Tandem sub for self-orienting perforating system

Patent metadata

Field	Value
Publication number	US-12228019-B2
Application number	US-202418604435-A
Country	US
Kind code	B2
Filing date	Mar 13, 2024
Priority date	Jan 21, 2022
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

A method and apparatus for using a tandem sub to connect one or more perforating gun assemblies, having a rotational bearing mechanism lining the inner diameter in both ends to allow the charge tube assembly to rotate within the gun body.

First claim

What is claimed is:

1. A method for using a tandem sub for connecting one or more perforating gun assemblies, comprising:
providing a tandem sub with a first rotational mechanism at a first end, and a second rotational mechanism at a second end,
coupling the first end to a first perforating gun with a first charge tube, wherein the first rotational mechanism engages the first charge tube in a first perforating gun allowing the first charge tube to rotate freely;
coupling the second end to a second perforating gun with a second charge tube, wherein the second rotational mechanism engages with a second charge tube in a second perforating gun allowing the second charge tube to rotate freely.

2. The method of claim 1 further comprising feeding an electrical connection through a bulkhead installed within a through passage in the tandem sub, wherein the feed through bulkhead provides an electric contact between the first perforating gun and the second perforating gun while further providing a pressure seal between the first perforating gun and the second perforating gun.

3. The method of claim 2 further comprising coupling a first retainer to the first rotation mechanism, wherein the first retainer retains and protects the first rotational mechanism.

4. The method of claim 3 further comprising coupling a second retainer to the second rotation mechanism, wherein the second retainer retains and protects the first rotational mechanisms.

5. The method of claim 1 wherein the first rotation mechanism is a needle bearing.

6. The method of claim 1 wherein the second rotation mechanism is a needle bearing.

7. The method of claim 1 wherein the first and second charge tubes are weighted to facilitate self-orientation based on gravity in a horizontal wellbore.

8. The method of claim 1 , further including coupling a first top end fitting of the first charge tube to the first rotational bearing mechanism, wherein the first top end fitting is made of a non-conductive material to isolate electrical components from the surrounding metallic structure.

9. The method of claim 8 , further including coupling a second top end fitting of the second charge tube to the second rotational bearing mechanism, wherein the second top end fitting is made of a non-conductive material to isolate electrical components from the surrounding metallic structure.

10. A method for connecting and orienting one or more perforating gun assemblies in a subterranean well, comprising:
providing a tandem sub including a first rotational bearing mechanism located at a first end and a second rotational bearing mechanism located at a second end, each rotational bearing mechanism adapted to engage with a charge tube in respective perforating guns and allow the charge tubes to rotate freely;
attaching a first perforating gun to the first end of the tandem sub, wherein the first perforating gun includes a first charge tube that engages with the first rotational bearing mechanism;
attaching a second perforating gun to the second end of the tandem sub, wherein the second perforating gun includes a second charge tube that engages with the second rotational bearing mechanism;
securing an outer tandem housing of the tandem sub to engage with outer gun housings of the first and second perforating guns; and
facilitating electrical continuity and providing a pressure seal between the first and second perforating guns through a feed-through bulkhead installed within a through passage of the tandem sub.

11. The method of claim 10 , wherein the first and second rotational bearing mechanisms are needle bearings designed to facilitate the free rotation of the charge tubes while maintaining alignment within the perforating guns.

12. The method of claim 10 , further comprising aligning the first charge tube and the second charge tube with respective perforating charges within the first and second perforating guns to ensure targeted perforation aligned with the reservoir formation.

13. The method of claim 10 , wherein attaching the first and second perforating guns to the tandem sub includes screwing threaded connections between the tandem sub and the perforating guns to secure the assembly without rotation of the connected components relative to each other.

14. The method of claim 10 , further comprising installing a feed-through bulkhead within the through passage of the tandem sub to establish electrical continuity between the first and second perforating guns and to provide a pressure seal between the interconnected perforating guns.

15. The method of claim 14 , wherein the feed-through bulkhead includes an electrical contact that protrudes outward, facilitating an electrical connection between the first and second perforating guns while maintaining the pressure integrity of the assembly.

16. The method of claim 10 , further including the step of coupling a top end fitting of the first charge tube to the first rotational bearing mechanism, wherein the top end fitting is made of a non-conductive material to isolate electrical components from the surrounding metallic structure.

17. The method of claim 16 , wherein the method further comprises establishing an electrical connection from the top end fitting through a wired connection to a controller switch housed within the top end fitting, thereby integrating control over the perforating gun firing sequence.

18. The method of claim 17 , wherein the method includes extending a through wire from the controller switch along the length of the first charge tube, connecting to an electrical contact on a bottom end fitting, enabling electrical actuation of the perforating charges.

19. The method of claim 10 , wherein the first and second charge tubes are weighted to facilitate self-orientation based on gravity, ensuring that the perforating charges are directed towards the intended section of the surrounding formation.

20. The method of claim 10 , including electrically connecting a plurality of gun assemblies in series having a plurality of tandem subs utilizing rotational bearing mechanisms.

Assignees

• Hunting Titan Inc

Inventors

• Bradley Ryan
• Veliz Julio Cesar

Classifications

• E21B43/117

  Shaped-charge perforators (E21B43/118 takes precedence) · CPC title

• F42B3/02

  adapted to be united into assemblies · CPC title

• F42B3/103 Primary

  Mounting initiator heads in initiators; Sealing-plugs · CPC title

• E21B43/119 Primary

  Details, e.g. for locating perforating place or direction · CPC title