PIPELINE TOOL WITH COMPOSITE MAGNETIC FIELD FOR INLINE INSPECTION

Embodiments of an inline inspection ("ILI") tool (10) of this disclosure include a plurality of composite field systems (20) arranged circumferentially about the body of the ILI tool, each composite field system including multiple magnetic circuits (60) to produce a composite or resultant angled field © relative to the target, along with a sensor array or circuit (40) configured for magnetic flux leakage ("MFL") or magnetostrictive electro-magnetic acoustic transducers ("EMAT") implementations. In embodiments, the pole magnets (61) of the magnetic circuits are oriented in the axial direction of the tool body rather than in the direction of the resultant angled field. The same is true of the sensors (43). This composite field system approach provides options to design geometries that were not previously possible in prior art single-circuit helical MFL designs and EMAT designs.