Abstract: A method for pipeline inspection is provided. The method includes carrying out an inspection run in which a pipeline inspection apparatus travels inside a pipeline, wherein sensors on the apparatus are configured to conduct an in-line inspection of wall material along a length of the pipeline. The method includes initiating a first inspection mode to produce a primary inspection data set, wherein the first inspection mode comprises an inspection of the pipeline wall material upstream and downstream of a location of a dented region in the pipeline, selectively initiating a second inspection mode to produce a secondary inspection data set, wherein the second inspection mode includes an inspection of the pipeline wall material in the dented region in the length of the pipeline, and combining the primary and the secondary inspection data sets to provide a direct assessment for the presence of cracks and/or corrosion in wall material along the pipeline.

Abstract: A magnetizer for a pipeline inspection tool. The magnetizer comprises a ferromagnetic base member, a pair of driving magnets mounted at spatially separate locations on the base member and a flux enhancing magnet mounted on the base member adjacent to one or both of the driving magnets. The directions of magnetization of the pair of driving magnets extend in opposite senses to each other, towards and away from the base member respectively to create a magnetic circuit that includes a flux path between the driving magnets which passes through the base member. The flux enhancing magnet has a direction of magnetization substantially aligned with the direction of magnetic flux on the flux path, the flux enhancing magnet being magnetically coupled to the adjacent driving magnets to drive flux around the magnetic circuit and thereby enhance the magnitude of a magnetic field exhibited by the magnetic circuit outside the magnetizer.

Abstract: A method for pipeline inspection is provided comprising carrying out an inspection run in which a pipeline inspection apparatus travels inside a pipeline, wherein sensors on the apparatus are configured to conduct an in-line inspection of wall material along a length of the pipeline. The method further comprises initiating a first inspection mode to produce a primary inspection data set, wherein the first inspection mode comprises an inspection of the pipeline wall material upstream and downstream of a location of a dented region in the pipeline, selectively initiating a second inspection mode to produce a secondary inspection data set, wherein the second inspection mode comprises an inspection of the pipeline wall material in the dented region in the length of the pipeline, and combining the primary and the secondary inspection data sets to provide a direct assessment for the presence of cracks and/or corrosion in wall material along the pipeline.

Abstract: In an in-line pipe inspection tool, sensors for inspecting the pipe are mounted on sensor blocks moveable relative to the body of the tool. However, when the sensor blocks move radially to conform to different pipe diameters, the circumferential distances between the sensors changes. To ameliorate the effect of this, the sensor blocks have a shape such that one axial edge of each sensor block circumferentially overlaps the opposite edge of an adjacent sensor block. With such an arrangement, when the sensor block are operating at minimum diameter, part of one sensor block will overlap an adjacent block, in the circumferential direction. As the diameter of the pipeline in which the pig is used increases, the degree of overlap will reduce, and may even reduce to zero, but there will still be no overall axial gaps between the sensor blocks. Thus, by suitable shaping of the sensor blocks the tool can be used with a wide range of pipe diameters.

Abstract: An inspection sensor module for an in-line pipe inspection tool has a support for mounting the module on the tool, a finger pivotally attached at one end to the support and pivotally attached at the other end to a sensor block carrying one or more inspection sensors. A first leaf spring extends from the support to the finger to bias the finger outwardly, and a second leaf spring extends from the support to the carrier to bias the sensor block. Biasing sensors are mounted on the leading and trailing edges of the first leaf spring to detect movement of the first leaf spring corresponding to movement of the inspection sensors towards or away from the support.

Abstract: An in-line pipe inspection tool has one or more inspection platforms (28, 30) which are connected to an elongate wheeled trolley by link arms (20 to 26). The trolley unit (10, 12) has drive means for driving the point of connection of the first link arm (20, 22) to the trolley (10) relative to the point of connection of the second link arm (24, 26) to the trolley (12), thereby to move the inspection platforms (28, 30) in a direction perpendicular to the direction of elongation of the trolley (10, 12). Thus the inspection platforms (28, 30) are movable which is relative to the trolley (10, 12) to permit the tool to be adapted to pipelines of different diameters. Moreover, the platforms (28, 30) preferably have permanent magnets which contain a rotatable magnet. The rotatable magnet permits the net magnetic field generated by the platform to be varied.

Abstract: Ultrasonic pipeline inspection apparatus which utilizes two different wave modes (e.g. a horizontally polarized shear mode and a symmetric Lamb wave mode) to discriminate different defect types by comparing corresponding signals collected from defects. EMATs may detect the signals. The detected amplitudes of the collected signals from both wave modes are compared to calculate a ratio, which may be compared with a distribution of ratio values for known defects to evaluate the type of defect detected. The apparatus may be a sensor module mountable on a pipeline vehicle and having a plurality of sensors distributed around its periphery.

Abstract: Ultrasonic pipeline inspection apparatus which utilises two different wave modes (e.g. a horizontally polarised shear mode and a symmetric Lamb wave mode) to discriminate different defect types by comparing corresponding signals collected from defects. EMATs may detect the signals. The detected amplitudes of the collected signals from both wave modes are compared to calculate a ratio, which may be compared with a distribution of ratio values for known defects to evaluate the type of defect detected. The apparatus may be a sensor module mountable on a pipeline vehicle and having a plurality of sensors distributed around its periphery.

Abstract: An in-line pipe inspection tool has one or more inspection platforms (28, 30) which are connected to an elongate wheeled trolley by link arms (20 to 26). The trolley unit (10, 12) has drive means for driving the point of connection of the first link arm (20, 22) to the trolley (10) relative to the point of connection of the second link arm (24, 26) to the trolley (12), thereby to move the inspection platforms (28, 30) in a direction perpendicular to the direction of elongation of the trolley (10, 12). Thus the inspection platforms (28, 30) are movable which is relative to the trolley (10, 12) to permit the tool to be adapted to pipelines of different diameters. Moreover, the platforms (28, 30) preferably have permanent magnets which contain a rotatable magnet. The rotatable magnet permits the net magnetic field generated by the platform to be varied.

Abstract: An in-line pipe inspection tool has one or more inspection platforms (28, 30) which are connected to an elongate wheeled trolley by link arms (20 to 26). The trolley unit (10, 12) has drive means for driving the point of connection of the first link arm (20, 22) to the trolley (10) relative to the point of connection of the second link arm (24, 26) to the trolley (12), thereby to move the inspection platforms (28, 30) in a direction perpendicular to the direction of elongation of the trolley (10, 12). Thus the inspection platforms (28, 30) are movable which is relative to the trolley (10, 12) to permit the tool to be adapted to pipelines of different diameters. Moreover, the platforms (28, 30) preferably have permanent magnets which contain a rotatable magnet. The rotatable magnet permits the net magnetic field generated by the platform to be varied.

Abstract: In an in-line pipe inspection tool, sensors for inspecting the pipe are mounted on sensor blocks moveable relative to the body of the tool. However, when the sensor blocks move radially to conform to different pipe diameters, the circumferential distances between the sensors changes. To ameliorate the effect of this, the sensor blocks have a shape such that one axial edge of each sensor block circumferentially overlaps the opposite edge of an adjacent sensor block. With such an arrangement, when the sensor block are operating at minimum diameter, part of one sensor block will overlap an adjacent block, in the circumferential direction. As the diameter of the pipeline in which the pig is used increases, the degree of overlap will reduce, and may even reduce to zero, but there will still be no overall axial gaps between the sensor blocks. Thus, by suitable shaping of the sensor blocks the tool can be used with a wide range of pipe diameters.

Abstract: An in-line pipe inspection tool has a sensor carrier carrying a plurality of sensor for monitoring the pipe. In order to permit the sensor carrier and hence the sensors, to conform to changes in the diameter of the pipe being inspected, the sensor carrier is a part cylindrical body which is resiliently flexible. However, to stop one part of the sensor carrier twisting torsionally relative to another part, a bracing unit is fixed to one part the sensor carrier and engages another part of the sensor carrier to resist said torsional twisting.

Abstract: An electromagnetic acoustic transducer (12, 24) has one or a plurality of magnets for applying a DEC magnetic field to a material (4, 25) under test, and an electrical coil (2, 23) supplied by an alternating current source for, providing an AC magnetic flux within the material under test. A wear plate (16, 26) engages with an slides along the surface of the material under test. The wear plate (16, 26) is of electrically conductive ferromagnetic material and has apertures (17, 31) therein. Thus, both the DC field and the ACT flux can penetrate the material under test and create ultrasonic vibration of that material.

Abstract: An electromagnetic acoustic transducer for exciting ultrasound in a ferromagnetic material under test (2), includes a magnetic unit (6) arranged to be moved relative to the material under test (2) to magnetize a surface layer of the material, and an electrical winding (8) supplied by an alternating current source, the magnetic unit (6) and the electric winding (8), in use, being applied in sequence to the material under test (2) whereby the electrical winding (8) is positioned adjacent the material subsequent to magnetization thereof by the magnetic unit (8), the alternating magnetic flux created by the winding (8) interacting with the remanent magnetization of the material to create ultrasonic vibration of the material.

Abstract: A pipeline pig includes a central body member, a plurality of circumferentially spaced return path elements surrounding said body member and each extending axially relative to the body member, each return path element including a pair of axially spaced magnets from each of which projects a metallic bristle set, and means for connecting the return path elements to the body member whereby the free ends of the bristles, in use, resiliently engage the inner wall of the pipeline, the connecting means comprising a first carrier member mounted on, to be axially slidable relative to, the front extent of the body member and resiliently urged towards the rear of the body member, a second carrier member mounted on, to be axially slidable relative to, the rear extent of the body member and resiliently urged towards the front of the body member, and, for each return path element, a front link pivotally interconnecting the front of the return path element and the first carrier member, and a rear link pivotally interconnect

Abstract: A pipeline pig comprises a body and at least one flexible annular outwardly extending seal on and around the body for sealingly contacting a pipeline interior wall under differential fluid pressure whereby to propel the pig along the pipeline. The pig also comprises a fluid bypass duct arrangement extending through the body and resilient frictional bristles on and extending from the body adapted to contact the pipeline interior wall and exert a drag on the pig. An adjustable bypass flow control unit is provided which is adapted to regulate fluid flow through the duct arrangement and thus the speed of the pig.