Abstract: A system for detecting and quantifying changes in the stress-strain state of a ferrous structure includes an exciter coil system positioned to generate an AC magnetic field that couples into the ferrous structure. A detector apparatus is positioned relative to the exciter to detect an eddy current magnetic field resulting from the AC magnetic field generated by the exciter coil system. An analyzer compares the eddy current magnetic field parameters detected by the detector apparatus with the direct AC magnetic field transmitted by the exciter coil system and correlates changes in the parameters of the eddy current magnetic field with the stress-strain on the ferrous structure.

Abstract: A centralizer for centrally locating measuring/testing equipment within the interior of a pipeline while traveling through the pipeline includes a first flange structure and a second flange structure nominally spaced from the first flange structure along the direction of travel of the centralizer. A plurality of radially outwardly curved loops extending between the first and second flange structures to form curved arches that define an outwardly convex outer surface. One or more ridges, or a single or a plurality of wheels, extending along the loops to project outwardly of the outer surfaces of the arches to extend above the remainder of the outer surface of the arches to bear against the interior of the pipeline.

Abstract: A system for detecting and quantifying changes in the stress-strain state of a ferrous structure includes an exciter coil system is positioned to generate an AC magnetic field that couples into the ferrous structure. A detector apparatus is positioned relative to the excited to detect an eddy current magnetic field resulting from the AC magnetic field generated by the exciter coil system. An analyzer compares the eddy current magnetic field parameters detected by the detector apparatus with the direct AC magnetic field transmitted by the exciter coil system and correlates changes in the parameters of the eddy current magnetic field with the stress-strain on the ferrous structure.

Abstract: A device is taught for inspecting the integrity of water distribution pipelines. The device is constructed of housing units, for housing inspection circuitry. The housing units are connected by flexible connectors which permit the units to move out of axial alignment to pass bends. In some embodiments, communication ports are provided between the units. As such, the device is able to negotiate bends and pass through openings of reduced size in the pipeline. The device can be used with various inspection technologies including remote field eddy current inspection technology. A method for inspecting the integrity of a water pipeline system is disclosed wherein water hydrants can be used to access the system.

Abstract: A method and apparatus for determining position size and shape of defects in a bundle of heat exchanger tubes are described. An AC current exciter coil is placed in one tube and a detector coil is placed in an adjacent tube. This configuration of exciter and detector coils reduces the blind spot effect caused by interference by tube support plates and allows the inspection multiple or finned heat exchanger tubing.