ENS Event | |
|---|---|
15:46 May 6, 2004 | |
| Title | Reactor Vessel Head Nozzle Weld Area Flaw |
| Event Description | During performance of NDE examinations of the Point Beach Nuclear Plant (PBNP) Unit 1 reactor pressure vessel (RPV) head required by the First Revised NRC Order (EA-03-009), flaw indications were identified on Nozzle 26. The ultrasonic examination (UT) signal for nozzle 26 identified flaw indications in the J-groove weld area that extend into the CRDM tube base material.
A dye-penetrant (PT) examination of the nozzle 26 CRDM J-groove material was also performed. The PT exams showed minor surface indications that required further evaluation. Following minor excavation of the weld surface, additional examinations of the J-groove surface were performed. The results of these exams indicated the existence of flaws in the weld that do not meet accepted flaw evaluation guidance. Based upon preliminary analysis, it is expected that these indications would not be found acceptable under ASME standards. Therefore, this condition represents degradation of a principal safety barrier reportable under 10 CFR 50.72(b)(3)(ii)(A). PBNP Unit 1 Nozzle 26 is planned to be repaired prior to placing the RPV Head back into service. The condition was determined to be reportable at 1046 CDT on May 6, 2004. The licensee has notified the Resident Inspectors. |
| Where | |
|---|---|
Point Beach  Wisconsin (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | |
| LER: | 05000266/LER-2004-001 |
| Time - Person (Reporting Time:+-2.27 h-0.0946 days <br />-0.0135 weeks <br />-0.00311 months <br />) | |
| Opened: | Jim Fouse 13:30 May 6, 2004 |
| NRC Officer: | Mike Ripley |
| Last Updated: | May 6, 2004 |
| 40728 - NRC Website
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