ML093210544
| ML093210544 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 11/17/2009 |
| From: | Entergy Operations |
| To: | Plant Licensing Branch IV |
| Kalyanam N, NRR/DLPM, 415-1480 | |
| Shared Package | |
| ML093210496 | List: |
| References | |
| Download: ML093210544 (4) | |
Text
Steam Generator Secondary Side Inspections Fall 2009 Refuel 16 Outage Preliminary Results Page 1 of 4 NOECP-257 Steam Generator Secondary Side Inspections Inspect following areas of SGs for loose parts and evidence of flow accelerated corrosion.
x area below the steam separator can deck x
area around tube supports x
area around feedring x
area above the steam separator can deck x
area above dryer deck Steam Generator #1 Upper Inspection Issues Discovered 3/4 feedwater distribution box vent fell off (CR-WF3-2009-06504) 3/4 4 J-nozzles with pin hole in welds (CR-WF3-2009-06622)
Actions Taken 3/4 Retrieved distribution box vent assembly. The J-tube portion of the distribution box vent had significant flow accelerated corrosion. The T-fitting portion of the distribution box vent had little to no corrosion.
3/4 UT 21 of 40 of the 3-1/2 inch diameter J-nozzles (including all with pin holes)
Minor wear (nominal thickness 0.318 inch) with the lowest measured UT reading of 0.212 inch.
Measured wall size ranges from 67% to 135% of original wall; areas of degradation are not significantly different from the nominal pipe wall. It can be concluded that the J-nozzles will be able to perform its intended function for the next cycle of operation per Westinghouse Letter LTR-SGDA-09-189 3/4 UT and boroscope distribution box around vent - showed no signs of significant erosion 3/4 UT Ring Header between J-nozzles
Minor wear on the 12 inch Ring Header (nominal thickness = 0.4 inch). The lowest measured UT reading is 0.335 inch.
Wall size ranges from 83% to 109% of original wall; areas of degradation are not significantly different from the nominal pipe wall. It can be concluded that the ring header will be able to perform its intended function for the next cycle of operation per Westinghouse Letter LTR-SGDA-09-189 3/4 100% external visual and boroscope interior weld areas of 21 of 40 J-nozzles
4 J-nozzles with pin hole in welds. The holes seem to be the result of the welding process. The holes are in the weld material and are generally not biased to either the nozzle or the ring header.
Per visual inspection the welds are acceptable with respect to Westinghouse letter LTR-SGDA-09-188, which calculated the minimum required weld is
Steam Generator Secondary Side Inspections Fall 2009 Refuel 16 Outage Preliminary Results Page 2 of 4 0.017 inch over 270 degrees of the circumference. The minimum rigid base material was determined to be 0.020 inches.
No signs of significant erosion 3/4 verification pull test of vent weld remnant to ensure not potential loose part
No loose parts identified
Good weld fusion to distribution box Resolutions 9 Westinghouse letter LTR-SGDA-09-189 provides the acceptability of SG operation 9 EC-18652 use-as-is evaluation is being prepared Steam Generator #1 SG31 Failed Distribution Box Vent
Steam Generator Secondary Side Inspections Fall 2009 Refuel 16 Outage Preliminary Results Page 3 of 4 SG31 J-Tube Nozzle Pin Hole Steam Generator #2 Upper Inspection Issues Discovered 3/4 pin hole found in weld of distribution box vent elbow (CR-WF3-2009-06629)
Actions Taken 3/4 UT distribution box and vent / also boroscope inside of distribution box including back of vent weld connection
Thin area of vent line (nominal thickness = 0.300 inch). The lowest measured UT reading is 0.086 inch.
Small hole observed in weld of vent elbow Westinghouse letter LTR-SGDA-09-188 Rev 1 calculated the minimum required weld material to be 0.015 inch over 270 degrees of the circumference. The minimum rigid base material was determined to be 0.017 inches. Therefore, this is acceptable since both the hole in the vent elbow weld and the area of thin wall meet the acceptance criteria.
3/4 100% visual inspection of J-nozzles
No areas of degradation observed Resolutions 9 Westinghouse letter LTR-SGDA-09-189 provides the acceptability of SG operation 9 EC-18652 use-as-is evaluation is being prepared
Steam Generator Secondary Side Inspections Fall 2009 Refuel 16 Outage Preliminary Results Page 4 of 4 SG32 Distribution Box Vent