Torsion resistant gap sub

Patent metadata

Field	Value
Publication number	US-11686159-B2
Application number	US-202117445561-A
Country	US
Kind code	B2
Filing date	Aug 20, 2021
Priority date	Aug 14, 2015
Publication date	Jun 27, 2023
Grant date	Jun 27, 2023

Abstract

A gap sub assembly for electromagnetic telemetry used in downhole drilling. The gap sub comprises a female part comprising a female mating section and a male part comprising a male mating section. The male mating section is matingly received within the female mating section and electrically isolated therefrom. One or more electrically insulating bodies secure the male part axially and torsionally relative to the female part. The electrically insulating bodies also electrically isolate the male part from the female part. The electrically insulating bodies can be installed through apertures in the female part or at least some of the electrically insulating bodies can be installed before the male mating section is inserted into the female mating section. The electrically insulating bodies can be held in place on the male mating section using a retention apparatus such as a ring, a scarf, pods or an adhesive.

First claim

What is claimed is:

1. A gap sub comprising:
a female part having a female mating section;
a male part electrically isolated from the female part, the male part having a male mating section and a gap section, the male mating section being inserted into a bore of the female mating section whereby the male and female mating sections overlap in an axial direction and are spaced radially apart from one another to provide a radial gap between the male and female mating sections wherein surfaces of the male and female mating sections facing one another across the radial gap comprise grooves, grooves on the surface of the male mating section corresponding to grooves on the surface of the female mating section, forming pairs of corresponding grooves;
an electrically insulating collar positioned on the gap section; and
a plurality of electrically-insulating bodies located between the overlapping male and female mating sections and spanning between each pair of corresponding grooves in the surfaces of the male and female mating sections such that the male and female parts are mechanically coupled together;
wherein the surfaces of the male and female mating sections are formed such that opposing edges of grooves of at least one pair of corresponding grooves have different elevations; and
wherein, for the at least one pair of corresponding grooves, a higher edge of the groove on the male mating section is radially outward relative to a higher edge of the corresponding groove on the female mating section.

2. A gap sub according to claim 1 , wherein a centroid of at least one of the bodies that spans between the at least one pair of corresponding grooves is radially between the higher edge of the groove on the male mating section and the higher edge of the groove on the female mating section.

3. A gap sub according to claim 1 , wherein, for at least one pair of corresponding grooves the higher edge and a lower edge of the groove on the male mating section are respectively radially aligned with a lower edge and the higher edge of the corresponding groove on the female mating section.

4. A gap sub according to claim 1 , wherein the bodies comprise spherical balls.

5. A gap sub according to claim 1 , wherein the bodies are cylindrical.

6. A gap sub according to claim 1 , wherein the bodies comprise elongated rods.

7. A gap sub according to claim 6 , wherein the rods are segmented.

8. A gap sub according to claim 6 , wherein the rods are non-circular in cross-section.

9. A gap sub according to claim 8 , wherein the rods are polygonal in cross section.

10. A gap sub according to claim 1 , wherein at least one pair of corresponding grooves extends substantially longitudinally along the gap sub.

11. A gap sub according to claim 10 , wherein higher and lower edges of the longitudinal grooves on the male mating section are arranged such that, for two adjacent grooves, the higher edges are adjacent or the lower edges are adjacent.

12. A gap sub according to claim 10 , wherein higher and lower edges of the longitudinal grooves on the male mating section are arranged such that, for two adjacent grooves, the higher edge of one of the adjacent grooves is adjacent to the lower edges of the other groove.

13. A gap sub according to claim 1 , wherein at least one of the pairs of corresponding grooves comprise pockets formed in one wall of one of the grooves, the pockets shaped to conform with a shape of the bodies.

14. A gap sub according to claim 1 , wherein a bottom surface of at least one of the corresponding grooves is arcuate.

15. A gap sub according to claim 1 , wherein at least one of the corresponding grooves is V-shaped in cross section.

16. A gap sub according to claim 1 , comprising a longitudinal bore extending through the gap sub and threaded couplings on opposing ends of the gap sub.

17. A gap sub according to claim 16 , wherein one of the threaded couplings is a pin coupling comprising a first thread and one of the threaded couplings is a box coupling comprising a second thread.

18. A gap sub comprising:
a female part having a female mating section;
a male part electrically isolated from the female part, the male part having a male mating section and a gap section, the male mating section being inserted into a bore of the female mating section whereby the male and female mating sections overlap in an axial direction and are spaced radially apart from one another to provide a radial gap between the male and female mating sections wherein surfaces of the male and female mating sections facing one another across the radial gap comprise grooves, the grooves on the surface of the male mating section corresponding to the grooves on the surface of the female mating section, forming pairs of corresponding grooves;
an electrically insulating collar positioned on the gap section; and
a plurality of electrically-insulating bodies located between the overlapping male and female mating sections and spanning between each pair of corresponding grooves in the surfaces of the male and female mating sections such that the male and female parts are mechanically coupled together;
wherein at least one of the surfaces of the male and female mating sections is formed such that opposing edges of at least one of the corresponding grooves have different elevations; and
wherein at least one groove of at least one of the pairs of corresponding grooves comprises spherical cups formed in one wall of the at least one groove, the shape of the bodies shaped to conform with the spherical cups.

19. A gap sub comprising:
a female part having a female mating section;
a male part electrically isolated from the female part, the male part having a male mating section and a gap section, the male mating section being inserted into a bore of the female mating section whereby the male and female mating sections overlap in an axial direction and are spaced radially apart from one another to provide a radial gap between the male and female mating sections wherein surfaces of the male and female mating sections facing one another across the radial gap comprise grooves, the grooves on the surface of the male mating section corresponding to the grooves on the surface of the female mating section, forming pairs of corresponding grooves;
an electrically insulating collar positioned on the gap section; and
a plurality of electrically-insulating bodies located between the overlapping male and female mating sections and spanning between each pair of corresponding grooves in the surfaces of the male and female mating sections such that the male and female parts are mechanically coupled together;
wherein at least one of the surfaces of the male and female mating sections is formed such that opposing edges of at least one of the corresponding grooves have different elevations; and
wherein, at least one body of the plurality of bodies projects more deeply into the respective groove than into the respective corresponding groove of one of the pairs of corresponding grooves.

20. A gap sub according to claim 19 , wherein the body projects more deeply into the respective groove on the male mating section than into the respective corresponding groove on the female mating section.

Assignees

• Evolution Engineering Inc

Inventors

• Stack Luke A
• Logan Aaron W
• Logan Justin C
• Kazemi Miraki Mojtaba
• Derkacz Patrick R
• Lee Gavin Gaw-Wae
• Hepguvendik Hasan Alper
• Ahmoye Daniel W
• Francoeur Angelica J B

Classifications

• E21B17/028

  Electrical or electro-magnetic connections · CPC title

• E21B17/003 Primary

  with electrically conducting or insulating means (E21B17/028 and E21B17/023 take precedence) · CPC title

• E21B17/0426

  with a threaded cylindrical portion, e.g. for percussion rods · CPC title

• F16L25/01

  specially adapted for realising electrical conduction between the two pipe ends of the joint or between parts thereof · CPC title

• H01B3/12

  ceramics · CPC title