ML070330020

Summary of Conference Call Regarding Steam Generator Tube Inspections

ML070330020
Person / Time
Site:	Sequoyah
Issue date:	12/11/2006
From:	Moroney B NRC/NRR/ADRO/DORL/LPLII-2
To:	Singer K Tennessee Valley Authority
Moroney B, NRR/DORL, 415-3974
Shared Package
ML070320259	List: ML070320194 ML070330020
References
TAC MD3534
Download: ML070330020 (5)

Text

I SON Unit 2 RFO 14 STEAM GENERATOR EDDY CURRENT TESTING 12/11/2006 10:31:30 AM STEAM GENERATOR 1 2 3 4 TOTAL DEGRADATION ACTUAL ASSESSMENT TUBES TUBES TUBES TUBES TO BE TUBE REPAIR DAMAGE MECHANISMS NDICATIONS TO PLUG INDICATIONS ITO PLUG INDICATIONS TO PLUG INDICATIONS TO PLUG PLUGGED PROJECTIONS AVB WEAR 13 1 41 0 20 0 17 0 1 2 COLD LEG THINNING (SON2 ONLY) 37 0 70 1 48 1 40 0 2. 10 FREESPAN ODSCC 0 0 1 1 1 1 0 0 2 2 FREESPAN PWSCC 0 0 0 !0 0. 0 0 0 0 5 LOOSE PARTS DAMAGE 0 0 0 0 0 0 0 0 0 14 SLUDGE PILE CRACKING 0 0 0 0 0 0 0 0 0 6 TSP OSCC AXIAL (ARC) 437 7 502 2 571 5 1232 5 19 27 TSP OOSCC CIRC (DENTS) 1 1 0 0 0 0 0 0 1 2 "rs oDscc AXIAL 0 O 0 O 1 1 2 2 3 23 TTS ODSCC CIRC 0 0 2 2 1 1 1 1 4 9 U-SEND OOSCC AXIAL 0 0 0 0 0 0 0 0 0 0 U-BENO ODSCC CIRC 0 0 0 0 0 0 0 0 0 0 TSP PWSCC AXIAL 1 1 0 0 1 1 0 0 2 2 TSP PWSCCCIRC (DENTS) 0 0 0 0 2 1 0 0 1 5 TTS PWSCC AXIAL 0 0 0 0 0 0 2 1 1 20 TTS PWSCC CIRC 0 0 1 1 0 0 0 0 1 5 U-BEND PWSCC AXIAL 1 1 0 0 0 0 0 0 1 4 U-BEND PWSCC CIRC 0 0 3 2 0 0 0 0 2 1 PRE-HEATER WEAR (WBN1 ONLY) 0 0 0 0 0 0 0 0 0 0 OTHER/PREVENTIVE 0 0 2 2 0 0 0 0 2 2 TOTALS IND/PLUG (Current) 490 622 11 645 11 1294 9 42 139 Total Previously Plugged ... ,, . 77 , *. i 171 1 126 123 497 PLUG TOTALS 88 182 , 137 132 539 TOTAL SLEEVES (Current) 0 0 0-,' 0 ... 0 0 Total Previously Sleeved , 0 .. 0: o *'-," .* 0" SLEEVE TOTALS 0,. 0 ' ,0 .0 TOTAL PERCENT PLUGGED ,.*' 4 4.0.

EQUIVALENT" EQUIVALNT

._____,,_:__ 2564% *I4.0% 3.9% 4.0% I:,

Attachment

SG ROW COL CAL LEG TEST ANGLE VOLTS INDICATION LOCATION SURFACE CHARACTERIZATION AVG. DEPTH LENGTH PDA (for indications > 0.5 +Pt volts)

AVB WEAR (Maximum Depth) 1 37 62 18 H ZBAZZ 0 1.25 42 AV3+.00 AVB WEAR COLD LEG THINNING (Maximum Depth) 2 33 16 10 C ZBAZZ 89 1.57 58 C03-.06 C/L THINNING O0 VOLUMETRIC 2 12 65 50 H ZPSNM 12 0.37 SVI HTS+7.66 0 VOLUMETRIC AXIAL PWSCC AT HTS 4 4 25 52 "H ZPSNM 15 0.95 SAI HTS-8.13 PWSCC HTS AXIAL 3.12 4 4 25 52 H ZPSNM 30 3.04 SAI HTS-10.64 PWSCC HTS AXIAL 1.96 AXIAL PWSCC TSP NEAR DENT 3 12 4 49 H ZPSNM 18 0.53 SAI H01-.25 PWSCC TSP AXIAL 36.5 0.26 1 29 78 53 H ZPSNM 14 0.41 SAI H05+.19 I PWSCC TSP. AXIAL AXIAL PWSCC U-BEND TANGENT 1 1 52 38 C ZPU24 22 1.86 SAI H07+3.94 I PWSCC UBEND AXIAL 47.6 0.16 CIRC PWSCC HTS 2 20 70 31 H ZPSNM 24 0.41 SCI HTS-.11 PWSCC HTS CIRC CIRC PWSCC TSP NEAR DENT 3 12 56 49 H ZPSNM 41 0.85 SCI H07+.03 PWSCC TSP CIRC 3 12 56 57 H ZGSMB 34 1.49 SCI H07+.03 PWSCC TSP CIRC CIRC PWSCC U-BEND 2 4 53 38 H ZPU24 32 0.61 SCI H07+22.26 PWSCC UBEND CIRC 3.42 2 3 94 41 H ZPU24 24 0.54 SCI H07+16.23 PWSCC UBEND CIRC 2.54 2 3 94 41 H ZPU24 32 0.77 SCI H07÷18.72 PWSCC UBEND CIRC 4.17 AXIAL ODSCC HTS 4 22 28 26 H ZPSNM 63 0.37 SAt HTS-.08 ODSCC HTS AXIAL 4 26 33 25 H ZPSNM 129 0.22 SAI HTS-.10 ODSCC HTS AXIAL 3 26 42 33 H ZPSNM 100 0.09 SAI HTS-.07 ODSCC HTS AXIAL AXIAL ODSCC TSP 2 3 5 45 H ZPSNM 108 0.19 SAI H03+.30 ODSCC TSP AXIAL 2 7 20 45 H ZPSNM 97 0.17 SAI H05+.24 ODSCC TSP AXIAL 1 35 19 42 H ZPSNM 105 0.25 SAI H01-,01 ODSCC TSP AXIAL 1 43 59 42 H ZPSNM 132 0.10 SAI H01+.16 ODSCC TSP AXIAL 1 5 72 48 H ZPSNM 117 0.16 SAI H03-.11 ODSCC TSP AXIAL AXIAL ODSCC FREESPAN 2 8 2 45 H ZPSNM 104 0.17 SAI HO1+.49 ODSCC FREESPAN AXIAL 3 31 61 52 H ZPSNM 99 0.32 SAI HTS+47.63 ODSCC FREESPAN AXIAL CIRC ODSCC HTS 2 15 38 24 H ZPSNM 55 0.16 SCI HTS+.05 ODSCC HTS CIRC 3 11 28 32 H ZPSNM 29 0.20 SCI HTS-.01 ODSCC HTS CIRC 2 13 67 28 H ZPSNM 27 0.17 SCI HTS-.17 ODSCC HTS CIRC 4 8 71 35 H ZPSNM 25 0.25 SCI HTS+.00 ODSCC HTS CIRC CIRC ODSCC TSP 1 45 39 47 H ZPSNM 79 0.50 SCI H07-.25 0 ODSCC TSP CIRC

1. Discuss any trends in the amount of primary-to-secondary leakage observed during the recently completed cycle.

SQN Unit 2 observed no detectable leakage during the recently completed cycle.

2. Discuss whether any secondary side pressure tests were performed during the outage and the associated results.

SQN did not perform any secondary side pressure tests during RFO-14.

3. Discuss any exceptions taken to the industry guidelines.

No exceptions.

4. For each SG, provide a description of the inspections performed including the areas examined and the probes used (e.g., dents/dings, sleeves, expansion -transition, U-bends with a rotating probe), the scope of the inspection (e.g., 100% dents / dings greater than 5 volts and a 20% sample between 2 and 5 volts), and the expansion criteria.

• 100% Full-length bobbin examination in all 4 SGs.

• 100% hot leg top of tubesheet (TTS) RPC examination in all 4 SGs using a plus point probe +2"/-8" (Ref. WCAP-14797)

• 100% of low Row U-bends using a mid range magnetic biased ZETEC +Point (or MHI probe) Row 1-4 U-Bend probe

• 100% Row 5 through 8 U-Bend using a MHI probe (or +Point) in all SGs.

• 100% freespan dings > 2 volts (Cycle 13) from HTS to H07 using the +Pt probe

• 100% TSPs HO I to C07 dented greater than or equal to 2 volts (Cycle 13) using the +Pt probe

• 100% of AVB locations with dents with a +Pt probe (Ref. Corp PER 03-000055-000).

• 100% of MBM with dings with a +Pt probe (Ref. Corp PER 03-000023-000).

• 100% of all free-span dents or dings in the U-bend region (any voltage) using the

+Pt probe (Ref. Corp. PER 03-000055-000).

100% DS~s approximately > l v will be examined and reviewed for preventive plugging.

OXPs and BLGs within the hot leg +2/-8" Top of Tubeshect inspection distance have been plus point examined.

5. For each area examined (e.g., tube supports, dent.dings, sleeves, etc), provide a summary of the number of indications identified to-date of each degradation mode (e.g., number of circumferential priamry water stress corrosion cracking indicaitons at the expansion transition). In particuair, address whether tube interity (structural and accident induced leakage integrity) was maintained during the previous operating cycle. In addition, discuss whether any location exhibited a degradation mode that had not previously been observed at this location at this unit (e.g.,

observed circumferential primary water stress corrosion cracking at the expansion transition for the first time at his unit).

See attached summary and Condition Monitoring New Axial ODSCC Freespan not associated with ding/dents (first detected by bobbin)

New Circ ODSCC at TSP associated with a 35v dent

6. Describe repair/plugging plans.

See attached summary 42 tubes presently on the plugging list.

7. Describe in-situ pressure test and tube pull plans and results (as applicable and if available).

Nothing requiring In-Situ to date.

SG 4 Row 22 Column 70 is planned to have the first two hot leg intersection pulled.

8. Describe the schedule for steam SG related activities during the remainder of the current outage.

Presently in close out. Retests only

9. Discuss the following regarding loose parts:

- what inspections are performed to detect loose parts; 100% Full length Bobbin Coil exams and 100% +Pt at top of tubesheet

- a description of any loose parts detected and their location within the SG; PLPs have been reported and those in SG 3 have looked at by FOSAR

- if the loose parts were removed from the SG; No loose part detected to date.

- indications of tube damage associated with the loose parts; and No tube damage has been reported by ET detected associated with loose parts. Analysts have been sensitized on loose part damage. The enhanced technique for loose part wear detection is utilized.

- the source or nature of the lose parts if known.

No loose parts detected to date.

10. Discuss the results of any secondary side inspections.

SG.3 only FOSAR thus far. Remaining SGs to be examined in the next few days.

11. Discuss any unexpected or unusual results.

none

12. For plants with Once-Through SGs A. If you have Bacock and Wilcox (B&W) welded plugs installed in the steam generators, be prepared to discuss the actions taken in response to Framatome's notification of the dffect of tubesheet hole dilation on the service life of B&W welded plugs.

NA B. Discuss any actions taken in response to the severed tube issue during the outage (NRC information Notice (IN) 2002-02 and IN 2002-02, Supplement 1. If actions are comlete, please indicate so.

NA