Patent · US Expired

Method and apparatus for placing and interrogating downhole sensors

US6408943B1 · kind B1 · utility

187Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 17, 2000
Grant dateJun 25, 2002
Priority date
Expiry dateJul 17, 2020

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B47/138
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A method and system is shown to passively monitor cement integrity within a wellbore. Different types of sensors (pressure, temperature, resistivity, rock property, formation property etc.) are “pumped” into place by placing them into a suspension in the cement slurry at the time a well casing is being cemented. The sensors are either battery operated, or of a type where external excitation, (EMF, acoustic, RF etc.) may be applied to power and operate the sensor, which will send a signal conveying the desired information. The sensor is then energized and interrogated using a separate piece of wellbore deployed equipment whenever it is desired to monitor cement conditions. This wellbore deployed equipment could be, for example, a wireline tool.

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