Assessing a solids deposit in an oilfield pipe
US7095676B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Jul 30, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2634
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Tube waves are used to locate and characterize a solids deposit inside a fluid-filled pipe. An acoustic tube wave pulse is transmitted along the pipe. On encountering a solids deposit, the tube wave pulse is perturbed and partially reflected by changes in the boundary conditions between the fluid and the pipe to produce two deposit-modified acoustic waves. One is a perturbed wave travelling in the same direction as the tube wave pulse. The other is a reflected wave travelling in the opposite direction. One of these deposit-modified acoustic waves is received to produce an acoustic signal. Accumulated acoustic signals are processed by Fast-Fourier Transform to produce frequency-based digital data. Phase data from the frequency-based digital data is inverted to produce slowness spectrum data. Power data from the frequency-based digital data is inverted to produce attenuation spectrum data. Spectrum data is used to locate a solids deposit in the pipe. Inversion model processing of the spectrum data is used to estimate solids deposit thickness and type.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.