Coupling Agents - sauter TO-EE Instruction Manual

10.6 Coupling agent
All ultrasonic applications require a medium to couple the sound from the transducer
to the specimen. Normally a liquid with high viscosity is used as medium. The
propagation in air of the sound used for ultrasonic thickness measurement is
ineffective.
A wide range of coupling agents can be used for ultrasonic measurement. Propylene
glycol is suitable for most applications. Glycerine is recommended for difficult
applications where maximum transmission of sonic energy is required. However, on
some metals, glycerine can promote corrosion by absorbing water and may therefore
be undesirable. Other suitable coupling agents for measurements at normal
temperatures are water, various oils and greases, gels and silicone fluids.
Measurements at elevated temperatures require specially formulated heat-resistant
couplants.
When measuring ultrasonic thickness, the instrument may use the second echo
instead of the first echo from the back of the material to be measured by operating in
standard pulse-echo mode. This can result in a thickness measurement that has a
thickness value twice as large as it really is. It is the sole responsibility of the user of
the instrument to use the instrument correctly and to detect such effects.
Note:
The CE Declaration of Conformity is available under the following link:
https://www.kern-sohn.com/shop/de/DOWNLOADS/
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