Surface flaw detection device for hot ingots - has ultrasonic test head providing Rayleigh waves of wavelength of twelve millimetres at given twenty-six degrees angle to ingot edges.

摘要

The device uses a checking head passed across the surface of the hot ingot at a constant distance from its surface parallel to its smaller side edges (11). The checking head has a pivoted ultrasonic transducer generating Rayleigh waves propagated in a direction at 26 degrees to the ingot edges. Pref. the Rayleigh waves have a wavelength of 12 mm, the checking head protected from high temp. and wear by a ceramic plate of aluminium oxide with a thickness of 0.6 mm on the underside of the ultrasonic transducer. The checking head may be mounted on a carriage transported relative to the surface of the ingot via rollers. USE - For checking surface of hot ingot at temp. of 500 degrees C. or more.