Guided wave phased‐array focusing techniques have been studied and applied in the long‐range guided wave inspection of industrial pipelines. Advantages include longer inspection distance, greater wave penetration power and higher detection sensitivity. For reasons of protection, safety and thermal efficiency, a large percentage of pipes are coated and/or encased and buried underground. A phased‐array focusing study for guided waves is now considered on pipelines with viscoelastic coatings. In this paper, longitudinal guided wave focusing as well as axisymmetric wave propagation is studied in a bare pipe and a pipe with a viscoelastic coating. A finite element model is studied. First, an investigation on whether the coating has an affect on the axisymmetric guided wave propagation is reported. Based on the result of a single channel, phased array focusing with 8‐channel segments is studied. This study provides a very useful tool and guidance for the analysis and examination of guided wave focusing in a real field pipeline under various coating and environmental conditions.

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