Results from a trainable UT instrument - ALN 4060

The ALN 4060 Flaw Discriminator is a Z-80 microprocessor based ultrasonic flaw detector/discriminator which is operator trainable on up to three classes of reflectors. It can be applied to any testing situations where normal pulse-echo ultrasonics are used. Received ultrasonic RF waveforms are digitized (at operator selectable rates of up to 160 MHz) before processing and thereafter all internal operations and displays, as well as operator interfaces, are performed in digital mode. The system can be trained to recognize and discriminate between reflectors and can be used in analyses to recognize and classify reflectors by their waveform signatures. In this paper a summary is presented of the evaluation results and the operational experiences that were obtained by the Electrical Power Research Institute nondestructive examination centre in the application of the ALN 4060 to the problem of inspection of intergranular stress corrosion cracks in stainless steel pipes of boiling water reactors. (U.K.)