Southwest Research Institute

US Government As Represented by the Secretary of the Army

Ronald Herbert Peterson

Hegeon Kwun

Gary Lane Burkhardt

Keith S Pickens

Albert Joseph Parvin, Jr

Jay L Fisher

Alfred Eugene Crouch

Todd Hegert Goyen

Albert J Parvin

Robert L Spinks, Jr

Joseph W Brophy

Richard Franklin Tennis

A method and system for detecting corrosion metal loss. One may provide a guided wave probe that includes an electromechanical device and a corrosion probe. This may be followed by measuring a baseline guided wave attenuation value of the corrosion probe with no corrosion. One may then periodically measure the guided wave attenuation of the corrosion probe and detect an increase in guided wave attenuation values and identify metal corrosion associated with the increase in guided wave attenuation values. This may then be followed by estimating the corrosion metal loss of the metallic component.

Method and device for measuring corrosion metal loss

An economical, flexible, magnetostrictive sensor for use on planar and/or curved structural surfaces, for guided-wave volumetric inspection of the structure. The flexible plate MsS probe includes a flexible strip of magnetostrictive material that is adhered to the base of a flat, flexible, conductor coil assembly. The conductor coil assembly has a core that is composed of a thin flexible strip of metal, a layer of an elastomeric material, and a thin permanent magnet circuit. The flexible core is surrounded by a flat flexible cable (FFC) that is folded and looped over the layers of the core. The exposed conductors at the ends of the FFC are shifted from each other by one conductor and joined so that the parallel conductors in the FFC form a flat, flexible, continuous coil. The entire probe assembly may be bent to match the curved contours of the surface of the structure under investigation.

Flexible plate magnetostrictive sensor probe for guided-wave inspection of structures

The present disclosure relates to a device and method for pipeline inspection, The inspection device may include an exciter coil capable of providing an alternating current magnetic field and producing eddy currents. A plurality of sensors may then be provided which are capable of sensing a magnetic field produced by the eddy currents and the sensors may be engaged with a sensor shoe. The sensors may then be capable of being positioned at a first distance Dwith respect to an inner pipe wall surface and capable of providing coupling to the magnetic field produced by the eddy currents. The sensor shoe may also be capable of retracting to a second distance D, wherein D&#x3c;D. The sensor shoe may be connected to a sensor support arm wherein the support arm may be pivotably attached to a fixed hub and to a control arm which control arm may then be pivotably attached to a driven hub.

Pipeline inspection using variable-diameter remote-field eddy current technology

Systems and methods are described that carry out an intelligent, variable, time-gain control (TGC) of signal amplification in a long-range, guided-wave inspection and monitoring system. The systems and methods compensate for signal attenuation over the longer distances that guided-wave inspection techniques are capable of operating with. The sensor signal received is divided into relevant frequency bands that are each subjected to a variable TGC through separate variable gain amplifiers (VGAs). The gain selection is processor controlled through the use of a digital look-up table (LUT) stored with predetermined gain functions and/or data that are both time and frequency specific. The signal components are re-combined and digitized for further signal analysis and defect detection. The LUT is established through one or more methods including a weld signal amplitude equalization approach and a background noise equalization approach.

Time-gain control method and system for long-range guided-wave inspection and monitoring

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.

Method and system for injecting virtual flaw signals into a nondestructive test system

An apparatus and method for directing ultrasonic and magnetostrictively generated mechanical waves from an exterior point to an interior point within a small diameter tube, pipe, or cylindrical structure. The present invention incorporates an external mechanism for generating waves in a cylindrical waveguide tube gun of a size small enough for insertion into the target tube and configured so as to maintain mechanical contact with an inside diameter of the target tube. Standard ultrasonic wave generating devices or magnetostrictive/mechanical wave generating coils are positioned on the waveguide external to the target tube and generate appropriate mechanical waves through the waveguide to a point interior to the target tube. A mechanical interface between the waveguide and the inside diameter surface of the tube is positioned and provided at a point within the target tube to transfer both the interrogating waves and the received return signal waves between the target tube and the waveguide. Appropriate sensor devices for ultrasonic and/or magnetostrictive/mechanical waves are positioned to receive the returned signals and interpret the impedance mismatches that indicate flaws, supports and geometric variations in the tubular wall. Appropriate signal reception, amplification, and filtration elements are positioned to convert the received signal into a signal voltage suitable for display and processing.

Apparatus and method for inspection of pipes and tubes using guided wave

A pyrotechnic device (UUT) is automatically tested for thermal response cacteristics using an automatically balanced Wheatstone bridge. One branch of the bridge is a series of relay connected resistances which are selectively connected to coursely balance the bridge using a voltage developed across the UUT. An FET in series with the series of resistances, in response to the bridge null currents, finely balances the bridge. A low constant current pulse is used to generate a voltage across the UUT and to balance the bridge. A second high constant current pulse is used to measure the transient thermal response of the UUT. The transient test current pulses are generated automatically or manually and whose amplitude and repetition rate are manually set. The pulses are generated by a D/A converter whose output is fed to a constant current generator coupled to a manually settable resistance range for setting the value of the high current transient test pulse amplitude. The lower value initial balance current pulse is separately settable by internal calibration switches and straps. The entire test is less than 40 ms.

Growing community of inventors

Helotes, TX, United States of America

Ronald Herbert Peterson