Abstract: A test apparatus for testing objects such as tubing is disclosed. The apparatus includes a rotatively fixed transducer and a rotating lens, wherein the transducer receives an input signal and converts it into an emitted wave energy, the lens focuses the emitted wave energy onto the tubing and focuses reflected wave energy from the tubing back onto the transducer, and the transducer receives the reflected wave energy and converts it into an output signal. The transducer can be provided on one support shell and the lens can be provided on another support shell. One of the support shells can then be positioned within the other support shell. The apparatus is useful for performing dimensional tests and longitudinal and circumferential flaw tests on tubing.

Abstract: An ultrasonic inspection system for composite materials capable of detecting flaws near the surface of the inspected part which flaws are normally masked by strong reflections from the part surface. An electronic signal representative of the strong surface echo is stored in memory and subtracted in a differential amplifier from the entire test piece echo representative signal in time relationship which effects cancellation of the signal representative of the strong surface echo thereby allowing weaker echo representative signals from defects near the surface to the detected.

Abstract: An ultrasonic transducer for generating an apodized beam of ultrasonic energy. A piezoelectric crystal element mounted in a housing generates on ultrasonic signal when electrically energized. A tungsten-epoxy layer mounted on the outer surface of the piezoelectric crystal element has a greater thickness at the periphery of the element than at the center, thus yielding an outwardly concave surface. The tungsten-epoxy layer provides a more uniform beam pattern.