Wellbore gun perforating system and method

Patent metadata

Field	Value
Publication number	US-10408024-B2
Application number	US-201715831054-A
Country	US
Kind code	B2
Filing date	Dec 4, 2017
Priority date	Feb 20, 2015
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A wellbore perforating system and method with reliable and safer connections in a perforating gun assembly is disclosed. The system/method includes a gun string assembly (GSA) deployed in a wellbore with multiple perforating guns attached to plural switch subs. The perforating guns are pre-wired with a cable having multi conductors; the multi conductors are connected to electrical ring contacts on either end of the perforating guns. The switch subs are configured with electrical contacts that are attached to the electrical contacts of the perforating guns without the need for manual electrical connections and assembly in the field of operations. The system further includes detonating with a detonator that is positioned upstream of the perforating gun. The detonator is wired to a switch that is positioned downstream of the perforating gun.

First claim

What is claimed is:

1. A perforating gun system comprising:
a perforating gun with an upstream end and a downstream end;
a first switch sub connected to the downstream end of the perforating gun, wherein the first switch sub comprises a first switch and a first detonator;
a second switch sub connected to the upstream end of the perforating gun, wherein the second switch sub comprises a second switch and a second detonator; and
wherein the first switch selectively completes an electrical connection with the second detonator.

2. The perforating gun system of claim 1 , wherein the second detonator in the second switch sub is disarmed until the second switch sub is electrically connected to the first switch sub through the perforating gun.

3. The perforating gun system of claim 2 , wherein the second switch sub first switch sub is electrically connected to the when the first switch selectively completes the electrical connection with the second detonator.

4. The perforating gun system of claim 1 , wherein said second detonator is only armed when the first switch selectively completes the electrical connection with the second detonator.

5. The perforating gun system of claim 1 , further comprising:
a second perforating gun connected to the first switch sub through a downstream adapter in the first switch sub.

6. The perforating gun of claim 5 , wherein the first switch sub further comprises an upstream adapter electrically connected to the downstream adapter and the detonator to form a slidably removable cartridge.

7. The perforating gun system of claim 1 , wherein the perforating gun is connected to the downstream end of the second switch sub through a downstream adapter in the second switch sub.

8. A wellbore perforating method comprising:
providing a gun system comprising at least a first perforating gun, a first switch sub, a second perforating gun, and a second switch sub; wherein the first perforating gun, the first switch sub, the second perforating gun, and the second switch sub are connected in series;
activating a first switch in the first switch sub in response to firing a first detonator in the first switch sub, wherein activating the first switch arms a second detonator in the second switch sub; and
electrically connecting, in the first switch, a through-wire and a fire wire.

9. The wellbore perforating method of claim 8 , wherein the first switch is a pressure switch, and wherein activating the first switch comprises:
capturing a blasting event from a detonation of the first detonator.

10. A switch sub comprising:
an upstream adapter positioned at an upstream end of the switch sub, wherein the upstream adapter comprises a first plurality of electrical contacts;
a downstream adapter positioned at a downstream end of the switch sub, wherein the downstream adapter comprises an exterior surface area facing a well, a base area facing a perforating gun, and a second plurality of electrical contacts formed on the exterior surface area; and
a plurality of conducting elements extending through the switch sub from the upstream end to the downstream end, wherein one of the first plurality of contacts is connected to one of the second plurality of contacts by one of the plurality of conducting elements,
wherein the downstream adapter, which is positioned at the downstream end of the switch sub, has a chamber configured to hold a detonator.

11. The switch sub of claim 10 , wherein the plurality of electrical contacts further comprises a through wire contact, a ground wire contact, and a power wire contact.

12. The switch sub of claim 10 , wherein the upstream adapter has a first size, and wherein the downstream adapter has a second size that is different from the first size.

13. The switch sub of claim 12 , wherein the downstream adapter is configured to be electrically connected directly to an upstream end of a downstream perforating gun, and wherein the upstream adapter is configured to be electrically connected directly to a downstream end of an upstream perforating gun.

14. The switch sub of claim 10 , wherein the plurality of conducting elements is a conducting rod, a through-wire, or combinations thereof.

15. The switch sub of claim 10 , wherein the downstream adapter holds the detonator at the downstream end.

16. The switch sub of claim 15 , wherein the downstream adapter is configured to accept a switch at an opposite end, and wherein the switch is connected to the detonator through the downstream adapter.

17. The switch sub of claim 10 , wherein the upstream adapter, the downstream adapter and the detonator are electrically connected to form a slidably removable cartridge.

18. The switch sub of claim 17 , wherein the switch sub comprises a cavity in communication with an aperture at one end, wherein the cavity and the aperture are sized to receive the slidably removable cartridge.

19. The switch sub of claim 10 , wherein the detonator is wired to two contacts of the second plurality of electrical contacts of the downstream adapter.

20. The switch sub of claim 10 , wherein the second plurality of electrical contacts are formed as contact rings around the exterior surface area of the downstream adapter.

Assignees

• Geodynamics Inc

Inventors

• Hardesty John T

Classifications

• F42D1/05

  Electric circuits for blasting · CPC title

• E21B43/117

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

• E21B43/116

  Gun or shaped-charge perforators · CPC title

• E21B43/1185 Primary

  Ignition systems · CPC title

• F42D1/045

  Arrangements for electric ignition (dynamo-electric generators H02K) · CPC title