
Why Survey?
The special survey, also called the class-renewal survey, is performed every five years. The survey verifies that the structure, systems, equipment, and essential auxiliary machinery are in satisfactory condition and don’t have any high-risk flaws or damage.
Ultrasonic Thickness Testing
As part of the special survey, ATS performs thickness testing for vessel components. One of the biggest threats to sea vessels is corrosion – such as the reaction between the vessel’s metallic materials and salt-water to form rust. Corrosion can slowly eat away at the metal and cause material loss, resulting in decreased thickness. To accurately measure thickness, our NDT experts use ultrasonic thickness testing (UTT). In the UTT method, high-frequency sound waves are sent directly into the test material through a probe, which then reflect back. Our technicians analyze the properties of the signal to obtain a thickness reading.