Ultrasonic Measurement of Simulated Lack of Penetration in Stainless Steel Girth Welds: A Feasibility Study

摘要

An algorithm for the measurement of lack of penetration in a stainless steel girth weld has been developed and implemented on a computerized ultrasonic test bed facility. This nondestructive inspection technique incorporates signal processing and frequency analysis to measure lack of penetration. The method is semi-automatic: the operator positions the search probe over the weld, the computer acquires and processes the reflected signals, the operator windows out the significant echoes and the computer calculates the depth of lack of penetration. The algorithm has been tested using weld samples with simulated lack of penetrations varying from .090 inch to full penetration. The depth of these EDM slots were ultrasonically measured to an accuracy consistent with the machining process. (ERA citation 07:047715)