7
After this, you should
„scan“
the bar.
To do so, you lay the measurement head on different
spots to exclude inclusions of foreign material.
In case of a fake, the value of the thickness can
differ significantly.
Measurement 2: Examination of UNKNOWN sound speeds
There are several situations where the sound speed is not exactly known. Some bars are made
of alloys, others of uncommon materials. The sound speeds for those are not listed in our
overviews and the online data sources sometimes differ significantly from each other. In this
case, you have to choose the procedure that is explained as follows.
If you know that the material (for example on the exterior edge) is not pervaded by the normally
centrally situated foreign metal bars, you can establish the speed of sound here. The
measurement head is laid on spot in question with the ultrasound gel. In this case, it is
irrelevant, which speed of sound is selected.
Summary of Contents for BARSCREENSENSOR
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