Noninvasive detection of corrosion, mic, and foreign objects in containers, using guided ultrasonic waves
US6363788B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2000 |
| Grant date | Apr 2, 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 (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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.