Echo Ultrasonic is a right couplant for many Ultrasonic Testing (UT) and Non Destructive Testing (NDT) applications that requires a specialty UT couplant. It is used for difficult inspections that require high acoustic impedance, shear wave, reduced surface noise, extreme temperature range.
A high impedance couplant typically has an acoustic impedance above 3.5 M Rayls. Water based couplants typically have acoustic impedances between 1.5 and 1.8 M Rayls depending on the Glycerin content (0% glycerin at 1.5 M Rayls, 12% glycerin at 1.8 M Rayls, 100% glycerin at 2.4 M Rayls).
The advantage of a high impedance couplant is that more of the acoustic energy is transmitted between the transducer (or delay line) and test object and less is reflected and scattered at the surface of the test object. This is particularly important when:
The test object surface is very rough (porous cast iron, scale, rough grinding).
The contact area for the delay line or transducer is small (pencil point probes measuring pit depths).
Materials such as concrete which are high impedance, scatter acoustic energy and often have a rough surface.
There are currently two options for water-soluble, high impedance couplants:
Z+MV- a medium viscosity Glycerin based couplant (which has an operating range of 0 to 200°F; however, its viscosity increases quickly with temperature below 45°F. Z+fluid– does not contain Glycerin and maintains a fluid viscosity down to sub-zero temperatures.
Russell Fraser Sales NDT | Inspection, NDT & Testing Equipment
Russell Fraser Sales Pty Ltd supplies inspection, NDT and testing equipment to Engineering, Construction, NDT, Aerospace, Marine and Diving industries primarily throughout Australia, New Zealand and ...