Antenna for Use in a Downhole Tubular

• US 20140306853A1
• Filed: 06/18/2014
• Published: 10/16/2014
• Est. Priority Date: 05/09/2007
• Status: Active Grant

• Current Assignee: Weatherford Technology Holdings, LLC (Weatherford International PLC)
• Original Assignee: Petrowell Limited (Weatherford International PLC)
• Inventors: Purkis, Daniel, MacLeod, Lain Morrison
• Granted Patent: US 10,262,168 B2
• Time in Patent Office: Days
• US Class Current: 343/719
• CPC Class Codes: E21B 47/09 Locating or determining the position of objects in boreholes or wells , e.g. the position of an extending arm; Identifying the free or blocked portions of pipes
• CPC Class Codes: E21B 47/092 by detecting magnetic anomalies
• CPC Class Codes: E21B 47/11 using tracers; using radioactivity
• CPC Class Codes: E21B 47/13 by electromagnetic energy, e.g. radio frequency
• CPC Class Codes: E21B 47/138 Devices entrained in the flow of well-bore fluid for transmitting data, control or actuation signals
• CPC Class Codes: E21B 47/26 Storing data down-hole, e.g. in a memory or on a record carrier
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: H01Q 1/04 Adaptation for subterranean or subaqueous use
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment

Abstract

An antenna for use in a downhole tubular. The antenna comprises a generally cylindrical housing and a coiled conductor located within a portion of the housing and separated therefrom by insulating material. The portion of housing has a greater internal diameter than an external diameter of the coiled conductor.

Claims

1. An antenna for use in a downhole tubular, the downhole tubular having a conduit for the passage of fluids through the downhole tubular, the antenna comprising a generally cylindrical housing having a throughbore for the passage of fluid through the housing, the throughbore of the housing being in fluid communication with the conduit in the downhole tubular, and a coiled conductor located within a portion of the housing of the antenna and being insulated from the housing, the portion of the housing in which the coiled conductor is located having a greater internal diameter than an external diameter of the coiled conductor, the antenna comprising a non-conducting liner, wherein the coiled conductor is coiled around the liner and is co-axial therewith, the antenna being adapted to read data from and/or transfer data to at least one RFID tag carried in fluid flowing in the throughbore of the housing, and wherein the liner is arranged on an inner surface of the throughbore in the housing of the antenna.

2. An antenna according to claim 1, wherein the conductor is helically coiled around the liner.

3. An antenna according to claim 1, wherein the housing and the liner form a seal around the coiled conductor.

4. An antenna according to claim 1, wherein the liner is non-magnetic.

5. An antenna according to claim 1, wherein the antenna is operable in the frequency range from 50 to 200 kHz.

6. An antenna according to claim 1, wherein the antenna is operable in the frequency range between 125 and 134 kHz.

7. An antenna according to claim 1, wherein the antenna is of sufficient length to charge and read the at least one RFID tag when the at least one RFID tag passes therethrough.

8. An antenna according to claim 1, wherein the antenna has a length of less than 10 meters.

9. An antenna according to claim 1, wherein the antenna includes a battery and an electronics pack.

10. An antenna according to claim 1, wherein the throughbore through the housing of the antenna is co-axial with the bore of the conduit through the tubular.

11. An antenna according to claim 1, wherein the liner and the conduit each have an inner diameter and the inner diameter of the liner is not less than the inner diameter of the conduit.

12. An antenna according to claim 11, wherein the inner diameter of the liner is the same as the inner diameter of the conduit.

13. An antenna according to claim 1, wherein the liner has an inner surface and an outer surface, and wherein the coiled conductor is coiled around the outer surface of the liner, and the inner surface of the liner is exposed to the interior of the throughbore of the housing.

14. An antenna according to claim 1, wherein the liner is formed from a non-metallic material.

15. An antenna according to claim 1, wherein the conductor coil is separated from the housing.

16. An antenna according to claim 15, wherein the conductor coil is separated from the housing by an insulator.

17. An antenna according to claim 1, wherein the conductor coil is recessed in a helical groove on the outer surface of the liner.

18. An antenna assembly comprising a downhole tubular comprising a conduit and having a first antenna according to claim 1, the first antenna being configured to read data from a first RFID tag passing through the conduit of the tubular, and the downhole tubular having a second antenna according to claim 1, the second antenna being configured to read data from a second RFID tag passing through the conduit of the tubular, wherein the first RFID tag is programmed to be read by the first antennae, but not the second antenna, and wherein the second RFID tag is programmed to be read by the second antenna but not the first antenna.

19. An antenna for use in a downhole tubular, the downhole tubular comprising a conduit having an axial bore with an inner surface for the passage of fluids through the downhole tubular, the antenna comprising a generally cylindrical housing having a throughbore with an inner surface for the passage of fluid through the housing and a recess extending from the inner surface of the housing, the throughbore of the housing being in fluid communication with the conduit in the downhole tubular, the antenna having a coiled conductor located within the recess and being insulated from the housing, the recess having an inner surface with a greater internal diameter than an external diameter of the coiled conductor, the antenna including a cylindrical, non-conducting, non-magnetic liner with a central bore in fluid communication with the conduit through the tubular, the liner having an inner and an outer surface, the liner being disposed in the recess of the housing, the diameter of the inner surface of the liner being matched with the diameter of the inner surface of the housing, wherein the coiled conductor is helically and co-axially coiled around the outer surface of the liner and is disposed radially between the outer surface of the liner and the inner surface of the recess, the antenna being adapted to read data from and/or transfer data to at least one RFID tag carried in fluid flowing in the bore of the liner.

20. An antenna according to claim 19, wherein the conductor is sealed off from the conduit through the tubular by seals disposed between the liner and the housing.