV2 0.02 SG23 36 66 9
AV4
-0.74 SG23 36 71 8
AV2 0.15 SG23 37 42 15 AV3 0.26 SG23 37 42 19 AV4
-0.41 SG23 37 45 16 AV3 0.11 SG23 37 45 25 AV4
-0.32 SG23 37 52 32 AV4 0.02 SG23 38 41 10 AV2 0.04 SG23 38 44 8
AV2 0.04 SG23 38 46 11 AV3 0.32 SG23 38 46 15 AV4
-0.15 SG23 38 47 23 AV3 0.02 SG23 38 47 20 AV4
-0.02 SG23 38 48 33 AV3
-0.51 SG23 39 50 12 AVI
-0.02 SG23 39 50 21 AV2 0.34 SG23 39 51 19 AV1 0.47 SG23 39 51 10 AV3 0.01 SG23 39 52 23 AVi 0.08 SG23 39 52 23 AV2 0.02 SG23 39 58 22 AV1 0.04 SG23 39 58 32 AV2 0.23 SG23 39 60 12 AV3 0.1 SG23 39 60 15 AV4
-0.42 SG23 39 60 10 AV4 0.17 27
SG Row Col
%TW Supp Inchl SG23 40 42 14 AVM 0.09 SG23 40 42 38 AV2 0.32 SG23 40 43 9
AV2
-0.19 SG23 40 43 17 AV3 0.04 SG23 40 50 28 AV2 0.15 SG23 40 50 11 AV3 0.02 SG23 40 50 3
AV4
-0.06 SG23 40 51 21 AVM
-0.25 SG23 40 51 32 AV2 0.1 SG23 40 51 14 AV3 0.02 SG23 40 56 10 AVM
-0.28 SG23 40 56 8
AVM 0.35 SG23 40 62 11 AVM 0.13 SG23 40 66 21 AV2 0.08 SG23 41 29 8
AV3
-0.13 SG23 41 52 13 AV2 0.02 SG23 41 52 20 AV3
-0.19 SG23 41 55 36 AVI
-0.67 SG23 41 55 15 AVM 0.51 SG23 41 55 10 AV2
-0.38 SG23 41 55 32 AV2 0.06 SG23 41 60 12 AV2 0.06 SG23 41 61 14 AVM 0.02 SG23 41 63 10 AV3 0.04 SG23 41 65 14 AV2 0.1 SG23 42 52 11 AVM 0.08 SG23 42 60 9
AV3
-0.04 SG23 42 65 26 AV2 0.06 SG23 42 66 7
AV2 0.17 SG23 42 66 9
AV3
-0.02 SG23 42 67 31 AVM 0.04 SG23 42 67 27 AV2 0.11 SG23 42 67 36 AV3
-0.08 SG23 43 34 11 AV4 0.01 SG23 43 63 18 AV2 0.02 SG23 44 40 12 AV4
-0.06 SG23 45 58 8
AVl
-0.08 SG23 45 58 9
AV3 0.02 SG23 45 58 17 AV4
-0.13 SG24 15 33 10 AVl 0.22 SG24 15 33 10 AV3
-0.26 SG24 17 32 8
AV2 0.35 SG24 17 32 17 AV3
-0.37 SG24 17 32 11 AV4
-0.72 28
SG Row Col
%TW SuM InchI SG24 17 65 23 AV2
-0.11 SG24 17 65 10 AV3
-0.3 SG24 17 65 16 AV3 0.31 SG24 17 65 18 AV4
-1.51 SG24 17 78 14 AV2 0.11 SG24 18 23 20 AV4
-0.31 SG24 18 55 14 AVI 0.09 SG24 18 55 17 AV2 0.11 SG24 18 55 14 AV3 0.09 SG24 18 55 15 AV4 0.43 SG24 20 6
8 AV2
-0.04 SG24 21 28 13 AV1
-0.61 SG24 21 28 21 AV2 0.04 SG24 21 28 27 AV3
-0.22 SG24 21 28 14 AV4 0.64 SG24 21 30 13 AV1
-0.22 SG24 21 30 17 AV2
-0.26 SG24 21 30 17 AV2 0.33 SG24 21 30 9
AV3
-0.74 SG24 21 30 13 AV3 0.72 SG24 21 72 21 AV4
-0.15 SG24 22 72 30 AV2 0.02 SG24 23 28 37 AV3 0.2 SG24 23 28 13 AV4 0.57 SG24 23 33 13 AV1
-0.2 SG24 23 33 27 AV2
-0.33 SG24 23 33 13 AV2 0.24 SG24 23 33 21 AV3 0.2 SG24 23 33 14 AV4
-0.37 SG24 23 33 7
AV4 0.18 SG24 23 53 20 AV4
-0.07 SG24 23 56 10 AV3 0.51 SG24 23 56 19 AV4 0.16 SG24 23 57 11 AVI 0.39 SG24 23 57 14 AV2
-0.44 SG24 23 57 13 AV2 0.31 SG24 23 57 32 AV3
-0.04 SG24 23 57 34 AV4
-0.09 SG24 23 59 22 AVI 1.25 SG24 23 59 26 AV2 0.39 SG24 23 59 16 AV3
-0.37 SG24 23 59 17 AV3 0.27 SG24 23 62 12 AVI 0.99 SG24 23 62 22 AV2
-0.73 29
SG Row Col
%TW Supp Inchi SG24 23 62 29 AV3
-0.18 SG24 23 62 18 AV4 0.72 SG24 23 72 14 AV2 0.4 SG24 23 72 29 AV4
-0.73 SG24 24 34 23 AV2
-0.07 SG24 24 34 21 AV3 0.07 SG24 24 34 17 AV4
-0.76 SG24 24 35 17 AVI 0.31 SG24 24 35 13 AV2 0.18 SG24 24 35 20 AV3 0.2 SG24 25 72 18 AV2 0.02 SG24 26 34 25 AVi 0.26 SG24 26 34 33 AV2
-0.09 SG24 26 34 23 AV3 0.06 SG24 26 34 17 AV4 0.58 SG24 26 58 17 AVI
-0.28 SG24 26 58 28 AV2 0.11 SG24 26 58 29 AV3 0.28 SG24 26 58 16 AV4 1.3 SG24 26 62 18 AV4 0.5 SG24 26 67 14 AV1 0.11 SG24 26 67 17 AV2 0.22 SG24 27 62 12 AVl 0.72 SG24 27 62 14 AV2
-0.77 SG24 27 68 31 AV3
-0.13 SG24 27 68 26 AV4
-0.11 SG24 28 59 15 AV1 0.24 SG24 28 59 23 AV2 0.15 SG24 31 31 40 AV3
-0.02 SG24 31 48 9
AV3 0.06 SG24 32 64 16 AV2
-0.11 SG24 33 29 13 AV1 0.21 SG24 33 29 15 AV2 0.13 SG24 33 36 11 AVI
-0.78 SG24 33 41 17 AVI
-0.37 SG24 33 48 10 AV1
-0.77 SG24 33 48 9
AV1 0.02 SG24 33 48 13 AV2 0.04 SG24 33 50 10 AV3 0.09 SG24 33 50 11 AV4 0.09 SG24 33 51 7
AVl
-0.78 SG24 33 51 34 AV2
-0.67 SG24 33 51 9
AV3
-0.84 SG24 33 57 14 AV1 0.02 30
SG Row Col
%TW Supp Inch1 SG24 33 57 12 AV2
-0.37 SG24 33 57 21 AV3 0.56 SG24 33 57 28 AV4
-0.09 SG24 33 58 23 AV3
-0.26 SG24 33 58 8
AV4
-0.09 SG24 33 65 12 AV3
-0.24 SG24 33 66 30 AV2
-0.11 SG24 33 66 10 AV3
-0.18 SG24 33 67 24 AVI 0.04 SG24 34 63 30 AV2
-0.06 SG24 34 63 31 AV3 0.02 SG24 34 63 15 AV4 0.37 SG24 34 65 31 AV3
-0.4 SG24 34 65 24 AV4 0.29 SG24 36 63 16 AV3
-0.09 SG24 38 39 13 AV3
-0.21 SG24 38 39 18 AV4
-0.28 SG24 38 52 15 AV3
-0.37 SG24 38 52 29 AV4 0.39 SG24 38 67 27 AV2 0.02 SG24 38 67 36 AV3
-0.17 SG24 38 68 31 AV2 0.24 SG24 38 68 39 AV3
-0.09 SG24 38 68 39 AV4
-0.09 SG24 39 42 14 AV3 0.09 SG24 39 42 13 AV4 0.51 SG24 39 49 9
AV3 0.15 SG24 39 49 33 AV4
-0.21 SG24 39 65 32 AVI
-0.07 SG24 39 65 20 AV2 0.02 SG24 40 37 29 AV1 0.06 SG24 40 37 23 AV2
-0.06 SG24 40 55 10 AVl
-0.13 SG24 40 56 23 AVI 0.09 SG24 40 56 17 AV2
-0.15 SG24 40 57 10 AV4 0.11 SG24 41 35 19 AV1
-0.02 SG24 41 35 20 AV2
-0.13 SG24 41 53 14 AVI
-0.19 SG24 41 53 33 AV2
-0.19 SG24 41 53 30 AV3
-0.34 SG24 41 53 20 AV3 0.24 SG24 41 53 25 AV4 0.02 SG24 41 57 7
AV1 0.02 31
SG Row Col
%TW SupD Inch1 SG24 41 59 19 AV4 0.11 SG24 42 53 10 AV1 0.02 SG24 42 53 12 AV2 0.06 SG24 42 55 40 AV1
-0.19 SG24 42 55 17 AV2 0.02 SG24 44 35 28 AV1 0.11 SG24 44 35 11 AV2 0.04 SG24 44 35 8
AV3
-0.04 SG24 44 55 7
AV4 0.17 SG24 45 54 17 AVM 0.23 32
Appendix 2 Cold Leg Thinning Percent Through-Wall Indications SG Row Col SG Row Col
%TW Sum Inch1 Volts 26 01C
-0.04 1.11 SG21 34 79 SG21 35 76 22 02C
-0.04 0.7 SG21 44 59 12 03C
-0.28 0.46 SG21 45 57 14 03C
-0.23 0.41 SG21 45 58 28 04C
-0.27 0.48 SG21 46 48 1
01C 0.41 0.22 SG22 3
1 33 01C 0.19 0.35 SG22 6
2 26 01C 0.04 1.81 SG22 22 87 1
01C 0.17 0.28 SG22 32 78 58 02C 0.02 3.75 SG22 32 79 17 02C
-0.02 0.49 SG22 32 79 5
03C
-0.09 0.99 SG22 33 17 20 01C 0.42 0.45 SG22 33 76 1
01C
-0.17 0.54 SG22 34 17 25 01C 0.36 0.93 SG22 34 18 1
03C
-0.25 0.6 SG22 36 18 23 02C
-0.15 1.18 SG22 36 18 21 01C
-0.06 2.1 SG22 37 19 31 01C
-0.02 0.89 SG22 37 68 6
02C
-0.04 0.27 SG22 40 67 1
02C 0.19 0.64 SG22 40 69 23 01C
-0.06 0.23 SG22 41 62 26 02C 0.13 0.92 SG22 41 67 1
02C
-0.09 0.84 SG22 42 41 33 02C 0.08 0.97 SG22 42 61 26 02C 0
0.64 SG22 42 62 30 02C
-0.02 0.5 SG22 42 63 1
02C 0
0.58 SG22 42 65 21 01C 0.39 0.5 SG22 42 67 1
01C 0.23 0.48 SG22 43 37 12 02C
-0.09 0.25 SG22 43 53 21 02C 0.26 0.27 SG22 43 58 15 02C 0.04 0.21 SG22 43 61 1
02C
-0.09 0.48 SG22 43 64 19 02C 0.04 0.96 SG22 43 64 1
01C 0.38 0.33 SG22 43 65 30 02C 0.11 1.35 SG22 44 37 5
02C
-0.11 0.57 SG22 44 38 13 01C 0.06 0.66 33
SG SG22 Row 44 Col 39
%TW 25 02C Inch1
-0.06 Volts 0.45 SG22 44 39 19 01C 0.23 0.51 SG22 44 46 9
02C 0.19 0.54 SG22 44 47 1
02C 0.19 0.63 SG22 44 56 8
02C 0.15 1.41 SG22 44 58 4
02C
-0.11 0.49 SG22 44 59 1
02C
-0.06 0.41 SG22 44 60 1
02C 0.08 0.61 SG22 44 61 1
04C 0.21 0.29 SG22 44 62 1
03C
-0.17 0.54 SG22 45 41 8
02C 0.17 0.82 SG22 45 45 4
02C 0.11 0.49 SG22 45 47 1
02C 0.21 0.6 SG22 45 48 26 03C
-0.06 0.22 SG22 45 48 15 01C
-0.02 0.29 SG22 45 50 22 02C 0.26 0.89 SG22 45 52 1
02C 0.22 0.43 SG22 45 55 1
02C 0.17 0.46 SG22 45 56 1
02C 0.19 0.52 SG22 45 58 1
01C 0.21 0.44 SG22 46 41 11 02C
-0.13 0.51 SG22 46 47 18 02C 0.06 0.82 SG22 46 51 1
02C 0.13 0.41 SG22 46 52 24 02C 0.28 0.36 SG22 46 54 1
01C 0.23 0.35 SG23 2
1 12 02C
-0.24 0.37 SG23 3
1 26 01C
-0.02 0.84 SG23 6
3 2
01C 0.23 0.64 SG23 8
3 22 01C 0.06 0.9 SG23 9
2 5
0IC 0.21 0.36 SG23 11 2
24 01C
-0.02 0.22 SG23 11 3
64 01C 0
0.95 SG23 12 4
32 oiC
-0.06 0.71 SG23 14 5
12 oiC
-0.08 0.22 SG23 23 8
1 01C
-0.15 0.44 SG23 25 9
18 01C 0.21 0.85 SG23 27 10 20 oiC 0.19 0.37 SG23 30 12 1
01C
-0.21 0.5 SG23 30 14 10 02C
-0.26 0.26 SG23 31 14 35 01C 0.02 0.64 SG23 33 18 13 01C
-0.02 0.44 SG23 34 17 36 01C 0
3.02 SG23 34 18 27 01C 0.04 2.15 SG23 37 19 30 02C
-0.11 1.14 34
SG SG23 Row 40 Col 33
%TW 29 SU02 02C Inch1
-0.3 Volts 0.3 SG23 44
{34 2
OIC
-0.13 0.59 SG23 44 36 12 01C
-0.17 2.36 SG24 2
94 1
01C 0.17 0.76 SG24 11 3
28 01C
-0.04 1.54 SG24 25 87 1
01C 0
0.28 SG24 27 83 1
01C
-0.11 0.79 SG24 28 83 29 01C
-0.06 1.35 SG24 28 85 1
01C 0.31 0.68 SG24 29 82 44 01C 0
12.06 SG24 30 82 10 01C
-0.11 0.79 SG24 31 79 1
02C 0.17 0.75 SG24 31 82 15 01C 0.04 0.25 SG24 36 75 1
02C 0.19 0.5 SG24 36 76 7
01C 0.09 0.55 SG24 36 76 1
02C 0.11 0.58 SG24 37 73 5
01C
-0.17 0.43 SG24 37 75 1
01C
-0.11 0.78 SG24 38 23 28 02C 0
0.24 SG24 38 73 15 01C
-0.06 1.14 SG24 39 23 1
02C
-0.11 1.27 SG24 39 71 5
01C
-0.2 0.61 SG24 41 59 24 01C
-0.02 0.35 SG24 42 59 10 02C 0
0.39 SG24 43 33 30 02C
-0.02 0.32 SG24 43 58 9
02C 0.3 1.14 SG24 43 62 4
02C 0.21 2.32 SG24 43 62 1
01C 0.15 0.97 SG24 43 64 25 02C 0.15 0.96 SG24 44 36 11 03C 0.04 0.6 SG24 44 58 26 01C
-0.04 0.98 SG24 44 58 1
02C
-0.27 0.78 SG24 44 59 22 01C
-0.11 1.45 SG24 44 59 5
02C 0.19 1.24 SG24 44 60 1
01C 0.11 0.51 SG24 44 62 5
02C 0.09 1.44 SG24 45 37 1
02C 0.02 0.69 SG24 45 48 20 02C 0.04 0.66 SG24 45 51 5
02C 0.06 0.32 SG24 45 57 1
01C
-0.17 0.56 SG24 45 59 1
02C
-0.28 0.6 35