On-Machine, in-Process, Ultrasonic Gauging and Flaw Detection

An ultrasonic system has been assembled to provide real time thickness gauging on a lathe during a cutting operation. The same ultrasonic system provides flaw detection so that NDE of the part being machined is simultaneously accomplished. A key feature for good gauging performance is that the ultrasonic apparatus is configured to minimize sensitivity of the time interval measurements, used for the gauging operations, to variations in echo amplitude over a 30 dB dynamic range. Thickness data or flaw echo data can be displayed in a pseudo colored image format in near real time. The goal for this research is to make thickness measurements with an accuracy of better than 0.0005 in. over a minimum range of 0.1 to 1.0 in.