Magnetostatic NDE methods are used extensively in industry to inspect a wide variety of ferromagnetic materials. The interpretation of signals derived from such methods is, however, fraught with several interesting challenges. First, the information contained in the signal is inherently low due to the static nature of the process. Second, the signal is vulnerable to the effects of a number of test and material parameters, such as the specimen magnetization characteristics and lift-off. This paper describes systematic approaches both for compensating the effects of such parameters as well as methods for full characterization of the defect. Examples showing the effectiveness of the approach for gas transmission pipeline inspection are presented. Work described in the paper was supported by the Gas Research Institute, Chicago.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 3, pages 1631 - 1634 Publisher:Ashgate Publishing Company