Noninvasive detection of corrosion, MIC, and foreign objects in fluid-filled containers using leaky guided ultrasonic waves
US6367328B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2000 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Jul 11, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2695
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.