Investigation of an on-line pipe wall defect monitoring sensor

This paper presents development of a defect monitoring sensor using electromagnetic acoustic transducer (EMAT). The present study investigates the possibility of the defect monitoring using a new EMAT structure. The current EMAT was unsuitable for monitoring because of the large sensor area, and also it was necessary to have a mechanical scanning. Therefore, it was developed a new EMAT, smaller in size which does not need a mechanical scanning. The new EMAT was manufactured for a trial purpose. Based on the result of the performance test, it was found out that the new EMAT is able to monitor a defect and also to monitor both a thin and thick piping wall.