ENS 41335

v t e 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.

ENS 41335 +/-
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
v • d • e

v t e Emergency Notification System
Framatome Anp with 10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation
WEEKMONTHYEAR2005-01-14T08:00:00 [Table view]
[ENS list for Framatome Anp]

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