Electromagnetic methods of defect detection

Probability of Detection Model for Pipeline Inspection

“…Magnetic flux leakage (MFL) method of NDT [2] is the primary technique in natural gas transrnission pipeline inspection. The principle of the MFL method can be demonstrated by Figure 2 [3], where the existence of a metal-loss defect causes some flux lines to "leak out" into the air due to local saturation of the flux density in the vicinity of the flaw [4].…”

Numerical modeling of probe velocity effects for electromagnetic NDE

“…Basic electromagnetic NDE phenomena can be fully described by the classical Maxwell equations [84,85]. Magnetostatic NDE such as magnetic boundaries are already taken into account.…”

“…However, if a major objective is to gain a fuller understanding of the underlying physics from the associated field distributions, finite element solutions are very useful in that they give full field solutions [85]. Perhaps the best choice may be the hybrid finite element-boundary integral methods [109][110][111] which exploit the advantages of both methods.…”

“…In the active magnetic flux leakage test [9][10][11][12], a test specimen is magnetized by passing an appropriate value of DC current through it, thus setting up a magnetic field governed by the Maxwell-Ampere law.…”

Imaging and inverse problems of electromagnetic nondestructive evaluation

“…Note: often one transducer performs the functions of both the input and the output transducer. Various types of energy are used in NDE including ultrasonic [2][3], electromagnetic [1][2][4][5], and thermal [6][7]. The governing physical phenomena of a particular inspection depends directly on the type of NDE energy which is used.…”