Induction Logging Sensor

• US 20150115965A1
• Filed: 10/23/2014
• Published: 04/30/2015
• Est. Priority Date: 10/24/2013
• Status: Active Grant

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Reiderman, Arcady, Forgang, Stanislav W., Morris, Steven A., Hook, Jonathan F., Liu, Yi
• Granted Patent: US 9,880,307 B2
• Time in Patent Office: Days
• US Class Current: 324/339
• CPC Class Codes: E21B 47/0228 using electromagnetic energy or detectors therefor
• CPC Class Codes: E21B 47/092 by detecting magnetic anomalies
• CPC Class Codes: E21B 47/113 using electrical indications; using light radiations
• CPC Class Codes: G01V 3/10 using induction coils
• CPC Class Codes: G01V 3/104 using several coupled or uncoupled coils G01V3/101 takes precedence
• CPC Class Codes: G01V 3/20 operating with propagation of electric current
• CPC Class Codes: G01V 3/30 operating with electromagnetic waves

Abstract

Apparatuses and methods are provided herein that may improve sensitivity to transient signals. For example, an electromagnetic sensor for downhole measurements that includes a plurality of sectors (e.g., four quadrants) is provided herein. Each quadrant may include a magnetic core formed of a material with a high initial magnetic permeability to improve sensitivity to transient signals. A sensor for continuous wave induction tools is also provided, and may include a magnetic core formed of a material with a high initial magnetic permeability. Forming each sector magnetic core of a material with a high mechanical reliability may allow the magnetic core of the corresponding sensor to be pliable and flexible and not brittle and prone to breaking. Furthermore, the corresponding sensor may have enhanced sensitivity, greater stability of sensitivity relative to temperature changes, and high mechanical reliability.

Claims

1. An apparatus, comprising:

an electromagnetic sensor comprising a plurality of sectors, wherein each sector comprises a magnetic core formed of a material having a high initial magnetic permeability, the material comprising at least one of a nano-magnetic material, a nano-magnetic ribbon material, a nano-crystalline material, an amorphous ribbon, or a non-ferrite material.

2. The apparatus of claim 1, wherein the electromagnetic sensor has at least one of the following properties:

a high temperature stability and a high mechanical reliability.

3. The apparatus of claim 1, wherein the electromagnetic sensor comprises an induction logging sensor, a single axis sensor, or a multi-axial sensor.

4. The apparatus of claim 1, wherein each sector further comprises at least one coil wound around a portion of the magnetic core thereof.

5. The apparatus of claim 1, wherein at least one of the plurality of sectors further comprises two coils wound, in respective directions orthogonal to one another, around portions of the magnetic core thereof.

6. The apparatus of claim 5, further comprising a shield disposed between the two coils.

7. The apparatus of claim 1, wherein, for each sector, the material forming the magnetic core thereof has a relative magnetic permeability in a range of 10,000 to 20,000.

8. The apparatus of claim 1, wherein the plurality of sectors is selected from the group consisting of:

two semicircles, four quadrants, six sextants, eight octants, a plurality of sectors of equal sizes, and a plurality of sectors including at least two sectors of unequal size.

9. The apparatus of claim 1, wherein, for each sector, the magnetic core comprises a plurality of subsections coupled together by a non-conductive material.

10. A method of manufacturing an electromagnetic sensor, comprising:

creating a magnetic core from at least one layer of a material having a high initial magnetic permeability, the material comprising at least one of a nano-magnetic material, a nano-magnetic ribbon material, a nano-crystalline material, an amorphous ribbon, or a non-ferrite material; and

separating the magnetic core into a plurality of portions, wherein the portions can be used to form a plurality of sectors of the electromagnetic sensor.

11. The method of claim 10, wherein the sensor has at least one of the following properties:

a high temperature stability and a high mechanical reliability.

12. The method of claim 10, further comprising winding at least one coil around each portion of the magnetic core to produce a sector for the electromagnetic sensor.

13. The method of claim 10, wherein creating the magnetic core comprises adhering a plurality of layers of nano-magnetic ribbon material together with a non-conductive epoxy.

14. The method of claim 10, further comprising, for each sector, dividing the core into a plurality of subsections and coupling the subsections together with a nonconductive material.

15. The method of claim 10, wherein the plurality of sectors is selected from the group consisting of:

two semicircles, four quadrants, six sextants, eight octants, a plurality of sectors of equal sizes, and a plurality of sectors including at least two sectors of unequal size.

16. A method, comprising:

providing a logging tool comprising a sensor, the sensor comprising a plurality of sectors, wherein each sector comprises a magnetic core formed of a material having a high initial magnetic permeability, the material comprising at least one of a nano-magnetic material, a nano-magnetic ribbon material, a nano-crystalline material, an amorphous ribbon, or a non-ferrite material;

disposing the logging tool within a wellbore; and

performing a transient induction measurement using the logging tool.

17. The method of claim 16, wherein the sensor has at least one of the following properties:

a high temperature stability and a high mechanical reliability.

18. The method of claim 16, wherein each sector further comprises at least one coil wound around a portion of the magnetic core thereof.

19. The method of claim 16, wherein, for each sector, the magnetic core comprises a plurality of subsections coupled together by a non-conductive material.

20. The method of claim 16, wherein, for each sector, the magnetic core comprises a plurality of layers of nano-magnetic ribbon material adhered together with a non-conductive epoxy.