ULTRASONIC THICKNESS TESTING MEASUREMENT (UTTM)
Method used to inspect the metal thickness.
Thickness measuring is to monitor corrosion, erosion, and damage. Works by precisely measuring how long it takes for a sound pulse that has been generated by a small probe called an ultrasonic transducer to travel through a test piece and reflect back from the inside surface or far wall.
Widely used for:
Ship hulls
Piping pressure vessels
Structural steel
Plastic tubing
Fibreglass
Etc.