Magnetic downhole tool and related subassemblies having mu-metallic shielding

Patent metadata

Field	Value
Publication number	US-2016369596-A1
Application number	US-201315039014-A
Country	US
Kind code	A1
Filing date	Dec 24, 2013
Priority date	Dec 24, 2013
Publication date	Dec 22, 2016
Grant date	—

Abstract

Systems and related methods are disclosed that involve the use of a magnetic downhole assembly or a magnetic downhole tool. The assembly and tool include a mu-metal sleeve that is operable to isolate a magnetic field and a permanent magnet disposed within the mu-metal sleeve. The assembly and tool also include an actuator that is operable to selectively extend and retract the sleeve to alternatingly expose and shield the permanent magnet. A conveyance is operable to deploy the magnetic downhole assembly and tool to a selected location within a wellbore and a controller is communicatively coupled to the actuator and operable to generate a control signal that causes the actuator to extend or retract the permanent magnet from the mu-metal sleeve.

First claim

We claim:

1 . A system of operating a magnetic downhole assembly comprising:
a magnetic downhole assembly having a shielding sleeve operable to isolate a magnetic field, a permanent magnet disposed within the shielding sleeve, and an actuator, the actuator being operable to selectively extend and retract the sleeve to selectively expose and shield the permanent magnet; a conveyance operable to deploy the magnetic downhole assembly to a selected location within a wellbore; and a controller communicatively coupled to the actuator and operable to generate a control signal.

2 . The system of claim 1 , wherein the shielding sleeve comprises a mu-metal.

3 . The system of claim 1 , wherein the actuator is selected from the group consisting of a hydraulic actuator, an electric actuator, and a mechanical actuator.

4 . The system of claim 1 , further comprising:
a tubing segment having a fluid flow path therethrough; a reservoir coupled to the controller and having a magnetorheological fluid disposed therein, the reservoir being operable to disperse the magnetorheological fluid into the fluid flow path in response to the control signal.

5 . The system of claim 4 , further comprising a pressure sensor coupled to the controller, wherein the magnetic downhole assembly is operable to extend the permanent magnet adjacent the fluid flow path to generate a magnetic field across the fluid flow path in response to the control signal, and wherein the controller is operable to generate the control signal in response to determining that a pressure at the pressure sensor is increasing at a rate that is greater than a predetermined rate.

6 . The system of claim 1 , further comprising a tubing segment and a reservoir coupled to the controller, wherein the reservoir comprises a magnetorheological fluid disposed therein, and wherein the reservoir is operable to disperse the magnetorheological fluid adjacent the magnetic downhole assembly between an exterior surface of the tubing segment and a wellbore wall in response to the control signal.

7 . The system of claim 6 , wherein the magnetic downhole assembly is operable to extend the permanent magnet to generate a magnetic field about the external exterior surface of the tubing segment in response to the control signal.

8 . A magnetic downhole tool comprising:
a mu-metal sleeve operable to isolate a magnetic field; a permanent magnet disposed within the mu-metal sleeve; and an actuator, the actuator being operable to selectively extend and retract the sleeve to selectively expose and shield the permanent magnet.

9 . The magnetic downhole tool of claim 8 , wherein the mu-metal sleeve comprises a plurality of layers of mu-metal.

10 . The magnetic downhole tool of claim 9 , wherein the layers of mu-metal are separated by at least one insulating layer.

11 . The magnetic downhole tool of claim 21 , wherein the actuator is selected from the group consisting of a hydraulic actuator, a solenoid, and a mechanical actuator.

12 . A method of operating a magnetic downhole tool, the method comprising:
providing a magnetic downhole tool comprising a mu-metal sleeve operable to isolate a magnetic field, a permanent magnet disposed within the mu-metal sleeve, and an actuator, the actuator being operable to selectively extend and retract the sleeve to selectively expose and shield the permanent magnet; providing a controller, the controller being communicatively coupled to the actuator; and generating a control signal to cause the actuator to extend or retract the metal sleeve.

13 . The method of claim 12 , wherein the mu-metal comprises a nickel-iron alloy.

14 . The method of claim 12 , wherein the step of generating the control signal is selected from the group consisting of generating a hydraulic control signal, generating an electric control signal, and generating a mechanical control signal.

15 . The method of claim 12 , further comprising coupling the magnetic downhole tool to a conveyance and positioning the downhole tool at a selected location in a wellbore, wherein the conveyance is selected from the group consisting of a slickline, a wireline, and a tool string.

16 . The method of claim 12 , further comprising exposing the permanent magnet to control the viscosity of a magnetorheological fluid.

17 . The method of claim 12 , further comprising exposing the permanent magnet to remove a plug from a wellbore casing.

18 . The method of claim 12 , further comprising exposing the permanent magnet and manipulating the magnetic downhole tool to adjust the position of a screen.

19 . The method of claim 12 , further comprising exposing the permanent magnet and manipulating the magnetic downhole tool to adjust the position of a second downhole tool.

20 . The method of claim 12 , further comprising exposing the permanent magnet to couple permanent magnet to a second downhole tool, delivering the second downhole tool to a selected location, and retracting the permanent magnet.

Assignees

• Halliburton Energy Services Inc

Inventors

• Mcmillon Christopher Michael
• Neely Robert Mitchell

Classifications

• E21B41/00 Primary

  Equipment or details not covered by groups E21B15/00 - E21B40/00 · CPC title

• E21B43/08

  Screens or liners {(expandable screens or liners E21B43/108)} · CPC title

• E21B23/00

  Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells (setting of casings, screens or liners E21B43/10) · CPC title

• E21B31/06

  using magnetic means · CPC title

• E21B33/12

  Packers; Plugs (used for cementing E21B33/134, E21B33/16) · CPC title