ULTRASONIC SENSOR, APPARATUS AND METHOD FOR MEASUREMENT OF WALL THICKNESS

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic sensor which enhances the detection accuracy in the inspection of corrosion and a reduction in a thickness generated at a specimen. SOLUTION: The ultrasonic sensor is provided with a first probe 3 which transmits and receives ultrasonic waves from the surface of a coating film 2 on a tank baseplate T; and a second probe 4 which is installed in such a way that the angle of incidence of the ultrasonic waves with reference to the tank baseplate T becomes smaller than that of the first probe 3, and which transmits and receives ultrasonic waves from the surface of the coating film 2 at a tank baseplate T. The reception timing of reflected waves from the side of the tank baseplate T is delayed relatively at the second probe 4 with reference to the first probe 3, and the wall thickness of the tank baseplate T is calculated on the basis of reflected waves from the first probe 3 and the second probe 4 obtained by its delay.