Guided waves can be used in pipe inspection over long distances. Presented in this paper is a beam focusing technique to improve the $S∕N$ ratio of the reflection from a tiny defect. Focusing is accomplished by using nonaxisymmetric waveforms and subsequent time delayed superposition at a specific point in a pipe. A semianalytical finite element method is used to present wave structure in the pipe. Focusing potential is also studied with various modes and frequencies.

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