Visualization of Internal Defect of a Pipe Using Mechanoluminescent Sensor

Abstract

A defect in a pressurized pipe was visualized by using mechanoluminescent (ML) sensor. In the present work, the hoop strain distribution on the outer surface of a defective pipe was obtained by ML intensity measurement and strain gage measurement. Additionally, a FEM calculation was also performed and compared with the experimental results. The hoop strain distribution obtained from the ML intensity agreed well with that obtained from the strain gage measurement and the FEM calculation. It was found that the hoop strain on the defective pipe had maximum and minimum values around the defect and the maximum hoop strain increased with deepening the defect. These results indicate that the location and depth of the defect in a pipe can be estimated by using the ML sensor.