Patent · US Expired

Method for processing signals in a cement bong logging tool

US7411864B2 · kind B2 · utility

6Cited by
11References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 2005
Grant dateAug 12, 2008
Priority date
Expiry dateMay 17, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V1/46
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A longitudinally segmented acoustic transducer for a cement bond logging (CBL) tool having a plurality of adjoining PZT ring-like segments driven synchronously in parallel by one or more pulses and caused to vibrate in an anti-resonant mode, substantially below the resonant frequency of an individual segment when used in a transmitting application. When used in a receiving application, each of the plurality of transducer rings are caused to vibrate by acoustic signals detected by the transducer array, also in an anti-resonant mode. High speed digital signal processing enables on-depth, high quality data for all azimuths at each depth to be obtained, processed, normalized and either sent to the surface in real time for each 20 Hz firing cycle, as the CBL tool is pulled toward the surface, or stored in a memory module in digital form for later retrieval. Built-in calibration factors used for normalizing the output signals to the operating conditions of use may be accessed at any time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.