Possibility of detecting wall thickness loss using a PZT based structural health monitoring method for metal based pipeline facilities

Wall thinning effect for pipeline related facilities are one of the major issues when maintaining the structural integrity of facilities. Degradation of pipe by corrosion from the outer environment or the erosion from the products flowing within the pipe can reduce the wall thickness, weakening the structure. In this study, an attempt using the electromechanical impedance (EMI) method for detecting the wall thickness reduction is investigated. The main part of the study consists of analyzing how the resonance frequency range shifts as the wall thickness is reduced. The fact that a resonance frequency can either increase or decrease depending on how the property of a total system changes was taken into an account in this study. Since the EMI method heavily relies on signature variations, selecting a suitable frequency range was vital for detecting the reduction in wall thickness. The results from the investigation show a possibility of using the EMI method for detecting wall thickness reduction of metal structures.