Digital instruments for the enhancement of manual ultrasonic testing

The term `digital NDT equipment´ generally, at present, encompasses two broad categories. At one end of the spectrum lie complex instrumentation systems which incorporate a high degree of automation, or some form of relatively sophisticated signal processing, or both. At the other end of the spectrum, a new generation of digital instruments is emerging, in which conventional manual flaw detectors are being enhanced by the addition of digital control circuitry to the familiar analog functions normally offered. The paper addresses two digital instrumentation developments which lie between these two extremes. They are aimed at the small-scale ultrasonic inspection involving manual application of a few probes. As well as introducing control over the way the inspection is performed, they also automatically record the data generated and generate a record of material coverage, thus significantly increasing the reliability of inspection. One of the aims of the second development is to maintain, in addition, a record of the route followed when analysing the data