Electrical pulse drill bit having spiral electrodes

Patent metadata

Field	Value
Publication number	US-10370903-B2
Application number	US-201715410955-A
Country	US
Kind code	B2
Filing date	Jan 20, 2017
Priority date	Jan 20, 2016
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

Abstract

A drill bit assembly includes a drill bit body, an insulating layer disposed on an end of the drill bit body and that defines a drill bit face and two electrodes formed such that they both extend from the drill bit face. The two electrodes form a spiral on the drill bit face and are equidistant from each other at all locations of the drill bit face.

First claim

What is claimed is:

1. A drill bit assembly comprising:
a drill bit body;
an insulating layer disposed on an end of the drill bit body and that defines a drill bit face; and
two electrodes formed such that they both extend from the drill bit face, wherein a first electrode of the two electrodes forms a first spiral on the drill bit face and a second electrode of the two electrodes forms a second spiral on the drill bit face;
wherein a minimum distance between the first spiral and second spiral is identical at all locations along the first and second spirals.

2. The drill bit assembly of claim 1 , wherein the two electrodes form a bifilar coil when a discharge occurs between them.

3. The drill bit assembly of claim 1 , further comprising:
a pulse generator electrically coupled to the two electrodes.

4. The drill bit assembly of claim 3 , wherein the pulse generator causes the formation of a potential between the two electrodes.

5. The drill bit assembly of claim 4 , wherein the pulse generator causes the potential to be formed at a rise time that is below a threshold rise time.

6. The drill bit assembly of claim 5 , wherein the threshold rise time is less than a rise time where the potential will discharge through a fluid between the two electrodes.

7. The drill bit assembly of claim 5 , wherein the threshold rise time is equal to a rise time where the potential will discharge through a rock near or between the two electrodes.

8. The drill bit assembly of claim 4 , further comprising:
a power unit that provides power to the pulse generator.

9. The drill bit assembly of claim 8 , wherein the power unit is one of a battery, turbine or a mud motor.

10. The drill bit assembly of claim 1 , wherein the two electrodes also surround a radial outer surface of the insulating layer.

11. The drill bit assembly of claim 4 , wherein the pulse generator includes a switch that allows for the potential to be provided either end of the both electrodes.

12. A drill bit assembly comprising:
a drill bit body;
an insulating layer disposed around the drill bit body; and
two electrodes formed such that they both extend from a radial outer surface of the insulating layer, wherein a first electrode of the two electrodes forms a first helix on the radial outer surface and a second electrode of the two electrodes forms a second helix on the radial outer surface,
wherein a minimum distance between the first helix and the second helix is identical at all locations along the first and second helixes.

13. The drill bit assembly of claim 12 , wherein the two electrodes form a bifilar coil when a discharge occurs between them.

14. The drill bit assembly of claim 12 , further comprising:
a pulse generator electrically coupled to the two electrodes that causes the formation of a potential between the two electrodes.

15. The drill bit assembly of claim 14 , wherein the pulse generator causes the potential to be formed at rise time that is below a threshold rise time that is less than a rise time where the potential will discharge through a fluid between the two electrodes.

16. The drill bit assembly of claim 14 , wherein the pulse generator includes a toggle switch that allows for the potential to be provided either end of both electrodes.

17. A method of drilling a borehole comprising:
coupling a drill bit assembly to a drill string, the assembly comprising:
a drill bit body;
an insulating layer disposed on an end of the drill bit body and that defines a drill bit face;
two electrodes formed such that they both extend from the drill bit face, wherein a first electrode of the two electrodes forms a first a spiral on the drill bit face and a second electrode of the two electrodes forms a second spiral on the drill bit face and a minimum distance between the first spiral and second spiral is identical at all locations along the first and second spirals;
and
a pulse generator electrically coupled to the two electrodes;

forming a potential between the two electrodes by providing power to the pulse generator;
allowing the potential to discharge through a formation at or near the drill bit face; and
removing formation fragments from the borehole caused by the discharge.

18. The method of claim 17 , wherein the pulse generator causes the potential to be formed at a rise time that is below a threshold rise time.

19. The method of claim 18 , wherein the threshold rise time is less than a rise time where the potential will discharge through a fluid between the two electrodes.

20. The method of claim 18 , wherein the threshold rise time is equal to a rise time where the potential will discharge through a rock near or between the two electrodes.

21. The method of claim 17 , further comprising:
switching a configuration of a switch in the pulse generator to change a location where the pulse generator forms the potential between the two electrodes.

Assignees

• Lehr Joerg
• Anders Erik
• Baker Hughes A Ge Co Llc

Inventors

• Lehr Joerg
• Anders Erik

Classifications

• E21B7/15 Primary

  of electrically generated heat · CPC title

• E21B10/00

  Drill bits (specially adapted for deflecting the direction of boring {E21B7/064}; with means for collecting substances E21B27/00) · CPC title