Patent · US Expired

Method and apparatus for enhanced acoustic mud pulse telemetry during underbalanced drilling

US7138929B2 · kind B2 · utility

16Cited by
9References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 8, 2001
Grant dateNov 21, 2006
Priority date
Expiry dateJul 8, 2022

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B21/085
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A method and system for telemetry through a compressible drilling fluid during underbalanced drilling is disclosed. A reflector (110) is positioned downstream from the gas inlet (84) and causes reflected pressure waves having the same pressure polarity as incident pressure waves. A pressure sensor (92) is positioned below the reflector to sense pressure in the compressible drilling fluid. The reflector (110) can be a fixed orifice plate or an adjustable aperture. A borehole communication system is also disclosed wherein a pair of pressure sensors are positioned on either side of a flow restriction (118) located in the gas conduit leading to the gas injector. The flow restriction can be a valve used to regulate the flow rate of the gas being supplied into the drilling fluid, or it can be separate venturi or orifice plate.

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