Data transmission device

• US 20060044155A1
• Filed: 11/28/2003
• Published: 03/02/2006
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Geoservices Equipements (Schlumberger NV)
• Original Assignee: Geoservices Equipements (Schlumberger NV)
• Inventors: Millet, Francois, Le Briere, Bruno, Chatelet, Vincent
• Granted Patent: US 7,652,592 B2
• Time in Patent Office: Days
• US Class Current: 340/854.300
• CPC Class Codes: E21B 47/13 by electromagnetic energy, e.g. radio frequency

Abstract

The device relates to an installation comprising a cavity (13) extending from the surface of the ground (17) and provided with at least one electrically conductive tubular element (21; 25). The device comprises a single-strand smooth cable (3) for supporting an action and/or measurement assembly (5), which cable is electrically conductive and has a breaking strength greater than 300 daN, and is disposed in the tubular element (21; 25). The surface of the cable (3) is electrically insulated at least in part from said tubular element (21; 25). The device includes transmitter means (9, 11) and receiver means (9, 11) for transmitting and receiving an electrical and/or electromagnetic signal, said means being situated in the vicinity of the surface (17) and in the cavity (13), and being electrically connected firstly to the cable (3) and secondly to the tubular element (21; 25) and/or to the formation (19). The invention is applicable to transmitting information and to controlling tools in an oil well.

Claims

1. A device for transmitting data in an installation for working fluids contained under ground, the installation comprising a cavity defined in an underground formation and extending from the surface of the ground, said cavity being provided with at least one electrically conductive tubular element, the device being of the type comprising a single-strand smooth cable for supporting an action and/or measurement assembly, the cable having a breaking strength greater than 300 daN, being made of an electrically conducive material and being disposed in the tubular element between a first point at the surface of the ground and a second point within the cavity, wherein the surface of the cable is electrically insulated, at least in part, from said tubular element, and wherein the device further comprises transmitter means for transmitting an electrical and/or electromagnetic signal, situated in the vicinity of one or both of the first and second points, and receiver means for receiving an electrical and/or electromagnetic signal situated in the vicinity of the other one or both of the first and second points;

each of said transmitter means and said receiver means being electrically connected firstly to the cable and secondly to the tubular element and/or to the formations;

the cable constituting a portion of a loop for conveying the electrical and/or electromagnetic signal between the transmitter means and the receiver means.

2. A transmission device according to claim 1, wherein the surface of the cable carries a continuous coating of insulating material and is electrically insulated from said tubular element.

3. A transmission device according to claim 2, wherein the thickness of the continuous coating of insulating material is equal to half the difference in diameter between two standard and non-coated cables.

4. A transmission device according to claim 1, wherein the surface of the cable is provided at regular intervals with centralizers of insulating material for electrically insulating said tubular element.

5. A transmission device according to claim 1, wherein the transmitter and receiver means in the vicinity of the first and second points are electrically connected to said tubular element and wherein the signal transmitted by the transmitter means and received by the receiver means is an electrical signal.

6. A transmission device according to claim 1 wherein the cavity is provided with at least a first tubular element and a second tubular element disposed inside the first element, and wherein the cable is disposed in the annular space between the first and second elements.

7. A transmission device according to claim 1, wherein the surface of the cable has at least one electrical contact point with said tubular element, and wherein the transmitter means and/or receiver means in the vicinity of the first and second points and said tubular element are electrically connected to the formation.

8. A transmission device according to claim 7, wherein the electrical signal transmitted by the transmitter means in the vicinity of the first point is injected to a first dipole comprising firstly an electrical contact point between the cable and the transmitter means in the vicinity of the first point, and secondly an electrical contact point between the formation and the transmitter means in the vicinity of the first point;

the first dipole generating an electromagnetic signal that is received by a second dipole comprising firstly one of said electrical contact points between the cable and the tubular element, and secondly an electrical contact point between the tubular element, and the receiver means in the vicinity of the second point, with the electromagnetic signal received by the second dipole generating an electrical signal which is conveyed to the receiver means in the vicinity of the second point.

9. A transmission device according to claim 7 wherein the electrical signal transmitted by the transmitter means in the vicinity of the second point is injected into a second dipole comprising firstly one of said electrical contact points between the cable and the tubular element, and secondly an electrical contact point between the tubular element and the transmitter means in the vicinity of the second point, said second dipole generating an electromagnetic signal received by a first dipole comprising, firstly an electrical contact point between the cable and the receiver means in the vicinity of the first point, and secondly an electrical contact point between the formation and the receiver means in the vicinity of the first point;

the electromagnetic signal received by the first dipole generating an electrical signal that is conveyed to the receiver means in the vicinity of the first point.

10. A transmission device according to claim 1, wherein the electrical contact between the formation and the transmitter and/or receiver means in the vicinity of the first point takes place via a conductor member anchored in the ground.

11. A transmission device according to claim 1, wherein the transmitter means and the receiver means for transmitting and receiving an electrical and/or an electromagnetic signal are situated in the vicinity of respective ones of the first and second points.

12. A transmission device according to claim 1, wherein the transmitter means for transmitting an electrical and/or an electromagnetic signal are situated solely in the vicinity of one of the first and second points, and the receiver means for receiving an electrical and/or an electromagnetic signal are situated solely in the vicinity of the other one of the first and second points.

13. An installation for working fluids contained underground, the installation comprising a cavity defined in an underground formations extending from the surface of the ground and closed on the surface by a wellhead, said cavity being provided with at least one electrically conductive tubular element, the installation including a transmission device according to claim 1.

14. An installation according to claim 13, including an applicator device for applying an insulating coating on the cable.

15. An installation according to claim 14, in which the wellhead is preceded by an airlock provided with a sealing device for the cable, wherein the applicator device for applying the insulating coating on the cable is disposed inside the airlock downstream from the sealing device.

16. An installation according to claim 14, including deployment means and an alignment device for putting the cable into alignment in the wellhead, the alignment device comprising at least one pulley, wherein the applicator device for applying the insulating coating on the cable is disposed between the deployment means and the alignment device, and wherein the or each pulley is electrically insulated from the wellhead and/or the formation.