Metallic loose-parts detection and characterization

A theoretical and experimental research program was conducted to provide basic information and guidelines for a comprehensive loose-parts monitoring system suitable for industrial use. This work is an attempt to bring together theoretical work on impact and elastic wave propagation with the current needs of loose parts characterization in an industrial environment. The pertinent work developed by many on the theory of impact and wave propagation over the past century is discussed. The experimental work for impact location and characterization was performed using modern transient signal analysis techniques. The experiments were performed and techniques developed first on a simple flat plate. The methods were further improved using the Experimental Gas Cooled Reactor (EGCR) structure at Oak Ridge National Laboratory (ORNL) as the test bed. Several impact location techniques were developed and explored extensively. Their effectiveness and accuracy are demonstrated on the flat plate and the EGCR pressure vessel. Furthermore, various impact characterization techniques were developed utilizing the time dependent RMS and the relative power spectrum of the impact signals. The overall performance of the impact location and characterization methods developed proved both useful and effective under noisefree and simulated background noise conditions