ML061220448

Attachment 2 to Comanche Peak Conference Call

ML061220448
Person / Time
Site:	Comanche Peak
Issue date:	05/18/2006
From:	Office of Nuclear Reactor Regulation
To:
Thadani M, NRR/DLPM, 415-1476
References
Download: ML061220448 (5)

Text

Io. 2C, i iOll ;I) Hr TXUP 1RF 1 INRR S/G (:onfer'ence Call Specific Ollestionis Discuss whether any priinary to secondary leakage existed in this Ullit prior to shutdown.

None detectable

2. Discuss the results of secondary side pressure rests.

• Secondaty Side pressure tests are not schieduled to be performied in IRFI 1.

3. For each SG, provide a general description of areas examined. including the expansion criteria utilized and type of probe used in each area. Also. be prepared to discuss your inspection of the nibe within the tubesheet. particularly the portion of the tube below the expansiont/transirion reeion.

O The following is tie base scope inspection plan for the IRFI 1 outage in October 2005.

Expansion of the inspection will be based on Tech Spec and EPRI guideline criteria.

Inspection will be perfomied in all four SGs and the inspection scope is the samle in all four:

1) 100°o fill bobbin examination of non-sleeved tubes in Rows 5 and greater and 1 00°o bobbin inspection in the hot and cold leg straighit sections of Rows 1 through 4 using a 0.610'" diameter probe *.

2) 100'o bobbin examination of tubes with sleeves in rows 5 and above from the cold leg to the top of the sleeve in the hot leg using a 0.610'" diameter probe.

3) 100% +Pt examination of hard rolled tubes at the hot leg top of nibesheet (TTS -/-

3")

4) 100% +'Pt inspection of WEXTEX nibes at the hot leg tubesheet (TTS +3" thiu tuibe end hot)

5) 100% +Pt inspection of U-bends in rows 1 through 16

6) 25% fPt examination of tubes expanded at cold leg baffles B (C2) and D (C3)

7) 100%. +Pt examination of dents, regardless of voltage. within + 1" from AVB locations

8) 100% + Pt examiniation of AVBM wvear scars and 20%' of baffle wear scars

9) 100°. -;-Pt examination of Ilix residual indications (> 1.5 volts as measured by bobbin) and hot leg dented intersections > 5 volts (as measured by bobbin) according to the requirements of GL 95-05

10) 100% +Pt examination of all bobbin coil "I" codes (except DSI < 1.0 volt at hot leg supports) for flaw confiniuation and characterization.

11) 100% +Pt inspection of all dented TSP intersections at the H3 TSP > 2 volts

12) 20% +Pt inspection of freespan dings > 2 volts and < 5 volts between TSH and H3

13) 100%o +Pt inspection of freespanldings> 5 volts

14) 20% +Pt freespan paired ding inspection between the top 2 TSPs (hot & cold legs)

• 540 wide 2roove bobbin used for HL low row stiaioht sections above TG sleeves and 520 wtide croove bobbiln iusc cl for HL low row str1aieht sectiois abovc Alloy SOO slevcs.

Attachlwnt 2

10 20 G. tlrs u i10CC 11 20%N +PT futll IenotlI inspection of IIG sleeves initalled in lIRF09. inspectionl exten, is +1-3" from sleeve ends (SGs 2.3.& 4)

16) S0°io part le112th1 illspeCTiOn of TIG sleeves +!- 3 from trop of sleeve end (SGs 2.3.&- 4)

I) lO0 fulMl leng!th inspection of the TIG sleeves installed in I RF09 ulsinlg 0.54 ilCI diameter bobbin probt: to look for restriction (collapse or partial collapse) in the sleeve (SGs 2,3..&:4)

IS) 100% +Point fiull lenllth inspecTioln of Alloy S00 sleeves installed ini IRF-10.

inspection extent is _ 3' from sleeve ends

19) 100% mnbe plug video inspection

20) Tube bundle seconhaiy side video inspection including a limited scope TTS in-bundle inspection and FOSAR at TTS and cold leg baffle plate B

-1. Discuss ally exceptions taken to indilstry guidefilles.

No exceptions to industry guidelines have been taken and none are planned.

5. Provide a sumnmary of the number of indications identified to-date of each degradation mode and SG tube location (e.g., tube-suippont-plate. top-of-nubesheet. etc.). Also provide information, such a; voltages. and estimated depths and lengths of the most significant indications.

Indlicatlion Sunmmaryv Tnble

TS HTS HTS HTS Free- Free- TSP Pre- U-bend U-bend ToTal TSP SG C irc Circ Axial Vol Span Span Vol heater Circ Axial Repairs DSIs O-D ID ID Axial Vol ID ID OD _ Wear

_____ ~>40% _ _ _

1 6_ 1 2 _ 16 32 9_ 1 4 1 2 17 30 3 2.3 1 2 _I 27 350

__ _ ___ _____ ____3 4 57 1 2 2 1 1 64 263 Total 9:5 3 1 4 11 i1 2 2 4_ 1 124 360 HITS Circ OD - Largest Voltage = 0.27 HTS Circ: OD - Longest Extent = 3030 HTS Circ ID - Largest Voltage = 0.63 HTS Circ ID - Longest Extent = 1000 HTS A.xiil OD - Largest Voltage = 0.12 HTS Axiil OD - Longest Extent = 0.28" Freespan Axial OD - Largest Voltage = 0.45 Freespan Axial OD - Longest Extent = 33.53" Freespan Volumetric - Largest Voltage = 0.09 eF Z 100, Hr-.

1O02j, Frlcpau V'olumetric - Larmest Extent = 0.2O5 x 0.44" Tu *e Supporr Volumietric - Largest Voltage = 0.41 Tu')e Support Volumietric - Longest Extent = 0.17" x 0.41" Pre-lheater Wear - Deepest Flaw =4-i5%b U-]3end Circ ID - Larmest Voltaae = 0.65 U-]3end Circ ID - Longest Extent = 420 Tube Support Axial OD - LargLest Volrage = 0.9-5, Repair Limift > 1.0 Volt I* In addition to the flaws identified by ECT there are 7 tubes oln the repair list du-e to partially collapsed TIG welded sleeves.

6. Describe repair/plugging plans for the SG tubes that meet thle repair/plugging criteria.

• All crack-like indications, sizable wear greater than 40% at AAVBs and baffle plates will be plugged. Leak tight sleeves and leak limiting sleeves with detectable degradation will be plugged. Also. sizable loose part wear greater than 40% or loose part wear less than thle repair limit where the loose part can not be removed will be plugged.

7. Discuss the previous history of SG tube inspection results, including any "look backs" performied, specifically for siglnificant indications or indications wlhere look backs are used in support of dispositioning (e.g., manufacturing burnish marks).

• There have been no significant indications reported to date. Prior cycle ECT data will be reviewed following the inspection to provide growth rate infonration in support of thle operational assessment. Historical data is also used to ideutify bobbin signals which exhibit change may therefore be indicative of cracking. Bobbin signals which are present in the first ISI and exhibit no change relative to the current data are recorded in the database wi:1i a tracking flag. Tlhose simgals which show change are tested with a +Point coil to dererminte whether ihe bobbin indication is indicative of a flaw. At CPSES both Resolution analysts must independently review the historical data and conlcur that the indicationl has not changed. Otherwise, the indication is tested with the +Point coil. The list of bobbin I codes subject to review for change is listed below.

• DEI - Distorted Expansion Indication

• DFI - Differential Freespan Indication

• DNI - Freespan Ding Indicatioti

, DTI - Distorted Tubeslheet Indication

• FSD - Freespaii Differential Signal

• . LPI - Loose Part with Indication

• MBM- Manufaclturing Burnish Mark

• QI - Non-Quantifiable Indication 10 20 01> Idnl Wu .

S. Discuss. in general. newv inspection findings (e.g.. degradation inode or location of degradation flew ro this Ili[1).

One axial ID indication has been detected in the U-benld of Row 13 (Colunin4 of SC: 4. Tle indication is 0.33 volts and is 0.43 inches long. The phase angle of the signal is 14 degree:

which would indicate a depth of less thain 40% TW. Review of the IR.F10 ECT data showu.

a simall signal present at the same location but wvith a lower phase angle. The IRFI 1 data may represent shallow PWSCC or altemnately. an ID surface scratch. The indication hl-as been conservatively treated as though it is PWSCC. The tube is on Thle repair list and the

+Point examination programin has been expanded (in accordmnce with a Westin-house Owners Group report on this subject) to include all u-bends through Row 25 in SG 4.

9. Discuss your use or reliance on inspection probes (eddy current or ultrasonic) other than bobbin and typical rotating probes, if applicable.

• 1No probes other than bobbin and typical rotating probes are being used.

10. Describe in-sim pressure rest plans and results, if applicable and available, including tube selection ciiteria.

• Tube selection for in situ testing will follow the methodology prescribed by the EPRI guideline. To date, no indications meer the initial screeninga criteria.

11. Describe tube pull plans and preliininamy results. if applicable and available: include tube selection criteria.

a No rube pulls are planned.

12. Discuss the assessment of tube integrity for the previous operating cycle (i.e., condition uonlitoling).

• Assessmnent of tube integrity for the current operating cycle (cycle 11) will follow a methodology consistent with the EPRI tube integrity guideline. To date, no indications have been detected that challenge leakage or tube integrity.

13. Provide the schedule for SG-related activities durin2 the remainder of the current oumage.

• ECT inspection completion - October 2 3rd

• Plugging completion - October 2 th

• Manway installation - October 3 0 th

14. Discuss the following regarding loose parts:

a) What inspectionls are performed to detect loose palts.

• Video inspection of the itanulus, tubelane. and T-slot at the TTS of all 4 SGs

• Video inspection of the T-Slot and annulus region of B Baffle Plate (C2) for all 4 SGs

• In-bundle of TTS in response to +Pt inspection

• As applicable response to +Pt inspection of B Baffle Plate b) Describe if any loose parts wvere detected and their location within thle SG.

4-

1o02C0' a ICCC H; 4 ECT has detected a total of 52 tubes Nviih PLP (possible loose part) indications. The majority are located on rop of the hot leg rnbeilleer and lhave been reported in previous examinations. Video inspection has also idenrtified small foreign objects on top of the coldi lea nubesheer. No loose parts were observed over baffle plate B wlhere feedwarer flow enters the tube bundle during, nonnal operation. This reresents a significant improveluent ftoin prior cycles and reflects success in preventing loose parts ingress into The SGs. Video inspection has been completed in all four SGs.

C) If loose palTs were removed fono The SG.

• Observed parts are retrieved if feasible. A total of 10 small loose parts have been removed between the four SGs. All other visually verified loose parts that were not retrieved have been evaluated and can safely remain in thle SG without any adverse impact on cycle 12 operation.

d) Indications of damage associated with loose parts. and

• ECT and visual inspection data does not indicate any ntbe damnage from PLP (possible loose part) indications e) The source or nature of the loose parts if known.

• Video inspection data sbows that mnany of the PLP indications are actually pieces of hardened sludge or scale which broke apart during, retrieval attempts. Others are small birs of wire, wveld slag, etc., whose oriain is unkiniown.

15. Discuss any changes to data analysis guidelines that will be implemented during the outage.

• No sianificant changes have been made to the data analysis methodology used in the previous IRF1O eaminlation. Minor chances were made to the document at the be-iinnina of the inspection to clarif' personnel responsibilities, update training requirements. and add reporting acronyms.