Checkline TI-007DLX, Руководство по эксплуатации

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4.0 SELECTING THE MEASUREMENT MODE
4.1 Which mode & transducer do I use for my application?
High penetration plastics and castings
High penetration plastics and castings The most common mode for these types of
applications is pulse-echo. Thicker cast iron and plastics applications will generally
require lower frequencies depending on the material type and thickness. Frequencies
from 2.25MHz to 10MHz are common. Larger diameters offer greater penetration power
based on the size of the crystal.
Thin Materials & Tough Access Areas
The high frequency delay line transducers are suitable when measuring thinner
consistent materials that pass sound easily, such as steel, aluminum, titanium, etc. They
offer temperature compensation with a suitable range up to 1” depending on the delay
line used. Replaceable cone tip options are also useful for difficult access areas and
diameters.
Thru Paint & Coatings
It’s common that users will be faced with applications where the material will be coated
with some type of protective paint or other epoxy based material. Since the velocity
of the coating is approximately 3 times slower than that of steel, pulse-echo mode will
produce an error if not removed. However, echo-echo mode can be used with either
delay line or contact style transducers to eliminate the error from the coating, and
measure only the base material. High damped or high frequency transducers are most
suitable for echo-echo measurement mode.
Plastics
Thin plastics are best suited using the delay line transducer with either the acrylic delay
tip in echo-echo or interface-echo modes. If the plastic measured is similar in velocity
to the acrylic tip and not measuring adequately, the replaceable graphite tip and plastics
mode will serve as the best option. Thicker plastics will generally require a lower
frequency contact style transducer for additional penetration. Increasing the diameter of
the transducer will also offer greater output.
High temperature
High temperature applications will require a special delay line material that isn’t as
absorptive of temperature.