Digital Wave Corporation

The United States of America As Represented by the Administrator of the

United States of America As Represented by the Administrator of Nasa

Michael R Gorman

Steven M Ziola

William H Prosser

William J Miller

Wei Huang

Daniel F Perey

Brian M Burks

Edgar F Scales

Provided herein are systems and methods for achieving an extended service life for a pressure vessel that has experienced a prior service life. In some embodiments, the service life of the vessel has expired. The service vessel has an unknown damage condition, including defects sustained during the service life. Despite these defects and unknown accumulated damage state, the embodiments described herein may be used to test these vessels, to safely pressurize the vessels beyond pressures deemed safe for the vessel to experience in its damaged state, and to recommission a new service life for the vessel. The recommissioning of the vessel for an additional service interval may include meeting certain requirements for the pressure vessel, and embodiments described herein include exemplary measurements and observations to assure these requirements of the rejuvenated vessel are met.

Treatment method for service life extension of pressure vessels

Methods and apparatus for ultrasonically scanning cylinders are provided. The methods and apparatus employ as few as one ultrasonic sensor for full immersion scanning and defect detection. Self-centering fixturing spins the cylinder, reducing vibration, allowing for fast ultrasonic scans. To create the 45 degree angle beam shear waves for the circumferential scans, the ultrasonic sensor is offset from the centerline of the cylinder, creating the correct angle for excitation of the shear wave.

Device and method designed for ultrasonically inspecting cylinders for longitudinal and circumferential defects and to measure wall thickness

An acoustic monitoring device has at least two acoustic sensors with a triggering mechanism and a multiplexing circuit. After the occurrence of a triggering event at a sensor, the multiplexing circuit allows a recording component to record acoustic emissions at adjacent sensors. The acoustic monitoring device is attached to a solid medium to detect the occurrence of damage.

System for multiplexing acoustic emission (AE) instrumentation

Ultrasonic energy in the form of guided waves (plate waves or Lamb waves) is launched into the wall of a container. The guided wave propagates around the circumference of the container from a transmitting transducer to a receiving transducer. Analysis of the received waves determines the presence of corrosion pitting and MIC nodules on the container inner wall, as well as the existence of foreign objects in intimate contact with the container wall. The guided waves are created with wideband transducers excited at certain frequencies that depend on the material and geometry of the part being measured. The guided wave ultrasonic energy is maximized with a shaped tone burst pulse at the specified frequency rather than an electrical spike commonly used to excite transducers in standard ultrasonic search units. The energy and energy ratio of both the direct and wrap fields are measured and related to the container inner wall condition and the presence of any corrosion in the container or obstructions in intimate contact with the container wall.

Noninvasive detection of corrosion, MIC, and foreign objects in containers using guided ultrasonic waves

Ultrasonic energy in the form of guided waves is launched into the wall of a fluid-filled container. The guided wave propagates around the circumference of the container from a transmitting transducer to a receiving transducer. Part of the guide wave energy leaks into the fluid in the form of bulk waves, reflects off the inner wall on the other side and enters back to the receiving transducer trailing the direct wave. Analysis of the received waves determines the presence of corrosion pitting and MIC nodules on the container inner wall, and fluid level. In addition, it determines whether foreign objects are inside the container. The guided waves are created with wideband transducers excited at certain frequencies that depend on the material and geometry of the part being measured. The leakage energy is maximized with a shaped tone burst pulse at the specified frequency. The energy and energy ratio of both the direct and leakage fields are measured and related to the container inner wall condition and the presence of any foreign objects in the fluid.

Noninvasive detection of corrosion, MIC, and foreign objects in fluid-filled pipes using leaky guided ultrasonic waves

A hand-held Variable Angle Membrane (VAM) ultrasonic scanning head consisting of transmitting and receiving transducers is used to excite guided waves to detect corrosion, MIC and foreign objects in containers such as pipes. The scanning head includes transducers mounted on a fluid filled housing sealed by a membrane. This system couples ultrasound from the transducer to the pipe wall. The transducer housings are mounted in a rigid frame that holds the ultrasonic transducer housings a specific distance apart and allows each transducer housing to rotate about a pivot point. The membrane deforms to the pipe diameter to be scanned. The scanning head is adjusted to perform inspections in various container diameters and thicknesses. Once adjusted for diameter and thickness, the operator places the scanning head on the pipe and couples the rubber membranes to the pipe with a small amount of couplant. Separate electronics excite the transmitting transducer, and then condition the signal from the receiving transducer for analysis.

Hand-held variable angle membrane (VAM) ultrasonic scanning head for the noninvasive detection of corrosion, MIC and foreign objects in pipes

Noninvasive detection of corrosion, MIC, and foreign objects in fluid-filled containers using leaky guided ultrasonic waves

Noninvasive detection of corrosion, mic, and foreign objects in containers, using guided ultrasonic waves

A method for determining the angle of impact of an object on a thin-walled structure which determines the angle of impact through analysis of the acoustic waves which result when an object impacts a structure. Transducers are placed on and in the surface of the structure which sense the wave caused in the structure by impact. The waves are recorded and saved for analysis. For source motion normal to the surface, the antisymmetric mode has a large amplitude while that of the symmetric mode is very small. As the source angle 22 increases with respect to the surface normal, the symmetric mode amplitude increases while the antisymmetric mode amplitude decreases. Thus, the angle of impact is determined by measuring the relative amplitudes of these two lowest order modes.

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Englewood, CO, United States of America

Michael R Gorman