INTEGRITY CONFIRMING METHOD FOR SPENT NUCLEAR FUEL STORAGE VESSEL THROUGH VIBRATION WAVE MEASUREMENT

摘要

PROBLEM TO BE SOLVED: To confirm sealing integrity which does not require large scale works by monitoring internal pressure of a spent fuel storage vessel from outside. SOLUTION: A vibration measurement sensor is attached to the spent nuclear fuel storage vessel and is vibrated at a vibration point. From the waveform obtained by the vibration measurement sensor, natural vibration frequency is obtained through frequency analysis. The change in the internal pressure caused, when airtightness is lost, is captured as the change in the vibration frequency, and the internal pressure is monitored from the vessel outside, so that sealing integrity is confirmed.