WHAT IS ULTRASONIC INSPECTION?
The Ultrasonic Testing is a method of Non Destructive Inspection which is based on the phenomenon of the reflection of acoustic waves when they encounter discontinuities in a material. The wave will be reflected back to its source if the discontinuity is in a normal position relative to the incident beam. SCI has a variety of different techniques to carry out the Ultrasonic tests:
Conventional Ultrasound test equipment works on the principle of sending a pulsed beam of high-frequency ultrasound from a handheld transducer or probe, which is placed on the surface of the object to be tested.
In this manual method the inspecting engineer is directly responsible for the proper application of the inspection procedures, both in handling the probe and in the interpretation of the data.
SCI has also spent more than a decade developing its own Automated Ultrasonic Inspection Equipment, whether it be conventional techniques based on pulse-echo, or the more innovative systems such as Phased Array or TOFD.
The Automatic Ultrasonic Testing (AUT) with the pulse-echo method is performed by dividing up the welding areas and using a specific probe for each zone. This method involves using a varying number of feelers for each zone, depending on the profile and thickness of the weld. The probes, mounted on a carriage moving circumferentially around the welding, maintain a constant distance from the center line.
Today, the use of Phased Array technology, has enabled considerable progress in method and execution in this area. The Phased Array system is based on using probes with multiple crystals. By selecting a particular set of probes and applying appropriate delays, different angles can be obtained. But recent advances means that the procedure can now be carried out by a single probe.
Automatic Ultrasounds provide some significant advantages such as::