Wellbore gun perforating system and method

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.

Claims

1. A cartridge to be placed in a sub, the cartridge comprising: a first electrical contact placed on a first end of the cartridge and configured to close an electrical circuit formed through a perforating gun; a detonator; a retaining member configured to attach to a sub; a switch connected to the detonator; and a second electrical contact electrically connected to the switch and placed at a second end of the cartridge, which is opposite to the first end, wherein the entire cartridge is configured to be received by sliding into the sub and attached to the sub with the retaining member.

2. The cartridge of claim 1, wherein the first electrical contact directly communicates with an electrical contact from a perforating gun that is attached to the sub.

3. The cartridge of claim 1, wherein the detonator is configured to ballistically communicate with a detonating cord placed in the perforating gun.

4. The cartridge of claim 1, wherein the switch is a pressure switch.

5. The cartridge of claim 1, wherein the switch is an electronic switch.

6. The cartridge of claim 1, wherein the switch is configured to arm a detonator located in another cartridge.

7. The cartridge of claim 1, wherein the first electrical contact extends outside the cartridge.

8. The cartridge of claim 1, wherein the second electrical contact extends outside the cartridge.

9. The cartridge of claim 1, wherein the detonator is entirely located inside an adapter of the cartridge.

10. A single switch sub comprising: a sub body having a bore that extends from a first end to a second end of the sub body; and a cartridge configured to partially slide into the bore of the sub body, wherein the cartridge comprises: a first electrical contact placed on a first end of the cartridge and configured to close an electrical circuit formed through a perforating gun that is attached to the switch sub, a detonator, a retaining member configured to attach to the switch sub, a switch connected to the detonator, and a second electrical contact electrically connected to the switch and placed at a second end of the cartridge, which is opposite to the first end, wherein the cartridge is configured to attach to the sub with the retaining member.

11. The switch sub of claim 10, wherein the first electrical contact directly communicates with an electrical contact from the perforating gun that is attached to the switch sub.

12. The switch sub of claim 10, wherein the detonator is configured to ballistically communicate with a detonating cord placed in the perforating gun.

13. The switch sub of claim 10, wherein the switch is a pressure switch.

14. The switch sub of claim 10, wherein the switch is an electronic switch.

15. The switch sub of claim 10, wherein the switch is configured to arm a detonator located in another switch sub.

16. The switch sub of claim 10, wherein the first electrical contact extends outside the cartridge.

17. The switch sub of claim 10, wherein the second electrical contact extends outside the cartridge.

18. The switch sub of claim 10, wherein the detonator is entirely located inside the cartridge.

19. The switch sub of claim 10, wherein the sub body is configured to directly attach to the perforating gun.

20. The switch sub of claim 10, wherein the second electrical contact includes plural individual electrical contacts.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a fuller understanding of the advantages provided by the invention, reference should be made to the following detailed description, together with the accompanying drawings, wherein:

(2) FIG. 1 illustrates a system block overview diagram for how prior art systems use gun string assemblies to perforate isolated fracturing zones.

(3) FIG. 2 illustrates a prior art perforating gun assembly with switch subs.

(4) FIG. 3 illustrates a flowchart describing how prior art systems assemble perforating guns with switch subs.

(5) FIG. 4 illustrates a flowchart describing how prior art systems perforate hydrocarbon formations with perforating guns and switch subs.

(6) FIG. 5 illustrates an exemplary front cross section of a pre-wired perforating gun with a multi conductor single cable according to a preferred embodiment of the present invention.

(7) FIG. 5a illustrates an exemplary clip to hold a multi conductor single cable according to a preferred embodiment of the present invention.

(8) FIG. 6 illustrates an exemplary perspective view of a pre-wired perforating gun with a multi conductor single cable according to a preferred embodiment of the present invention.

(9) FIG. 7 illustrates a front section view of a pre-wired perforating gun with electrical contacts integrated to a switch sub with electrical contacts, depicting a preferred embodiment of the present invention.

(10) FIG. 8 illustrates a perspective view of a pre-wired perforating gun with electrical contacts integrated to a switch sub with electrical contacts, depicting a preferred embodiment of the present invention.

(11) FIG. 9 illustrates an exemplary electrical connection diagram between a perforating gun, detonator and a switch sub depicting a preferred embodiment of the present invention.

(12) FIG. 10 illustrates an exemplary flowchart to assemble perforating guns with switch subs according to a presently preferred embodiment of the present invention.

(13) FIG. 11 illustrates a detailed flowchart of a wellbore perforation method according to a preferred exemplary invention embodiment.

(14) FIG. 12 illustrates a detailed flowchart of a wellbore perforation sequence method according to a preferred exemplary invention embodiment.

(15) FIG. 13 illustrates an exemplary front section view of a 2 part switch sub with no port with a detonator depicting a presently preferred embodiment of the present invention.

(16) FIG. 14 illustrates an exemplary perspective view of a 2 part switch sub with no port with a detonator depicting a presently preferred embodiment of the present invention.

DESCRIPTION OF THE PRESENTLY PREFERRED EXEMPLARY EMBODIMENTS

(17) While this invention is susceptible to embodiment in many different forms, there are shown in the drawings and will herein be described in detail a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiment illustrated.

(18) The numerous innovative teachings of the present application will be described, with particular reference to the presently preferred embodiment, wherein these innovative teachings are advantageously applied to the particular problems of a wellbore gun perforating system and method. However, it should be understood that this embodiment is only one example of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily limit any of the various claimed inventions. Moreover, some statements may apply to some inventive features, but not to others.

(19) It should be noted that the term “downstream” is used to indicate a position that is closer to the toe end of the wellbore casing, and term “upstream” is used to indicate a position that is closer to the heel end of the wellbore casing. The term “fire wire” or “arming wire” is used to indicate an input that is electrically connected to a detonator. The term “through wire” is used to indicate a conducting electrical wire that is part of a wireline cable that is connected to a gun string assembly. The term “actuate” or “arming” or “activate” is used to indicate the connection of a through wire to a fire wire that is connected to a detonator. The term “ground wire” is used to indicate an electrical ground. The term “firing a detonator or perforating gun” is used to indicate an event when an electrical signal is transmitted through a through wire to the fire wire of a detonator.

Preferred Embodiment System Wired Perforating Gun (0500)

(20) The present invention may be seen in more detail as generally illustrated in FIG. 5 (0500), wherein a perforating gun (0500) is pre-wired with a cable (0501) through pre finished holes (0503) drilled into the body of the perforating gun (0500). According to a preferred exemplary embodiment, the holes are machined in the perforating gun (0500) at pre-determined points that are best suited to allow the cable to pass through without causing stress on the perforating gun. The holes may be machined in a helical manner. The holes may be circular, elliptical, or square shaped. According to a preferred exemplary embodiment, the cable may be held by clips (0502) or other fastening means. According to a preferred exemplary embodiment, the cable may pass through clips or other routing means. According to another preferred exemplary embodiment, the cable comprises at least two conducting wires. The cable may be routed on the inside of the charge holder tube or on the outside of the charge holder tube. A cross section and a front view of the fastening means (0511) is detailed in FIG. 5a (0510). According to a preferred exemplary embodiment, the cable comprises multiple conductors with a single pin (0504). According to yet another preferred exemplary embodiment, the cable may comprise a through conducting wire and a ground conducting wire. According to a most preferred exemplary embodiment, the cable comprises a through conducting wire, a ground conducting wire, and a firing wire. According to a further preferred exemplary embodiment, the cable comprises a through conducting wire, a ground conducting wire, a communication wire, and a firing wire. According to a most preferred exemplary embodiment, the cable may comprise a through conducting wire. The cable may be part of the wireline that is used to pump down a gun string assembly. The through line is a conductor in the cable that is capable of handling high voltages transmitted from the surface of the oil rig. The through wire may be used to send a voltage signal to an armed detonator to initiate detonation in a detonation train in a perforating gun. The firing wire may be a conductor that may be used to connect to a detonator input from a switch output. The ground line may be part of the wireline for providing a reliable ground to electronic or pressure switches. According to a preferred exemplary embodiment, the communication wire may be part of the wireline and may be used to electronically transmit status information to the surface. For example, a perforating gun's faulty connection may be transmitted via the communication wire to the surface or an operator. According to another preferred exemplary embodiment, the communication wire may be part of the wireline and may be used to electronically receive instructions from the surface. For example, a perforating gun in the gun string assembly may be skipped or disabled by transmitting an instruction from the surface of the oil rig via the communication wire. In another example, an instruction may be transmitted via the communication wire to introduce a delay into the switch for initiating a perforating event at a set time delay. According to a yet another preferred exemplary embodiment, pre-wiring a perforating gun with plural conducting wires eliminates the need to manually cut, crimp, pack, or inspect wires in the field of operations. FIG. 6 (0600) illustrates a perspective view of a wired perforating gun.

Preferred Embodiment System Integrated Perforating Gun Switch Sub Assembly (0700)

(21) The present invention may be seen in more detail as generally illustrated in FIG. 7 (0700), wherein a front section view of a pre-wired perforating gun (0701) with electrical contacts (0727, 0728, 0729) integrated to a switch sub (0702) with electrical contacts (0707, 0708, 0709) is shown. A perspective view is illustrated in FIG. 8 (0800). It should be noted that the term “downstream” (0720) is used to indicate a position that is closer to the toe end of the wellbore casing, and the term “upstream” (0730) is used to indicate a position that is closer to the heel end of the wellbore casing. The switch is part of the switch sub. The switch sub (0702) may comprise an upstream adapter (0750) at an upstream end and a downstream adapter (0740) at a downstream end. The size of the upstream adapter (0750) may be different than the downstream adapter as it enables the switch sub (0702) to be assembled in one direction only. A cable (0714) passing through a charge holder tube in the perforating gun (0701) comprises plural conducting wires. As illustrated in the figure, the cable may comprise a through wire (0738) connected to an electrical contact (0728), a fire/power wire (0737) connected to an electrical contact (0727), and a ground wire (0739) connected to an electrical contact (0729). According to a preferred exemplary embodiment, the electrical contacts (0727, 0728, 0729) may be electrical contact rings. The cable (0714) in the perforating gun (0701) may further be electrically connected at a connection point at a manufacturing facility. The cable may be routed through clips in a charge holder tube to prevent slack and twisting as illustrated in FIG. 5 (0500).

(22) The switch sub (0702) may comprise an adapter configured with electrical contacts. The electrical contacts may be a through wire contact (0708), a ground contact (0709) and a fire/power contact (0707). The adapter may be a hollow member that can accept a switch (0703) that is connected to a detonator (0704) through a retaining member (0731). According to a preferred exemplary embodiment, the switch may be a pressure switch. Pressure switches are conventionally used in perforating gun systems wherein a pressure acted upon a piston in the switch enables a connection between a through wire and a fire wire which is in turn connected to a detonator. According to a preferred exemplary embodiment, the switch may be an electronic switch. According to another preferred exemplary embodiment, the switch is configured with a pre-determined electronic time delay. For example, the switch may be programmed with a delay such that a firing event in a perforating gun activates a timer in the next switch. The switch may then be actuated when the timer expired. Subsequently, another timer in an upstream switch may be initiated and, upon expiration of the timer, the upstream switch may be armed without the need for actuation forces to actuate the switch. According to a preferred exemplary embodiment, the switch is actuated by the pre-determined time delay or actuation forces, or a combination thereof. The pre-determined electronic time delay may be programmed to 1 minute. The pre-determined electronic time delay may be programmed in the range of 10 seconds to 10 minutes. The output of the switch may be 3 conducting wires, a ground wire (0719), a through wire (0718), and a power wire (0717). According to yet another preferred exemplary embodiment, the switch is configured with a pre-determined ballistic time delay. For example, the switch may be programmed with a ballistic delay such that a firing event in a perforating gun with a detonator activates a timer in a switch attached to the detonator without the need for actuation forces from a perforation gun or wellbore pressure. The ballistic time delay is the time required to burn the length of a ballistic wire connected to the detonator. The length of the ballistic wire may be customized to achieve the desired time for the ballistic time delay. For example, a length of 10 inches might provide a ballistic time delay of 1 minute. Plural detonating members may be strung together to achieve the desired ballistic time delay. For example, one detonating member may result in a 6 minute delay, 2 detonating members in series may produce a 12 minute delay, and so on. The output of the switch may be connected to the other end of the switch sub to electrical contacts in an adapter. The connections between the adapters at both ends of the switch may be solid conducting rods or conducting wires.

(23) According to a preferred exemplary embodiment, the pre wired switch sub (0702) is screwed/attached into the pre wired perforating gun (0701) so that the electrical contacts in the perforating gun are connected to electrical contacts in the switch sub respectively. The electrical contacts may be machined in the end plate (0710) of the perforating gun. When the perforating gun (0701) is fired the detonator receives a signal from the surface, which then initiates a detonating or ballistic event. The ballistic event is transferred via an aligned bidi transfer (0705) to a detonating cord (0706). Plural shaped charges that are attached to the detonating cord carry out the perforation into a hydrocarbon formation.

(24) According to a further exemplary embodiment, when the perforating gun (0701) is fired, the switch (0703) is activated, which then arms the detonator upstream of the switch sub (0703) by connecting the through wire (0718) to the fire/power line of the detonator upstream.

Preferred Embodiment System Electrical Diagram (0900)

(25) The present invention may be seen in more detail as generally illustrated in FIG. 9 (0900), wherein an electrical connection diagram between a perforating gun, a detonator and a switch sub is shown. The perforating gun (0940) is connected to a switch sub (0920) at the gun's downstream end and to a switch sub (0930) at the gun's upstream end. It should be noted that the term “downstream” is used to indicate a position that is closer to the toe end of the wellbore casing, and the term “upstream” is used to indicate a position that is closer to the heel end of the wellbore casing. The term “fire wire” or “arming wire” is used to indicate an input that is electrically connected to a detonator. The term “through wire” is used to indicate a conducting electrical wire that is part of a wireline cable that is connected to a gun string assembly. The term “actuate” or “arming” is used to indicate the connection of a through wire to a fire wire that is connected to a detonator. The term “ground wire” is used to indicate an electrical ground. The term “firing a detonator or perforating gun” is used to indicate an event when an electrical signal is transmitted through a through wire to the fire wire of a detonator.

(26) The switch is positioned in a switch sub. The electrical connection includes a switch (0902) electrically connected to a detonator (0903) that is positioned upstream of the switch (0902) and downstream of the switch (0901). The power/fire output (0907) of switch (0902) is connected to the input of the upstream detonator (0903). The ground output (0916) of switch (0902) is connected to the other input of the upstream detonator (0903) and also to the upstream switch (0901) through a cable in a perforating gun. The through wire output (0915) of the downstream switch (0902) is connected to the input of the upstream switch (0901) through a cable in a perforating gun. The inputs to the downstream switch (0902) are through wire (0905) and ground wire (0906), which are outputs from a switch downstream of switch (0902). The outputs of upstream switch (0901), through wire (0925), and ground wire (0926) are connected to the inputs of a switch positioned upstream of switch (0901). Similarly, fire wire (0927) is further connected to a detonator positioned upstream of switch (0901). When a perforating gun fires downstream of switch (0902), it enables switch (0902) i.e., connects the through wire (0905) to the fire wire (0907) whereby detonator (0903) is enabled. Similarly, when detonator (0903) is fired, it enables upstream switch (0901) by connecting the through wire (0925) to the fire/power wire (0927) that is connected to the input of an upstream detonator.

Preferred Exemplary Wellbore Perforating Gun Assembly Flowchart Embodiment (1000)

(27) As generally seen in the flow chart of FIG. 10 (1000), a preferred exemplary wellbore perforation gun assembly method may be generally described in terms of the following steps: (1) pre-wiring perforating guns with a single cable comprising multiple conductors (1001); As shown above in FIG. 5 (0500), a perforating gun may be prewired with a cable through the holes and clips in the perforating gun in a manufacturing facility. (2) attaching a prewired switch sub to a prewired perforating gun in a gun string assembly (1002). The perforating gun comprises secondary explosives (shaped charges) while the switch sub comprises primary detonation (detonator). According to a preferred exemplary embodiment, attaching a perforating gun comprising secondary explosives with a switch sub comprising primary explosives eliminates the need for manual connections in the field of operations. (3) repeating steps (1001) and (1002) until all perforating guns are attached to switch subs (1003). As shown above in FIG. 7 (0700), a switch sub may be screwed or attached to perforating guns at the upstream and downstream ends of the switch sub.

Preferred Exemplary Wellbore Perforating Gun Flowchart Embodiment (1100)

(28) As generally seen in the flow chart of FIG. 11 (1100), a preferred exemplary wellbore gun perforating method may be generally described in terms of the following steps: (1) attaching the wired switch sub to the first wired perforating gun in a gun string assembly (1101); (2) repeating the step (1101) until desired number of plural wired perforating guns are attached to plural wired switch subs in the gun string assembly (1102); (3) deploying the gun string assembly into the wellbore casing with a wireline comprising the first cable (1103); (4) isolating a perforating stage in the wellbore casing (1104); (5) firing the first wired perforating gun that is positioned at a downstream end of the wellbore casing with a trigger signal in one of the plurality of first conducting wires in the first cable (1105); For example, a downstream gun attached to switch (0902) may be fired as shown in FIG. 9 (0900). According to a preferred embodiment, the switch may be activated in step (1106) by an output of a detonator that is used to fire the downstream gun. When a detonator is fired, the blast travels away from the switch in the downstream direction of the perforating gun. This is in contrast to prior art switch activations, wherein pressure switches are primarily activated by the actuation force of the main explosive train (shaped charges) or wellbore pressure. According to a preferred exemplary embodiment, the pressure switch is activated by the blast created by primary explosives (detonator). This method of activating the pressure switch is reliable, repeatable, and reproducible as compared to unreliable switch activation methods taught in current prior art. (6) activating a switch in the wired switch sub and electrically disconnecting the first wired perforating gun (1106); The wired switch sub is connected to the first wired perforating gun at a downstream end of the switch sub and a second wired perforating gun that is connected to the upstream end of the switch sub; As illustrated in FIG. 9 (0900), the switch (0902) is activated when a downstream gun (GUN1) attached downstream to switch (0902) is fired. As described above in step (1105), the switch may be activated by the output of a detonator. GUN1 is electrically disconnected from the through wire after it is fired. The switch (0902) may be connected to GUN1 at a downstream end of the switch sub and to an upstream perforating gun (GUN2) at an upstream end of the switch sub. The GUN2 may be attached to another switch (0901) on its upstream end. Likewise, when GUN2 is fired, it activates switch (0901) and disconnects GUN2 electrically from the through wire. The process may continue until all the perforating guns in the gun string assembly are fired. (7) pulling the gun string assembly upstream with the switch activated and firing a second wired perforating gun with a detonator positioned upstream of the second wired perforating gun (1107); As shown in FIG. 9 (0900), when GUN2 is fired with the detonator (0903) that is positioned upstream of GUN2, it activates switch (0901) and disconnects GUN2 electrically from the through wire. The process may continue until all the perforating guns in the gun string assembly are fired. (8) Checking whether all perforation stages have been completed, if not, proceeding to the step (1105) (1108); and (9) Pulling the gun string assembly out of the wellbore casing and preparing for the next isolated stage (1109).

Preferred Exemplary Wellbore Perforating Gun Sequence Flowchart Embodiment (1200)

(29) As generally seen in the flow chart of FIG. 12 (1200), a preferred exemplary wellbore gun perforating sequence method may be generally described in terms of the following steps: (1) Arming and firing a first downstream perforating gun (1201); (2) Enabling a first switch that connects a through wire to a firing wire of a first detonator that is positioned between a second upstream perforating gun and a second upstream switch (1202); (3) Sending a signal and firing the second upstream perforating gun (1203); (4) Enabling a second switch that connects a through wire to a firing wire of a second detonator that is positioned between a third upstream perforating gun and a third upstream switch (1204); (5) Repeating steps (1202) to (1204) until all stages are completed in the fracturing zone (1205).

Preferred Embodiment System Switch Sub Embodiment (1300)

(30) The present invention may be seen in more detail as generally illustrated in FIG. 13 (1300), wherein a switch sub (1300) comprises an upstream adapter (1331) and a downstream adapter (1321). It should be noted that the term “downstream sub end” (1320) is used to indicate a position that is in the direction towards the toe end of the wellbore casing, and the term “upstream sub end” (1330) is used to indicate a position that is in the direction closer towards the heel end of the wellbore casing. The switch sub (1300) may be attached to an upstream end of perforating gun with the downstream adapter (1321). Similarly, the switch sub may be attached to a downstream end of perforating gun with the upstream adapter (1331). The upstream adapter (1331) may be a different size than the downstream adapter (1321) for preventing undesired or improper electrical connections. The sizes of the upstream adapter (1331) and the downstream adapter are chosen such that the switch sub may not be flipped/reversed, which may result in incorrect/improper electrical connections and assembly of the gun string. According to a preferred exemplary embodiment, the sizes of the upstream adapter and downstream adapters are different for safety purposes. The downstream adapter (1321) may have a primary explosive or a detonator connected, while the upstream adapter (1331) may not have a detonator connected. The downstream adapter (1321) may comprise plural electrical contacts, which include a through wire contact (1303), a ground wire contact (1305), and a power wire contact (1304). Similarly, the upstream adapter (1331) may comprise plural electrical contacts, which include a through wire contact (1313), a ground wire contact (1315), and a power wire contact (1314). The downstream adapter in the switch sub (1300) may be configured to accept a switch that is connected to detonator (1302) as described above in FIG. 7 (0700). According to a preferred exemplary embodiment, the upstream adapter is attached to a downstream end of a perforating gun providing electrical connection through the electrical contacts of the adapter and the electrical contacts of the perforating gun. According to another preferred exemplary embodiment, the downstream adapter is attached to an upstream end of a perforating gun providing electrical connection through the electrical contacts of the downstream adapter and the electrical contacts of the perforating gun. The upstream adapter (1331), and the downstream adapter (1321) may be electrically connected with conducting rods (1301) or through wires. According to a preferred exemplary embodiment, the upstream adapter (1331), the detonator and the downstream adapter (1321) may be electrically connected into a single cartridge. According to yet another preferred exemplary embodiment, the cartridge may be loaded through a single end into the switch sub. According to yet another preferred exemplary embodiment, the cartridge may be tested independently with a perforating gun. According to yet another preferred exemplary embodiment, the switch sub survives a perforating event and remains. The switch sub (1300) may contain ports for testing purposes.

System Summary

(31) The present invention system anticipates a wide variety of variations in the basic theme of perforating, but can be generalized as a wellbore perforating system for use in a wellbore casing comprising: (a) a first wired perforating gun; and (b) a wired switch sub; wherein the first wired perforating gun comprises a first charge holder tube; the first charge holder tube is wired with a first cable comprising a first plurality of conducting wires; the first plurality of conducting wires are in operative electrical connection to a first plurality of electrical contacts; the first plurality of electrical contacts are located at a first upstream gun end in an end plate of the first wired perforating gun; the wired switch sub comprises a downstream sub end; the downstream sub end having a downstream adapter; and the downstream adapter is configured to be screwed to the first upstream gun end; the downstream adapter is configured with a plurality of downstream sub electrical contacts; the plurality of downstream sub electrical contacts are each configured for operative connection to the first plurality of electrical contacts.

(32) This general system summary may be augmented by the various elements described herein to produce a wide variety of invention embodiments consistent with this overall design description.

Method Summary

(33) The present invention method anticipates a wide variety of variations in the basic theme of implementation, but can be generalized as a wellbore perforating method wherein the method is performed on a wellbore perforating system comprising: (a) a first wired perforating gun; and (b) a wired switch sub; wherein the first wired perforating gun comprises a first charge holder tube; the first charge holder tube is wired with a first cable comprising a first plurality of conducting wires; the first plurality of conducting wires are in operative electrical connection to a first plurality of electrical contacts; the first plurality of electrical contacts are located at a first upstream gun end in an end plate of the first wired perforating gun; the wired switch sub comprises a downstream sub end; the downstream sub end having a downstream adapter; and the downstream adapter is configured to be screwed to the first upstream gun end; the downstream adapter is configured with a plurality of downstream sub electrical contacts; the plurality of downstream sub electrical contacts are each configured for operative connection to the first plurality of electrical contacts; wherein the method comprises the steps of: (1) attaching the wired switch sub to the first wired perforating gun in a gun string assembly; (2) repeating the step (1) until desired number of wired perforating guns are attached to wired switch subs in the gun string assembly; (3) deploying the gun string assembly into the wellbore casing with a wireline comprising the first cable; (4) isolating a perforating stage in the wellbore casing; (5) firing the first wired perforating gun that is positioned at a downstream end of the wellbore casing with a trigger signal in one of the pluralities of first conducting wires in the first cable; (6) activating a switch in the wired switch sub and electrically disconnecting the first wired perforating gun; (7) pulling the gun string assembly upstream with the switch activated and firing the second wired perforating gun with a detonator positioned upstream of the second wired perforating gun; (8) checking whether all perforation stages have been completed, if not, proceeding to the step (5); and (9) pulling the gun string assembly out of the wellbore casing and preparing for the next isolated stage.

(34) This general method summary may be augmented by the various elements described herein to produce a wide variety of invention embodiments consistent with this overall design description.

System/Method Variations

(35) The present invention anticipates a wide variety of variations in the basic theme of oil and gas perforations. The examples presented previously do not represent the entire scope of possible usages. They are meant to cite a few of the almost limitless possibilities.

(36) This basic system and method may be augmented with a variety of ancillary embodiments, including but not limited to an embodiment further comprises a second wired perforating gun, wherein: the second wired perforating gun comprises a second charge holder tube; the second charge holder tube is wired with a second cable comprising a second plurality of conducting wires; the second plurality of conducting wires are in operative electrical connection to a second plurality of electrical contacts; the second plurality of electrical contacts are located at a second downstream gun end in an end plate of the second wired perforating gun; wherein the wired switch sub further comprises a upstream sub end; the upstream sub end having an upstream adapter; and wherein the upstream adapter is configured to be screwed to the second downstream gun end; the upstream adapter is configured with a plurality of upstream sub electrical contacts; the plurality of upstream sub electrical contacts are each configured for operative connection to one of a plurality of the second electrical contacts in the second downstream gun end.

(37) In another embodiment, the downstream adapter is configured to accept a detonator; wherein the detonator is configured to be connected to a switch; and whereby when perforating, and the detonator is received in the downstream adapter, the detonator transfers a ballistic event to a detonating cord in a the first wired perforating gun.

(38) In another embodiment, the switch is configured to an operative electrical connection to the upstream adapter.

(39) In another embodiment, the switch is a pressure activated switch.

(40) In another embodiment, the switch is an electronic switch.

(41) In another embodiment, the upstream adapter and the downstream adapter are configured to connect to each other to form a cartridge.

(42) In another embodiment, the cartridge is loaded from one end of the wired switch sub.

(43) In another embodiment, said switch is configured with a pre-determined electronic time delay.

(44) In another embodiment, the switch is configured with a pre-determined ballistic time delay.

(45) In another embodiment, the activating of a switch is initiated by an output of a detonator.

Wired Perforating Gun System Summary

(46) The present invention system anticipates a wide variety of variations in the basic theme of perforating, but can be generalized as wellbore perforating gun system for use in a wellbore casing comprising a wired perforating gun; the wired perforating gun comprises a charge holder tube; the charge holder tube is wired with a cable comprising a plurality of conducting wires; the plurality of conducting wires are configured for operative electrical connections to a switch sub.

Wired Perforating Gun System/Method Variations

(47) The present invention anticipates a wide variety of variations in the basic theme of oil and gas perforations. The examples presented previously do not represent the entire scope of possible usages. They are meant to cite a few of the almost limitless possibilities.

(48) This basic system and method may be augmented with a variety of ancillary embodiments, including but not limited to an embodiment wherein the charge holder tube comprises a plurality of holes; the plurality of holes are configured to allow the cable to pass through.

(49) This system and method may be augmented with a an embodiment wherein the plurality of conducting wires are each configured for operative electrical connection to one of a plurality of electrical contacts; the plurality of electrical contacts are positioned in an end plate in the charge holder tube.

(50) This system and method may be augmented with an embodiment wherein the cable is held by fastening means.

(51) This system and method may be augmented with an embodiment wherein the cable is routed with clips attached to the charge holder tube.

(52) This system and method may be augmented with an embodiment wherein the holes are machined at pre-determined points in the charge holder tube.

(53) This system and method may be augmented with an embodiment wherein the cable further comprises three conducting wires.

(54) This system and method may be augmented with an embodiment wherein the cable further comprises a ground wire, a through wire and a fire wire.

(55) This system and method may be augmented with an embodiment wherein the cable further comprises a ground wire, a through wire, a fire wire and a communication wire.

(56) This system and method may be augmented with an embodiment wherein the communication wire is configured to receive instructions electronically.

(57) This system and method may be augmented with an embodiment wherein the communication wire is configured to transmit status electronically.

(58) This system and method may be augmented with an embodiment wherein the cable is held by clips in the charge holder tube.

(59) One skilled in the art will recognize that other embodiments are possible based on combinations of elements taught within the above invention description, but that at least one embodiment is directed to a wellbore perforating system and method with reliable and safer connections in a perforating gun assembly. 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.