Closeout of IE Bulletin 80-17: Failure of 76 of 185 Control Rods to Fully Insert during a Scram at a BWR (Boiling Water Reactor).

摘要

Documentation is provided in the report for the closeout of IE Bulletin 80-17 on the subject of safety-related failures of control rods to insert fully at boiling water reactors (BWRs). Closeout is based on the implementation and verification of numerous actions required for compliance with the initial bulletin and five supplements. Evaluation of utility responses and NRC/Region inspection reports indicates that the bulletin is closed for all of the 23 operating BWRs to which it was issued for action. The main reason for incomplete insertion of control rods was found to be retention of a significant amount of undetected water in the scram discharge volume (SDV). The bulletin and its supplements were forwarded for information only to all BWRs with a construction permit.