Patent Application
20250020046
Not applicable.
In a project for drilling a hydrocarbon-producing well and bringing the well online and into production, the process of perforating the wellbore and fracking those perforations is a multi-day effort requiring a lot of equipment and personnel. As such, an efficient but effective perfing and fracking operation is a considerable concern for the investors and operators of such new wells. The total number of perforations needed to be created and fracked is an important and financially weighty decision recognizing that too few perforations may limit the productivity of the well while too many perforations adds significant costs. In long horizontal wells, it is impractical to puncture all of the perforations in one quick process and then frack all of the perforations in a single following step. Perfing and fracking is done in bite size segments limited mostly by the number of guns that will fit in a single toolstring. Toolstrings are generally limited by the length of the wireline lubricator brought to the site and that tends to be between 40 and 60 feet.
The casing is perforated very far down hole such that getting a toolstring from the surface to the operative position within the casing commonly takes a couple of hours. A round trip is typically at least three hours and, if all goes smoothly, takes up to about five or six hours. Considering the costs at the wellsite on a per hour basis, it is very important that the guns fire when signaled. Unfortunately, while most current gun designs provide better than 99% reliability, anything less than 100% is disappointing and expensive.
Failures to detonate seem to most commonly occur in the electric system. The same electric system through the wireline serves as both the electronic signaling and the electric power to drive the detonator to detonate, so it needs to be designed to avoid multiple types of failure. On the electronic side, the communications must be perfectly continuous. Any momentary loss of continuous electric signal causes a reset on digital switches and requires a reprogramming process where all of the switches are provided their individual mission protocol. The overall mission protocol is for each switch to individually open an electric path to its individual and respective detonator to activate in sequence from bottom to top and as signaled. When a reset occurs, the switches need to be reprogrammed to know where each is in the firing order so that only the designated detonator is detonated and that designated detonator is actually detonated when signaled. Essentially, a brief loss of signal continuity causes the switches to forget where they are in the order. As long as the brief loss of continuity is not associated with a larger problem and is discovered at a time when the guns are not intended to be fired such as near the top of the hole when being pumped down, reprogramming is not a significant cause for concern. But it is certainly disconcerting and preferably avoided. Such brief discontinuities can be caused or associated with the banging of the toolstring progressing down hole at casing joints or the impulse forces when the plug is set or other guns are fired where a spring connector is compressed and slackened quickly and briefly lifts off its terminal. Wire connections tend to be slightly more fragile at their junctions then is desirable.
Turning to failures for the electric conduction system, there is a risk of failing when higher voltage power is delivered for detonation of a gun if any kind of conductive dust or debris gets loosened after the guns string is assembled at the surface. This debris seems to work its way into gaps between the positive and negative sides of the circuit when the two sides are in some proximity to one another. With conductive dust not necessarily connecting the two sides, but reducing the effective spacing between the positive and negative, a shortened arc path is created for an electric short to occur. This short deprives the detonator of the power needed to detonate.
Again, the root cause seems to be shots from other guns, blasts from plug setting tools and the rattling, bumping, vibration endured while being conducted miles down the casing. And, it is unlikely that harsh impulses and G-forces can be much mitigated. What is apparently needed are more robust electric systems that improve reliability of guns in a perforating string.
An embodiment of a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprises a tandem sub comprising a sub housing and a signal pod receivable in the sub housing, wherein the signal pod comprises a detonator and a receptacle; and a perforating gun comprising a charge carrier configured to receive one or more shaped charges, the charge carrier comprising a detonator cord housing configured to receive a terminal end of a detonator cord, and wherein the detonator cord housing is receivable in the receptacle of the signal pod to ballistically couple the detonator cord with the detonator. In some embodiments, having a longitudinal axis extending lengthwise along the cross sectional centers of the tandem sub and the perforating gun where the longitudinal axis is generally linear but may curve when the perforating gun system is subjected to bending force such as within a tortuous borehole, and further wherein the terminal end of the detonator cord, the detonator cord housing, and the receptacle are each aligned with their cross sectional center along longitudinal axis and extending coaxially therewith. In some embodiments, the detonator cord housing is tubular defining an internal passage in which the terminal end of the detonator cord is receivable. In some embodiments, the receptacle permits relative rotation between the receptacle and the detonator cord housing when the detonator cord housing is received in the receptacle. In some embodiments, the perforating gun comprises a cord endcap connectable to the terminal end of the detonator cord when the terminal end is received in the detonator cord housing whereby interference between an outer diameter of the cord endcap and an inner diameter of the detonator cord housing, the outer diameter being equal to or greater than the inner diameter, restricts the terminal end of the detonator cord from releasing from the detonator cord housing. In some embodiments, a ratio of an inner diameter to a wall thickness of the detonator cord housing is between 4:1 and 25:1.
An embodiment of a perforating gun deployable in a wellbore extending through a subterranean earthen formation comprises an outer gun housing extending between opposing longitudinal ends and defining an internal passage extending between the longitudinal ends of the gun housing; a charge carrier receivable in the internal passage of the gun housing, the charge carrier comprising a carrier chassis configured to at least partially receive one or more shaped charges, and a detonator cord housing configured to receive a terminal end of a detonator cord, and wherein the detonator cord housing is coupled to the carrier chassis and at least partially projects externally from the carrier chassis of the charge carrier. In some embodiments, the perforating gun comprises an assembled state in which the charge carrier is received in the internal passage of the gun housing such that the detonator cord housing does not project beyond either of the longitudinal ends of the gun housing. In some embodiments, a longitudinal length of the gun housing is greater than a longitudinal length of the charge carrier including the detonator cord housing at least partially projecting from the carrier chassis of the charge carrier. In some embodiments, the carrier chassis extends between a pair of opposing longitudinal ends and wherein the detonator cord housing projects outwardly from one of the longitudinal ends of the carrier chassis. In some embodiments, the detonator cord housing projects longitudinally from one of the longitudinal ends of the carrier chassis to define a longitudinal end of the charge carrier. In some embodiments, the detonator cord housing is pivotably coupled to the carrier chassis. In some embodiments, the detonator cord housing is permitted to rotate relative to the carrier chassis. In some embodiments, the detonator cord housing is flexibly coupled to the carrier chassis to pivot and to displace radially relative to the longitudinal axis.
An embodiment of a tandem sub deployable in a wellbore extending through a subterranean earthen formation comprises an outer sub housing defining an internal passage; a signal pod receivable in the internal passage of the sub housing, the signal pod comprising a pod chassis configured to receive a detonator, and receive an electroballistic connector into the pod chassis so as to electrically connect the signal pod with a corresponding perforating gun and to also place the detonator cord into ballistic communication with the detonator when electroballistic connector is received into the pod chassis.
An embodiment of a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprises a tandem sub comprising a sub housing and a signal pod receivable in the sub housing, wherein the signal pod comprises a chassis defining an internal ballistic cavity wherein the internal ballistic cavity includes a detonator receptacle and a detonator cord receptacle, where the detonator receptacle is arranged to receive a detonator in a predefined detonator position, and the detonator cord receptacle is arranged to receive a terminal end of a detonator cord and position the terminal end in a predefined cord position within the chassis in ballistic communication with the detonator; a perforating gun comprising a charge carrier configured to receive one or more shaped charges, the charge carrier comprising a detonator cord housing configured to receive the terminal end of the detonator cord where the detonator cord housing adds rigidity to the terminal end of the detonator cord for insertion into the detonator cord receptacle. In some embodiments, the detonator cord comprises a disassembled state in which the terminal end of the detonator cord is not received in the detonator cord housing and in which the terminal end of the detonator cord has a first mechanical strength; and the detonator cord comprises an assembled state in which the terminal end of the detonator cord is received in the detonator cord housing to provide the terminal end of the detonator cord with a second mechanical strength that is greater than the first mechanical strength. In some embodiments, the first mechanical strength of the detonator cord is less than a mechanical strength of the detonator cord housing. In some embodiments, the detonator cord housing comprises one or more ports spaced along the detonator cord housing to increase a flow area of the detonator cord housing for the passage of ballistic energy from the detonator upon detonation.
An embodiment of a method for deploying a plurality of perforating gun systems from a remote location into a wellbore located at a wellsite comprises (a) transporting each of the plurality of perforating gun system from the remote location to the wellsite in a transport state in which one or more shaped charges of the perforating gun system are ballistically coupled to a detonator cord of the perforating gun system but ballistically decoupled from a detonator of each of the plurality of perforating gun systems; and (b) transitioning, after the plurality of perforating gun systems arrives at the wellsite, a first perforating gun system of the plurality of perforating gun systems from the transport state to a deployment state for deployment into the wellbore by ballistically coupling the detonator cord of the first perforating gun system with the detonator of a second perforating gun system of the plurality of perforating gun systems. In some embodiments, (b) comprises transitioning the first perforating gun system from the transport state to the deployment state in response to mechanically rotatably coupling the first perforating gun system with the second perforating gun system. In some embodiments, (b) comprises transitioning the first perforating gun system from the transport state to the deployment state automatically in response to inserting the detonator cord housing into a corresponding receptacle of the second perforating gun system.
An embodiment of a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprises one or more shaped charges; a detonator cord ballistically coupled to the one or more shaped charges when the perforating gun system in both a transport state and a deployment state; and a detonator ballistically coupled to the detonator cord when the perforating gun system is in the deployment state but ballistically decoupled when the perforating gun system is in the transport state; wherein the perforating gun system is transitionable at a wellsite from the transport state to the deployment state.
An embodiment of a signal pod for a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprise a chassis having a longitudinal axis; a printed circuit board attached to the chassis; a receptacle at a longitudinal first end of the chassis; a first electrical connector positioned within the receptacle and electrically connected to the printed circuit board; a second electrical connector positioned at a longitudinal second end of the signal pod opposite the first end and wherein the second electrical connector is electrically connected to the printed circuit board; a ground electrical contact extending from the printed circuit board and electrically connected thereto; and a detonator electrically connected to the printed circuit board and positioned between a longitudinal midline of the chassis and the first end of the chassis. In some embodiments, the chassis defines an external opening and the signal pod further comprises a cover connectable to the chassis to enclose the external opening while permitting fluid communication across an interface formed between the cover and the external opening. In some embodiments, the first electrical connector comprises an electrical spring contact oriented to flex radially into and away from a longitudinal axis of the receptacle. In some embodiments, the second electrical connector comprises an electrical spring contact oriented to flex radially into and away from the through axis in a generally radial direction relative to the through axis. In some embodiments, the ground electrical connector includes a spring contact oriented to flex into and away from the longitudinal axis of the chassis. In some embodiments, the receptacle has a receptacle axis and the signal in electrical connector includes a spring contact oriented to flex into and away from the receptacle axis in a generally radial direction relative to the receptacle axis and the through electrical connector has a through axis and the through electrical connector includes a spring contact oriented to flex into and away from the through axis in a generally radial direction relative to the through axis and the ground electrical connector includes a spring contact oriented to flex into and away from the longitudinal axis of the chassis. In some embodiments, the receptacle axis and the through axis are generally aligned with the longitudinal axis of the chassis. Where the detonator is arranged parallel to the axis of the chassis. Where the signal pod includes a reflector over the detonator to reflect explosive energy back toward the longitudinal axis. Where the detonator has a top end and a bottom end such that explosive energy from the detonator is higher at the bottom end as compared to the top end and the detonator is arranged at an angle to the axis such that the bottom end is turned toward the longitudinal axis. Where the angle is less than 45, 30, 25, 20, 15 degrees and more than 2, 3, 4, 5 degrees. Where the signal pod includes a reflector over the angled detonator to reflect explosive energy back toward the longitudinal axis of the chassis. In some embodiments, each of the first electrical connector, second electrical connector, and the ground electrical contact comprise electrical spring contacts oriented to flex transverse to a longitudinal axis of the signal pod.
An embodiment of a tandem sub system for perforating guns comprises a tandem sub including a signal pod cavity, a throughbore and a cavity for a pressure bulkhead; a signal pod comprising a chassis having a longitudinal axis; a printed circuit board attached to the chassis; a receptacle at a longitudinal first end of the chassis; a first electrical connector positioned within the receptacle and electrically connected to the printed circuit board; a second electrical connector positioned at a longitudinal second end of the signal pod opposite the first end and wherein the second electrical connector is electrically connected to the printed circuit board; a ground electrical contact extending from the printed circuit board and electrically connected thereto; and a detonator electrically connected to the printed circuit board and positioned between a longitudinal midline of the chassis and the first end of the chassis; and a pressure bulkhead connected to the second electrical connector where the pressure bulkhead includes conductive core and an insulating body where the conductive core is connectable to a next tool in the system. In some embodiments, the second electrical connector is arranged to connect to the pressure bulkhead such that at least one of the second electrical connector and the pressure bulkhead includes a spring contact portion that move into and away from the longitudinal axis as engagement of the second electrical connector is made with the pressure bulkhead. In some embodiments, the second electrical connector engages with the pressure bulkhead within the throughbore between the signal pod cavity and the cavity for the bulkhead. In some embodiments, the pressure bulkhead includes a conductive axial post for connecting to a further perforating gun wherein the contact portion of the axial post is on the outer periphery such that engagement with the further perforating gun is radially oriented relative to the longitudinal axis. In some embodiments, the pressure bulkhead includes an insulating skirt spaced from but overlying the conductive axial post to restrict conductive particles inside the gun from gathering near the axial post to reduce the potential of the formation of a short circuit from the axial post to an electrical ground such as the tandem sub. In some embodiments, each of the first electrical connector, second electrical connector, and the ground electrical contact comprise electrical spring contacts oriented to flex transverse to the longitudinal axis of the chassis. In some embodiments, the chassis defines an external opening and the signal pod further comprises a cover connectable to the chassis to enclose the external opening while permitting fluid communication across an interface formed between the cover and the external opening. In some embodiments, the first electrical connector comprises an electrical spring contact oriented to flex radially into and away from a longitudinal axis of the receptacle. In some embodiments, the second electrical connector comprises an electrical spring contact oriented to flex radially into and away from the through axis in a generally radial direction relative to the through axis. In some embodiments, the receptacle has a receptacle axis and the signal in electrical connector includes a spring contact oriented to flex into and away from the receptacle axis in a generally radial direction relative to the receptacle axis and the through electrical connector has a through axis and the through electrical connector includes a spring contact oriented to flex into and away from the through axis in a generally radial direction relative to the through axis and the ground electrical connector includes a spring contact oriented to flex into and away from the longitudinal axis of the chassis. In some embodiments, the receptacle axis and the through axis are generally aligned with the longitudinal axis of the chassis. In some embodiments, the detonator is arranged parallel to the axis of the chassis. In some embodiments, the signal pod includes a reflector over the detonator to reflect explosive energy back toward the longitudinal axis.
An embodiment of a perforating gun system deployable in a wellbore extending through a subterranean earthen formation, the perforating gun system having a longitudinal axis and comprises a first perforating gun comprising a charge carrier configured to receive one or more shaped charges, the charge carrier comprising a detonator cord housing configured to receive a terminal end of a detonator cord and support the detonator cord along the longitudinal axis; a tandem sub comprising a sub housing and a signal pod cavity, a throughbore and a cavity for a pressure bulkhead; a signal pod comprising: a chassis having a longitudinal axis; a printed circuit board attached to the chassis; a receptacle at a longitudinal first end of the chassis; a first electrical connector positioned within the receptacle and electrically connected to the printed circuit board; a second electrical connector positioned at a longitudinal second end of the signal pod opposite the first end and wherein the second electrical connector is electrically connected to the printed circuit board; a ground electrical contact extending from the printed circuit board and electrically connected thereto; and a detonator electrically connected to the printed circuit board and positioned between a longitudinal midline of the chassis and the first end of the chassis; a pressure bulkhead connected to the second electrical connector where the pressure bulkhead includes conductive core and an insulating body where the conductive core with a conductive axial post; and a second perforating gun also configured to receive one or more shaped charges, and including a top plate connector oriented toward the conductive axial post of the pressure bulkhead to enable electric signals received by the signal pod to pass along to the second perforating gun.
An embodiment of a signal pod for a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprises a chassis having a longitudinal axis; a printed circuit board attached to the chassis wherein circuits on the printed circuit board are designed to selectively provide power through two connectors; a receptacle at a longitudinal first end of the chassis; a first electrical connector positioned within the receptacle and electrically connected to the printed circuit board; a second electrical connector positioned at a longitudinal second end of the signal pod opposite the first end and wherein the second electrical connector is electrically connected to the printed circuit board and connectable to an ignitor for a plug setting tool; a ground electrical contact extending from the printed circuit board and electrically connected thereto; and a detonator electrically connected to the printed circuit board and positioned between a longitudinal midline of the chassis and the first end of the chassis; wherein, the circuits on the printed circuit board selectively provides power to the ignitor for a plug setting tool and separately the circuits on the printed circuit board selectively provides power to a detonator for a perforating gun. In some embodiments, a perforating gun system according to claim J1, further including a special tandem sub arranged to connect to a perforating gun at one end and a plug setting tool at the other with a signal pod cavity in which the signal pod is positionable for operation. In some embodiments, the special tandem sub further includes isolation of the signal pod from any flame from ignitor to thereby preserve electrical communication of the signal pod for for later firing of a perforating gun.
An embodiment of a signal pod for a perforating gun system deployable in a wellbore extending through a subterranean earthen formation comprises a chassis having a longitudinal axis; a switch attached to the chassis; a receptacle at a longitudinal first end of the chassis; a first electrical connector positioned within the receptacle and electrically connected to the switch; a second electrical connector positioned at a longitudinal second end of the signal pod opposite the first end and wherein the second electrical connector is electrically connected to the switch; a ground electrical contact extending from the switch and electrically connected thereto; and a detonator electrically connected to the switch; wherein each of the first electrical connector, second electrical connector, and the ground electrical contact comprise electrical spring contacts oriented to flex transverse to the longitudinal axis of the chassis. In some embodiments, the first and second electrical connectors and the ground electrical contact are directly connected to the switch without wire connections.
A more complete understanding of the present invention may be obtained from the following detailed description with reference to the attached drawing figures as summarized below, in which:
The following discussion is directed to various exemplary embodiments of the present disclosure. However, one skilled in the art will understand that the examples disclosed herein have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment. Certain terms are used throughout the following description and claims to refer to particular features or components. As one skilled in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not function. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.
In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices, components, and connections. In addition, as used herein, the terms “axial” and “axially” generally mean along or parallel to a central axis (e.g., central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the central axis. For instance, an axial distance refers to a distance measured along or parallel to the central axis, and a radial distance means a distance measured perpendicular to the central axis. Any reference to up or down in the description and the claims is made for purposes of clarity, with “up”, “upper”, “upwardly”, “uphole”, or “upstream” meaning toward the surface of the borehole and with “down”, “lower”, “downwardly”, “downhole”, or “downstream” meaning toward the terminal end of the borehole, regardless of the borehole orientation. Further, the term “fluid,” as used herein, is intended to encompass both fluids and gasses.
Referring now to
In the configuration shown in
The toolstring 30 includes a number of tools that are selected by an operator of the cased wellbore 10 and which, in this example, includes a plug 31 at the bottom thereof, an adapter kit 32 and a setting tool 33 where the adapter kit 32 is connected between the plug 31 and setting tool 33. Above the setting tool 33 are a number of perforating or “perf” perforating guns 35 along with other tools that include electronic communication with the setting tool 33 and the perforation perforating guns 35 and other tools of toolstring 30 that provide the wellbore location of the toolstring 30 as well as other known functions. A tandem sub 50 may be coupled between the perforating guns 35 to provide pressure isolation therebetween. At the top of the toolstring 30 is a wireline coupling device 36 that attaches to the wireline 28. The wireline 28 extends from the wireline truck, over a pair of sheaves 26 and 27, and is typically quite long to permit the toolstring 30 to run potentially miles down into the cased wellbore 10. It may be generally understood that wellbores, including cased wellbore 10, extend vertically downwards from the surface 7 and then turns along a broad curve to a more horizontal path or portion that is typically a great length (e.g., a mile or more) horizontally through a probable hydrocarbon bearing zone.
Turning to
In
The focus of the present disclosure relates to systems for physically and electrically connecting perforating guns together in a toolstring or gunstring although it may be used in other toolstring connections. Turning to
The perforating guns 35A and 35B are part of a toolstring 30 and each correspond to a different perforating gun system 37A and 37B of the toolstring 30. The term “perforating gun system” as used herein is defined as a system including a charge carrier comprising one or more shaped charges and a detonating cord configured to ballistically couple each of the shaped charges together, and a signal pod comprising a detonator to be ballistically coupled to the detonating cord and an electrical switch for detonating or otherwise activating the detonator to thereby detonate or otherwise activate the shaped charges of the perforating gun system. The charge carrier and signal pod of a given perforating gun system may be packaged in various ways. For example, the charge carrier may be packaged in an outer gun housing as part of a perforating gun while the signal pod may be packaged or received in a sub housing of a separate tandem sub. In other embodiments, the signal pod may instead be directly incorporated with the charge carrier such as, for example, by forming a common perforating gun with the signal pod located internal or external the charge carrier.
Additionally, embodiments of perforating gun systems described herein include a transport state and a separate deployment state where the perforating gun system is transitionable from the transport state to the deployment state. The transport state of the perforating gun system is configured to permit the perforating gun system to be conveniently and safely transported from a remote site to a wellsite containing a wellbore penetrating a subterranean earthen formation. Conversely, the deployment state of the perforating gun system is configured to place the perforating gun system in condition for deployment into the wellbore whereby the one or more shaped charges of the perforating gun system may be detonated by providing the electrical switch of the perforating gun system with an appropriate firing or detonation signal.
In this exemplary embodiment, uphole perforating gun 35A of uphole perforating gun system 37A is shown coupled to a separate tandem sub 50 (e.g., corresponding to an additional perforating gun system separate from systems 37A and 37B) and a tandem sub 50A also corresponding to the first perforating gun system 37A. Additionally, tandem sub 50A is shown coupled to perforating gun 35B which corresponds to a separate perforating gun system 37B comprising a separate tandem sub 50B not shown in
In this exemplary embodiment, the uphole perforating gun 35A is connected at its top end by tandem sub 50 revealing a free pin thread end extending to the left in the uphole direction. A second tandem sub 50A connects the two perforating guns 35A and 35B together by screw threads. In this embodiment, the tandem subs 50 and 50A have double ended pin threads 58 that secure to box threads 38 at the ends of each perforating gun 35.
Turning to
Within the bore of the gun housing 100 is a charge carrier 110 comprising a carrier chassis 120, an uphole endplate 121 coupled to an uphole end of carrier chassis 120, and a downhole endplate 122 on opposite ends thereof and coupled to a downhole end of carrier chassis 120. In this exemplary embodiment, carrier chassis 120 is also a metal tube like the gun housing 100 but with a much thinner wall thickness and will cuts, openings and windows to accommodate various subcomponents as will described or as is currently known. Additionally, charge carrier 120 includes one or more shaped charges 125 and detonator cord 126 ballistically coupled to shaped charges 125. As shown, perforating guns 35A and 35B have three shaped charges 125 and while the detonator cord 126 is only shown at the downhole endplate 122 and extending part way into the carrier chassis 120, it is typically laced around the outside to transfer a ballistic impulse into the base of and detonating the shaped charges 125. Additionally, in this exemplary embodiment, detonator cord 126 is flexible whereby the detonator cord 126 may be elastically deformed as part of “wiring” or otherwise manually ballistically coupling detonator cord 126 with shaped charges 125.
As noted above, the gun housings 100 are connected by screw threads to tandem subs 50 at each end where each tandem sub 50 comprises an outer sub housing 52, a signal pod 150, and a pressure bulkhead 160 both receivable in or otherwise physically supported by the sub housing 52. In this exemplary embodiment, signal pod 150 comprises an electrically conductive pin or passthrough 153 that electrically connects signal pod 150 with pressure bulkhead 160. The signal pod 150 of tandem sub 50 controls the operation (e.g., firing or activation) of a corresponding perforating gun 35A/35B. Particularly, in this exemplary embodiment, signal pod 150 comprises an electrical switch 155 in signal communication with an operator of wireline system 5 at the surface 7 enabling both communication with tools of toolstring 30 located downhole from signal pod 150 and control over the operation of the perforating gun 35A/35B located uphole of signal pod 150. The pressure bulkhead 160 of tandem sub 50 is configured to seal against the sub housing 52 of tandem sub 50 to internally seal the sub housing 52 to thereby seal the pair of perforating guns 35A/35B from the other. As noted above, in this exemplary embodiment, each perforating gun 35A/35B has an air space when fully assembled into the toolstring 30 and this airspace includes the signal pod 150 at the downhole end thereof such that each perforating gun 35A/35B is a bottom fired gun. The signal pod 150, in this exemplary embodiment, particularly includes a detonator 158 adjacent the detonator cord 126 to be in ballistic communication when the “fire” is given by the operator at the surface. Further,
As shown particularly in
In this exemplary embodiment, an annular tool collar 56 is formed or positioned along the outer surface 54 to provide an interface which a tool may be mechanically coupled to apply a rotational torque to the sub housing 52. In this manner, a tool may be coupled to sub housing 52 via tool collar 56 to tighten screw threads into either perforating gun 35A or 35B. Additionally, in this exemplary embodiment, an annular seal assembly 58 is positioned along the outer surface 54 with one of the seal assemblies 58 positioned longitudinally between tool collar 56 and each end 53 and 55 of sub housing 52. Seal assemblies 58 are configured to seal the mechanical connection or interface formed between sub housing 52 and the gun housings 100 of perforating guns 35A and 35B. In this exemplary embodiment, each seal assembly 58 comprises a pair of annular elastomeric seals (e.g., O-ring seals); however, the configuration of seal assemblies 58 may vary in other embodiment.
Sub housing 52 also comprises a central bore or passage defined by an inner surface (e.g., a generally cylindrical inner surface) 60 extending longitudinally between ends 53 and 55. In this exemplary embodiment, the central passage of sub housing 52 defines both a signal pod cavity or receptacle 62 and a pressure bulkhead cavity or receptacle 64 that is separate from the signal pod cavity 62. In this exemplary embodiment, signal pod cavity 62 comprises a relatively large void space at the left end of the sub housing 52 for receiving the signal pod 150. As shown, it may comprise more than 50 percent of the length of the tandem sub but it should be understood that in other embodiments, it may comprise 50 percent of the length or even less. On the right is a pressure bulkhead cavity 64 which is smaller than the signal pod cavity both in terms of length and diameter. Keeping this diameter small is generally preferred to reduce the cross section over which the pressure bulkhead 160 has to carry pressure and an impulse. Between the signal cavity 62 and the pressure bulkhead cavity 64 is an internal passage or throughbore 66 connecting the same. Part of the bulkhead cavity 64 near the downhole end 55 of the sub housing 52 is a set of retainer nut threads 68 for securing a retainer nut 170 (see
Turning back to the signal pod 150 and pressure bulkhead 160 in the sub housing 52, focus should now be turned to the exploded image shown in
Continuing with the description of
One aspect of the design of this exemplary embodiment is limiting access of dust and debris within the air spaces of the perforating guns 35 to work their way into contact with the electronics near the tandem sub 50. Looking at the uphole end of the tandem sub 50, the sub housing 52 of tandem sub 50 is grounded along with the gun housing 100 while the positive side of the electric path comes into the signal pod at downhole contact terminal 136 where a through wire (not shown) may be attached by welding, soldering or other secure system of electrical contact. Downhole contact terminal 136 is located remote from any grounding surface to minimize the possibility of dust (such as from rust) forming an arc path between a grounded element and a positively energized element. In some applications, such proximity is of greater concern at the downhole end of the signal pod 150 where the internal radius of the sub housing 52, in this exemplary embodiment, is smallest at the throughbore 66 and relatively close to the passthrough 153.
In addition, this exemplary embodiment includes a large diameter downhole endplate 122 that extends radially out toward the inside surface of the gun housing 100 and further includes a dust collar 123 (see
In this exemplary embodiment, at the other end of the pressure bulkhead 160 is a series of insulating shrouds creating a tortuous path for any dust or debris to create an arc path from the bulkhead pin connector 164 to the retainer nut 170. Specifically, the positively energized electric circuit passes from passthrough 153 to the female receptacle 163, through the bulkhead conductor 162 to the bulkhead pin connector 164 and then to an electrically conductive uphole electrical connector 131 of the charge carrier 120 of an adjoining perforating gun 35 . . . . Uphole electrical connector 131 of charge carrier 120 comprises a banana socket in this exemplary embodiment including one or more (e.g., circumferentially spaced) electrical contacts 133 that are biased (e.g., mechanically or spring biased) radially inwards into contact with 166 of conductor rod 162. Alternatively, the shape or configuration of uphole electrical connector 131 may vary in other embodiments.
In this exemplary embodiment, uphole electrical connector 131 is secured with a connector nut 124 on the opposite side of the uphole endplate 121 and is connected to a through wire (not shown) by a ring terminal or other known arrangement. A flat ring terminal may be seen pinched between the connector nut 124 and the uphole endplate 121. Back to the subject of the tortuous path, the pressure bulkhead 160 includes a bulkhead shroud 166 that forms an annular space around the bulkhead pin connector 164 in which the banana socket shaped uphole gun connector 131 is inserted. But further, the uphole endplate 121 includes a plate shroud 132 that extends around the bulkhead shroud so that if dust gets past the large diameter uphole endplate 121, it must navigate the tortuous path created by the shrouds. And it must be understood that the effort for resisting any dust intrusion is a time limited effort from the time the toolstring 30 is assembled until the perforating guns 35 are fired which may simply be a matter of hours and one trip down into the wellbore 10, although it is foreseen that guns may be shipped with an uphole tandem sub 50 attached and the potential for such dust could extend back to shipping and transporting such as by forklift and truck. When the tandem subs 50 are attached gun housings 100, the tandem subs 50 are only attached at one end that is at the uphole end of the gun housing 100 such that the detonator 158 is well away from the detonator cord. This is a much safer arrangement for transporting and handling as compared to when the downhole gun contact 135 is inserted into the signal pod putting the detonator 158 in close ballistic communication with the detonator cord 126.
Turning to
Turning now to
Turning now to
The ground contact ports 183 are provided to receive the gun contacts 159 and similarly a passthrough contact port 184 is provided at the downhole end of the pod chassis 151. The switch well 185 is provided with windows to each of these ports so that the switch will be in continuous electrical contact with the electric circuit coming down the uphole perforating gun 35A along with the ground side of the electric circuit and provide a pass-through electrical path on to additional perforating guns 35 or other tools as described above. Specifically, a gun contact window 181A is provided for a spring contact on the bottom of the printed circuit board of the switch 155 to contact downhole gun contact 135. Two ground contact windows 183A are provided for spring contacts on the bottom of the printed circuit board of the switch 155 to contact the ground contacts 159.
With the other contacts installed, the pod cover 152 is attached and secured containing the most vulnerable components of the perforating guns 35 in a neat and tidy package that is easily transported, handled and assembled. The switch cover also helps to retain the det wires and the cover for the detonator wire clips 191 so that the wires do not come loose during shock and firing events.
It should be further noted that any electric connection made through contact is arranged to allow axial movement of the opposite sides of the contact. For example, downhole contact 135 contacts PCB gun contact spring such that disconnecting these two components occurs in a radial direction relative to the axis but easily permits axial movement of the downhole gun contact 135 relative to the switch 155. This is the same for the banana plugs and sockets.
Turning to
While carrier chassis 202 is tubular (e.g., generally cylindrical) in this exemplary embodiment defining interior 203 that extends between the pair of endplates 220 and 250, the shape or configuration of carrier chassis 202, first endplate 220, and/or second endplate 250 may vary in other embodiments. For example, in an alternative embodiment, carrier chassis 202 is not tubular and instead may define one or more discrete receptacles for receiving one or more corresponding shaped charges 125. In this alternative embodiment, endplates 220 and/or 250 may remain as components separate from the carrier chassis 202 or, alternatively, may be incorporated with the carrier chassis 202 whereby, for example, the carrier chassis 202 may form a single integral, or monolithic member with endplates 220 and/or 250.
Endplates 220 and 250 couple to the opposing ends 204 of carrier chassis 202 of charge carrier 200 partially enclosing the interior 203 of carrier chassis 202. In some embodiments, first endplate 220 may comprise an uphole endplate of charge carrier 200 while second endplate 250 may comprise a downhole endplate of charge carrier 200. In other embodiments, first endplate 220 may comprise a downhole endplate of charge carrier 200 while second endplate 250 may comprise an uphole endplate of charge carrier 200. In this exemplary embodiment, first endplate 220 comprises a first or locked member 222, a second or rotatable member 230, and an electroballistic connector 240 that also receives a portion of the detonator cord 126 (e.g., a terminal end thereof) and thus may also be referred to herein as detonator cord housing 240. As used herein, the term “electroballistic connector” refers to a connector configured to concurrently facilitate both an electrical connection with a corresponding electrical connector and a ballistic connection with a corresponding ballistic component (e.g., a component configured to carry or direct a ballistic signal such as a detonator cord, a detonator, an initiator).
As will be discussed further herein, first endplate 220 comprises both a locked member 222 and a rotatable member 230 in order to permit charge carrier 200 to selectably: (i) permit rotation about central axis 205 of charge carrier 200 relative to a surrounding gun housing, and (ii) restrict rotation about central axis 205 of charge carrier 200 relative to the gun housing. Particularly, first endplate 220 additionally includes one or more locking members or elements 225 that may connect (when desired) the locked member 222 with the rotatable member 230 to restrict relative rotation about central axis 205 between members 222 and 230 and thereby restrict relative rotation about central axis 205 between members 222 and 230.
Particularly, the one or more locking elements or members 225 and the first endplate 220 have an unlocked state in which relative rotation about central axis 205 is permitted between members 222 and 230 facilitating relative rotation between charge carrier 200 (with the exception of rotatable member 230) and the surrounding gun housing, and a locked state in which relative rotation about central axis 205 is restricted facilitating the restriction of relative rotation between charge carrier 200 and the surrounding gun housing. The one or more locking elements 225 (or collectively the locking element) of first endplate 220 may be transitioned between the unlocked state and the locked state conveniently at the wellsite during the assembly of the toolstring containing the charge carrier 200 (e.g., a perforating gun such as perforating gun 35A or 35B containing charge carrier 200). In this manner, a single charge carrier 200 may be used with a variety of different types of gun housings, eliminating the need for producing (e.g., eliminating unnecessary tooling, fixtures) and storing (as well as tracking, transporting, etc.) several slightly different versions of the charge carrier 200 for use with these different types of gun housings.
For example, and referring briefly now to
Scalloped gun housing 290 comprises one or more scallops 292 formed in a radially outer surface of housing 290 for similarly reducing the wall thickness of scalloped gun housing 290 whereby second perforating gun 289 may be more conveniently retrieved from the wellbore with fewer complications. However, unlike grooves 282 of the grooved gun housing 280, the scallops 292 of scalloped gun housing 290 do not extend entirely around the central axis of the second perforating gun 289. Instead, scallops 292 extend only partially around the central axis and in
In some applications (e.g., some wellbore completion operations) it may be desirable to employ perforating guns having gun housings that include grooves similar to grooves 282 shown in
Conventionally, charge carriers are typically designed and configured specifically for scalloped gun housings (e.g., gun housings including scallops similar to scallops 292 and not grooves like grooves 282) given that that the charge carrier must be capable of rotationally locking to the gun housing unlike grooved gun housings and thus are typically only used with scalloped gun housings. Similarly, conventionally charge carriers used with grooved gun housings (e.g., gun housings including grooves similar to grooves 282 and not scallops similar to scallops 292) are not used also with scalloped gun housings given they are not equipped for rotationally locking to the scalloped gun housing as needed to maintain angular alignment between the scallops of the gun housing and the shaped charges of the chare carrier.
Unlike conventional charge carriers, charge carrier 200 may be used with grooved gun housings (e.g., grooved gun housing 280) and scalloped gun housings (e.g., scalloped gun housing 290), simplifying (minimizing the number of required steps or equipment, time, cost) the process of producing, storing, tracking, and deploying perforating guns comprising charge carriers 200 (e.g., perforating guns 279 and 289). For instance, instead of needing to deploy a first quantity of “grooved” charge carriers (e.g., charge carriers configured specifically for use with grooved gun housings) to one or more wellsites and a second quantity of “scalloped” charge carriers (e.g., charge carriers configured specifically for use with grooved gun housings) to one or more wellsites, the required quantities of charge carriers 200 may be delivered to the selected well sites and conveniently configured as either “grooved” or “scalloped” charge carriers on-site (or alternatively off-site prior to delivery to the wellsite when desired).
Referring again to
Connectors 226A and 226B have cooperating radially outer peripheral surfaces in engagement with the inner surface of the carrier connector 206 of carrier chassis 202. In this exemplary embodiment, the radially outer surfaces of connectors 226A and 226B are radiused or arcuate in shape to sit substantially flush against the generally cylindrical inner surface of carrier chassis 202. In addition, in certain embodiments, an opposing radially inner surface of each connector 226A and 226B may not be radiused or curved and instead may be flat or planar in shape to minimize the complexity of producing endplate 220 while also maximizing the strength of the connection or joint. For example, the planar inner surface of connectors 226A and 226B presents a planar contact face against which a corresponding annular contact shoulder of the fastener 227 may press against to minimize stress concentrations within connectors 226A/226B and/or fastener 227.
As best seen in
Also shown in
In some embodiments, the minimum ID 235′ of rotatable member 230 is greater than the OD 221 of connector 226, including a maximum OD 221 of connector 226. This permits the rotatable member 230 to be slid axially over the connector 226 of locked member 222 (e.g., without needing to thread rotatable member 230 onto locked member 222) whereby rotatable member 230 axially overlaps locked member 222 about an annular interface formed therebetween along the OD 221 of connector 226 and the ID 235 of rotatable member 230. Axially overlapping locked member 222, the locked member 222 may be coupled to an end 204 of carrier chassis 202 with rotatable member 230 positioned axially between locked member 222 and carrier chassis 202 along the OD 221 of locked member 222. In some embodiments, rotatable member 230 contacts or engages the end 204 of carrier chassis 202 while in other embodiments rotatable member 230 may be slightly more spaced from the carrier chassis 202. In addition, in certain embodiments, the maximum ID 235″ of rotatable member 230 is greater than an OD of carrier chassis 202 permitting the axially inner endface 237 of rotatable member 230 to fit annularly around and axially overlap carrier chassis 202; however, in other embodiments, maximum ID 235″ may be less than the OD of carrier chassis 202 and rotatable member 230 may not fit around or otherwise axially overlap carrier chassis 202.
Locked member 222 connects the first endplate 220 to a selected end 204 of carrier chassis 202 via coupling the member connector 226 of locked member 222 with the carrier connector 206 of carrier chassis 202. Particularly, with member connector 226 coupled to carrier connector 206 of carrier chassis 202, relative rotation between locked member 222 and carrier chassis 202 along with shaped charges 125 when they are installed in carrier chassis 202. In this exemplary embodiment, connectors 206 and 226 comprise mating apertures that each receive a separate corresponding fastener 227 (e.g., a rivet, a threaded fastener as shown in
In this exemplary embodiment, locked member 222 additionally includes an opening or receptacle 228 that at least partially receives the electroballistic connector 240. Electroballistic connector 240 may couple to the first endplate 220 at the receptacle 228 of locked member 222. Additionally, in some embodiments, receptacle 228 facilitates passage of detonator cord 126 from the interior 203 of carrier chassis 202 to an exterior thereof such that it may ballistically couple with a component (e.g., a detonator, an initiator) located exterior of the charge carrier 200.
In this exemplary embodiment, the rotatable member 230 of first endplate 220 is ring-shaped and thus may also be referred to herein as lock ring 230. Particularly, rotatable member 230 includes a radially outer surface 231 along which a key 232 and one or more circumferentially spaced endplate connectors 234 are positioned. Key 232 is receivable in a corresponding axially extending slot or keyway 284 (shown in
In this exemplary embodiment, first endplate 220 is transitionable from the unlocked state to the locked state by inserting locking elements 225 through apertures 229 formed in the rotatable member 222 (restricting relative rotation about central axis 205 between rotatable member 222 and locking elements 225) and coupling the locking elements 225 to an outer axial endface 223 of rotatable member 222 to restrict relative rotation about central axis 205 between locking elements 225 and rotatable member 230. For example, members 222 and 230 comprise an electrically insulating material in some embodiments that is relatively soft whereby locking elements 225 which may comprise threaded fasteners may simply be threaded into outer axial endface 233 of rotatable member 230 to bite into the rotatable member 230 secure locking elements 225 (and thereby rotatable member 222 through the locking elements 225) to the rotatable member 230.
Particularly, in this exemplary embodiment, locking elements 225 are threaded into rotatable member 230 such as into an annular lock receptacle 239 formed centrally in the outer axial end 233 of rotatable member 230 to restrict relative rotation between locked member 222 and rotatable member 230. The annular shape of lock receptacle 239 permits locking elements 225 to be threaded into lock receptacle 239 to couple locked member 222 with rotatable member 230 irrespective of the relative angular orientations of locked member 222 and locking member 230. In other embodiments, locked member 222 may instead comprise lock receptacle 239 which receive one or more locking elements 225 (e.g., extending through corresponding openings or receptacles formed in the rotatable member 230) to restrict relative rotation between locked member 222 and rotatable member 230.
The configuration of locking elements 225 and/or lock receptacle 239 may vary in other embodiments. For example, in other embodiments, locking element 225 may comprise a key receivable in corresponding receptacles of members 222 and 230 to restrict relative rotation about central axis 205 therebetween. Additionally, while in this exemplary embodiment the first endplate 220 comprises a pair of locking elements 225, in other embodiments, first endplate 220 may include only a single locking element 225 or more than two locking elements 225. Further, while in this exemplary embodiment locking elements 225 are separate from members 220 and 230 (with elements 225 forming an assembly with members 220 and 230 when in the locked state), in other embodiments, locking elements 225 may be integrally or monolithically formed with at least one of the rotatable member 222 and the rotatable member 230.
The endplate connectors 234 of the rotatable member 230 of first endplate 220 are configured to couple to a corresponding gun housing when charge carrier 200 is received therein to restrict relative axial movement (e.g., relative movement along central axis 205) between charge carrier 200 and the gun housing 200. In this exemplary embodiment, and referring now to
Particularly, the outer shoulder 236 of each endplate connector 234 is biased radially outwards such that the outer shoulder 236 flexes or springs automatically into (e.g., the endplate connector 234 may comprise a biasing element coupled to the shoulder 236) the groove 294 to secure charge carrier 200 to the gun housing 290. Endplate connectors 234 thus eliminate the need of a separate fastener such as a C-ring and the like to axially lock the charge carrier 200 to the gun housing 290, streamlining the process for assembling the perforating gun 289 leading to fewer assembly mistakes that may result in issues during downhole operation of the perforating gun 289. Particularly, instead of first installing a charge carrier followed by a separate fastener such as a C-ring, charge carrier 200 may be loaded (e.g., slid axially) into the interior of gun housing 290 until endplate connectors 234 snap automatically into the corresponding grooves 294 of gun housing 290. Additionally, in some embodiments, each endplate 220 and 250 of charge carrier 200 includes one or more endplate connectors 234 (e.g., as shown in
Referring again to
In this exemplary embodiment, electroballistic connector 240 has a longitudinal or central axis 245 (coaxial with central axis 205 in this exemplary embodiment) and is generally cylindrical, formed from electrically conductive material(s), and includes a longitudinal first or fixed end 242, a longitudinally opposed second or free end 244. Fixed end 242 is coupled the locked member 222 of first endplate 220 while free end 244 is axially spaced from the outer axial endface 223 of locked member 222 such that the free end 244 of electroballistic connector 240 projects axially from the first endplate 220 whereby the free end 244 of electroballistic connector 240 may be received in a corresponding connector (e.g., a corresponding electroballistic connector) of an external component such as a signal pod. The base end 242 of electroballistic connector 240 comprises an electrical contact or terminal 246 that flares radially outwardly and is thus radially offset from central axis 245. Electrical contact 246 may be positioned within the interior 203 of carrier 200 once assembled and electrically connected with a signal conductor of charge carrier 200, such as a signal conductor electrically connected to an electrical connector of the second endplate 250 of carrier 200.
In this exemplary embodiment, fixed end 242 of electroballistic connector 240 is open allowing the insertion of detonator cord 126 into an interior 243 of connector 240 while free end 244 is enclosed such as by an end cap formed by the free end 244. Thus, free end 244 may also be referred to herein as end cap 244. In some embodiments, end cap 244 is formed separately from electroballistic connector 240 to facilitate assembly of charge carrier 200 (e.g., to permit insertion of detonator cord 126 through free end 242). In other embodiments, end cap 244 may be formed integrally or monolithically with connector 240. The enclosure of the interior 243 of electroballistic connector 240 focuses and directs ballistic energy generated by the activation of an external ballistic component (e.g., a detonator positioned parallel and alongside the electroballistic connector 240) through one or more radial openings 248 formed along a radially outer periphery of connector 240 and against another ballistic component (e.g., an end of detonator cord 126) received in the interior 243 of electroballistic connector 240 to thereby facilitate a ballistic connection between the pair of ballistic components. Particularly, radial openings 248 may be circumferentially spaced about and/or along central axis 245 of electroballistic connector 240. In this configuration, ballistic energy which would have otherwise escaped through free end 244 is instead redirected by end cap 244 against the ballistic component received in the interior 243 of electroballistic connector 240.
The number, arrangement, location, size, shape and other characteristics of radial openings 248 may vary in other embodiments. For example, referring briefly to
Referring briefly to
Referring to
In this exemplary embodiment, signal pod 350 generally includes a pod chassis 352, and a switch 370 and a detonator 380 both received within an interior of the chassis 352. Chassis 352 extends between a first or axially inner end 351 (to the right in
Chassis 352 includes a removable alignment tab 354 which permits chassis 352 to accept detonators 380 of different longitudinal lengths. For example, the detonator 380 shown in
In this exemplary embodiment, signal pod 350 has a longitudinal or central axis 375 and generally includes a chassis 352, a switch 370, a detonator 380, a first or internal electrical connector 390, and a second or external electrical connector 410. Chassis 352 defines an internal volume or interior including a switch receptacle 357 and a detonator receptacle 359. Signal pod 350 includes an energy reflector 360 positioned in the detonator receptacle 359 and which is configured to reflect or redirect ballistic energy (shown particularly in
As shown particularly in
As shown particularly in
As shown particularly in
The presence of axial gap 366 extending between the interior of chassis 352 and the internal shoulder (or other inner surface) of the tandem sub prevents at least a limited quantity of liquid (e.g., wellbore fluids) or other dust or debris which may collect on the internal shoulder of the tandem sub from entering the interior of the chassis 352 where the liquid may interfere with the operation of switch 370 and/or detonator 380 such as by, for example, electrically shorting out various electrical signal pathways thereof. For example, as a tandem sub comprising signal pod 350 is lowered vertically through a wellbore, wellbore fluid may slowly leak across one or more seal assemblies of the toolstring comprising the tandem sub, resulting in at least some external liquid collecting within an interior of the tandem sub. Particularly, external liquid may collect along internal surfaces of the tandem sub which project vertically when the tandem sub is in a vertical orientation, such as radially extending shoulders like the internal shoulder against which the standoff legs 364 of chassis 352 engage. Thus, standoff legs 364 serve to lift the interior of chassis 352 vertically above any liquid that may collect within the space occupied by axial gap 366 as the tandem sub comprising signal pod 350 is lowered vertically through the wellbore to a desired location therein. In this manner, standoff legs 364 may assist in maintaining uninterrupted electrical signal connectivity across the signal pod 350 during the deployment thereof downhole.
In this exemplary embodiment, the switch 370 of signal pod 350 is configured to transfer a ballistic signal to a targeted perforating gun coupled to the signal pod 350 to detonate one or more shaped charges of the targeted perforating gun in response to receiving a firing signal associated with the signal pod 350, such as a firing signal addressed to (e.g., uniquely or specifically addressed to) the switch 370 of signal pod 350. In other embodiments, the switch of a given signal pod (e.g., switch 370 of signal pod 350) may perform actions downhole in addition to or other than transferring ballistic signals to the targeted perforating gun. For example, the switch of the signal pod may instead transmit one or more electrical and/or ballistic signals to one or more other pieces of equipment coupled therewith in response to receiving an appropriate command signal. For instance, the switch may instead activate a setting tool of a toolstring incorporating the signal pod 350.
Referring briefly now to
In some embodiments, switch 412 of signal pod 410 may activate the setting tool (e.g., via igniting setting tool igniter 420) in response to receiving (e.g., from a surface assembly) a first or setting signal, and may detonate the perforating gun 279 coupled to the uphole end 402 of tandem sub 400 in response to receiving (e.g., from the surface assembly) a second or firing signal that is different from the setting signal. In certain embodiments, while the firing signal may be different from the setting signal (e.g., including different instructions or substantive content), both the firing signal and the setting signal may be addressed (e.g., specifically or uniquely addressed) to the same signal pod 410. For example, the firing and setting signals may be addressed to the same switch 412 where, in certain embodiments, switch 412 may comprise a plurality of separate electrical or electronics witches contained in the same signal pod 410 such as being positioned on the same PCB. Therefore, in some embodiments, the setting signal may be addressed to a first switch of signal pod 410 while the firing signal is addressed to a second switch of signal pod 410. Thus, in this manner, switch 412 of signal pod 410 provides for a dual functionality of activating both a setting tool and a perforating gun of a toolstring comprising the signal pod 410 by transmitting both setting and firing signals (e.g., at different points in time) to the same switch 412. Thus, in this manner, switch 412 of signal pod 410 provides for a dual functionality of activating both a setting tool and a perforating gun of a toolstring comprising the signal pod 410 by transmitting both setting and firing signals (e.g., at different points in time) to the same switch 412.
Along with a signal pod such as signal pod 350 shown in
Referring now to
The pressure bulkhead 450 shown in
Bulkhead insulator 460 is overmolded to a radially outer surface 453 of the bulkhead conductor 452 to seal the generally annular interface formed therebetween. Particularly, in this exemplary embodiment, a radially outwards projecting shoulder 455 is formed along the outer surface 453 to resist decoupling (e.g., in response to the application of intense axially directed forces to the pressure bulkhead 450 during operation) or detachment of the bulkhead insulator 460 from the bulkhead conductor 452. In some embodiments, the outer shoulder 455 of bulkhead conductor 452 defines a maximum OD of the bulkhead conductor 452 that is greater than the OD of the bulkhead conductor 452 extending axially from shoulder 455 to the pin connector 454 of conductor 452. In this configuration, interference between outer shoulder 455 of bulkhead conductor 452 and a radially inner surface or ID of bulkhead insulator 470 increases the strength (e.g., resilience to axially directed loads) of the coupling formed between bulkhead conductor 452 and bulkhead insulator 460.
In some applications, it may be preferable to rely on a rigid insulator for the pressure bulkhead rather than an overmolded insulator in order to even minimize the potential for physical separation of the insulator and conductor of the pressure bulkhead. The pressure bulkhead 500 shown in
Specifically, in this exemplary embodiment, bulkhead insulator 510 is formed from two separate insulator members—an outer insulator body 512 and an insulator endcap 514 longitudinally opposite insulator body 512. Insulator body 512 at least partially encloses and electrically insulates the pin connector 504 and the intermediate portion of bulkhead connector 502 extending from pin connector 504 towards box connector while the insulator endcap 514 at least partially encloses and electrically insulates the opposing longitudinal end of bulkhead conductor 502 that forms box connector 506. In some embodiments, insulator endcap 514 may not be directly attached or secured to the insulator body 512, and instead, endcap 514 may be free to travel or slide axially relative to body 512. Instead, relative axial movement between insulator members 512 and 514, and bulkhead conductor 502 may be restricted via engagement between these members and components external pressure bulkhead 500 such as the surrounding tandem sub and/or other components such that members 502, 512, and 514 remain axially locked together.
The pressure bulkhead 550 shown in
Thus, the insulator body 512 of pressure bulkhead 500 has been effectively split, in this exemplary embodiment, into the separate insulator sleeve 562 and first insulator endcap 564. In this manner, any cracks or other damage that forms in the first insulator endcap 564 (e.g., as a result of axially directed impact forces during operation) cannot propagate across the interface formed between the insulator sleeve 562 and first insulator endcap 564. Instead, cracks formed in first insulator endcap 564 must terminate at the inner longitudinal end (e.g., the end adjacent insulator sleeve 562), thereby preserving the structural integrity of insulator sleeve 562 to maintain the operability of pressure bulkhead 550 in spite of the occurrence of damage (e.g., cracking) in the first insulator endcap 564.
Referring to
Turning to
In this exemplary embodiment, the exterior chassis 712 of signal pod 710 orients detonator 720 at a non-zero inclination angle (e.g., an acute angle) to longitudinal axis 715 in order to focus the peak ballistic energy generated by detonator 720 in the direction of the detonator cord housing 240 which is laterally spaced (relative longitudinal axis 715) from detonator 720. Ballistic energy produced by detonator 720 may not be uniform but rather biased or focused at a distal end 722 of detonator 720 opposite a pair of electrical contacts 724 of detonator 720 as shown in
Turning to
Turning now to
Particularly, the charge carrier 800 shown in
In this exemplary embodiment, second member 810 comprises a spring cover that is coupled to the proximal side 803 of outer member 804 by one or more fasteners (e.g., threaded fasteners such as screw fasteners) 806 forming a compartment or cavity 809 longitudinally between the distal side 807 of second member 810 and the proximal side 803 of first member 804. The proximal end 822 of detonator cord housing is received in cavity 809, trapped between the distal side 807 of second member 810 and the proximal side 803 of first member 804. Additionally, in this exemplary embodiment, each fastener 806 each “spring loaded” or biased longitudinally outwards against the distal side 807 of second member 810 and the proximal side 803 of first member by one or more corresponding mechanical springs or biasing members 808 which are positioned or extend around their corresponding fasteners 806. In this exemplary embodiment, biasing members may comprise metallic springs such as coil springs, washers, and the like. However, the configuration of biasing members 808 may vary in other embodiments.
Biasing members 808 press the proximal end 822 of detonator cord housing 820 against the proximal side 803 of first member 810 to maintain electrical contact therebetween in spite of vibration and other environmental effects that could otherwise break the electrical connection formed between endplate 802 and detonator cord housing 820. Additionally, biasing members 808 permit second member 810 to move (e.g., by a predefined degree) relative to first member 804 whereby the longitudinal axis 825 of detonator cord housing 820 is permitted to angularly misalign with the longitudinal axis 805 of endplate 802 whereby a non-zero misalignment angle 811 (e.g., an acute angle) is formable between axes 805 and 825. For example, a bending moment applied to the distal end 824 of detonator cord housing 820 may result in rotation (e.g., about one or more lateral or radially extending axes relative longitudinal axis 805) of detonator cord housing 820 relative to endplate 802 thereby forming misalignment angle 811. In some embodiments, the misalignment angle 811 is approximately between. In addition to permitting the formation of misalignment angle 811, biasing members 808 also provide a restoring torque to detonator cord housing 820 in response to the formation of misalignment angle 811, the restoring torque urging detonator cord housing 820 back into alignment (with misalignment angle 811 being eliminated or reaching substantially zero) with the longitudinal axis 805 of endplate 802.
The charge carrier 850 shown in
Particularly, in this exemplary embodiment, charge carrier 850 additionally includes a generally spherical or “ball” connector 880 located in a generally spherical compartment 859 that is formed longitudinally between first member 854 and second member 856 of endplate 852. Ball connector 880 is coupled to the proximal end 872 of detonator cord housing 870 such that ball connector 880 and detonator cord housing 870 are pivotable in concert relative to endplate 852. Given that ball connector 880 is at least partially defined by a spherical outer surface while compartment 859 is at least partially defined by a corresponding spherical inner surface, ball connector 880 along with detonator cord housing 870 are permitted to rotate about an unlimited number of axes relative to members 854 and 856 of endplate 852. In other words, ball connector 880 and spherical compartment 859 form a ball joint between the endplate 852 and detonator cord housing 874.
Additionally, in this exemplary embodiment, charge carrier 850 comprises one or more biasing members 890 positioned in spherical compartment 859 extending circumferentially around (e.g., continuously as a single biasing member 890 or arcuately as a plurality of circumferentially spaced biasing members 890) ball connector 880 to provide a restoring torque to the detonator cord housing 870 urging a longitudinal axis 875 of housing 870 towards a longitudinal axis 855 of endplate 852 in response to pivoting of the detonator cord housing 870 relative to endplate 850. Additionally, given that biasing members 890 extend circumferentially around ball connector 880 (e.g., and is thus circumferentially symmetrical in some embodiments), biasing members 890 are configured to provide a substantially equal restoring force to the detonator cord housing 870 irrespective of the direction (e.g., the azimuth) of the misalignment formed between the longitudinal axes of endplate 852 and detonator cord housing 870. In this exemplary embodiment, biasing members 890 may comprise metallic springs such as coil springs, washers, and the like. However, the configuration of biasing members 890 may vary in other embodiments.
In some embodiments, ball connector 880 is configured to move or pivot freely within the spherical compartment 859 of endplate 852 while also having a somewhat loose fit therein to additionally accommodate radial movement of the proximal end 872 within spherical compartment 859 whereby a non-zero radial or lateral offset is formable (e.g., in response to the application of a laterally directed force against the detonator cord housing 870) between the longitudinal axis 855 of endplate 852 and the longitudinal axis 875 of detonator cord housing 870. Thus, in some embodiments, both a misalignment angle and/or a radial offset may form between axes 855 and 875 in response to the application of external forces to detonator cord housing 870 where this additional degree of flexibility minimizes the potential for the application of excessive stress to the detonator cord housing 870 which could damage or otherwise interfere with the desired operation of housing 870.
The charge carrier 900 shown in
The charge carrier 920 shown in
The charge carrier 950 shown in
One particularly important aspect of the embodiments of perforating gun systems disclosed herein is that they do not require any angular clocking or adjustment of rotational orientation to assemble. As such, embodiments of perforating gun systems described herein are amenable to automated or at least partially-automated assembly to streamline the process of assembling the perforating gun systems in the field.
Referring now to
In this exemplary embodiment, system 1000 generally includes a transportable (e.g., road transportable) vehicle or trailer 1002, a support platform 1010, a toolstring equipment conveyor 1020, and an at least partially automated tool assembler or loader 1030. Trailer 1002 may provide sufficient space for transporting toolstring equipment while also providing shelter to operators of the toolstring when out in the field where ambient conditions can be extreme (e.g., extreme temperatures, weather events). For example, trailer 1002 may be enclosable from the surrounding environment and may include heating, ventilation, and air-conditioning (HVAC) equipment for regulating the internal environment of the trailer 1002.
In this exemplary embodiment, equipment of a toolstring (e.g., toolstring 30 shown in
While allowing for the convenient pre-wiring of the shaped charges 125 and detonating cord 126 of the perforating gun system 37 prior to transport to the wellsite 1001, the transport state of each perforating gun system 37 also ensures the given perforating gun system 37 is safe for transport (e.g., to ensure the shaped charges 125 of the perforating gun systems 37 are not inadvertently detonated) to the wellsite 1001 and, in some applications, to comply with applicable transportation regulations governing transportation routes (e.g., public roadways and the like) used when transporting the perforating gun systems 37 to the wellsite 1001. Particularly, in this exemplary embodiment, in the transport state of each perforating gun system 37 the detonator cord 126 and the shaped charges 125 thereof are each ballistically decoupled (e.g., not in ballistic communication) from the detonator 158 of the perforating gun system 37 such that the detonator 158 may not inadvertently detonate or otherwise activate either the detonating cord 126 or the shaped charges 125 of the perforating gun system 37.
The associated equipment of system 1000 including, for example, support platform 1010, toolstring equipment conveyor 1020, and tool assembler 1030 facilitate the transformation of perforating gun systems 37 (transported or shipped from a remote location in trailer 1002 while in the transport state) from the transport state to a deployment state or configuration following the arrival of the perforating gun systems 37 to the wellsite 1001. In this exemplary embodiment, when in the deployment state, the detonator of the perforating gun system 37 enters into ballistic communication (e.g., becomes ballistically coupled) with the corresponding detonating cord 126 and shaped charges 125 of the system 37. In some embodiments, when in the deployment state, the shaped charges 125 may be detonated automatically in response to the electrical switch 155 of the perforating gun receiving an appropriate firing signal.
In some embodiments, support platform 1010, toolstring equipment conveyor 1020, and tool assembler 1030 may also facilitate the assembly of the toolstring comprising the plurality of perforating gun systems 37 transported to the wellsite 1001 in trailer 1002, where the assembled toolstring may be lifted and deployed into a wellbore using a corresponding deployment system such as a wireline system (e.g., wireline system 5 shown in
In this exemplary embodiment, support platform 1010 comprises a platform upon which toolstring equipment, including the plurality of perforating guns transported to the wellsite 1001 in the transport state, may be laid out prior to assembly or for other sundry uses. Additionally, in this exemplary embodiment, toolstring equipment conveyor 1020 provides an elongate path or track 1022 along which toolstring equipment may be transported as it is assembled by the tool assembler 1030. In this exemplary embodiment, toolstring equipment conveyor 1020 simply comprises a plurality of angled supports for directing the assembled toolstring equipment along the assembly track 1022. Alternatively, toolstring equipment conveyor 1020 may comprise a powered conveyor (e.g., a conveyor belt and the like) for transporting the assembled toolstring equipment in the direction of the wellbore of the wellsite 1001.
In this exemplary embodiment, tool loader 1030 generally includes a loading track 1032, a linear actuator 1034, and a rotary actuator 1040. In some embodiments, the equipment of tool loader 1030 such as, for example, actuators 1034 and 1040 are operated by a computer system or controller, such as one located in trailer 1002 or even remote of the wellsite 1001. Toolstring equipment such as perforating gun systems 37 may be initially loaded onto the loading track 1032 as a staging location for the perforating gun systems 37 prior to being loaded onto toolstring equipment conveyor 1020. Particularly, in this exemplary embodiment, each of the perforating gun systems 37 may be initially assembled (e.g., at the support platform 1010) into perforating gun kits 1005 each comprising an uphole tandem sub 50A, a downhole perforating gun 35B, and a perforating gun system 37 sandwiched or coupled (e.g., rotatably or threadably coupled) between the uphole tandem sub 50A and the downhole perforating gun 35B. In some embodiments, the resulting toolstring may comprise a plurality of the assembled perforating gun kits 1005 positioned therealong.
In some embodiments, forming perforating gun kits 1005 may include transitioning at least some of the perforating gun systems 37 from the transport state to the deployment state. Referring briefly to
In this exemplary embodiment, the perforating gun system 37A is transitioned at the wellsite 1001 from the transport state to the deployment state automatically by mechanically coupling the pre-assembled perforating gun kit comprising tandem sub 50A/perforating gun 35B to the downhole end of perforating gun 35A whereby the shaped charges 125 of perforating gun 35A automatically enter into ballistic communication with the corresponding detonator 158 of the signal pod 150 of tandem sub 50A. For example, torque may be applied (via a tool or manually) to the exterior of the pre-assembled perforating gun kit to rotatably and threadably connect the perforating gun kit with the downhole end of perforating gun 35A. However, the means by which the perforating gun kit comprising tandem sub 50A is coupled with perforating gun 35A to transition perforating gun system 37A from the transport state to the deployment state may vary in other embodiments.
Returning to
Although the transportation of perforating gun systems from a remote site to wellsite 1001 in a transport state and subsequently transitioning the perforating gun systems 37 following their arrival at the wellsite 1001 to the deployment state in the context of system 1000, in other embodiments, different systems may be employed for transporting perforating gun systems 37 to the wellsite 1001 and/or for loading and assembling the transported perforating gun systems 37 into a toolstring. For example, in some embodiments, the different perforating gun systems 37 may be manually loaded and assembled at the wellsite 1001 rather than utilizing an at least partially automated system such as system 1000.
The relative dimensions of various parts, the materials from which the various parts are made, and other parameters can be varied. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.
This application claims benefit of U.S. provisional patent application No. 63/525,948 filed Jul. 10, 2024, U.S. provisional patent application No. 63/634,406 filed Apr. 15, 2024 and U.S. provisional patent application No. 63/643,228 filed May 6, 2024, all entitled “Switch Module for Wellbore Perforating Gun”, and all of which are incorporated herein in their entirety for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 63525948 | Jul 2023 | US | |
| 63634406 | Apr 2024 | US | |
| 63643228 | May 2024 | US |
