Patent ID: 8742752
Filing Date: 2014-06-03
Classification: G01N

Abstract:
1. A method of eddy current testing for flaws in a tube, comprising: passing an eddy current probe through the tube and obtaining eddy current data for a first number of positions along the tube; analyzing the eddy current data to generate background noise data for a second number of positions along the tube, the background noise data comprising a plurality of noise data values wherein each of the noise data values is associated with a respective one of the second number of positions; analyzing the eddy current data to generate extracted data for a third number of positions along the tube; and determining whether a flaw of a particular category is present in the tube based on a set of one or more of rules applied to at least a portion of the extracted data, wherein at least one of the rules uses a particular part of the extracted data and employs a changing threshold that changes with position along the tube and that, for any selected position along the tube, is a function of a particular one of the noise data values that is associated with the selected position along the tube.