Elcometer CG60DL Operating Instructions Manual page 43

Material being
Mode
measured
High penetration PULSE-ECHO
plastics and (P-E)
castings
Corrosion and pit PULSE-ECHO
detection in steel (P-E)
and cast materials
Material thickness ECHO-ECHO
measured through (E-E)
a coating
Transducer type
required
Cast iron - 1MHz to 5MHz
transducer.
Cast aluminium - 10MHz
transducer.
Plastics typically require
lower frequency
transducers depending on
the thickness and make-
up of the material.
Typically a 5MHz
transducer or higher is
required.
Special high damped
transducers are required;
typically the 3.5MHz,
5MHz, and 7.5MHz hi
damped transducers.
Notes
Larger diameters offer greater
penetration power because of the
crystal size, for difficult to measure
materials.
Use lower frequencies for greater
penetration and use higher
frequencies for better resolution.
These transducers are suitable for
use in both pulse-echo and echo-
echo modes. This enables you to
measure overall material thickness
using the Echo-echo mode, and then
switch to pit detection mode (Pulse-
echo) without changing transducers.
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