Abstract: An apparatus and methods for determining the position of an elongate structure. A number of magnetic field sensors arranged at fixed spacing, each sensor being arranged to sense a magnetic field of a remote structure induced by the Earth's magnetic field in at least two orthogonal directions. In use, the magnetic field sensors are arranged remotely of an elongate structure having a longitudinal axis, such that the magnetic field sensors are spaced in a lateral direction relative to said longitudinal axis. An angular spacing for the magnetic field sensors about the longitudinal axis is determined according to the magnetic field readings in the two orthogonal directions and a distance between one or more of said magnetic field sensors and said elongate structure is determined based on said angular spacing determination.

Abstract: An apparatus and methods for determining the position of an elongate structure. A number of magnetic field sensors arranged at fixed spacing, each sensor being arranged to sense a magnetic field of a remote structure induced by the Earth's magnetic field in at least two orthogonal directions. In use, the magnetic field sensors are arranged remotely of an elongate structure having a longitudinal axis, such that the magnetic field sensors are spaced in a lateral direction relative to said longitudinal axis. An angular spacing for the magnetic field sensors about the longitudinal axis is determined according to the magnetic field readings in the two orthogonal directions and a distance between one or more of said magnetic field sensors and said elongate structure is determined based on said angular spacing determination.

Abstract: The invention concerns structural integrity assessment apparatus for determining stress concentration zones in a structure, such as a pipeline. The apparatus allows particularly to detect defects in buried pipelines using magnetometric surveying where anomalies in the magnetic field around the pipelines are detected. The appar-atus has a plurality of triaxial magnetic field sensors, each sensor being arranged to measure magnetic field components in a plurality of directions. A support is provided to maintain said sensors in a predetermined relative spacing and orientation. The support is moveable relative to a structure under assessment in use and may be portable. Three or more magnetic field sensors are provided which may be arranged in a linear, two-dimensional or three-dimensional array. The ap-paratus may include position determining means, such as a global positioning system (GPS), so that stress concentration zones can be located on the structure.

Abstract: The invention concerns structural integrity assessment apparatus for determining stress concentration zones in a structure, such as a pipeline. The apparatus allows particularly to detect defects in buried pipelines using magnetometric surveying where anomalies in the magnetic field around the pipelines are detected. The apparatus has a plurality of triaxial magnetic field sensors, each sensor being arranged to measure magnetic field components in a plurality of directions. A support is provided to maintain said sensors in a predetermined relative spacing and orientation. The support is moveable relative to a structure under assessment in use and may be portable. Three or more magnetic field sensors are provided which may be arranged in a linear, two-dimensional or three-dimensional array. The apparatus may include position determining means, such as a global positioning system (GPS), so that stress concentration zones can be located on the structure.

Abstract: The invention concerns a structural integrity assessment system and method for determining stress concentration zones in a structure, such as a pipeline. The invention comprises a magnetic field sensor array arranged to be moved relative to the structure in a known direction. A controller is provided for recording one or more magnetic field readings taken by the magnetic field sensor array at different locations in the direction of movement thereof. A processor is arranged to identify one or more feature within said values, said feature being indicative of a region of reduced structural integrity in the structure. The processor also receives a data input for a further parameter corresponding to the location of the sensor array and compares the feature with the further parameter in order to verify that said feature corresponds to a region of reduced structural integrity for the structure.

Abstract: The invention concerns a structural integrity assessment system and method for determining stress concentration zones in a structure, such as a pipeline. The invention comprises a magnetic field sensor array arranged to be moved relative to the structure in a known direction. A controller is provided for recording one or more magnetic field readings taken by the magnetic field sensor array at different locations in the direction of movement thereof. A processor is arranged to identify one or more feature within said values, said feature being indicative of a region of reduced structural integrity in the structure. The processor also receives a data input for a further parameter corresponding to the location of the sensor array and compares the feature with the further parameter in order to verify that said feature corresponds to a region of reduced structural integrity for the structure.

Abstract: The invention concerns structural integrity assessment apparatus for determining stress concentration zones in a structure, such as a pipeline. The apparatus allows particularly to detect defects in buried pipelines using magnetometric surveying where anomalies in the magnetic field around the pipelines are detected. The apparatus has a plurality of triaxial magnetic field sensors, each sensor being arranged to measure magnetic field components in a plurality of directions. A support is provided to maintain said sensors in a predetermined relative spacing and orientation. The support is moveable relative to a structure under assessment in use and may be portable. Three or more magnetic field sensors are provided which may be arranged in a linear, two-dimensional or three-dimensional array. The apparatus may include position determining means, such as a global positioning system (GPS), so that stress concentration zones can be located on the structure.