PERFORATING GUN WITH ECCENTRIC ROTATABLE CHARGE TUBE

• US 20150226044A1
• Filed: 02/12/2015
• Published: 08/13/2015
• Est. Priority Date: 02/12/2014
• Status: Active Grant

• Current Assignee: Owen Oil Tools LP (Core Laboratories NV)
• Original Assignee: Owen Oil Tools LP (Core Laboratories NV)
• Inventors: LaGrange, Timothy E., Ursi, Jeremy, Antal, Brian, Hollis, William D.
• Granted Patent: US 9,903,185 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E21B 43/117 Shaped-charge perforators E21B43/118 takes precedence
• CPC Class Codes: E21B 43/119 Details, e.g. for locating perforating place or direction

Abstract

A perforating gun includes an orienting device retained in a carrier and a charge tube rotatably connected to the orienting device. The orienting device misaligns a center axis of the charge tube with a different second axis such that gravity can cause the charge tube to rotate about the different second axis. The charge tube does not rotate about the center axis of the charge tube while the charge tube rotates about the different second axis.

Claims

1. A perforating gun, comprising:

a carrier;

a charge tube disposed inside the carrier;

a plurality of shaped charges positioned along the charge tube; and

at least one orienting device positioned on each opposing end of the charge tube, wherein each orienting device includes;

an end plate retained in the carrier;

a decentralizer fixed to the charge tube, wherein the decentralizer includes a cylindrical hub and a cylindrical mandrel, and wherein a center axis of the hub and a center axis of the mandrel are eccentrically aligned; and

a bearing rotatably connecting the decentralizer to the end plate, wherein the decentralizer rotates relative to the end plate.

2. The perforating gun of claim 1, wherein the charge tube is fixed to the mandrel.

3. The perforating gun of claim 2, wherein a center axis of the charge tube aligns with the center axis of the mandrel.

4. The perforating gun of claim 1, wherein the center axis of the hub is a center axis of at least one of:

(i) the carrier, (ii) the end plate, and (iii) the bearing, and the center axis of the mandrel aligns with the center axis of the charge tube.

5. The perforating gun of claim 1, wherein the endplate is a ring shaped member having a bore in which the bearing is received, and wherein the bearing has a bore in which the hub is received.

6. The perforating gun of claim 1, wherein the mandrel is telescopically connected to the charge tube and wherein a bore extends through the mandrel and the hub.

7. The perforating gun of claim 1, further comprising a connector assembly associated with the at least one orienting device, the at least one connector assembly including a housing, an electrical assembly fixed to the housing, and a contact tube rotatably connected to the electrical assembly and fixed to the decentralizer.

8. The perforating gun of claim 7, further comprising a first energetic component in the housing and a second energetic component in the contact tube.

9. The perforating gun of claim 8, wherein the first energetic component includes at least one of:

(i) a detonator cord, (ii) a detonator, (iii) a booster charge, and (iv) an energetic material and the second energetic component includes at least one of;

(i) a detonator cord, (ii) a detonator, (iii) a booster charge, and (iv) an energetic material.

10. The perforating gun of claim 1, further comprising:

(i) at least one weight positioned along the charge tube, and (ii) at least one support positioned along the charge tube.

11. A perforating gun, comprising:

a carrier; and

an orienting device connected to the carrier, wherein the orienting device misaligns a center axis of the carrier with a different second axis, and wherein gravity causes the charge tube to rotate about the different second axis while the carrier does not rotate about the center axis of the carrier.

12. The perforating gun of claim 11, wherein the orienting device includes at least one external roller;

and further comprising a rotational decoupler connecting the carrier to a coiled tubing string.

13. The perforating gun of claim 12, wherein the at least one external roller includes opposing pins that project from a collar, and wherein the carrier includes a box connecting to each pin, and wherein the collar includes a plurality of roller elements that are distributed on a circumferential face, wherein the roller elements are configured to contact an inner surface of a wellbore tubular, and wherein the carrier and the collar are fixed to one another and rotate in unison.

14. The perforating gun of claim 13, wherein an axis of the carrier is decentralized relative to the axis of the collar to cause an eccentricity of sufficient distance to allow gravity to rotate the carrier relative to the wellbore tubular when the carrier is in a non-vertical alignment.

15. The perforating gun of claim 14, wherein the pins are positioned eccentric relative to an axis of the collar.