Couplants And Ultrasonic Testing: How It Works
It is part of the engineering-geeky language. So don’t worry if you have no idea what couplant means, or what ultrasonic testing is all about. We’re here to explain.
Understanding Ultrasonic Testing
Ultrasonic testing is performed on a variety of surfaces with the goal of identifying flaws in the materials. Although the most popular use of UT is on steel and metal alloys, often times the procedure is also applied on wood or concrete (but the efficacy of the test decreases significantly).
The best part about UT is that it allows testing of various materials without damaging them. It is also known as being a form of non-destructive testing.
What is a Couplant?
As the name subtly suggests, a couplant is a substance which connects the testing machine to the material to be tested. Most often the couplant is a kind of special oil. The testing machine is connected to an ultrasound transducer (very similar to sonars), which in its turn is put over the object to be inspected.
Perhaps the biggest advantage of UT is that it does not need to be performed in a special environment. For example, a technician can test various materials at a construction site, or on the field. So the materials which need to be tested do not need to be transported to a special place.
The role of the couplant is quite important during testing. The oily substance increases the performance and accuracy of the testing process. How? It reduces the losses in the ultrasonic wave energy. Losses occur due to surface inequalities, but the couplant eliminates these separations.
Advantages of UT and couplant
- – Even the smallest flaws can be detected because of the procedure’s high sensitivity
- – Portable
- – Great accuracy
- – Highly automated
