Abstract: There is obtained a wire-rope flaw detector capable of realizing a high signal-to-noise ratio even in the case where only one detection coil is disposed.

Abstract: A method of testing for defects in the bottom of an above ground storage tank, the tank bottom having a lip extending outwardly from the tank wall around the circumference of the tank. A special magnetostrictive sensor is designed to be placed on this lip. The sensor is placed over a strip of magnetostrictive material, which generally conforms in length and width to the bottom of the probe, with a couplant being applied between the strip and the lip surface. The sensor is then operated in pulse echo mode to receive signals from defects in the bottom of the tank. It is incrementally moved around the circumference of the tank.

Abstract: A magnetic testing apparatus has a magnetizing device applying a rotating magnetic field to a material to be tested, a testing signal detecting device, and a signal processing device applying signal processing to the testing signal. The signal processing device has a first synchronous detecting device detecting a testing signal by using the first current as a reference signal, a second synchronous detecting device detecting an output signal of the first synchronous detecting device by using the second current as a reference signal to extract a candidate flaw signal, and a testing image display device displaying a testing image in which each of pixels has a gray level corresponding to an intensity of the candidate flaw signal at each of positions of the material to be tested, and a phase of the candidate flaw signal at each of the positions is capable of being identified.

Abstract: The device comprises a magnetization unit, which generates a constant magnetic field, to which the test specimen (12) is exposed so as to magnetize it. The magnetization unit and test specimen (12) carry out a relative motion to each other, thereby inducing eddy currents in the test specimen (12). The magnetization unit has at least one yoke (10) projecting in the direction of the relative motion. In addition to a probe (14), which is offset toward the back with respect to the magnetization unit in the direction of the relative motion and which is suited to detect damage based on the influence of the damage on the induced eddy current, the device comprises at least one further probe (16) between the yoke limbs of the magnetization unit.

Abstract: Digital ferromagnetic part inspection system and method use a magnetizer for magnetizing a ferromagnetic part to be inspected, wherein a defect in or near a surface of the ferromagnetic part causes an external magnetic field. A magnetic field sensing element is positioned near the ferromagnetic part for sensing the external magnetic field. An inspection module identifies the defect in or near the surface of the ferromagnetic part by interpreting data collected by the magnetic field sensing element in response to the magnetic field sensing element being placed near the ferromagnetic part.

Abstract: A method of assembling an eddy current probe for use in nondestructive testing of a sample is described. The method includes positioning at least one substantially planar spiral drive coil within the eddy current probe, such that the drive coil is at least one of adjacent to and at least partially within a flexible material. The method further includes coupling at least one unpackaged solid-state magnetic field sensor to the at least one drive coil.

Abstract: Identification of points of interest in a region of the surface of a part, by bringing a surface reference into intimate contact with the region is disclosed. The surface reference includes a thin film sufficiently flexible to conform to the region and tracks made of electrically conductive material. The passage of an eddy current probe over a track delivers a significant signal representative of the track. This representative signal corresponds to a point of interest thus identified in the region. Thus, it possible to optimize the path and the angular position of an eddy current probe scanning a region of a part to be tested.

Abstract: In detecting a flaw by generating an eddy current in a conductor, it is enabled to easily detect a flaw in the vicinity of a back surface of the conductor. An exciting device and a receiving device are held in the vicinity of a conductor, and an eddy current is generated in the conductor by a primary magnetic field generated by excitation, thereby generating a secondary magnetic field, the state of the magnetic field is detected by the receiving device. The exciting device includes a coil and an iron core. The coil has a first current line and a second current line in which an electric current flows in opposite directions. The iron core is gate-shaped in cross section and includes a first leg portion, a second leg portion, and a beam portion. The iron core is oriented such that an opening thereof on a side opposite to the beam portion faces the conductor. The first current line of the coil is disposed on an inner side of the two leg portions of the iron core.

Abstract: An embodiment disclosed herein is directed to a method of monitoring an electromagnetic shield effectiveness including transmitting a first electromagnetic field toward a first surface of an electromagnetic shield, detecting a second electromagnetic field transmitted from a second surface of the electromagnetic shield, generating a first signal corresponding to the second electromagnetic field and determining whether a defect exists at the electromagnetic shield by comparing the first signal to a predetermined threshold.

Abstract: An eddy current probe adapted for detecting cracks in material directly beneath a raised-head fastener is disclosed. The probe comprises an eddy current coil and a support for carrying the coil in an orientation suitable for introducing eddy currents into material directly beneath a raised-head fastener.

Abstract: An electromagnetic impedance sensor detects an object made of conducting material or soft magnetic material with contact-free. The sensor includes: a detection coil; and a detection circuit for supplying electricity to the coil and for measuring electromagnetic impedance change in the coil. The detection coil includes multiple coil portions provided by one wire. One coil portion has a side adjacent to a corresponding side of another coil portion. The side and the corresponding side extend along with a direction, and the side has a current flowing direction, which is the same as the corresponding side.

Abstract: In a method for detecting near-surface defects in a test sample consisting at least partly of a ferromagnetic material, a test volume of the test sample is magnetized and scanned for the detection of magnetic leakage fields caused by defects. The test volume is magnetized by means of a magnetic constant field and simultaneously by means of a magnetic alternating field superposed on the constant field. Leakage field test devices suitable for carrying out the method are described.

Abstract: A method of assembling an eddy current array probe to facilitate nondestructive testing of a sample is provided. The method includes positioning a plurality of differential side mount coils at least partially within a flexible material. The method also includes coupling the flexible material within a tip portion of the eddy current array probe, such that the flexible material has a contour that substantially conforms to a portion of a surface of the sample to be tested.

Abstract: A non-contact type transducer having a multi-loop coil that is used to perform a modal test or a nondestructive inspection on a plate member without contacting the plate member is disclosed. The transducer includes a multi-loop coil having two or more closed loop portions and disposed above and separate from a plate member; and a magnet having a neutral plane between north (N) and south (S) poles parallel to a surface of the plate member and functioning as a static magnetic field former, wherein the plate member is formed of a conductor, wherein an eddy current that flows on a surface of the plate member is generated by controlling a current that flows through the multi-loop coil, and Lorentz forces are applied in directions perpendicular to the surface of the plate member due to the eddy current and a magnetic field component parallel to the surface of the plate member of a static magnetic field formed by the static magnetic field former.

Abstract: An inspecting device including a detachable probe has a link structure, and thus a subject having various diameters is tested. In addition, since various probes are changeably used in a scanner housing, ultrasonic wave testing and eddy current testing are simultaneously performed.

Abstract: The present application discloses a magnetostrictive sensor (MsS) probe for guided-wave inspection of the entire length of a fuel rod. The probe includes a waveguide adapted to be clamped to a fuel rod, and an MsS adapted to generate guided waves into the waveguide such that the guided waves propagate down the waveguide into the fuel rod and back to the waveguide for detection by the MsS.

Abstract: An eddy current probe assembly suitable for inspecting a test object with longitudinal shape, being passed through the assembly in the object's axial direction during an inspection session, the probe assembly comprising multiple probe modules being disposed in a radial plane and with the modules partially overlaying on each other forming an iris structure encircling an inspection zone, wherein a movement in unison of each of the probe modules closer to or further away from the center of the inspection zone makes the inspection zone enlarged or contracted. Spring tension is applied on each of the probe modules so that constant life-off in maintained between the probe modules and the test surface. Array of eddy current elements for each probe module and multiple layers of probe modules can be employed to achieve complete coverage of the test surface. The radial cross-sectional shapes of the test objects can be of round or polygonal.

Abstract: Device for the non-destructive testing of parts of a turbomachine motor, comprising a longitudinal rod carrying at its distal end a longitudinal finger carrying a retractile or deployable flexible blade supporting an inspection probe, this blade being guided in axial translation on the finger between a retracted position in which it extends along the finger and an advanced or deployed position in which it extends in front of the finger.

Abstract: A flexible elongate structure, such as a flexible riser (10) for connecting oil and gas wells to floating production platforms, comprising at least one layer (20) of steel wires near the surface which extend at least partly along the length of the structure, can be monitored by inducing a magnetic field in the steel wires using an electromagnetic coil, and monitoring the magnetic flux density near the surface of the structure so as to detect if any wires have broken. Measurements are made at two different frequencies, the lower frequency giving an output dependent both on stresses and on the number of adjacent wires in the layer (20), and the higher frequency giving an output primarily dependent on the number of these wires. By comparing these two measurements a corrected output parameter (P) may be obtained that is indicative only of stress. A break in a wire can be expected to change the stress in that and adjacent wires.

Abstract: A magnetic flux generated by current excitation is allowed to pass through a part or an entire of a magnetic path of a leakage magnetic flux. A magnetic flux content due to the current excitation is temporally changed to change a leakage magnetic flux content interlinked with a detection coil so that an induced voltage is generated in the detection coil. Consequently, damage can be detected even in a case where there is no relative speed between a wire rope and a wire rope flaw detector. Further, a configuration of the magnetic path and the number of ampere turns of an exciting coil are set to be appropriate to prevent the magnetic flux generated by the current excitation from passing through the detection coil or to allow the magnetic fluxes offset each other. Thus, noise superimposition on the detection coil due to the current excitation can be prevented.

Abstract: A pipeline inspection tool has an even number “n” of spiraled pole magnets spaced equidistant apart and spanning the length of the tool. Each pole magnet, which preferably has a conformable upper surface, is rotated or spiraled about the tool body so that a second end of each pole magnet is offset a predetermined amount “?” relative to a first end of that same pole magnet. The amount of rotation ? applied to each of the pole magnets produces a magnetic field oblique to the central longitudinal axis of the tool body (and therefore the pipe) and one that covers 360° of the internal wall surface of the pipe. A helical-shaped array of magnetic flux sensors may be arranged about the tool body and substantially equidistant between adjacent pairs of pole magnets. The tool detects axially oriented, circumferentially oriented, and volumetric anomalies and allows for single pass inspection.

Abstract: A method of detecting defects using eddy currents is disclosed. The method comprises: exciting eddy currents in a test material using an eddy current probe driven by a drive signal; detecting induced eddy currents in the test material; converting the detected signal into integer values using an analog to digital converter; and adding or subtracting the generated integer values to or from each of two accumulators, or taking no action, so that one accumulator produces a value proportional to one component of the detected signal and the other produces a value proportional to another component of the detected signal and using these values to detect the presence of a defect.

Abstract: The invention concerns a system suited for carrying out eddy current measurements on components for nuclear reactors when these components are located in water. The system comprises a control unit, a measurement probe and a first cable suited to constitute at least a part of the connection between the control unit and the measurement probe. The system also comprises a switching unit, suited to be located in water and arranged to be connected with said first cable, and to be connected with the measurement probe. The switching unit has a switching device which can assume at least a first and a second state. In the first state, the first cable is connected with the measurement probe. In the second state, the first cable is not connected with the measurement probe. The invention also concerns the use of the system.

Abstract: A detection apparatus for an eddy current in a heat generating tube using a permeability measurement method, and a method using the apparatus are provided. In the detection apparatus, a bobbin type probe acquires detection information with respect to a magnetic flux change by a magnetic phase occurring in the heat generating tube using a coil which is wound in an axis direction of at least one yoke located in a perpendicular direction with a bobbin of the bobbin type probe, and a material having a corresponding magnetic phase and a circumferential defect, which is difficult to be detected by the bobbin type probe, are detected based on the detection information.

Abstract: A technique for determining properties of a bearing assembly in use involves using an eddy current probe for detecting changes in material density within a raceway of the bearing assembly. A field of detection of the eddy current probe enters the bearing raceway intermediate races that define the raceway, and as such the detection is of the bearing elements, and not deflections in a wall that defines the raceway.

Abstract: An in-line inspection tool is disclosed for inspecting the wall of a pipeline while traveling therethrough. The in-line inspection tool may include a transmitter, a signal generator, one or more receivers, and a decoder. The signal generator may generate a pseudorandom signal, generate an inspection signal, and drive the transmitter with a convolution of the pseudorandom signal and the inspection signal. The transmitter may transmit the convoluted signal to the wall of the pipeline. One or more receivers may receive from the wall of the pipeline a received signal comprising at least one of the convoluted signal and a reflection of the convoluted signal. The decoder may identify the inspection signal within the received signal by cross correlating the received signal and the pseudorandom signal.

Abstract: A method is shown for magnetostrictive testing of structures using magnetostrictive techniques. A torsional guided wave is generated in the structure either directly, or through a magnetostrictive strip dry coupled or bonded to the structure. A permanent magnetic field is created by either permanent magnets or DC current for a permanent bias in a bias direction in the magnetostrictive strip and/or structure. By pulsing the magnetic field with an AC current pulse, a torsional guided wave will flow through the structure in the same direction as the permanent bias. By saturating the permanent magnetic field, a maximum torsional guided wave is reflected from defects in the structure to given an improved signal to noise ratio.

Abstract: A segmented magnetostrictive patch array transducer capable of generating a high frequency shear wave in a structure such as a rod or a pipe, a structural fault diagnosing apparatus including the segmented magnetostrictive patch array transducer, and a method of operating the segmented magnetostrictive patch array transducer are shown. The segmented magnetostrictive patch array transducer includes a plurality of magnetostrictive patches attached along a circumference of a rod member; a plurality of insulators that are disposed on the magnetostrictive patches; a plurality of meander coils, each of the meander coils comprising a plurality of coil lines extending along the circumference direction of the rod member on each of the insulators, wherein a current flows through adjacent coil lines in opposite directions to one another; and a plurality of magnets that respectively form a magnetic field along the circumferential direction of the rod member on the magnetostrictive patches.

Abstract: In order to examine abnormality in shape of an outer circumference of a wire rope, the rope tester device includes a comb-shaped detection plate having a curved test edge portion extending along at least one portion of an outer circumference of a substantially circular sectional configuration of the wire rope and a testing recessed portion for receiving the wire rope in the vicinity of or in contact with the test edge portion, and a support device for rotatably supporting the detection plate in the vicinity of or in contact with the wire rope for permitting the rotation of the detection plate when the detection plate receives a force from an abnormal portion of the wire rope to relieve the force. A test string is disposed in an opening of the testing recessed portion for testing a surface that is not in the vicinity of or in contact with the test edge portion.

Abstract: An inspection device for inspecting tangential recesses in a rotor disk by means of eddy currents is disclosed. The device includes a probe containing a plurality of sensors arranged to acquire a plurality of data series during a scan stroke, and the probe is mounted on moving equipment that is slidable in a support that is provided with two positioning members for co-operating with recesses neighboring the recess for inspection.

Abstract: An eddy-current flaw detection device comprises a magnetic element group of which a specified number of magnetic elements are evenly spaced in each of at least two rows around the surface of a column shaped casing that can be inserted into a conductive pipe, with one row being located at a different position from the other row by ½ the even spacing in the row direction, and switching circuits for switching the magnetic elements in the respective row at time-division. The elements of one row function as magnetic field excitation elements, the elements of the other row function as magnetic field detection elements, and the eddy-current flaw detection device performs eddy-current flaw detection of the conductive pipe by detecting magnetic field excited by magnetic field excitation element by two magnetic field detection elements located at different positions from the magnetic field excitation elements by 3/2 the even spacing.

Abstract: A casing inspection device with magnets and a multi-component flux sensors. The multicomponent sensor enables better definition of the size of defects, particularly in the azimuthal direction.

Abstract: The invention provides an eddy current testing method for an internal finned pipe or tube which can securely detect a micro defect generated in a trough portion in an inner surface of the pipe or tube, even in the case that an inner surface shape of the internal finned pipe or tube is ununiform in a circumferential direction of the pipe or tube. The eddy current testing method in accordance with the invention detects a defect existing in a trough portion of the pipe or tube (P) by arranging a differential coil (2) constructed by a pair of coils (21, 22) having such a dimension as to be arranged within the trough portion of the pipe or tube (P) and coming away from each other in an axial direction (X) of the coil, within the trough portion of the pipe or tube (P) along a direction in which the trough portion of the pipe or tube (P) extends, and relatively moving the differential coil (2) in the direction in which the trough portion of the pipe or tube (P) extends.

Abstract: An apparatus and method are disclosed for detecting flaws in electrically conductive materials by observing properties of the back-EMF of the eddy current field generated by driving magnetic flux through the object to be examined. The input signal may include sweeps at several frequencies, and may do so at one time under the principle of wave superposition. The sectorial observations of eddy currents summations may be compared to a known datum for a defect free material, the presence of anomalies in eddy field back EMF divergence tending to provide an indication of an irregularity in the underlying eddy field, and hence in the underlying material itself. The portable unit may have a number of different configurations depending on the nature of the object to be examined, be it a flat or large radius plate, a flange, a rail, or some other structural element.

Abstract: Using eddy currents to inspect a hole that is possibly not rectilinear and/or of section that is not circular. The inspection device comprises a stick shaped and dimensioned to be capable of being engaged in said hole, at least one arm hinged to a support fastened to one end of the stick, an eddy current sensor being embedded in said arm, and resilient means for urging the arm outwards against the inside surface of the hole.

Abstract: There is obtained a wire-rope flaw detector capable of realizing a high signal-to-noise ratio even in the case where only one detection coil is disposed.

Abstract: Inconsistencies in a reinforced resin matrix part are detected using an inductive coupling probe connected with or part of a tuned resonant circuit. An alternating magnetic field produced by the probe is coupled to the part and produces eddy currents in the part. Inconsistencies in the part result in changes in the complex impedance and/or resonance of the circuit which are detected by a network analyzer.

Abstract: A method of eddy current testing without the need for lift-off compensation. Signal response features similar to those used in pulsed eddy current techniques are applied to conventional (harmonic) eddy current methods. The described method provides advantages in terms of data storage, since only two response parameters, the amplitude and phase, are sufficient to reconstruct any sinusoidal signal, therefore allowing for scanning of large surfaces.

Abstract: A sensor measures the interaction of an applied magnetic field to a sample surface that includes magnetic materials to determine whether the samples surface has been corroded. The sensor measures the magnetic force resulting from the interaction or the magnetic flux density to determine the content of magnetic material in localized regions of the sample surface. The sensor includes a cantilever beam with a strain gauge for measuring magnetic force. Alternatively, the sensor includes a magnetic flux density sensor to measure magnetic flux density.

Abstract: A device with separate emission/reception functions for making eddy current tests on an electrically conducting part comprising several emission rows (1-4) composed of emission windings (55), and several reception columns (a-h) each composed of reception windings (56) connected in series in at least one series, in which the emission windings associated with the reception windings in one series are powered by currents at different frequencies.

Abstract: An inspection system for detecting flaws on a moving metal (e.g., steel) bar coordinates the operation of an eddy current testing (ECT)-based flaw detection apparatus and an imaging-based flaw detection apparatus. The ECT-based flaw detection apparatus and the imaging-based flaw detection apparatus are disposed along a movement path in a predetermined relationship with each other, for example, as a predetermined fixed offset distance therebetween. A synchronizing mechanism synchronizes the output data streams from the two flaw detection apparatuses based on the predetermined relationship, so as to align the data streams as function of the axial position on the metal bar. A processing unit is configured to process the synchronized data streams for the detection of flaws, which are then also synchronized (axial position).

Abstract: A method of synthesizing nondestructive examination data of a component that combines data sets acquired at least two different frequencies. At least one of the data sets is interpolated or extrapolated to the equivalent of data acquired at one of the other frequencies employing a third, reference set of eddy current inspection data that is acquired at each of the inspection frequencies being combined.

Abstract: A wire rope flaw detector comprises a back yoke and excitation permanent magnets, which form a main magnetic path in a predetermined section of a wire rope in the axial direction; a magnetic path member arranged in the predetermined section to be magnetically insulated from the back yoke and the permanent magnets and making the leakage flux generated from a damaged part of wire rope detour to the outside of the wire rope; and a detection coil wound around the magnetic path member for detecting leakage flux. The amount of leakage flux can be increased by providing the magnetic path member and since the windable area of the detection coil is increased, the number of turns of detection coil can be increased.

Abstract: A method and apparatus in which at least two different test phases are performed on a test object, selected from: conventional eddy current testing, partial saturation eddy current testing, and ultrasonic testing. Measurement data sets are obtained from the at least two different test phases, with each measurement data set comprising measurement data corresponding to a plurality of test positions. The data sets are combined in a data processing means and the combined measurement data is processed to evaluate a damage condition of the test object. In a preferred embodiment, all of conventional eddy current testing, partial saturation eddy current testing, and ultrasonic testing are performed. The apparatus may be provided in two or more sub-assemblies, of which one may be an internal test tool and one may be an external tool. Alternatively, the apparatus may be capable of carrying out all three of the test phases.

Abstract: A sensor for detecting surface defects of a metal tube solves a problem of a conventional eddy current probe in that it is difficult to detect a crack in the circumferential direction of a metal tube. The sensor includes a plurality of coils wound at a predetermined inclined angle. The plurality of coils is inserted into the inside of a metal tube. Alternating current is applied to the coils to measure a change in impedance of the coils due to a change in an eddy current generated in the metal tube, thus detecting a surface defect of the metal tube.

Abstract: A method for non-contact measurement of a dimension and/or an electrical property in an electrically conducting object to be measured by using electromagnetic induction. An electromagnetic field is brought to penetrate through the object to be measured. A transmitter coil is place on one side of the object to be measured. A receiver coil is placed on the other side of the object to be measured. A magnetic field is generated in the transmitter coil. A sudden change is generated in the magnetic field generated in the transmitter coil from one level to another. The voltage induced in the receiver coil is detected. The period of time that elapses from the time of the change of the magnetic field in the transmitter coil up to the time when a voltage starts to be induced in the receiver coil is determined. The magnitude of the induced voltage is determined. The thickness and/or electrical conductivity of the object to be measured is calculated.

Abstract: Methods and apparatus are described for absolute electrical property measurement of materials. This is accomplished with magnetic and electric field based sensors and sensor array geometries that can be modeled accurately and with impedance instrumentation that permits accurate measurements of the in-phase and quadrature phase signal components. A dithering calibration method is also described which allows the measurement to account for background material noise variations. Methods are also described for accounting for noise factors in sensor design and selection of the optimal operating conditions which can minimize the error bounds for material property estimates. Example application of these methods to automated engine disk slot inspection and assessment of the mechanical condition of dielectric materials are presented.

Abstract: Any inspection object regardless of material can easily be inspected or discriminated with high accuracy and high sensitivity by being placed in a magnetic field generated by applying an alternating current to an exciting coil and detecting changes of voltage level and phase of electromotive force induced by a detection coil unit. The discrimination of the inspection object is performed on the basis of a DC voltage value with respect to a standard specimen and a phase differential voltage value with respect to a phase difference between the phase of a voltage signal from the induction coil and the phase of the exciting current to the exciting coil.

Abstract: The invention provides an eddy current testing method for an internal finned pipe or tube which can securely detect a micro defect generated in a trough portion in an inner surface of the pipe or tube, even in the case that an inner surface shape of the internal finned pipe or tube is ununiform in a circumferential direction of the pipe or tube. The eddy current testing method in accordance with the invention detects a defect existing in a trough portion of the pipe or tube (P) by arranging a differential coil (2) constructed by a pair of coils (21, 22) having such a dimension as to be arranged within the trough portion of the pipe or tube (P) and coming away from each other in an axial direction (X) of the coil, within the trough portion of the pipe or tube (P) along a direction in which the trough portion of the pipe or tube (P) extends, and relatively moving the differential coil (2) in the direction in which the trough portion of the pipe or tube (P) extends.

Abstract: The eddy current testing apparatus includes a probe having an eddy current testing sensor including a pair of eddy current testing coils. The apparatus also includes an eddy current testing flaw detector inputting detection signals from the eddy current testing sensor. The diameter of a magnetic core used in each of the pair of eddy current testing coils is within the range of 0.1 mm to 0.5 mm.