Abstract: A digital radiography imaging system for acquiring digital images of an object, and a method for transforming digital images into an absolute thickness map characterizing the object under inspection. The system includes a radiation source for directing radiation through a desired region of the object, and a radiation detector having a plurality of sensing elements for detecting radiation passing through the object. Numerical data generated from each sensing element is calibrated, for example by correcting for variations in radiation paths between the source and detector, by correcting for variations in the spatial frequency response (MTF) of the detector, by correcting for variations in the geometric profile of the object under inspection, and by correcting for material contained in and/or around the object. The calibrated data is processed in order to generate and display an absolute thickness map of the object.

Abstract: A configuration flexible computer-controlled ultrasonic diagnostic test equipment arrangement for examining large turbine rotors incorporates improved ultrasonic signal "pulser-receiver" circuitry that is used to drive one or more an ultrasonic transducers and to receive and amplify ultrasonic returns from a specimen under test. The improved pulser-receiver circuitry comprises both an ultrasonic pulse generating circuit and an associated ultrasonic return signal linear amplification circuit. The pulse generating circuitry and the ultrasonic return signal amplification circuitry are modular and functionally independent of each other and, consequently, may be used together in the testing system or as stand-alone instrumentation. Overall ultrasonic diagnostic system flexibility is significantly enhanced by providing improved pulser-receiver circuitry with digitally driveable computer control inputs in addition to manual controls to enable selecting initial parameters and transducer position settings.

Abstract: A method and apparatus for the ultrasonic inspection of acoustically "noisy" specimens, such as those having intrinsically coarse grain structure (e.g., turbine rotor parts made of superalloy compositions) employs several types of ultrasonic diagnostic measurement techniques, including at least: "Pitch-Catch" analysis and "Pulse-Echo Axial Long-Wave" analysis. When a Pitch-Catch technique is utilized, a "through-transmitted" sound wave is acquired for each specimen tested and used as a calibration standard to normalize ultrasonic inspection test data for that specimen prior to any automated defect/flaw detection and sizing processing. The through transmitted sound wave is also used to equate the amplitude of "indications" (i.e., significant detected ultrasonic reflections) to that of a standardized theoretical reflector of known size (e.g.