Patent · US Expired

Method for processing echo sounding data collected from boreholes in the earth

US5200894A · kind A · utility

16Cited by
9References
61Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 16, 1990
Grant dateApr 6, 1993
Priority date
Expiry dateJul 16, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V1/137
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An echo sounding system includes an acoustic gun which is mounted to the wellhead of a borehole. The acoustic gun produces an acoustic pulse which is transmitted down the borehole. A tubing string is installed in the borehole and it has substantially evenly spaced collars. Fluid is pumped from the borehole, or well, by use of a reciprocating pump driven by a pump rod extending to the surface. The acoustic pulse produces reflections when it strikes the tubing collars and the surface of the fluid. A microphone detects the reflections to produce a return signal. This signal is digitized and stored. The digitized signal is processed to detect the rate of the collar reflections and the stored signal is narrowband filtered with a passband filter centered at the rate of receipt of the collars. Each cycle of the narrowband filtered signal corresponds to one collar reflection. In this signal, each cycle is counted, and extrapolation used when necessary to produce a collar count extending from the surface to the liquid surface. This is multiplied by the average joint length to produce the depth to the liquid surface. The system further detects the liquid level and displays it as a marker on …

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