Dakota Ultrasonics
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surface of the test material does not have to be as flat in order to obtain good
measurements.
Dual element delay line transducers are have a usable range of 0.025” and up,
depending on the material, frequency, and diameter.
A limitation of dual element delay-line transducers is the V shaped sound path.
Because the sound travels from one element to another, the time versus thickness
relationship is non-linear. Therefore, a correction table in the instruments software is
used to compensate for this error.
Dual Element Transducer showing V-path of signal
Searching for small defects
Dual element delay line transducers are especially useful in searching for small
defects. As a result, this configuration is commonly used for corrosion inspections.
The dual element style transducer will find wall deterioration, pits, cracks, and any
porosity pockets during tank and pipeline inspections.
