Ut Coverage of Nozzle Inner Radius including Amplitudes

This paper reports progress in on-going studies to validate UT modeling of nozzle inner radius examinations. In a previous paper [1] it was shown that geometric modeling and raytracing in the Windows-based software WARay3D predicts the geometry and location of search units needed to detect known defects in a nozzle mock-up. The present paper describes the addition of beam forming [2] and flaw response [3] modeling to W ARay3D and compares predicted amplitudes with those measured in the same nozzle mock-up. Beam forming and flaw response are formulated analytically and make use ofthe output of geometric ray tracing, which includes flaw detection and metal path leading to a computationally efficient hybrid approach. Correlation between predicted and measured amplitude drop is presented for ultrasonic signals from comer trap inspection of innerradius flaws. Reference signals are obtained from calibration tests using comer trap at a machined flat surface.