Abstract: A test system for detecting corrosion under a coating on a structure, the coating being transmissive to microwaves and the surface being reflective to microwaves. A microwave generator generates microwaves of a desired power and frequency, which are delivered to a test head that both transmits the microwaves to the surface and receives the microwaves as reflected from the structure. A corrosion detection processor measures the phase and amplitude of the reflected signal, and compares measurement data to reference data to determine if corrosion under the coating is indicated.

Abstract: A method for in-situ detection of coating defects on a buried pipeline. The pipeline is under cathodic protection or otherwise carries a current applied to its pipe walls. A magnetic field sensor array is placed within the pipeline and moved along its length. As the sensor array travels, it detects the magnetic fields within the pipeline. The sensor output is compared with “expected” data, which represents interior magnetic fields of the pipeline without coating defects. Because electrical current leaks through a coating defect, the current is altered on the pipe wall at the defect. This in turn alters the interior magnetic fields, and a change in the interior magnetic fields indicates a coating defect.

Abstract: A method for in-situ detection of coating defects on a buried pipeline. The pipeline is under cathodic protection or otherwise carries a current applied to its pipe walls. A magnetic field sensor array is placed within the pipeline and moved along its length. As the sensor array travels, it detects the magnetic fields within the pipeline. The sensor output is compared with “expected” data, which represents interior magnetic fields of the pipeline without coating defects. Because electrical current leaks through a coating defect, the current is altered on the pipe wall at the defect. This in turn alters the interior magnetic fields, and a change in the interior magnetic fields indicates a coating defect.

Abstract: A system and associated methods for acquiring and analyzing LEIS data from a buried structure, such as a pipeline. A special probe having adjustable electrodes is placed in the soil above the structure. A voltage is applied to the structure, causing more current to emanate from a coating defect than from intact coating. The probe electrodes acquire a response signal, which is analyzed to detect the defect.

Abstract: A system and associated methods for acquiring and analyzing LEIS data from a buried structure, such as a pipeline. A special probe having adjustable electrodes is placed in the soil above the structure. A voltage is applied to the structure, causing more current to emanate from a coating defect than from intact coating. The probe electrodes acquire a response signal, which is analyzed to detect the defect.

Abstract: The system and method provides a means for inspecting pipelines that have obstructions which prevent conventional inspection pigs from passing the obstructions. The invention uses remote-field eddy current inspection techniques and a uniquely configured excitation coil for inline inspection of pipelines having valves and other fittings that severely restrict or prevent the use of conventional inspection pigs. A unique collapsible excitation coil and a collapsible sensor array enables an inspection pig using these features to pass pipeline obstructions that prevent passage by conventional inspection pigs. The collapsible coil and sensor array provide means for reducing the diameter of an inspection pig to enable it to pass obstructions in the pipeline.

Abstract: The invention provides an electronic circuit means for injecting virtual flaw signals into the signal path between a NDT test instrument and an associated probe. This enables a system that is capable of generating virtual flaw signals to present virtual flaws to an NDT inspector while enabling the test probe to present actual flaws to the NDT inspector. An eddy current test (ECT) embodiment of the invention comprises a means for deriving a reference signal from an ECT instrument excitation signal, a means for modulating the gain and phase of the reference signal by commands from a control computer, and a means for summing the modulated signal with the ECT probe output signal for transmission to the ECT instrument.

Abstract: The system and method provides a means for inspecting pipelines that have obstructions which prevent conventional inspection pigs from passing the obstructions. The invention is a system and method that uses remote-field eddy current inspection techniques and a uniquely configured excitation coil for inline inspection of pipelines having valves and other fittings that severely restrict or prevent the use of conventional inspection pigs. The invention relies on a unique collapsible excitation coil and a collapsible sensor array that enables an inspection pig incorporating the invention to pass pipeline obstructions that prevent passage by conventional inspection pigs. The invention provides a means for reducing the diameter of the inspection pig to enable it to pass obstructions in the pipeline.

Abstract: The system and method provides an NDT inspector with a realistic simulation of inspecting a test piece while injecting virtual flaws for display on an NDT instrument, while also presenting actual flaws to the inspector. A conventional NDT test probe and instrument are connected to the system at the probe leads interface. The system provides means for monitoring probe position and probe liftoff, means for storing virtual flaw signals and associated locations on a test piece, and means for providing a virtual flaw signal to the NDT instrumentation to simulate the response of the actual probe. The invention provides for nondestructive test method qualification and probability of detection determination, for establishing and maintaining nondestructive testing proficiency of inspectors, for periodically presenting flaw signals to inspectors during routine inspections, and for ensuring sufficient scan coverage for detection of material defects in a test piece.

Abstract: The system and method provides an NDT inspector with a realistic simulation of inspecting a test piece while injecting virtual flaws for display on an NDT instrument, while also presenting actual flaws to the inspector. A conventional NDT test probe and instrument are connected to the system at the probe leads interface. The system provides means for monitoring probe position and probe liftoff, means for storing virtual flaw signals and associated locations on a test piece, and means for providing a virtual flaw signal to the NDT instrumentation to simulate the response of the actual probe. The invention provides for nondestructive test method qualification and probability of detection determination, for establishing and maintaining nondestructive testing proficiency of inspectors, for periodically presenting flaw signals to inspectors during routine inspections, and for ensuring sufficient scan coverage for detection of material defects in a test piece.

Abstract: The invention provides an electronic circuit means for injecting virtual flaw signals into the signal path between a NDT test instrument and an associated probe. This enables a system that is capable of generating virtual flaw signals to present virtual flaws to an NDT inspector while enabling the test probe to present actual flaws to the NDT inspector. An eddy current test (ECT) embodiment of the invention comprises a means for deriving a reference signal from an ECT instrument excitation signal, a means for modulating the gain and phase of the reference signal by commands from a control computer, and a means for summing the modulated signal with the ECT probe output signal for transmission to the ECT instrument.

Abstract: A method utilizing high-speed digital computers and high resolution display systems for stacking a plurality of two-dimensional complex displays acquired from individual NDE scans over the surface of a material being inspected. The solid three-dimensional image constructed incorporates the two dimensions typically provided by eddy current-type testing components, i.e., the imaginary or vertical component and the real or horizontal component, and a third dimension that represents the physical orthogonal distance between sequential scans. The solid three-dimensional image is generated by connecting corresponding positional points on adjacent two-dimensional plane displays. The closed solid figure generated results when a null or equilibrium point away from the specific signal features is encountered. Appropriate coloration or shading on the three-dimensional image highlights the features for visual inspection.

Abstract: A method for rapidly detecting and locating reinforcing steel corrosion in concrete structures using non-linear harmonic and intermodulated frequencies of electromagnetic signals. The method comprises transmitting either a single primary frequency or two primary frequencies into the concrete structure in the general direction of the reinforcing steel. The reflected/generated signal, which is composed of the primary frequencies and of various harmonics and intermodulation components, is received, filtered, and amplified. A third order harmonic frequency is isolated with a band pass filter, is amplified, and is compared with the amplitudes of the primary frequencies. Intermodulation frequencies, primarily the combination of the primary of a frequency and the second harmonic of a second frequency, or the primary of a second frequency and the second harmonic of a first frequency, are isolated by appropriate band pass filter, are amplified, and are compared with the primary frequency or frequencies.