1CAN101306, Unit 1, Steam Generator Tube Inspection Report - 1R24

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Unit 1, Steam Generator Tube Inspection Report - 1R24
ML13296A746
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 10/23/2013
From: Pyle S
Entergy Operations
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
1CAN101306
Download: ML13296A746 (20)
v • d • e


Text

Entergy Operations, Inc.

1448 S.R. 333 Russellville, AR 72802 Tel 479-858-4704 Stephenie L. Pyle Manager, Licensing Arkansas Nuclear One 1CAN101306 October 23, 2013 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

Subject:

Steam Generator Tube Inspection Report - 1R24 Arkansas Nuclear One - Unit 1 Docket No. 50-313 License No. DPR-51

Dear Sir or Madam:

Entergy Operations, Inc. (Entergy) inspected the Arkansas Nuclear One, Unit 1 (ANO-1) steam generator (SG) tubes during the Spring 2013 refueling outage (1R24) in accordance with ANO-1 Technical Specification (TS) 5.5.9, Steam Generator (SG) Program. ANO-1 TS 5.6.7 requires that the results of inspections performed during the report period be submitted to the NRC within 180 days after the initial entry into Mode 4. The initial entry into Mode 4 post-1R24 was made on August 2, 2013. Enclosed is the subject inspection report.

The 1R24 inspection performed on both SGs involved an initial full-length bobbin coil examination of specific locations near tie rods. The X-probe used consists of an array of coils for diagnostic testing.

This submittal completes the reporting requirements of the ANO-1 TSs for this inspection.

This submittal contains no regulatory commitments. Should you have any questions, please contact me.

Sincerely, Original signed by Stephenie L. Pyle SLP/rwc

Enclosure:

Results of ANO-1 Steam Generator (SG) Tube Inspections During 1R24

1CAN101306 Page 2 of 2 cc: Mr. Steven A. Reynolds Regional Administrator U. S. Nuclear Regulatory Commission Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 NRC Senior Resident Inspector Arkansas Nuclear One P. O. Box 310 London, AR 72847 U. S. Nuclear Regulatory Commission Attn: Mr. Kaly Kalyanam MS O-8B1 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Mr. Bernard R. Bevill Arkansas Department of Health Radiation Control Section 4815 West Markham Street Slot #30 Little Rock, AR 72205

ENCLOSURE TO 1CAN101306 Results of ANO-1 Steam Generator (SG) Tube Inspections During 1R24

Enclosure to 1CAN101306 Page 1 of 17 RESULTS OF ANO-1 STEAM GENERATOR (SG) TUBE INSPECTIONS DURING 1R24 1 INTRODUCTION Arkansas Nuclear One, Unit 1 (ANO-1) Technical Specification (TS) 5.6.7, Steam Generator Tube Inspection Reports, requires Entergy Operations, Inc. (Entergy) to submit a 180-day report to the NRC that outlines the details of the SG tubing inspections that were performed during the reporting period. The report shall include:

1. The scope of inspections performed on each SG.
2. Active degradation mechanisms found.
3. Nondestructive examination (NDE) techniques utilized for each degradation mechanism.
4. Location, orientation (if linear), and measured sizes (if available) of service-induced indications.
5. Number of tubes plugged during the inspection outage for each active degradation mechanism.
6. Total number and percentage of tubes plugged to date.
7. The results of condition monitoring, including the results of tube pulls and in-situ testing.

The operating period for this report includes one refueling inspection outage (1R24), in March-May 2013. This inspection was not an American Society of Mechanical Engineers (ASME)

Code In-Service Inspection (ISI). This report details the result of that inspection. The inspection was to determine the extent of bowing of the tie rods and not an ASME Code type inspection. Tube Support Plate (TSP) wear was justified for two cycles. The extent of bowing was consistent with predictions made in the previous operational assessment (OA). Also the tubes that contained wear were consistent with the growth rates and estimates predicted in the previous OA. The degradation identified met all performance criteria.

1R24 examinations were established to validate the growth rate for the tube-to-tube wear (TTW). The TTW growth rates were consistent with the previous Condition Monitoring and Operational Assessment (CMOA) (1R23).

2 DESIGN The replacement SGs for ANO-1 are Enhanced Once-Through Steam Generators (EOTSGs) manufactured by AREVA. The EOTSG is a straight shell-and-tube type heat exchanger installed in a vertical position with bottom supports and emergency supports as required to accommodate normal and accident loads. The tubing consists of Inconel 690 thermally-treated tubing that is 5/8" in diameter with a 0.037" wall thickness. The tubes are expanded full depth hydraulically in the tubesheet. There are 15 TSPs that are constructed of stainless steel (SA 240 Type 410) and are a broached trefoil-hole design.

Enclosure to 1CAN101306 Page 2 of 17 3 Report Requirements 3.1 The scope of inspections performed on each SG.

Table 3.1.1 1R24 Inspection Scope Examination Type Inspections Conducted  % Scope Extent Tested SG A X-Probe (bobbin) 454 UTE to 09S X-Probe/Plus Point 502 UTE to LTE SG B X-Probe (bobbin) 446 UTE to 09S X-Probe/Plus Point 467 UTE to LTE Plus Point 23 Varies Note: UTE Upper Tube End LTE Lower Tube End X-Probe full length scope includes:

  • Tie Rod bounding
  • Previous TTW
  • Previous proximity tubes
  • Pre-frequency test [SG B only]
  • Proximity bounding
  • Post frequency test [SG B only]

3.2 Active degradation mechanisms found.

1R24 was the fifth inspection following replacement of the SGs. There are three degradation mechanisms identified (mechanical wear at the TSP, TTW and tie rod/tube bowing). These are listed in Table 3.2.1. (Note: This was not an ASME Code inspection so only a portion of the TSP wear is reported.)

Table 3.2.1 Indication List for 1R24 SG TSP Wear TTW Proximity (tie rod bowing)

A 161 55 14 B 356 93 8

Enclosure to 1CAN101306 Page 3 of 17 3.3 NDE techniques utilized for each degradation mechanism.

NDE Technique Mechanism Probe Detection ETSS Sizing ETSS Uncertainty Location

(%TW)

TTW Bobbin Note N/A 1.69 TSP Wear Bobbin 96043.1 Rev.1 96043.1 Rev. 1 1.85 TSP Wear Bobbin 96004.1 Rev.13 96004.1 Rev.13 4.51 TTW +Point' Note Note 1.51 TSP Wear +Point' 96910.1 Rev. 10 96910.1 Rev. 10 6.68 TTW X-Probe Note Note 1.38 TSP Wear X-Probe 11956.3 Rev. 0 11956.3 2.42 TSP Wear X-Probe 11956.4 Rev. 0 11956.4 4.60 TW Throughwall ETSS Examination Technical Specification Sheet Notes: Bobbin, +Point' and X-Probe are being extended for detection and sizing of TTW in the 1R24 ETSS validation document.

Bobbin: Detection only, sizing for information

+Point': Detection and sizing X-Probe: Detection and sizing 3.4 Location, orientation (if linear), and measured sizes (if available) of service induced indications.

The only service-induced mechanisms were mechanical wear at the TSPs and TTW. There were no wear indications associated with proximity tubes (tubes in close contact or contacting adjacent tubes due to tie rod bowing). Due to the large number of indications, these are listed in Section 3.7 below.

Based on the limited examination scope of 1R24, the TSP wear tables were not included. The TTW scope was a 100% examination of previous TTW based on the results from 1R23.

3.5 Number of tubes plugged during the inspection outage for each active degradation mechanism.

There were 16 tubes plugged in 1R24 with all of these tubes being stabilized. Listed below in Tables 3.5.1 and 3.5.2 is a summary of the plugged tubes for SG A and SG B, respectively:

Enclosure to 1CAN101306 Page 4 of 17 Table 3.5.1 SG A Repaired Tubes in 1R24 Row Tube Repair Type Reason 25 11 Plug and Stabilize Tie Rod Bowing 1st Span 25 12 Plug and Stabilize Tie Rod Bowing 1st Span 47 22 Plug and Stabilize Tie Rod Bowing 1st Span 48 23 Plug and Stabilize Tie Rod Bowing 1st Span 86 21 Plug and Stabilize Tie Rod Bowing 1st Span 109 8 Plug and Stabilize Tie Rod Bowing 1st Span 110 8 Plug and Stabilize Tie Rod Bowing 1st Span Table 3.5.2 SG B Repaired Tubes in 1R24 Row Tube Repair Type Reason 63 123 Plug and Stabilize Tie Rod Bowing 1st Span 64 122 Plug and Stabilize Tie Rod Bowing 1st Span 87 123 Plug and Stabilize Tie Rod Bowing 1st Span 88 122 Plug and Stabilize Tie Rod Bowing 1st Span 109 110 Plug and Stabilize Tie Rod Bowing 1st Span 110 107 Plug and Stabilize Tie Rod Bowing 1st Span 128 82 Plug and Stabilize Tie Rod Bowing 1st Span 129 85 Plug and Stabilize Tie Rod Bowing 1st Span 31 1 Plug and Stabilize Preventive, Tube Wear Depth 11S-85 3.6 Total number and percentage of tubes plugged to date.

There were no sleeves installed in either SG. The aggregate plugging information is listed in Table 3.6.1 below.

Enclosure to 1CAN101306 Page 5 of 17 Table 3.6.1 Cumulative Plugs in Service SG A Year Outage Installed Cumulative  % Plugged 2004 Fabrication 2 (welded) 2 0.013 2005 Baseline (1R19) 0 2 0.013 2007 First ISI 1R20 0 2 0.013 2008 1R21 8 10 0.064 2010 1R22 0 10 0.064 2011 1R23 7 17 0.109 2013 1R24 7 24 0.154 SG B Year Outage Installed Cumulative  % Plugged 2005 Fabrication 0 0 0 2005 Baseline (1R19) 0 0 0 2007 First ISI 1R20 1 1 0.006 2008 1R21 5 6 0.038 2010 1R22 0 6 0.038 2011 1R23 9 15 0.096 2013 1R24 9 24 0.154 Note - 15597 total tubes, so 0.1% = ~15 tubes 3.7 The results of condition monitoring, including the results of tube pulls and in-situ testing.

All condition monitoring requirements for the tubing performance criteria were met. There were no indications that exceeded performance criteria or in-situ screening limits. There was no tube pulls required.

The CMOA for 1R23 (previous outage) evaluated an OA of three operating cycles totaling 4.13 Effective Full Power Years (EFPY) to 1R26 (End of Cycle 26) which supported skip inspections for both 1R24 and 1R25 refueling outages. Only 1.32 EFPY has passed as of the 1R24 inspection; therefore the prior CMOA is still applicable. The following is a summary of the three damage mechanism results identified in 1R24:

Enclosure to 1CAN101306 Page 6 of 17 Tie Rod Bowing Based on 1R24 inspection results, the following observations are made concerning tie rod bowing in SG A:

  • All tie rod bowing in SG A is less than the historical projection curve used in the structural integrity justification of SGs.
  • Tie rod bowing increased between the 1R23 and 1R24 inspections and the SGs experienced only one cool-down loading between inspections.
  • The magnitude of bow in the first span tie rods has increased slightly from 1R23. The general trend is the net change between inspections appears to be less.
  • Tie rod bowing in both the outer and second ring of first-span tie rods are in the plastic range which means there will be some amount of residual bow during normal power operation.
  • The magnitude of bowing in spans above the first-span remains in the elastic range (e.g., no plastic set, except possibly a single tie rod that may have a small plastic set),

and the tie rods should straighten out at normal operating temperatures.

  • Bowing in first span now includes a second third-ring tie rod.
  • Based on the tie rod bow projections for the requested four allowable future heatup and cool-down cycles, it is predicted that four peripheral tie rods in the first span will contact the adjacent tube(s) during normal operation. Therefore, the affected tubes were removed from service (plugged and stabilized).

Based on 1R24 inspection results, the following observations are made concerning tie rod bowing in SG B:

  • All tie rod bowing in SG B is less than the historical projection curve used in the structural integrity justification of SGs.
  • Tie rod bowing increased between the 1R23 and 1R24 inspections and the SGs experienced only one cool-down loading between inspections.
  • The magnitude of bow in the first-span tie rods has increased and is now in the plastic range which means there will be some amount of residual bow during normal power operation.
  • The magnitude of bowing in spans above the first-span remains in the elastic range (e.g., no plastic set), and the tie rods should straighten out at normal operating temperatures.
  • Bowing in first span now includes two additional second-ring tie rods and a total of nine additional tubes with proximity signals.

Enclosure to 1CAN101306 Page 7 of 17

  • The increase in bowing over three cool-down cycles (5, 6 and 7) of the first-span periphery tie rods is consistent with the historical projections developed from the observed bowing in SG A.
  • Bowing in the 15th span is essentially unchanged between 1R23 and 1R24 (cool-down cycles 6 and 7).
  • There is now bowing in one tie rod in the 13th span.
  • The direction of tie rod bowing in the first span is not consistent with that observed in SG A. Bowing in SG A is all radially inward while some of the observed SG B bowing is circumferential. This was addressed in the site corrective action program CR-ANO 2011-1925.
  • A review of limited inspection results from Framatome Data Management System shows an apparent increase in low-level dents for 1R24. This is based on a review using 0.2 volts and higher.
  • Based on the tie rod bow projections for the requested four allowable future heatup and cool-down cycles, it is predicted that the peripheral tie rods in the first-span will contact the adjacent tube(s) during normal operation. Therefore, the affected tubes were removed from service (plugged and stabilized). The preventative plugging of the peripheral first-span tie rods is consistent with that performed in SG A.

Listed below in Figures 3.7.1 and 3.7.2 is the lateral bowing extents by location for the last five outages in the first span (bounding).

Enclosure to 1CAN101306 Page 8 of 17 Figure 3.7.1 SG A Bowing History (in lateral inches)

SG A - First Span Tie Rod Bow Projections (14 tie rods, 1 span, 3 rings) 2.0 1.8 1.6 1.4 Tie Rod Bow, inches 1.2 1.0 0.8 outer ring nd 0.6 2 ring rd 3 ring 0.4 historical projections rod-tube contact hot 0.2 tube-tube contact affected tubes plugged 0.0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 1R19 1R20 1R21 1R22 1R23 1R24 Cooldown Cycles

Enclosure to 1CAN101306 Page 9 of 17 Figure 3.7.2 SG B Bowing History (in lateral inches)

SG B - First Span Tie Rod Bow Projections (8 tie rods, 1 span, 2 rings) 2.0 1.8 1.6 1.4 Tie Rod Bow, inches 1.2 1.0 0.8 outer ring nd 0.6 2 ring rd 3 ring 0.4 historical projections rod-tube contact hot 0.2 tube-tube contact affected tubes plugged 0.0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 1R19 1R20 1R21 1R22 1R23 1R24 Cooldown Cycles

Enclosure to 1CAN101306 Page 10 of 17 TSP Wear As stated earlier, the scope of the 1R24 SG inspection was to monitor and assess tie rod bowing with additional inspection scope for low-level denting on the top TSP and TTW. All TSP wear identified in these inspections is summarized in Tables 3.7.1 and 3.7.2.

There were 14 new indications in SG A and 14 new indications in SB B in 1R24; however, review of 1R23 inspection data confirmed wear for 13 of these locations in SG A as well as 13 locations in SG B. The larger of the two new TSP wear indications (SG B R149-T1, 12S-0.64) has a depth of 24% TW. The probabilistic full-bundle model in the 1R23 OA used a distribution of new TSP wear up to 35% TW; therefore, the new indication is bounded by the 1R23 OA. The new indication in SG A is 14% TW, which is bounded by the flaw in SG B.

The probabilistic full-bundle model in the 1R23 OA assumed the maximum 1R23 growth rate of 9.37% TW/EFPY. Of the 160 (SG A) and 355 (SG B) repeat indications in 1R24, only one wear indication exceeded this growth rate (SG B R31-T1 11S -0.78) with 12.88% TW/EFPY growing from 13% TW in 1R23 to 30% TW in 1R24. This is a peripheral tube which is experiencing the highest growth rates at ANO-1. The growth is only a 3.5% TW/EFPY increase over the 1R23 maximum. Additionally, under the constant volume assumption over a three-cycle run, approximately half of the growth should occur in the first cycle and would be expected to decrease over the next two cycles and is therefore accounted for in the uncertainty of the 1R23 CMOA. However, a decision was made to conservatively plug R31-T1 in SG B based on the growth.

Table 3.7.1 Summary of 1R24 TSP Wear Depths SG A SG B Total TSP Wear Indications 161 356 New TSP Wear Indications 14 14 (Note) (1) (1)

Maximum Depth, Repeat 26 35

(%TW)

Maximum Depth, New (%TW) 14 24 Note: 1R23 inspection results for both SGs were reviewed for all new TSP wear indications.

The numbers in parentheses are the indications that are confirmed as new in 1R24 (i.e., There is no data present in 1R23.).

Enclosure to 1CAN101306 Page 11 of 17 Table 3.7.2 Summary of 1R24 TSP Wear Growth Rates SG A SG A SG B SG B 1R24 1R23 1R24 1R23 Maximum (% TW/EFPY) 6.82 7.12 12.88 9.37 95th (% TW/EFPY) 2.05 1.87 2.27 2.62 TTW After the ANO 1R23 inspection was completed, inspection in the first in-service inspection of the Three Mile Island, Unit 1 (TMI-1) EOTSGs detected numerous freespan (not coincident with a tube support or tubesheet) Bobbin coil Absolute Drift Indications. Scrutiny of these calls concluded that these were actually indications of TTW in the mid-span regions of the SG. This resulted in a post-1R23 re-analysis of ANO-1 inspection data, beginning with the first in-service inspection at 1R20 that confirmed a total of 126 indications of TTW (48 in SG A, and 78 in SG B). A % TW depth was assigned based on a bobbin voltage correlation to the TMI-1 data.

Prior to 1R24, qualification for detection and sizing of TTW was performed for Bobbin, X-probe (Array) and +Point' coil which was implemented at the 1R24 inspection. As Bobbin coil is limited in that it cannot distinguish multiple wear indications at the same location, X-probe or

+Point' is used for the official depth measurements; however, as the historical data for TTW thru 1R23 has been sized only with Bobbin coil, the 1R24 inspection data is used to bridge the gap between techniques. This is done by listing the historical Bobbin coil depths, including 1R24 Bobbin, alongside the 1R24 X-probe depths. Tables 3.7.5 and 3.7.6 tabulate the TTW indications for both SGs. As a check, the 1R23 Bobbin coil results were resized using the Bobbin coil calibration curve and the average difference was < 1% TW; therefore, the 1R23 Bobbin coil results were left unchanged.

Enclosure to 1CAN101306 Page 12 of 17 Table 3.7.3 Summary of 1R24 TTW Depths SG A SB B Total Indications /

55/49 93 / 80 Tubes (Note 1)

New Indications / Tubes 3/2 7/6 (Note 2) (0 / 0) (7 / 6)

Maximum Depth, New 5 7

(%TW)

Maximum Depth, 14 22 Repeat (%TW)

Notes:

1. Number of indications and reported depths are from the X-probe (Array) results.
2. 1R23 inspection results for both SGs were reviewed for all new TTW indications.

The numbers in parentheses are the indications and tubes that are confirmed as new in 1R24 (i.e. There is no data present in 1R23.).

Table 3.7.4 Summary of 1R24 TTW Growth Rates SG A SG A Array- SG B SG B Array-Bobbin Bobbin Bobbin Bobbin (Note 1) (Note 2) (Note 1) (Note 2)

Average (%TW/EFPY) 1.31 0.26 1.41 0.14 Maximum (%TW/EFPY) 6.44 3.79 9.34 9.01 95th (%TW/EFPY) 1.77 1.53 6.44 4.89 Notes:

1. Due to the difference in techniques, these growth rates are calculated using just the Bobbin depths.
2. Due to the difference in techniques, these growth rates are calculated using the 1R24 Array depths and 1R23 Bobbin depths.

Enclosure to 1CAN101306 Page 13 of 17 Table 3.7.5 SG A TTW Historical Summary X-Probe Bobbin (%TW) (%TW)

Notes Row Tube Loc In 1R20 1R21 1R23 1R24 1R24 42 22 8 18.50 6 7 7 9 7 2 wear scars 43 22 8 18.94 8 9 9 10 N/A by Array 46 89 8 18.27 0 0 7 9 6 47 21 8 17.69 N/A N/A N/A 8 5 New in 1R24 New in 1R24 50 23 8 17.18 N/A N/A N/A 9 N/A 2 wear scars by Array 61 30 8 18.84 0 0 12 13 13 62 29 8 18.80 0 0 13 14 14 71 109 8 18.53 0 0 6 8 6 71 110 8 18.43 0 0 11 12 9 72 107 8 18.29 0 0 8 10 9 72 108 8 18.26 0 0 9 10 9 72 110 8 18.48 0 0 10 11 9 74 22 8 18.16 6 7 7 9 5 74 109 8 17.93 0 0 13 14 13 74 110 8 18.06 0 0 16 16 13 75 108 8 17.73 0 0 9 10 8 2 wear scars 75 109 8 17.89 0 0 10 11 N/A by Array 77 22 8 17.34 5 6 6 8 7 2 wear scars 77 25 8 18.81 0 0 7 9 N/A by Array 77 108 8 16.88 0 0 8 9 9 2 wear scars 77 109 8 17.12 0 0 11 12 N/A by Array 78 21 8 17.19 5 7 7 8 7 81 21 8 17.89 9 9 9 10 10 81 110 8 17.99 0 0 10 11 9 2 wear scars 81 111 8 18.33 0 0 15 15 N/A by Array 82 20 8 17.34 6 7 7 9 9 82 31 8 18.23 0 0 6 8 8 82 110 8 18.40 0 0 9 10 9 82 111 7 20.95 6 7 7 8 9

Enclosure to 1CAN101306 Page 14 of 17 X-Probe Bobbin (%TW) (%TW)

Notes Row Tube Loc In 1R20 1R21 1R23 1R24 1R24 83 31 8 17.81 0 0 7 9 9 90 106 7 18.63 12 12 11 12 11 91 108 7 18.79 11 12 12 12 12 99 101 8 17.88 0 2 7 9 9 100 100 8 17.80 0 0 7 9 8 107 87 8 18.14 0 0 6 8 7 107 88 8 18.36 0 3 7 8 7 117 35 8 18.18 0 3 9 10 9 118 35 8 18.37 0 3 9 10 9 118 87 8 18.50 8 7 8 9 6 118 90 7 20.02 7 6 6 8 6 119 44 8 18.11 0 4 9 10 7 119 70 8 18.28 0 0 9 10 9 119 71 8 18.25 0 3 8 10 9 No Degradation 119 84 7 19.49 6 7 6 8 N/A Found with Array 120 73 8 17.21 0 0 8 9 9 121 73 8 17.65 0 0 9 11 10 124 62 6 20.10 6 7 7 9 6 124 63 6 20.02 7 7 7 9 6 126 52 8 17.54 0 3 8 10 9 127 51 8 17.07 0 3 8 10 10

Enclosure to 1CAN101306 Page 15 of 17 Table 3.7.6 SG B TTW Historical Summary X-Probe Bobbin (%TW) (%TW)

Notes Row Tube Loc In 1R20 1R21 1R23 1R24 1R24 20 51 8 18.34 10 9 10 11 10 20 52 8 18.41 10 9 10 12 8 21 47 8 18.50 7 8 9 11 6 21 50 7 19.51 13 13 12 13 14 21 50 8 18.70 7 8 8 10 7 21 51 7 19.41 14 12 13 15 13 22 49 8 18.34 8 9 10 11 6 22 51 8 18.88 8 9 9 11 8 22 62 8 18.86 8 9 9 11 9 2 wear scars 22 63 8 18.59 8 10 10 11 N/A by Array 23 59 8 17.74 7 6 6 8 7 2 wear scars 25 71 8 17.75 11 10 11 12 N/A by Array 2 wear scars 25 72 8 17.68 13 13 14 14 N/A by Array 26 39 8 18.14 0 11 10 11 8 26 72 8 18.02 7 10 8 10 6 Newly 26 73 8 16.94 9 7 reported in 1R24 27 69 8 18.28 7 8 8 10 7 28 67 7 20.13 9 10 8 11 10 28 68 7 19.75 10 10 9 11 9 28 68 8 18.58 8 7 8 9 9 28 69 8 18.01 8 8 9 10 8 28 76 8 17.13 14 13 13 14 13 2 wear scars 28 77 8 17.54 14 13 15 14 N/A by Array Newly 29 68 8 17.09 7 6 reported in 1R24 29 77 8 18.67 9 9 10 11 8 31 34 8 18.35 12 13 13 14 11 31 35 8 18.24 9 10 10 12 10 31 38 8 17.98 7 8 6 9 6

Enclosure to 1CAN101306 Page 16 of 17 X-Probe Bobbin (%TW) (%TW)

Notes Row Tube Loc In 1R20 1R21 1R23 1R24 1R24 Newly 31 61 7 18.69 7 7 reported in 1R24 31 62 7 19.37 5 5 6 7 8 31 62 8 19.03 5 8 10 11 10 31 63 8 19.28 0 0 10 11 10 31 74 8 18.55 0 0 7 9 8 32 74 8 18.60 0 0 7 9 7 34 27 8 19.37 9 10 9 10 7 34 55 8 18.81 0 0 7 19 19 34 56 8 18.92 0 0 9 18 17 34 89 8 18.41 6 6 6 8 6 2 wear scars 34 90 8 18.04 7 8 8 10 N/A by Array 35 28 8 19.29 7 8 7 9 8 38 86 8 19.89 0 0 9 11 10 38 87 8 19.73 0 0 9 10 10 39 37 8 17.95 7 7 7 9 8 39 91 8 19.64 0 0 6 8 7 39 92 8 19.77 0 0 8 9 8 40 36 8 18.17 8 8 8 10 9 44 25 8 18.86 0 6 7 8 5 46 21 8 18.22 8 8 8 10 9 46 100 8 18.40 4 4 15 14 14 47 21 8 17.79 7 7 7 9 6 47 99 8 18.54 3 3 13 14 12 58 26 8 18.86 7 7 7 8 7 60 21 8 18.32 6 7 6 8 7 Newly reported in 66 21 8 17.46 N/A N/A N/A 9 N/A 1R24, 2 wear scars by Array Newly 67 22 8 18.81 N/A N/A N/A 7 5 reported in 1R24 67 108 8 18.51 5 9 8 10 8

Enclosure to 1CAN101306 Page 17 of 17 X-Probe Bobbin (%TW) (%TW)

Notes Row Tube Loc In 1R20 1R21 1R23 1R24 1R24 68 110 8 18.33 3 9 10 10 8 75 114 8 18.66 6 7 8 8 7 2 wear scars 78 20 8 18.28 7 7 7 9 N/A by Array 89 25 8 17.67 9 9 9 11 9 90 25 8 17.84 9 8 10 11 10 102 102 8 17.20 0 5 6 7 7 103 21 8 17.69 7 5 7 9 7 103 22 8 17.40 7 7 7 9 7 105 23 8 18.42 5 5 7 8 8 106 24 8 18.75 5 6 7 9 7 114 82 8 18.86 0 0 10 11 10 114 83 8 18.83 0 0 11 12 10 115 30 8 17.82 5 11 11 12 11 115 31 8 18.14 6 11 13 13 10 116 29 7 19.76 9 27 26 22 22 117 29 7 19.82 10 27 26 23 21 118 28 8 18.07 6 6 6 8 5 118 88 8 18.34 5 7 7 9 5 119 25 7 20.08 16 14 16 15 13 119 28 7 19.83 8 7 7 8 6 2 wear scars 119 29 7 19.70 9 9 9 11 N/A by Array 120 25 7 20.22 15 9 14 14 13 123 32 8 18.18 5 7 7 9 5 Newly 128 44 7 19.01 9 6 reported in 1R24 128 45 7 20.17 8 8 7 10 7 128 45 8 17.90 4 5 5 5 4 128 60 8 18.64 5 5 6 7 6 129 30 8 17.55 8 8 8 10 7

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