Short range guided wave testing (SRGWT) is an application of guided ultrasonic sound waves using special types of probes. When the guided waves hit the discontinuities, the mode converted sound is reflected back and received by the transducer.
The major benefit of this technique is that it can be used to detect corrosion on plates and pipes that are inaccessible due to support structures, braces, brackets, saddles, legs, under insulations or other types of obstructions in the way of the region of interest. Another application is steel structures coated or surrounded by concrete.