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© 2014 Proceq SA
2. Tutorial
The Zonotip / Zonotip
+
is designed to measure the thicknesses of ferrous and non-ferrous metals
as well as products made of plastics and other materials with a low ultrasonic attenuation. It meas-
ures the double traverse of an ultrasonic pulse through the object under test from one surface to
the other (see figure 1). This value is then converted into the product thickness value.
Transducer
Object under test
E1
E2
t
E1
E2
En
t0
2 x t0
n x t0
h
2
t0
c
h
Thickness
⋅
=
, c: speed of sound
Figure 1: Determining the thickness of an object by means of ultrasound pulse echo technique
The probe has a sharp radiation directivity and ultrasound receiving pattern, therefore, the product
thickness is determined directly under the converter installation place. If the material surface op-
posite to the one on which the probe is installed, has cavities, the US pulses will be reflected from
them, and the thickness is determined as the shortest distance from the external surface to these
cavities.
The Zonolink Software, included in the package, allows downloading the data measured by the
Zonotip / Zonotip
+
using any PC. Communication with the computer is provided through a USB
port.
Practical Advice for Measuring
To receive the maximal measurement accuracy, make sure that the probe, the calibration sample
and the test object have roughly the same temperature. If the measured velocity of the material
differs from the actual velocity, revise the velocity manually or perform a calibration.
The measurement accuracy directly depends on the accuracy of the velocity setting. For a precise
measurement, take a sample of the same material as the test object and set the velocity according
to it. For this procedure, use the same US converter as for the actual measurement. If possible, use
a plane-parallel sample with smooth surface for the test measurement.
