(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2016/0084048 A1
`
` Harrigan et al. (43) Pub. Date: Mar. 24, 2016
`
`
`US 20160084048A1
`
`(54) COHESIVELY ENHANCED MODULAR
`PERFORATING GUN
`
`Publication Classification
`
`(71) Applicant: SCHLUMBERGER TECHNOLOGY
`CORPORATION, Sugar Land, TX (US)
`
`(72)
`
`Inventors: Edward Harrigan, Richmond, TX (US);
`Hao Liu Missouri City TX (US): Vinod
`Chakka, Pune (IN); Richard Warns,
`Sugar Land, TX (US); Pedro
`Hernandez, Sugar Land, TX (US);
`Raphael Rogman, Houston, TX (US);
`Allan Goldberg, Alvin, TX (US)
`
`(21) Appl. No.:
`
`14/888,882
`
`(22) PCT Filed:
`.
`(86) PCT NO"
`§ 371 (c)(1),
`(2) Date:
`
`May 2, 2014
`
`PCT/US14/36541
`
`Nov. 3, 2015
`.
`.
`Related US Application Data
`(60) Provisional application No. 61/819,196, filed on May
`3, 2013.
`
`(51)
`
`Int. Cl.
`E213 43/1185
`E213 43/11 7
`(52) US. Cl.
`CPC ........... E213 43/1185 (2013.01); E213 43/117
`(201301)
`
`(2006.01)
`(2006.01)
`
`(57)
`
`ABSTRACT
`
`Embodiments may take the form of a perforating gun of
`modular assembly. The perforating gun may include at least
`one centralizing member at an interface between a loading
`tube and a carrier. Among modular components, the gun may
`also include an initiator assembly module that is electrically
`coupled to a modular feedthrough with a connector. The
`insert and the centralizing member may enhance axial cohe-
`siveness of the modular gun. A shock absorbing mount may
`be located within the carrier and may receiving the initiator
`assembly module to provide added axial cohesiveness to the
`modular gun.
`
`
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 001
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 001
`
`

`

`Patent Application Publication Mar. 24, 2016 Sheet 1 0f 5
`
`US 2016/0084048 A1
`
`
`
`
`/
`
`133
`z
`
`”533
`j
`
`
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 002
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 002
`
`

`

`Patent Application Publication
`
`Mar. 24, 2016 Sheet 2 0f 5
`
`US 2016/0084048 A1
`
`Wm
`
`.wwmw
`
`
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 003
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 003
`
`

`

`Patent Application Publication Mar. 24, 2016 Sheet 3 0f 5
`
`US 2016/0084048 A1
`
`
`
`554$.
`
`35%
`
`
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 004
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 004
`
`

`

`Patent Application Publication Mar. 24, 2016 Sheet 4 0f 5
`
`US 2016/0084048 A1
`
`
`
`Fifi?-
`
`47A
`
`
`
`FHA 4f}
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 005
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 005
`
`

`

`Patent Application Publication Mar. 24, 2016 Sheet 5 0f 5
`
`US 2016/0084048 A1
`
`
`
`Fifi
`
`57A
`
`
`
`FEE-'21,.
`
`5%?
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 006
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 006
`
`

`

`US 2016/0084048 A1
`
`Mar. 24, 2016
`
`COHESIVELY ENHANCED MODULAR
`PERFORATING GUN
`
`PRIORITY CLAIM/CROSS REFERENCE TO
`
`RELATED APPLICATION(S)
`
`[0001] This Patent Document claims priority under 35 US.
`C. §119 to US. Provisional App. Ser. No. 61/819,196, filed
`May 3, 2013, and entitled, “Perforating Gun with Integrated
`Initiator”, which is incorporated herein by reference in its
`entirety.
`
`BACKGROUND
`
`[0002] Exploring, drilling and completing hydrocarbon
`and other wells are generally complicated, time consuming
`and ultimately very expensive endeavors. As a result, over the
`years well architecture has become more sophisticated where
`appropriate in order to help enhance access to underground
`hydrocarbon reserves. For example, as opposed to wells of
`limited depth, it is not uncommon to find hydrocarbon wells
`exceeding 30,000 feet in depth. Furthermore, as opposed to
`remaining entirely vertical, today’s hydrocarbon wells often
`include deviated or horizontal sections aimed at targeting
`particular underground reserves.
`[0003] While such well depths and architecture may
`increase the likelihood of accessing underground hydrocar-
`bon reservoirs, other challenges are presented in terms ofwell
`management and the maximization of hydrocarbon recovery
`from such wells. For example, during the life of a well, a
`variety of well access applications may be performed within
`the well with a host ofdifferent tools or measurement devices.
`
`However, providing downhole access to wells of such chal-
`lenging architecture may require more than simply dropping
`a wireline into the well with the applicable tool located at the
`end thereof. Indeed, a variety of isolating, perforating and
`stimulating applications may be employed in conjunction
`with completions operations.
`[0004]
`In the case ofperforating, different zones ofthe well
`may be outfitted with packers and other hardware, in part for
`sake of zonal isolation. Thus, wireline or other conveyance
`may be directed to a given zone and a perforating gun
`employed to create perforation tunnels through the well cas-
`ing. As a result, perforations may be formed into the sur-
`rounding formation, ultimately enhancing recovery there-
`from.
`
`[0005] The described manner of perforating requires first
`that the perforating gun be loaded with a number of shaped
`charges that provide the energy to form the noted perforation.
`Specifically, an explosive pellet of compressed material is
`provided in a casing and may be individually loaded into the
`gun as a shaped charge. Thus, once detonated, each shaped
`charge may perform similar to a ballistic jet in forming an
`adjacent perforation. Further, this manner of operation is
`enhanced by a liner that is placed over the explosive pellet.
`That is, the pellet is secured within the cavity of a casing and
`provided with a liner thereover so as to enhance and tailor the
`performance of the fully assembled shaped charge.
`[0006] Unfortunately, while fairly safe and effective foruse
`downhole in the well, transporting a fully armed gun loaded
`with a detonator and shaped charges to an operator at an
`oilfield is not an option. Indeed, as a matter of ensuring safe
`transport, governmental bodies, such as the department of
`transportation (DOT) in the United States, understandably do
`not allow the transporting of such an assembly unless it is
`
`modified, for example with a cumbersome ballistic interrupt.
`More likely, components of the unarmed gun and detonator
`are separately delivered to the oilfield location where assem-
`bly may be completed prior to deployment of the gun into the
`well.
`
`[0007] Arming and fully assembling a perforating gun with
`a detonator at the oilfield may be a time consuming and
`largely inexact undertaking. For example, shaped charges
`may be assembled and/or loaded into a loading tube that
`accommodates a host of charges and is then inserted into a
`carrier of the gun. However, even the loaded gun remains
`incomplete. That is, as a matter of added precaution, an im-
`tiator that regulates firing of the gun is generally not effec-
`tively wired to the gun until all required components are
`present and assembled.
`[0008] The initiator is a circuit-based device that is config-
`ured to detect an operator’s command from the oilfield sur-
`face in order to allow detonation of the shaped charges within
`the gun. Thus, in order to keep the gun less than fully armed,
`it may be provided at the oilfield without the initiator but with
`an exposed port where the initiator is to be added. At this
`location, wiring in a downhole direction to an internal deto-
`nator may be found as well as wiring that runs in an uphole
`direction for sake of conveying operator commands. As a
`practical matter, this means that a host of different wires are
`manually connected to corresponding connections or wires of
`the initiator by hand as the port of the gun remains open to the
`oilfield surface environment.
`
`[0009] Not only is this type of assembly time consuming as
`noted above, there remains the possibility of mis-wiring,
`debris getting into the gun, or even improper sealing and/or
`capping off of the initiator once the connections have been
`made. Indeed, it is estimated that a majority of perforating
`application misruns may be linked directly to such wiring
`related issues. This may be attributable to human error or
`simply the inherent lack of cohesiveness involved where mul-
`tiple electrical connections are made at the oilfield. Whatever
`the case, a degree of reliability is compromised, in order to
`ensure an acceptable level safety.
`
`SUMMARY
`
`[0010] A modular perforating gun is disclosed for perforat-
`ing a formation in a well. The gun includes a tubular carrier
`with a loading tube therein. The loading tube includes a shock
`absorbing mount with shaped charges to one side of the
`mount and an initiator assembly module at an opposite side
`thereof. The initiator assembly module is configured to trig-
`ger the charges for the perforating. Further, at least one cen-
`tralizing member is disposed about the loading tube to pro-
`vide a secure interface between the tubular carrier and the
`
`loading tube. In one embodiment, a modular feedthru assem-
`bly is also provided that securably receives an electrical con-
`nector of the initiator assembly at an interface therebetween.
`Thus, coupling between the connector and feedthru assembly
`may be enhanced.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1A is an exploded perspective view of an
`[0011]
`embodiment of a cohesively enhanced modular perforating
`gun.
`
`FIG. 1B is an overview of an oilfield with a well
`[0012]
`accommodating the perforating gun of FIG. 1A.
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 007
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 007
`
`

`

`US 2016/0084048 A1
`
`Mar. 24, 2016
`
`FIG. 2A is a side cross-sectional view ofthe perfo-
`[0013]
`rating gun showing chamfered centralizing rings ensuring
`cohesive fit between a loading tube and carrier.
`[0014]
`FIG. 2B is an enlarged view ofthe perforating gun of
`FIG. 2A revealing detail of a centralizing ring interface
`between the loading tube and carrier.
`[0015]
`FIG. 3A is a perspective view of an embodiment of
`an initiator assembly module configured for plugging into the
`loading tube of FIG. 2A.
`[0016]
`FIG. 3B is a perspective view ofthe module ofFIG.
`3A plugged into the loading tube and wired in place utilizing
`an embodiment of retention clips.
`[0017]
`FIG. 4A is a perspective view of a shock absorbing
`mount for securing in the loading tube to receive the module
`of FIGS. 3A and 3B.
`
`FIG. 4B is a side cross-sectional view ofthe loading
`[0018]
`tube within the carrier of FIG. 1A with the mount of FIG. 4A
`secured therein.
`
`FIG. 5A is a side cross-sectional view ofan embodi-
`[0019]
`ment of a modular feedthru assembly for coupling a bulkhead
`to the initiator assembly module of FIGS. 3A and 3B.
`[0020]
`FIG. 5B is a perspective view of an embodiment of
`a compressible barrel insert of the feedthru assembly of FIG.
`5A to enhance the coupling between the bulkhead and initia-
`tor assembly module.
`
`DETAILED DESCRIPTION
`
`[0021] Embodiments are described with reference to cer-
`tain perforating applications. For example, in embodiments
`shown, a single wireline conveyed perforating gun is deliv-
`ered to a vertical well for a perforating application. However,
`in other embodiments, the gun may be conveyed by alternate
`means, incorporated into more permanent hardware, pro-
`vided in series or a host of other operational types. Regard-
`less, so long as the perforating gun is modular in nature with
`certain structurally and/or electrically stabilizing features as
`detailed herein, appreciable benefit may be realized. Specifi-
`cally, such features may render a modular form of assembled
`perforating gun both user-friendly and practically reliable for
`the environment of a downhole perforating application and
`transport thereto.
`[0022] Referring now to FIG. 1, an exploded perspective
`view of an embodiment of a cohesively enhanced modular
`perforating gun 100 is shown. In this embodiment, modular
`components include a carrier 110 that
`is configured for
`accommodating a loading tube 115. The loading tube 115 is
`configured to accommodate a host of shaped charges for a
`perforating application in a well 180 (see FIG. 1B). However,
`in the embodiment shown, the loading tube 115 is also con-
`figured to accommodate an initiator assembly module 125.
`That is, rather than utilizing externally wired initiator and
`detonator components, manually wired to the gun 100 at the
`oilfield, a single pre-wired subassembly package 125 of such
`functionality may be plugged into the loading tube 115.
`[0023] As detailed further below, even though plugged in,
`the module 125 includes safety features to prevent accidental
`detonation and is provided to the oilfield in an unarmed state.
`Specifically, with added reference to FIGS. 3A, 3B, and 4A
`even though the module 125 is outfitted with a detonator 301,
`a shutter 479 is provided that prevents full arming of the gun
`100. Thus, in order to fully arm the gun 100, a sequenced
`command is required to displace the shutter 479 and allow the
`gun 100 to be fired once the proper instruction is placed.
`
`[0024] Continuing with reference to FIG. 1A, the carrier
`110 and loading tube 115 may be sealed off at either end by
`bulkheads 117, 118. Thus, explosive shaped charges may be
`safely isolated within the downhole environment until the
`time of the perforating application (see FIG. 1B). Further,
`each bulkhead 117, 118 may have a modular feedthru 119,
`120 to ultimately provide electrically connectivity between
`internal components such as the initiator assembly module
`125 and communications from surface. Thus, signature com-
`mands from surface may reach the initiator assembly module
`125 to trigger perforating as noted above.
`[0025] The modular nature of each feedthru 119, 120 may
`be rendered reliably secure and practical by the addition of
`barrel inserts 500 to enhance the interface between electrical
`
`connector 530 and a body 580 of the feedthru 119, 120 (see
`FIG. 5). Similarly, as also detailed further below, interfacing
`between the carrier 110 and loading tube 115 may be securely
`enhanced by the use of one or more centralizing members,
`such as rings 200 about the loading tube 115 (see FIGS. 2A
`and 2B). It should be appreciated that other embodiments
`may employ other centralizing features, such as flanges,
`standoffs, pegs, protrusions, and so forth, for example.
`[0026] The above noted bulkheads 117, 118 may also serve
`as adapters where crossovers 130, 140 may be secured for
`providing secure communicating connection to other modu-
`lar components. For example, in the embodiment shown, a
`plug and shoot module 133 and handling cap 137 are secured
`to one crossover 130 and may in turn provide connection to a
`setting tool or other device. However, at the other end, the
`crossover 140 may couple to a head 145 providing connection
`to a correlation tool or other device.
`
`[0027] Referring specifically now to FIG. 1B, an overview
`of an oilfield 101 is shown with a well 180 accommodating
`the perforating gun of FIG. 1A. The modular gun 100 may be
`assembled offsite in a controlled location before delivery to
`the oilfield 101. Thus, the gun 100, and in particular, the
`initiator assembly module 125 may be delivered in a pre-
`wired manner with a detonator 301 in place (see FIG. 3A). As
`noted above, the module 125 may be armed and/or disarmed
`once reaching the oilfield. As opposed to challenging manual
`wiring and/or disconnecting, arming and disarming may take
`place in a user friendly manner as described above and
`detailed further herein. With this type of modular gun 100
`available, misruns due to manual error in assembly at the
`oilfield may be eliminated and a manner ofrapid deployment
`provided.
`[0028] Once armed at the module 125 and secured to a
`wireline cable 160, the gun 100 may be deployed. As opposed
`to hours ofwiring and assembling time before use in a well, in
`the embodiment shown, the armed gun 100 may be hooked
`up, a brief electronics diagnostic check run, and the gun 100
`deployed as noted from a reel 155 at a wireline truck 150.
`Guidance from a control unit 165 and supportive rig 170 may
`be utilized as the gun 100 is advanced past a wellhead 175 and
`various formation layers 190, 195 before perforating is
`directed through casing 185 defining the well 180.
`[0029] The entire modular gun 100 may be disposable even
`after a single perforating application as described. That is, the
`ability to use low-cost modular components that fit multiple
`gun sizes may minimize concern over disposal of the system
`after perforating is complete. Thus, time lost to cleaning and
`refurbishing parts may be largely avoided.
`[0030] Referring now, to FIGS. 2A and 2B, more internal
`structure of the gun 100 is shown which allows for such
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 008
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 008
`
`

`

`US 2016/0084048 A1
`
`Mar. 24, 2016
`
`reliable and inexpensive modular construction. Specifically,
`FIG. 2A is a side cross-sectional view of the perforating gun
`100 showing chamfered centralizing rings 200 that help to
`ensure a cohesive fit between the loading tube 115 and carrier
`110. These types of rings 200 may also serve as an aid to
`connector engagement or as standoffs relative more internal
`shaped charges.
`[0031]
`In the view of FIG. 2A, the above referenced modu-
`lar components ofthe gun 100 are visible in a fully assembled
`form. Specifically, the bulkheads 117, 118 are threadably or
`otherwise secured to crossovers 130, 140 with a feedthru 119,
`120 disposed through each bulkhead 117, 118 to support
`continuous communicative connection through the gun 100.
`Continued threadable connection between, and/or among, the
`crossovers 130, 140 and more distal components of the plug
`and shoot module 133, handling cap 137 and head 145 allow
`for an overall modular gun assembly.
`[0032]
`In the embodiment shown, the inner surface of the
`loading tube 115 may include a variety of different fasteners
`215 for securing communicative line that traverses the length
`of the tube 115. That is, given that communications from
`bulkhead 117 to bulkhead 118 and beyond are wired through
`the tube 115, it may nevertheless be advantageous to retain
`such wiring away from certain locations of the loading tube
`115 such as at the central axis, at shaped charge locations, etc.
`Thus, this particular wiring or line may be spiraled through
`the loading tube 115 and held by securely at predetermined
`locations by the noted fasteners 215.
`[0033] Completing the gun 100 by way ofjoining the bulk-
`heads 117, 118 to the carrier 110 is preceded by loading ofthe
`loading tube 115 into the carrier 110 once the initiator assem-
`bly module 125 is securely in place. That is, the module 125
`is plugged into the loading tube 115, the loading tube 115
`inserted into the carrier 110 and the bulkheads 117, 119
`secured thereto. Of course, different types of initiator mod-
`ules may be interchangeably utilized depending on the type of
`perforating application to be run.
`[0034]
`In the embodiment shown, positioning the loading
`tube 115 into the carrier 110 includes the placement of cen-
`tralizing rings 200 between the carrier 110 and the loading
`tube 115 as the two are brought together. The centralizing
`rings 200 may be of a durable plastic or other suitable material
`that serve to dampen impacts and vibrations that will occur as
`the gun 100 is transported or deployed into the well. So, for
`example, the possibility of damage to electronics of the ini-
`tiator assembly module 125 within the loading tube 115 may
`be lessened.
`
`In addition to the protective support provided by
`[0035]
`centralizing rings 200, they also may be used to ensure a
`cost-effective and proper sizing match between the loading
`tube 115 and carrier 110. That is, as opposed to requiring a
`near perfectly fitted size match between the modular tube 115
`and carrier 110 components, centralizing rings 200 may
`effectively serve to provide the proper size match. That is,
`even with a host of differently sized loading tubes 115 and
`carriers 110 available, an inexpensive plastic, but properly
`sized set of rings 200 may more than adequately serve to
`provide a matching interface between the modular tube 115
`and carrier 110. Additionally, in one embodiment, the rings
`200 may be located at an interface between the carrier 110 and
`a bulkhead 117, 118 or other feature coupled to the loading
`tube 115. That is, in such an embodiment, the rings 200 would
`still remain within the carrier 110 while supporting and cen-
`tralizing the tube 115.
`
`[0036] Continuing with added reference to FIG. 2B, at least
`one end of each centralizing ring 200 is chamfered 225
`inwardly. Thus, placement of a ring 200 about the loading
`tube 115 may be promoted. For example, in one embodiment
`a ring 200 may be located within the carrier 110 at the end
`opposite the initiator assembly module 125 with the cham-
`fered end 225 facing the direction of the module 125. The
`loading tube 115 may then be inserted into the carrier 110 and
`deflectably guided into position, through the ring orifice 280
`by the chamfered end 225 of the ring 200. With the module
`125 already loaded into the tube 115 and the centralizing ring
`200 already in place thereover, the bulkhead 117 may then be
`secured to the carrier 110 and the modular gun 100 com-
`pleted. In one embodiment, the centralizing ring 200 may be
`chamfered on both ends and not directionally dependent.
`Additionally, rings 200 may include standoffs supported by
`the inner wall of the carrier 110 as well as a host of other
`features.
`
`[0037] Referring now to FIGS. 3A and 3B, with added
`reference to FIGS. 1A and 1B, additional features are
`described which add to the practicality of using a linked
`together, modular concept for a gun 100 as described. Spe-
`cifically, as alluded to above, the initiator assembly module
`125 affords advantages related to reducing the amount of
`manual wiring and assembly that takes place at an oilfield
`101. It includes features that mitigate the risk of accidental
`detonation, for example, due to stray voltage. Additionally,
`while a detonator 101 is provided as part of the module 125,
`added measures may be taken to ensure proper alignment and
`retention of the detonator 301 during handling and use of the
`gun 1 00.
`[0038] With specific reference to FIG. 3B, a retaining clip
`300 is shown that may be directed toward the initiator assem-
`bly module 125 via a cutaway 310 in the loading tube 115.
`That is, recalling that in the embodiment shown, the module
`125 is at least partially inserted into the tube 115, the cutaway
`310 in the tube may provide manual access to the module 125
`for sake of continued accessibility. For example,
`in the
`embodiment shown, a retention clip 300 may be placed
`through the cutaway 310 to secure permanent retention and
`engagement of the detonator 301 within the module 125.
`Thus, detonator movement and misalignment from shock
`over the course of handling and using the gun 100 may be
`avoided. Snap-fitting of the clip 300 may involve no more
`than properly aligning tabs 375 relative the detonator 301 and
`module body 125. Thus, a user-friendly, sandwich-like
`engagement of the detonator 301 may be permanently
`ensured. Additionally, the clip 300 snaps securely into place
`with an upper surface 350 that is left flush with, or below the
`outer diameter of the loading tube 115. This manner of snap-
`ping into place may include a one direction insertion with the
`clip 300 keyed such that accidental removal or dislodging is
`prevented. Therefore, the gun 100 is secure with the clip 300
`out of the way.
`[0039] Referring now to FIGS. 4A and 4B, features that
`allow the initiator assembly module 125 to be securely and
`stably accommodated in modular form are shown. Recalling
`that the module 125 operates as a ballistic interrupt with a
`shutter 479 as a final safety switch to truly arming the gun
`100, a degree of structural safety and improving engagement
`of adjacent connectors is afforded by use of shock absorbing
`features. Specifically, a shock absorbing mount 400 or con-
`nector is shown that may be affixed into position within the
`loading tube 115. A coupling 440 may be provided for
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 009
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 009
`
`

`

`US 2016/0084048 A1
`
`Mar. 24, 2016
`
`securely receiving the module 125 as it is inserted within the
`tube 115 and mated thereto. In one embodiment, the spring
`450 includes a chamfered engagement member (e.g., a post
`that may be inserted into an aperture) such that it may also be
`of enhanced durability during connecting of the module 125
`to the mount 400.
`
`[0040] As indicated above, the mount 400 is shock absorb-
`ing. Specifically, a spring 450 is provided that allows for some
`degree of stable movement of the mount 400 as the module
`125 is forcibly pushed into place. Similarly, allowing this type
`of movement also helps to prevent disconnect of the module
`125 during transport and other times that the gun 100 may be
`prone to abrupt movement. Indeed, to a certain degree, the
`module 125 may be less affected by perforating related shock
`during a downhole perforating application, due to the pres-
`ence of the shock absorbing mount 400. Further, another
`shock absorbing mount 401 at the other end of the loading
`tube 115 may be utilized for receiving another modular gun
`component at a coupling thereof 445. Thus, the advantages
`noted here may be available beyond the particular connection
`ofthe module 125. These advantages may also include adding
`flexibility in terms of reducing precision manufacturing
`requirements and costs due to the added structural flexibility
`in fitting adjacent components together.
`[0041]
`Some embodiments may include positioning the
`shock absorber and/or the initiator outside ofthe loading tube.
`For example, in some embodiments, the shock absorber may
`be positioned at an end of the loading tube and within a
`carrier. The initiator may then be positioned adjacent to the
`shock absorber (e.g., on the end of the shock absorber or
`beside the shock absorber). Additionally, in some embodi-
`ments, the shock absorber may be formed as an integral part
`of the initiator. That is, the shock absorber may be formed as
`part of the initiator when the initiator is created.
`[0042] Continuing with reference to the particular views of
`FIGS. 4A and 4B, additional features of the loading tube 115
`and initiator assembly module 125 are also apparent. For
`example, the module 125 may include a blast wall 475 to
`minimize damage adjacent components ofthe gun 100 which
`are further uphole thereof as a result of the perforating appli-
`cation. That is, with reference to the loading tube 115 within
`the carrier 110, explosive forces may emanate from the
`shaped charge locations 410 during perforating. However, the
`blast wall 475 may be strategically located to absorb such
`explosive forces and prevent damage to other modular com-
`ponents of the gun 100 that are further uphole (e.g. via the
`bulkhead 117 of FIG. 1A). In one embodiment, the blast wall
`475 may be sacrificial plastic. However, other types of blast
`wall construction may be utilized. In the view of FIG. 4A, an
`electrical connection 43 0 is shown that emerges from the face
`425 of the module 125 for connection to a feedthru 119 as
`detailed further below.
`
`[0043] Referring now to FIGS. 5A and 5B components of a
`modular feedthru 119 are depicted. Specifically, FIG. 5A is a
`side cross-sectional view of a feedthru 119 which serves as
`
`both a pressure barrier and electrical connector. To this end,
`the feedtru 119 also serves as a structural coupling from the
`initiator assembly module 125 through a bulkhead 117 such
`as that of FIG. 1A. FIG. 5B is a perspective view ofa barrel
`insert 500 of the feedthru for securing a connector 530. Spe-
`cifically, barrel inserts 500 may be housed within cavities 560
`of the feedthru 119 for securing the connecter 530 there-
`through. For example, the connector 530 may be of an outer
`diameter that is slightly larger than the inner diameter of the
`
`barrel insert 500. Thus, bow springs 525 that define the inner
`diameter of the barrel insert 500 may forcibly deflected out-
`wardly to a degree as the connecter 530 is tightly engaged
`thereby. Ultimately, this means that a secure ground contact is
`maintained with secure resistance to movement of the con-
`
`nector 530 is provided in either direction, for example, during
`transport or delivery of the gun 100 of FIG. 1A.
`[0044] With added reference to FIG. 4B, the connector 530
`may be secured to the electrical connection 430 ofthe initiator
`assembly module 125 and to a crossover 130 at another end
`thereof (see FIG. 1A). Thus, a body portion 580 of the
`feedthru 119 provides structural support for the electrical
`path that runs from the module 125 and through the feedthru
`119. In one embodiment, the connector 530 is largely plastic
`that is molded over a central electrical pin. Therefore, a secure
`and reliable connection is provided that is also cost-effective.
`[0045] Embodiments described hereinabove include a per-
`forating gun that may be assembled from modular compo-
`nents. At the same time, however, the overall gun is of an
`axially enhanced cohesiveness among the components so as
`to ensure reliability in delivery and use downhole. From bar-
`rel inserts at a feedthru to more centrally located rings and/or
`shock absorbing mounts, substantially enhanced axial cohe-
`siveness is provided to render a modular perforating gun
`practical in terms of both cost and reliability. More specifi-
`cally, an initiator assembly module is utilized that may be
`disposed at least partially within a loading tube that is itself
`within a carrier. However, as a matter of ensuring cohesive-
`ness, centralizing rings may be disposed at the interface ofthe
`loading tube and carrier and the initiator module may incor-
`porate a detonator and avoid use of excessive external wiring.
`Similarly, a feedthru with barrel inserts may be utilized along
`with other cohesively enhancing features. This type of gun
`allows for avoidance of large open ports for sake of time
`consuming, manual wiring while exposed to the hazards and
`contaminants of the oilfield and natural human error. At the
`
`same time, this gun type is also rendered practical by the use
`of cohesively enhancing features as described.
`[0046] The preceding description has been presented with
`reference to presently preferred embodiments. Persons
`skilled in the art and technology to which these embodiments
`pertain will appreciate that alterations and changes in the
`described structures and methods of operation may be prac-
`ticed without meaningfully departing from the principle, and
`scope of these embodiments. Furthermore, the foregoing
`description should not be read as pertaining only to the pre-
`cise structures described and shown in the accompanying
`drawings, but rather should be read as consistent with and as
`support for the following claims, which are to have their
`fullest and fairest scope.
`We claim:
`
`1. A modular perforating gun forperforating a formation in
`a well at an oilfield, the gun comprising:
`a tubular carrier;
`a loading tube within the carrier to accommodate shaped
`charges;
`at least one centralizing member within the tubular carrier
`for providing a secure interface between the tubular
`carrier and the loading tube; and
`an initiator assembly module located at least partially
`within the loading tube to trigger the charges for the
`perforating.
`2. The modular perforating gun of claim 1 further compris-
`ing a modular feedthru for a bulkhead having at least one
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 010
`
`Hunting Titan, Inc.
`Ex. 1012
`Pg. 010
`
`

`

`US 2016/0084048 A1
`
`Mar. 24, 2016
`
`barrel insert within a cavity thereof for securing an electrical
`connector coupled to the initiator assembly module, the pro-
`viding ofthe secure interface and the securing ofthe electrical
`connector to enhance axial cohesiveness of the modular gun.
`3. The modular perforating gun of claim 1 wherein the
`centralizing member comprises a ring that is chamfered to
`promote a secure fit of the loading tube within the carrier.
`4. The modular perforating gun of claim 1 wherein the
`centralizing member is configured to dampen Vibrations
`through the gun.
`5. The modular perforating gun of claim 1 wherein the
`initiator assembly module comprises a blast wall for shield-
`ing the bulkhead from the shaped charges.
`6. The modular perforating gun of claim 1 wherein the
`barrel insert comprises deflectable bow springs defining an
`inner diameter thereof.
`
`7. The modular perforating gun of claim 1 further compris-
`ing a shock absorbing mount secured to the loading tube for
`receiving the initiator assembly module therein and further
`enhancing axial cohesiveness of the modular gun.
`8. The modular perforating gun of claim 1 further compris-
`ing a shock absorbing mount secured to the loading tube and
`integral to the initiator assembly module.
`9. The modular perforating gun of claim 1 wherein the
`initiator assembly module comprises a detonator of enhanced
`security thereto by a snap-fit retention clip.
`10. A modular perforating gun comprising:
`a tubular carrier;
`a loading tube within the carrier;
`a shock abs