Probe approach for DGS sizing

An ultrasonic detection assembly for detecting a characteristic in a test object having a cylindrical peripheral surface, the ultrasonic detection assembly comprising:

• a phased array probe configured to be positioned in proximity to the cylindrical peripheral surface of the test object, the phased array probe including a plurality of transducer elements extending linearly across a distal end of the phased array probe and forming a circular inspection surface of the phased array probe, each transducer element of the plurality of transducer elements being laterally spaced apart and separated from adjacent transducer elements by a gap formed within the inspection surface, wherein at least one of the plurality of transducer elements extend in a linear manner fully across the circular inspection surface, wherein each transducer element is operatively configured to emit a respective beam into the test object in a time-delayed manner relative to an adjacent transducer element so as to provide a pattern of constructive interference;
• a beam adjustment structure for providing cylindrical contact between the phased array probe and the cylindrical peripheral surface of the test object, the beam adjustment structure directly coupled to the inspection surface of the phased array probe;
• and
• a controller operatively connected to the phased array probe for causing each transducer to emit the respective beam into the test object.