Characterize the pipeline damage caused by corrosion through the use of ultrasonic guided waves

Pipeline is one of the most important assets in many cities. However, in-service pipeline is prone to defects due to aging, external impacts, or hazardous operating environment. It is of prime importance to apply an efficient inspection technique so that the severity of damage caused by corrosion can be determined prior to a fatal rupture of pipeline. An early warning generated from an accurate estimation of severity can encourage the performance of proper remedy for minimizing the scope of damage to pipelines. In this paper, a presentation is given to an advanced inspection method based on ultrasonic guided waves. This method has already shown great potentials in non-destructive testing of material and structures in many fields. The advantages and difficulties involved in the pipeline inspection using ultrasonic guided waves have been identified. Since corrosion is a major type of damage caused to in-service pipelines, we have introduced a novel method for detecting the existence of corrosion as well as its severity. The method analyzes the captured signal reflected from the emitted longitudinal guided waves, separates the overlapped signal and then identifies the extent of corrosion. Although the experiments were conducted using artificial corrosion, the results proved that qualitative measurement for determining the severity of corrosion is feasible. Combined with guided waves, our method can provide qualitative information related to the area, the depth, the location of corrosion etc., through the analysis of reflected signal generated by the interactions of emitted guided waves with corrosion.