Ultrasonic Testing

Ultrasonic Testing is a Nondestructive Testing (NDT) method but it is used in various application areas, such as aerospace, automotive and transportation sectors. It is used for the inspection of metals, components, assemblies and composite structures. The process of Ultrasonic Testing involves introducing ultrasonic pulse-waves into the testing object to identify internal defects or to distinguish materials.

The frequency range of the ultrasonic pulse-waves is somewhere between 0.1-15 MHz. Ultrasonic Testing helps to determine the thickness of the object and check things like pipework corrosion. When Ultrasonic testing is done on steel and other metals and alloys high frequency waves are penetrated into the object. In case of concrete, wood and composites less resolution frequency waves are launched into the object.

Ultrasonic Testing – Working Explained

An Ultrasonic Testing system is used for the inspection procedure. The system comprises of certain functional units like pulser/receiver, transducer, and display devices.

·         Pulser/Receiver: It produce high voltage electrical pulses

·         Transducer: It produce high frequency ultrasonic energy

·         Display Devices: Reflects signal strength

The high voltage electrical pulses produced by pulser/receiver are driven to the transducer which in turn generates high frequency ultrasonic energy. This energy wave propagates through the test object in the form of waves. If there is some obstacle in the wave path like a crack then some part of the energy is reflected back. The reflected energy shows that there is a flaw in the surface of the test object.  The transducer transforms the reflected wave signal into electrical signal and displays it on the screen of the display device. Imperfections or other conditions in the space between the transmitter and receiver reduces the time of transmission of the signal and reveal the presence of defects.

Advantages Ultrasonic Testing

·         Ultrasonic testing makes detection of the deep rooted flaws easy due high frequency waves that penetrate into the testing object.

·         Ultrasonic testing also allows to spot flaws that are extremely small and otherwise not visible due to the high sensitivity of ultrasonic pulse-waves.

·         Ultrasonic testing requires access to only one surface to detect the flaws and transmit the results.

·         Ultrasonic testing produces extremely accurate results in comparison to the other nondestructive methods.

·         Ultrasonic testing helps to determine the in-depth internal flaws with easy and also identify thickness of parts with parallel surfaces.

·         Ultrasonic testing helps to estimate the size, orientation, shape and nature of defects as well.

·         Ultrasonic testing is a highly automated operation and is not affected by the surrounding equipment and materials in the area.