ML022670682
| ML022670682 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 08/19/2002 |
| From: | Southern California Edison Co |
| To: | Office of Nuclear Reactor Regulation |
| Wang A, NRR/DLPM, 415-1445 | |
| Shared Package | |
| ml022670195 | List: |
| References | |
| TAC MB4659 | |
| Download: ML022670682 (18) | |
Text
SONGS Unit 2 Steam Generator Inspections 2C12 Update with the NRC June 3, 2000
SONGS Unit 2 Background Two (2) steam generators Supplied by Combustion Engineering Designated SG 88 & 89 SG88 - 8626 tubes in service (180 sleeved)
SG89 - 8585 tubes in service (103 sleeved)
Recent Exam Outages Current Refueling Outage (2C 12) 14.7 EFPY Prior Refueling Outage (2C11) 13.3 EFPY Prior Refueling Outage (2C10) 11.7 EFPY Prior Mid-cycle Exam (2M9) 10.8 EFPY
& Performed chemical cleaning of secondary side 08/19/2002 2
SONGS Steam Generator 08/19/2002 3
Completion Status as of 6/3/2002
"* Bobbin ECT Inspection - Complete
"* +Point ECT Inspection - Complete in SG89, testing continues in SG88, 98% Complete
"* Sludge Lancing/Visual Insp - Complete SG89, setting up SG88
"* In-situ Testing - In progress SG89, 2 locations
"* Sleeving - Following In-situ
"* Plugging - Following Sleeving 08/19/2002 4
Discussion Points (DP)
DP-1) Discuss whether any primary to secondary leakage existed in this unit prior to shutdown
- No primary to secondary leakage was detected prior to shutdown of this unit DP-2) Discuss the results of secondary side hydrostatic tests
- No hydrostatic tests planned since no primary 08/19/200O secondary leakage during operation 5
DP-3) Description of Areas Examined Bobbin Exam Full length exam of in-service tubes (100%)
Rotating Exams (+Point)
- Hot leg top-of-tubesheet locations (100%)
- Cold leg top-of-tubesheet locations (20%)
- Rows 1 thru 3 U-bend locations (100%)
- Installed sleeves (100%)
- Special Interest Locations -10,050 locations
"* Non-quantifiable bobbin indications (I-codes) -400 locations
"* Dents > or = 2volts (100%) -8600 locations
"* Dings > or = 5 volts at hot leg locations -200 locations
- Tube wear at supports (100%) -850 locations 08/19/2002 6
Secondary Side Inspections
- Visual inspection for foreign objects, prior to and upon completion of sludge lancing.
- Two loose parts identified and retrieved from SG89 08/19/2002 7
DP-4) Inspection Results and Repair Candidates as of 6/2/02 SG 88 SG 89 TSH Circ, Axial, Volumetric
-81
'49 TSC Circ, Axial, Volumetric 0 Freespan Axial
-6^07 Tube Support Axial
-23
-13 Tube Support Wear(>44%TW)
~0
-0 Tube Support Wear(Preventative)
--14
-23 Preventative
-?
-?
Total Repairs
-124
.-92 08/19/2002 8
DP-5) Tube Repair Criteria and Techniques
"* Repair
- All indications exceeding Technical Specification repair criteria
- All crack-like indications
"* Sleeves will be installed in tubes with crack-like indications top-of-tubesheet within the sleeve extent
"* Circumferentially oriented indications will be stabilized or sleeved 08/19/2002 9
DP-6) Repair History 2C10 2Cll 2C12 TSH Circs TSH Axial TSC Axial Freespan Axial Support Axial Support Wear Preventative U-bend Volumetric Total Repairs SG 88/89 SG 88/89 SG 88/89 08/19/2002 Cause 58 34 66 26
-47
-30 36 23 36 38
-34
-17 1
0 0
0
-0 A0 8
7 4
9
-6
-7 15 13 15 8
-23
-13 18 12 11 22
-14
-23 1
8 0
4
-?
0 0
0 0
-0
-0 0
5 0
2
~0
-2 137 102 132 109
-124
~92 10
DP-7) New Inspection Findings Discuss, in general, the new inspection findings
- During the 2C12 inspection, no damage mechanisms that were new to SONGS-2 were detected
- All mechanisms were previously detected and included in the degradation assessment and the operational assessment.
08/19/2002 11
DP-8) In-situ Pressure Testing
"* Utilizing latest EPRI and CEOG guidelines for candidate selection and testing
"* All tubes meeting criteria are tested
"* Have in-situ pressure tested 74 tubes at SONGS during seven prior inspections
- One tube in SG89 selected based on EPRI screening criteria
- Tubes in SG88 still under review 08/19/2002 12
TUBE AND EDDY CURRENT INFORMATION IN-SITU TESTRESULTS TUBE INFORMATION PLUSPOINT DATA Max.PDA GPM @ GPM @ GPM @ NOPD PRESURE REGION ROW COL LOCATION LENGTH VOLTS Depth DeApt ORIENTATION NOPD MSLB POST MSLB 3xNOPD Depth SONGS-2 IN SITU PRESSURE TEST LIST S/G 89 Jun-2002 08/19/2002.........
.13 TUBE AND EDDY CURRENT INFORMATION IN-SITU TESTRESULTS "TUBEINFORMATION PLUS POINT DATA Max.
PDA GPM @ GPM @ GPM @ NOPD PRESURE ROW COL LOCATION LENGTH VOLTS Depth Depth ORIENTATION NOPD MSLB POST MSLB 3xNOPD
% Depth EGGCRATE 13 119 061+018 018 0.24 71%
WA OD Axial-I 1
165R U DBHI+9 91 t NA N/A NIA N/A DATA QUALIlY BEND 113
DP-9) Tube Pull Plans Describe tube pull plans and preliminary results No tube pulls are planned based on the inspection results 08/19/2002 14
DP-10) Assessment of Tube Integrity From Previous Cycle Fourth application of multi-cycle, fully probabilistic(Monte Carlo) methods to Operational Assessment for SONGS Unit 2 in accordance with EPRI Tube Integrity Assessment Guidelines Results for 2C12 in good agreement with OA projections Expect to pass Condition Monitoring performance criteria 08/19/2002 15
DP-11) Assessment of Tube Integrity for Next Cycle Plan to continue use of multi-cycle, fully probabilistic(Monte Carlo) methods for Operational Assessment for SONGS Unit 2 in accordance with EPRI Tube Integrity Assessment Guidelines 08/19/2002 16
DP-12) 2C 12 Milestone Schedule Open breakers Primary manways off Begin ECT End ECT Insitu Begin repairs End repairs Primary manways on Close breakers 08/19/2002 17 5/20 5/23 5/24 6/5 6/5 6/5 6/11 6/17 6/22
DP-13) IP2 Lessons Learned
"* Actions taken in response to identifying a new degradation mechanism No new mechanism identified this outage
"* Actions taken to ensure data noise levels are acceptable Continue to use HF probe in U-bend region (2nd time)
Reviewed EPRI data set vs. SONGS tubing
"* Data quality issues and need for criteria to address data quality EPRI Rev 6 addressing SONGS participating 08/19/2002 18