High-temperature ultrasonic thickness monitoring for pipe thinning in a flow-accelerated corrosion proof test facility

In order to monitor the pipe thinning caused by flow-accelerated corrosion (FAC) that occurs in coolant piping systems, a shear horizontal ultrasonic pitch-catch waveguide technique was developed for accurate pipe wall thickness monitoring. A clamping device for dry coupling contact between the end of the waveguide and pipe surface was designed and fabricated. A computer program for multichannel on-line monitoring of the pipe thickness at high temperature was also developed. Both a fourchannel buffer rod pulse-echo type and a shear horizontal ultrasonic waveguide type for hightemperature thickness monitoring system were successfully installed to the test section of the FAC proof test facility. The overall measurement error can be estimated as ± 10 mm during a cycle from room temperature to 200 C. © 2017 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).