Novel design of an effective pneumatic magnetostrictive patch transducer based on the ultrasonic guided wave for application of fast pipe health inspection

Abstract

Pipelines are widely used to transport water, oil, and gas. Severe corrosion of pipes can cause leakage of natural gas and result in an explosion or even more severe disasters. Magnetostrictive sensors based on ultrasonic guided waves have been validated as feasible for non-destructive testing of pipes with advantages of long-range inspection, high signal to noise ratio, with high testing efficiency. Using a patch made from a highly magnetostrictive material dramatically enhances the performance of these sensors; however, mounting this patch of smart material on a pipe requires using strong epoxy glue. Plus, applying the glue on the pipe and waiting for it to dry is time-consuming. After completing the test, leaving the pipe’s smart material could be hazardous and initiate electrochemical corrosion. Thus, smart material must be removed after the test. Nonetheless, it is complicated to remove smart material from the pipe’s surface after the glue dries. Considering such complications, as a solution to this problem, in this paper, the novel design of the pneumatic magnetostrictive patch transducer (PMPT) is proposed that benefits from the advantages of the patch in the magnetostrictive sensor but also eliminates such drawbacks. The performance of PMPT was validated by theoretical analysis and experimental investigation. The flexible, fast feature and portable configuration of the proposed PMPT make it easy to be applied on in-service pipes in different diameters with corrosion surfaces or coating.