Ultrasonic Inspection of Thick Hot Steel Products.

A system that has been developed for ultrasonic inspection of thick hot steel products is described. The system uses a special type of longitudinal-wave transducer with a separate transmitter and receiver, armoured and thermally protected. The system has been tried on thicknesses of up to 600 mm and temperatures of up to 1200 degree C. The results of the measurements show that the system is sufficiently sensitive at high temperatures to detect a 5 mm diameter artificial defect at a depth of 500 mm with two backwall echoes.