Secure activation of a downhole device

• US 20050045331A1
• Filed: 08/27/2004
• Published: 03/03/2005
• Est. Priority Date: 10/27/1998
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Lerche, Nolan C., Brooks, James E., Wong, Choon Fei
• Granted Patent: US 7,347,278 B2
• Time in Patent Office: Days
• US Class Current: 166/297
• CPC Class Codes: E21B 41/0021 Safety devices, e.g. for preventing small objects from falling into the borehole
• CPC Class Codes: E21B 43/1185 Ignition systems
• CPC Class Codes: E21B 43/11857 firing indication systems
• CPC Class Codes: E21B 43/119 Details, e.g. for locating perforating place or direction
• CPC Class Codes: E21B 47/12 Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
• CPC Class Codes: F42D 1/05 Electric circuits for blasting

Abstract

A system includes a well tool for deployment in a well, a controller, and a link coupled between the controller and the well tool. The well tool comprises plural control units, each of the plural control units having a microprocessor and an initiator coupled to the microprocessor. Each microprocessor is adapted to communicate bi-directionally with the controller. The controller is adapted to send a plurality of activation commands to respective microprocessors to activate the respective control units. Each activation command containing a unique identifier corresponding to a respective control unit.

Claims

1. A system comprising:

a well tool for deployment in a well;

a controller;

a link coupled between the controller and the well tool, wherein the well tool comprises plural control units, each of the plural control units having a microprocessor and an initiator coupled to the microprocessor,

each microprocessor adapted to communicate bi-directionally with the controller,

wherein the controller is adapted to send a plurality of activation commands to respective microprocessors to activate the respective control units,

each activation command containing a unique identifier corresponding to a respective control unit.

2. The system of claim 1, wherein each control unit includes a support structure, the microprocessor and initiator being mounted on the support structure.

3. The system of claim 2, wherein the support structure comprises a flexible circuit.

4. The system of claim 2, wherein the support structure comprises a flex cable.

5. The system of claim 1, wherein the initiator includes at least one of an exploding foil initiator, an exploding bridge wire, a hot wire, and a semiconductor bridge.

6. The system of claim 1, wherein the well tool further comprises tool subs, each tool sub comprising a corresponding control unit and an explosive, the explosive to be detonated by the initiator.

7. The system of claim 6, wherein the well tool further comprises a safety sub coupled to the tool subs, the safety sub having identical components as at least one of the tool subs except that the safety sub does not include an explosive,

the safety sub to prevent arming of the tool subs until after activation of the safety sub.

8. The system of claim 6, wherein each of the tool subs comprises a support structure on which are mounted a corresponding microprocessor and initiator.

9. The system of claim 1, wherein the well tool further comprises explosives to be detonated by respective initiators.

10. The system of claim 1, wherein the link comprises a cable, the cable containing at least one of an electrical wire and a fiber optic line.

11. An apparatus comprising:

an initiator to initiate an explosive, wherein the initiator is selected from the group consisting of an exploding foil initiator (EFI), an exploding bridge wire (EBW), a semiconductor bridge (SCB), and a hot wire;

a control unit for use in a wellbore, the control unit adapted to be coupled to a link, the control unit comprising;

a switch; and

a microprocessor to interact with the switch to provide isolation of signaling on the link from the initiator until the microprocessor has established bi-directional communication with a controller.

12. The apparatus of claim 11, wherein the microprocessor is assigned a unique identifier.

13. The apparatus of claim 12, wherein the microprocessor is adapted to perform coded bi-directional communication with the controller.

14. The apparatus of claim 12, wherein the microprocessor is adapted to perform bi-directional communication with the controller according to a predetermined communication protocol.

15. The apparatus of claim 11, further comprising a sensor coupled to the microprocessor, the sensor to provide information relating to an environment of the wellbore.

16. The apparatus of claim 15, wherein the microprocessor is adapted to communicate the information from the sensor to the controller.

17. A method for use in a wellbore, comprising:

deploying a well tool into the wellbore;

communicating, over a link, between a controller and the well tool, wherein the well tool comprises plural control units, each of the plural control units having a microprocessor and an initiator coupled to the microprocessor; and

each microprocessor communicating bi-directionally with the controller,

the controller sending a plurality of activation commands to respective microprocessors to activate the respective control units, each activation command containing a unique identifier corresponding to a respective control unit.

18. The method of claim 17, further comprising providing a support structure in each control unit;

and mounting the microprocessor and initiator of each control unit on the support structure.

19. The method of claim 18, wherein mounting the microprocessor and initiator on the support structure comprises mounting the microprocessor and initiator on a flexible circuit.

20. The method of claim 18, wherein mounting the microprocessor and initiator on the support structure comprises mounting the microprocessor and initiator on a flex cable.

21. The method of claim 17, wherein mounting the initiator on the support structure comprises mounting at least one of an exploding foil initiator, an exploding bridge wire, a hot wire, and a semiconductor bridge on the support structure.