Development of Tools for Measurement of Inner Shell Deformation of HANARO Reactor

It was estimated by an analysis method thai the inner shell of HANARO reactor will be deformed due to pressure, loads, creep and growth during reactor operation. To confirm the analysis validity and safe operation of reactor, we developed tools to remotely measure the straightness of the inner shell located 12m below the pool top. The performance and the accuracy of the measurement tools have been verified through tests using a dummy inner shell and steel straight edge. The accuracy of the measurement shows very good results with a maximum error of 0.06mm by steel straight edge. The technical experiences described in this paper will be a good reference not only for the operation and maintenance of HANARO but also for the next performance of the measurement in the future.