The Babcock & Wilcox Company

Mcdermott Technology, Inc.

Donald M Stevens

Michael O Robertson

John E Coulter

Daniel T MacLauchlan

George H Harth, Iii

Jimmy W Hancock

Hubert L Whaley

Thomas Powers

Paul John Berbakov

A method for detecting the location of an edge, interface, seam or other structure of a workpiece uses one or two electromagnetic acoustic transducers (EMATs) to transmit an ultrasonic wave along the workpiece toward the edge and to receive a reflected wave. The velocity of the wave in the material is used in conjunction with the round trip time-of-flight (TOF) of the transmitted and reflected wave, to calculate the location of the edge. This is done by placing the transducer or transducers at known locations on the workpiece. A surface wave or 90 degree shear wave can be utilized and no contact is needed between the transducer and the surface of the workpiece. Rough and/or dirty surfaces and hostile environments can be accommodated while practicing the invention.

Edge detection and seam tracking with EMATs

An ultrasonic inspection method for measuring the thickness of non-welded (non-metallurgically bonded) cladding on the inside surface of a vessel from an outside diameter surface of the vessel relies upon the occurrence of a phase change at an interface between the base metal and cladding layers to precisely determine its presence and location. By measuring the length of time for the ultrasonic pulse to propagate through the cladding material, suitable predetermined calibration standards for the cladding material in question can be used to convert the time of flight of the ultrasonic pulses through the cladding into a thickness of the cladding. The cladding thickness can be measured from an outside surface of the vessel whether or not it is empty and/or without stopping the process and/or draining it, and the method can even be employed at elevated temperatures through the use of known delay lines. Alternatively, if safe access to the interior portion of the vessel is available, an internal direct inspection can be performed to determine the thickness of the non-welded cladding using a modification of the technique in which a first multiple or second reflection signal from the base metal/cladding layer interface is used.

Ultrasonic technique for measuring the thickness of cladding on the

An apparatus and method are disclosed for determining the integrity of coated nuclear fuel particles by evaluating acoustic parameter measurements of the particles during controlled loading.

Monitoring of fuel particle coating cracking

A method and apparatus for detecting the presence of surface corrosion under insulation on a piping structure employs artificially generated, broadband acoustic sound waves to interrogate the piping structure. The sound waves are coupled into the piping structure and detected after they have propagated through and interacted with a portion of the piping structure. The amplitude of RMS voltage signals indicative of the detected sound waves is used to determine whether or not surface corrosion is present. Highly corroded pipes have been shown to yield relatively low RMS voltage signals whereas the lack of corrosion yields relatively high RMS voltage signals.

Acoustic emission for detection of corrosion under insulation

An apparatus and method are disclosed for determining the integrity of coated fuel particles via acoustic characterization. Particle supply means (4) drops the nuclear fuel particles (2) individually onto the face (6) of a transducer (8). The generated signal which is indicative of the integrity of the coating on the dropped particle is analyzed with analyzing means (26, 28, 30) for discriminating between a flawed and an unflawed particle.

Growing community of inventors

Lovingston, VA, United States of America

Donald M Stevens