ENS Event | |
|---|---|
08:00 Jan 14, 2005 | |
| Title | Part 21 Report |
| Event Description | The following information was provided by Framatome ANP
The turbine generator load rejection with failure of the turbine bypass valves to open event (LRNB) is a potentially limiting anticipated operational occurrence (AOO) considered in establishing the MCPR operating limit and confirming that the linear heat generation rate (LHGR) limits are adequate. Framatome ANP analyses for the LRNB event assume that the load rejection will initiate a fast closure of the turbine control valves (TCV) at all power levels. Some plants have indicated that the fast closure of the TCV is not initiated below a plant specific power level. The fast closure of the TCV initiates a scram and minimizes turbine over speed. If a fast closure of the TCV does not occur, the TCV will close at a slower rate, scram will be delayed, and the turbine will overspend. This may increase the severity of the event. The turbine overspend may result in an increase in recirculation pump speed that will also increase the severity of the event. The affected plants LaSalle Unit 2 Cycle 10 and Browns Ferry Unit 3 Cycle 12 have been notified. A set of revised operating limits, which are appropriate for the conditions when a fast closure of the TCV does not occur, have been provided to the affected plants. |
| Where | |
|---|---|
| Framatome Anp Richland, Washington (NRC Region 4) | |
| Organization: | Framatome Anp |
| Reporting | |
| 10 CFR 21.21 | |
| Time - Person (Reporting Time:+6.17 h0.257 days <br />0.0367 weeks <br />0.00845 months <br />) | |
| Opened: | Jerald Holm 14:10 Jan 14, 2005 |
| NRC Officer: | Bill Gott |
| Last Updated: | Jan 14, 2005 |
| 41335 - NRC Website | |
Framatome Anp with 10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation | |
WEEKMONTHYEARENS 413352005-01-14T08:00:00014 January 2005 08:00:00
[Table view]10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation Part 21 Report 2005-01-14T08:00:00 | |