Patent Application
20240229618
The present disclosure relates generally to oilfield technology. More specifically, the present disclosure relates to techniques for perforating downhole.
Wells are drilled into subsurface formations to reach subsurface targets, such as valuable hydrocarbons. Drilling equipment is positioned at the surface and drilling tools are advanced into the subsurface formation to form wellbores. Once drilled, casing may be inserted into the wellbore and cemented into place to complete the well. Once the well is completed, production tubing may be deployed through the casing and into the wellbore to produce fluid to the surface for capture.
Stimulation techniques have been developed to facilitate the production of fluid from the subterranean formation and into the wellbore. For example, some stimulation tools may be used for injecting and/or pumping fracturing fluids into the subterranean formation to form and/or expand fractures therethrough. Examples of injection tools are provided in U.S. Pat. No. 9,719,339, the entire contents of which is hereby incorporated by reference herein to the extent not inconsistent with the present disclosure.
In some cases, perforations may be formed along the wall of the wellbore and/or casing for passing the fracturing fluids therethrough. Some stimulation tools may be deployed into the wellbore to create perforations along a wall of the wellbore and into the subterranean formation. Examples of such tools are provided in Patent/Application Nos. EP0601880 and U.S. Pat. Nos. 5,347,929; 5,042,594; 5,088,413; 9,605,937; 6,752,083; 6,752,083; 7,565,930; 7,810,569; U.S. Ser. No. 10/760,384; U.S. Ser. No. 11/073,005; US20060070739; and US20170314373, the entire contents of which are hereby incorporated by reference herein. The perforations may be created by firing charges from the stimulation tool into the wall of the wellbore. See, for example, Patent/Application Nos. U.S. Pat. Nos. 3,713,393; 5,509,356; 9,145,769; US20080264289; US20100258292; US20120199352; US20170211363; US20170275976; US20170089678; and US20180216445, the entire contents of which are hereby incorporated by reference herein.
Despite the advancements in perforation and stimulation technology, there remains a need for techniques for more efficient and effective perforating. The present disclosure is directed at providing such needs.
In at least one aspect, the present disclosure relates to a charge assembly of a downhole perforating tool positionable in a wellbore penetrating a subterranean formation. The charge assembly comprises a charge tube, shaped charges, and propellant charges. The charge tube is positionable in a downhole perforating tool. The shaped charges and the propellant charges are receivably supported in the charge tube. Each of the shaped charges comprises a charge jacket and a charge material positioned in the charge jacket. The charge material has a detonation rate of greater than one microsecond. Each of the propellant charges comprises a propellant jacket and a propellant material positioned in the propellant jacket. The propellant charges have a detonation rate of less than one microsecond. An uphole portion of the propellant charges are positioned uphole from the shaped charges and a downhole portion of the propellant charges are positioned downhole from the shaped charges. The shaped charges are positioned between the uphole and the downhole portion. The shaped and the propellant charges are electrically connectable to a detonator for activation thereby.
In another aspect, the disclosure relates to a downhole perforating tool for perforating a wellbore penetrating a subterranean formation. The downhole perforating tool comprises charge assembly, and a detonator assembly. The charge assembly comprises a charge tube, shaped charges, and propellant charges. The charge tube is positionable in a downhole perforating tool. The shaped charges and the propellant charges are receivably supported in the charge tube. Each of the shaped charges comprises a charge jacket and a charge material positioned in the charge jacket. The charge material has a detonation rate of greater than one microsecond. Each of the propellant charges comprises a propellant jacket and a propellant material positioned in the propellant jacket. The propellant charges have a detonation rate of less than one microsecond. An uphole portion of the propellant charges are positioned uphole from the shaped charges and a downhole portion of the propellant charges are positioned downhole from the shaped charges. The shaped charges are positioned between the uphole and the downhole portion. The shaped and the propellant charges are electrically connectable to a detonator for activation thereby. The detonator assembly comprising a detonator housing positionable in the downhole perforating tool. The detonator is positioned in the detonator housing.
In yet another aspect, the disclosure relates to a method of perforating a wellbore. The method comprises positioning a downhole perforating tool with a charge assembly as in claim 1 in the wellbore; forming perforations by detonating the shaped charges; and forming fractures along the perforations by detonating the propellant charges.
Finally, in yet another aspect, the disclosure relates to a method of assembling a perforating tool. The method comprises providing shaped charges, propellant charges, a charge tube, and a detonator; assembling a charge assembly; inserting the charge assembly into a perforating housing; and operatively connecting the charge assembly to the detonator. The charge assembly is assembled by receivably positioning the shaped charges in the charge tube; receivably positioning an uphole portion of the propellant charges in the charge tube a distance uphole from the shaped charges; and receivably positioning a downhole portion of the propellant charges in the charge tube a distance downhole from the shaped charges;
In at least one aspect, the present disclosure relates to a detonation assembly for a perforating unit of a downhole tool positionable in a wellbore penetrating a subterranean formation. The perforating unit comprises an outer housing connectable to the downhole tool. The detonation assembly comprises a detonator assembly and a charge assembly. The detonator assembly is positioned in the outer housing. The detonator assembly comprises a bulkhead connected to the outer housing; a charge connector connected to the bulkhead, the charge connection having a connection end; a detonator carried by the charge connector; and a trigger coupled to the detonator and to a remote actuator. The charge assembly is insertable into the outer housing. The charge assembly comprises a charge tube to support shaped charges therein; a charge feedthru at one end of the charge tube; and a receiver at an opposite end of the charge tube, the receiver having a receptacle shaped to matingly receive the connection end of the charge connector and to engage the trigger whereby, upon insertion of the charge assembly into the outer housing, the receiver is oriented and communicatively secured to the detonator assembly.
In another aspect, the disclosure relates to a perforating unit of a downhole tool positionable in a wellbore penetrating a subterranean formation. The perforating unit comprises an outer housing and a detonation assembly. The detonation assembly is positionable in the outer housing. The detonation assembly comprises a detonator assembly and a charge assembly. The detonator assembly is positioned in the outer housing. The detonator assembly comprises a bulkhead connected to the outer housing; a charge connector connected to the bulkhead, the charge connection having a connection end; a detonator carried by the charge connector; and a trigger coupled to the detonator and to a remote actuator. The charge assembly is insertable into the outer housing. The charge assembly comprises a charge tube to support shaped charges therein; a charge feedthru at one end of the charge tube; and a receiver at an opposite end of the charge tube. The receiver has a receptacle shaped to matingly receive the connection end of the charge connector and to engage the trigger whereby, upon insertion of the charge assembly into the outer housing, the receiver is oriented and communicatively secured to the detonator assembly.
Finally, in another aspect, the disclosure relates to a method of assembling a downhole perforating tool. The method comprises assembling the detonation assembly, connecting the outer housing to the downhole tool, and establishing a communication link between the detonator and a surface receiver. The detonation assembly may be assembled by: connecting the bulkhead of the detonator assembly to the outer housing; and connecting the detonator assembly to the charge assembly by inserting the charge assembly in the outer housing while receiving the connection end of the charge connector into the receiver.
In at least one aspect, the present disclosure relates to a detonator assembly for a perforating unit of a downhole tool positionable in a wellbore penetrating a subterranean formation. The detonator assembly comprises a detonator housing positionable in the perforating unit; a first and second connectors positioned at each end of the detonator housing, the second connector positionable adjacent a charge assembly; a detonator positioned in the detonation housing; and a trigger positioned in the detonator housing. The trigger comprises a detonation switch and a detonator contact. The detonation switch is communicatively coupled between a remote actuator and the detonator contact. The detonator contact is positionable in the second connection, and has spring-loaded arms extending through openings in the second connection to urge electrical contact with the charge assembly whereby an electrical connection is maintained between the detonator and the charge assembly.
The first connector is connectable to another perforating unit of the downhole tool. The first connector comprises a bulkhead and a feedthru. The first connector is electrically connected to the detonation switch. The bulkhead is electrically connected to the detonator switch by a spring-loaded pin. The bulkhead is electrically connectable to the feedthru and the feedthru is electrically connectable to another perforating unit of the downhole tool. The second connector comprises an insert portion insertable into an opening of the detonation housing and an offset portion extending from the insert portion receivably positionable into a mated receptacle in a charge assembly of the perforating unit.
The openings in the second connector are positioned along a flat surface of the offset portion. The flat surface is positionable against a corresponding flat surface of the mated receptacle of the charge assembly. The detonator contact comprises a spring portion and a support portion, the support portion having a curved portion shaped to receive the detonator and a flat portion extending therefrom, the spring portion having spring-loaded arms in the flat portion thereof. The spring-loaded arms have an engagement portion coupled to the flat portion and engageable with a charge assembly of the perforating unit and a tip extending from the engagement portion for connection to the detonation switch. The trigger further comprises a plug and switch contacts. The first connector comprises a bulkhead and a feedthru.
In another aspect, the disclosure relates to a downhole tool positionable in a wellbore penetrating a subterranean formation. The downhole tool comprises a tool housing positionable in the wellbore and at least one perforating unit positionable in the tool housing. Each of the perforating units comprises a perforating housing; a charge assembly positioned in the perforating housing; and a detonator assembly positioned in the perforating housing. The charge assembling has a charge chamber with shaped charges releasably supported therein. The detonator assembly comprises a detonator housing positionable in the perforating unit; a first and second connectors positioned at each end of the detonator housing, the second connector positionable adjacent a charge assembly; a detonator positioned in the detonation housing; and a trigger positioned in the detonator housing. The trigger comprises a detonation switch and a detonator contact. The detonation switch is communicatively coupled between a remote actuator and the detonator contact. The detonator contact is positionable in the second connection, and has spring-loaded arms extending through openings in the second connection to urge electrical contact with the charge assembly whereby an electrical connection is maintained between the detonator and the charge assembly.
The charge assembly comprises a charge tube, a receiver, and a charge feedthru. The charge feedthru is electrically connectable with the detonator assembly. The charge feedthru comprising a locking cap, plunger, retainer, and end plate. The detonator contact has an asymmetric end positionable in the receiver. The receiver comprises a detonation link defining a detonator receptacle in the receiver. The detonator receptacle shaped to matingly receive (i.e., mate with) the asymmetric end and the detonation link having a contact surface engageable with the electrical contacts. The downhole tool further comprises a retainer, a support sub, and/or a conveyance connector.
Finally, in another aspect, the disclosure relates to a method of assembling a downhole tool. The method comprises assembling a detonator assembly; assembling a charge assembly; providing a tool housing; positioning the charge assembly in the tool housing; positioning the detonator assembly in the tool housing; and electrically connecting the detonator assembly with the charge assembly.
In another aspect, the detonator assembly is for a perforating unit of a downhole tool positionable in a wellbore penetrating a subterranean formation, and the perforating unit also including a charge assembly. The detonator assembly comprises a detonator housing positionable within the perforating unit, the detonator housing having an uphole end and a downhole end; an uphole connection and a downhole connection positioned at the uphole end and the downhole end, respectively, of the detonator housing, the downhole connection positionable adjacent the charge assembly; a detonator positioned in the detonator housing; and a trigger positioned in the detonator housing. The trigger comprises a detonation switch and a detonator contact, the detonation switch communicatively coupled, when in use, between a remote actuator and the detonator contact, the detonator contact is positionable in the downhole connection, and has spring-loaded arms extending through openings in the downhole connection to urge electrical contact with the charge assembly whereby an electrical connection is maintained between the detonator and the charge assembly.
The uphole connector is connectable to a second perforating unit of the downhole tool, the uphole connector comprises a bulkhead and a feedthru, and the uphole connector is electrically connected to the detonation switch. The bulkhead is electrically connected to the detonator switch by a spring-loaded pin. The bulkhead is electrically connectable to the feedthru and the feedthru is electrically connectable to a third perforating unit of the downhole tool. The downhole connection comprises an insert portion insertable into an opening of the detonation housing and an asymmetrical portion extending from the insert portion, the asymmetrical portion receivably positionable into a mated receptacle in the charge assembly. The openings are positioned along a flat surface of the asymmetrical portion, the flat surface positionable against a corresponding flat surface of the mated receptacle of the charge assembly. The detonator contact comprises a spring portion and a support portion, the spring and support portions each having a curved portion shaped to receive the detonator and a flat portion extending therefrom, the spring portion having the spring-loaded arms in the flat portion thereof. The flat portions of each of the spring and support portions are positionable adjacent to each other, the spring-loaded arms having an engagement portion coupled to the flat portion and engageable with the flat surface of the charge assembly and a support tip extending from the engagement portion for engagement with the flat portion of the support portion whereby the engagement portion is urged against the flat surface of the charge assembly. The trigger further comprises a plug and contacts electrically connectable between the detonator switch and the detonator contact. The uphole connector comprises a bulkhead and a feedthru, the bulkhead having a slotted lock, the feedthru having a mated pin engageable with the slotted lock.
In another aspect, the disclosure relates to a downhole tool positionable in a wellbore penetrating a subterranean formation. The downhole tool comprises a tool housing positionable in the wellbore; and at least one perforating unit positionable in the housing. Each of the at least one perforating units comprises a perforating housing; a charge assembly positioned in the perforating housing, the charge assembly having a charge chamber with shaped charges releasably supported in the charge chamber; and a detonator assembly positioned in the perforating housing. The detonator assembly comprises a detonator housing having an uphole end and a downhole end and positionable in the perforating housing; an uphole connection and a downhole connection positioned at the uphole end and the downhole end, respectively, of the detonator housing, the downhole connection positionable adjacent the charge assembly; a detonator positioned in the detonator housing; and a trigger positioned in the detonator housing. The trigger comprises a detonation switch and a detonator contact, the detonation switch communicatively coupled, when in use, between a remote actuator and the detonator contact. The detonator contact is positionable in the downhole connection, and has spring-loaded arms extending through openings in the downhole connection to urge electrical contact with the charge assembly whereby an electrical connection is maintained between the detonator and the charge assembly.
The charge assembly comprises a charge tube, a receiver, and a charge feedthru. The charge feedthru is electrically connectable with the detonator feedthru, the charge feedthru comprising a locking cap, plunger, retainer, and end plate. The detonator contact has an asymmetric end positionable in the receiver, the receiver comprising a detonation link defining a detonator receptacle in the receiver, the detonator receptacle shaped to matingly receive the asymmetric end and the detonation link having a contact surface engageable with the electrical contacts. The downhole tool further comprises a retainer, a support sub, and/or a conveyance connector.
Finally, in another aspect, the disclosure relates to a method of assembling a downhole tool. The method comprises assembling a detonator assembly; assembling a charge assembly; providing a tool housing; positioning the charge assembly in the tool housing; positioning the detonator assembly in the tool housing; and electrically connecting the detonator assembly with the charge assembly.
The method further comprises positioning a second perforating unit in the tool housing and connecting the uphole connector to the second perforating unit. The uphole connector comprises a bulkhead and a feedthru, and the method further comprises electrically connecting the uphole connector to the detonation switch.
This Summary is not intended to be limiting and should be read in light of the entire disclosure including text, claims and figures herein.
So that the above recited features and advantages of the present disclosure can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. The appended drawings illustrate example embodiments and are, therefore, not to be considered limiting of its scope. The figures are not necessarily to scale and certain features, and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
The description that follows includes exemplary apparatus, methods, techniques, and/or instruction sequences that embody techniques of the present subject matter. However, it is understood that the described embodiments may be practiced without these specific details.
This disclosure relates to a denotation assembly of a downhole perforating tool positionable in a wellbore at a wellsite. The perforating tool is provided with one or more perforating units, each perforating unit including an outer housing and a detonation assembly. The detonation assembly includes a charge assembly and a detonator assembly secured in the outer housing. The perforating units have quick-locking features to facilitate assembly and operation of the perforating tool and its detonator.
The charge and detonator assemblies are provided with quick-locking features for quick, one-way, redundant, and secure assembly and operation. For example, the charge and detonator assemblies may have one-way pin and guide (e.g., slot) locking mechanisms (with or without additional locks) for securing the components in place. In another example, the charge and detonator assemblies may have components shaped for one-way insertion into and/or connection with adjacent components to assure proper positioning and fit of the components.
In yet another example, the charge and detonator assemblies may have locking contacts with push-in place dual spring activation and redundant contact surfaces for maintaining a communication connection with the detonator and/or between the detonator assembly and the charge assembly for the passage of signals therebetween. The communication links and/or connections may be or include various communication components, such as wires, cables, plates, contacts, switches, plugs, and/or other features, capable of passing electrical, power, and/or other signals.
The present disclosure seeks to provide features capable of providing one or more of the following, among others: means for signal communication (e.g., electrical connection), push in place assembly, spring loaded contact, redundant components and/or contacts, mechanisms to assure good electrical contact, reliable communication and/or operation, pre-assembly and/or offsite assembly capabilities, snap on electrical connections, quick connections and/or locks, no requirement for soldering and/or crimping contacts, reliability, time savings, low maintenance costs, etc.
The wellsite 100 may be any wellsite positioned about a subterranean formation, such as an unconventional formation (e.g., shale) with a reservoir (e.g., oil, gas, water) therein. The surface equipment 102a includes a crane 106, a truck 108, a wellhead assembly 110, and a surface unit 111. The crane 106 supports a pulley 112. The truck 108 supports a spool 114. A conveyance (e.g., wireline) 116 extends from the spool 114 over the pulley 112 and into the wellbore 104. The surface unit 111 is coupled to the conveyance 116 for communication therewith.
The wellhead assembly 110 is disposed at a surface opening of the wellbore 104. An example wellhead assembly 110 is shown in
The wireline lubricator 220a is positioned at an upper end of the wellhead assembly 110 and is receivably supported in the hydraulic disconnect 220b. Seals 222 are positioned at an upper end of the wireline lubricator 220a for fluid isolation within the wellhead assembly 110. The wireline lubricator 220a may be detached from the wellhead assembly 110 and carried by the crane 106 for placement in the hydraulic disconnect 220b.
The hydraulic disconnect 220b includes a tulip 226 at an upper end to receive the wireline lubricator 220a. The hydraulic disconnect 220b is supported between the wireline lubricator 220a and the frac tree 220c. Once the wireline lubricator 220a is positioned in the tulip 226, the valves 119b on the hydraulic disconnect 220b may be opened to pass fluid therethrough or closed to isolate the passage therein. A lower end of hydraulic disconnect 220b is connectable to an upper end of the frac tree 220c. The frac tree 220c includes a goat head 228a and a cross member 228b. A lower end of the frac tree 220c is connectable to the wellhead 220d.
Referring back to
The downhole tool 118 may be a downhole perforating tool or other downhole tool disposable in the wellbore 104 capable of carrying a perforating unit 132 for perforating the wellbore 104 as is described further herein.
The perforating units 132 are positioned in the housing 130 and carry the detonation assembly 133. The detonation assembly 133 carries shaped charges 136. The shaped charges 136 are explosive components that form a focused radially-oriented jet when activated. This jet makes a perforation 135 that extends through the wall of the wellbore 104 (and the casing 117 and cement if present) and into the subterranean formation surrounding the wellbore 104. The shaped charges 136 may be configured to create the perforations 135 for passage of fracturing (or injection) fluid into the formation for hydraulic fracturing therein.
The perforating units 132 may be communicatively connected to the surface unit 111 by the wireline 116 and/or by other means (e.g., wireline, electromagnetic, sonar, or other communication means). The perforating units 132 may be independently operated, or communicatively linked together for integrated operation therebetween. A communication link (e.g., wire or cable, not separately shown) may extend from the wireline 116 through the housing 130 and/or the perforating units 132. The perforating units 132 may be connected by the communication link for communication therebetween and/or for communication with the other components of the downhole tool 118.
The downhole tool 118 may be provided with various components, such as a conveyance connector 133a, a collar locator (“CCL”) 133b, and a plug-setting tool 133c, all shown in
The downhole tool 118 and/or one or more of the perforating units 132 may be coupled via a wired or wireless connection to the surface unit 111 as described above for operation therewith. The perforating unit(s) 132 may be activated by the surface unit 111 to selectively fire one or more of the shaped charges 136 to form the perforations 135 as schematically depicted in
During operation, the downhole tool 118 may be carried in the wireline lubricator 220a via the wireline 116 to the wellsite 100 with the crane 106. Once the wireline lubricator 220a is secured in the tulip 226, the valve 119b of the hydraulic disconnect 220b may be opened to pump fluid to push the downhole tool 118 through the wellhead assembly 110 and into the wellbore 104. Fluid beneath the downhole tool 118 may be pumped back to the surface or exited out the wellbore 104 via pre-existing perforations (not shown) in the casing 117 to avoid the need for the fluid to return to the surface.
The CCL 133b may communicate an electrical signal up the wireline 116 to the surface unit 111 as it passes between adjacent segments of the casing 117. A position of the downhole tool 118 may be determined by counting these signals as the perforating system is pumped down the wellbore and by knowing the length of each segment of casing 117. However, other embodiments may use other techniques for determining the location of the CCL 133b in the wellbore 104.
When the bottom (i.e., downhole end) of the downhole tool 118 is at a desired position above the perforations 135 that are closest to the surface, pumping may be terminated. A coded communication signal may be sent down the wireline 116 to activate the plug-setting tool 133c to lock the downhole tool 118 in position. The signal may also be used to activate a switch in the perforating unit 132 to activate the perforating unit 132 to fire as is described further herein. Once fired, the plug-setting tool 133c may be activated to disconnect the downhole tool 118 and move the downhole tool 118 to another location, or out of the wellbore 104.
The perforating housing 436a includes an outer tube 438a, a support sub 438b, and a retainer 438c. The outer tube 438a is a tubular member slidingly receivable in the housing 130 (shown in
The support sub 438b is a tubular member shaped to support the retainer 438c and the detonator assembly 436b. The retainer 438c is positioned in an end of the support sub 438b to secure the detonator assembly 436b in the perforating housing 436a. The detonator assembly 436b is positioned in the support sub 438b and extends from the retainer 438c a distance into the charge assembly 436c for operative connection therewith as is described further herein.
Each of the perforating units 132 is provided with a communication link (e.g., wire) 441 extending therethrough for activating the detonator assembly 436b to fire the shaped charges 136. The communication link 441 may be a wire extending from the detonator assembly 436b through the charge tube 440a and to the charge feedthru 440c. The perforating units 132, where multiple perforating units 132 are employed, are connected in series with the communication link 441 coupled therebetween for selective activation of one or more of the perforating units 132. The communication link 441 of each perforating unit 132 may be coupled to an adjacent perforating unit 132 at each end of the perforation unit via the detonator assembly 436b at one end and the charge feedthru 440c at the other end for communication therewith. This connection may be repeated between the perforating units 132 to provide a series of connections for communication across the perforating units 132.
Referring to
The charge assembly 436c includes a charge tube 440a, a receiver 440b at one end of the charge tube 440a, and the charge feedthru 440c at an opposite end of the charge tube 440a. The charge tube 440a is slidingly receivable in the outer tube 438a. The charge tube 440a has the shaped charges 136 supported therein. The charge tube 440a also has a charge cable 442a and ports 442b.
The receiver 440b may be a flange shaped member receivable about an end of the charge tube 440a for connection to the support sub 438b. The receiver 440b may also be provided with a charge receptacle 444 shaped to receive the end of the detonator assembly 436b for connection therewith. The charge cable (or detonator cord) 442a is a fuse connected to the receiver 440b. The charge cable 442a extends from the receptacle 444 through the charge tube 440a and along a periphery of the charge tube 440a in a spiral configuration.
The charge cable 442a is connected to each of the shaped charges 136 in the charge tube 440a for activation thereof. The ports 442b extend through the charge tube 440a. The shaped charges 136 are positioned about the ports 442b to fire jets therethrough upon detonation. The ports 442b may be alignable with openings 443 in the perforating housing 436a for firing therethrough upon detonation.
The charge feedthru 440c is positionable at an opposite end of the charge tube 440a from the receiver 440b. As shown in greater detail in
As shown in
When inserted into the end of the charge tube 440a, the key 448a of the receiver 440b is slidingly receivable into the guide slot 446a. The receiver 440b may be rotated so that the key 448a passes into the guide slot 446a, thereby positioning the receiver 440b in the desired position while also preventing unintentional retraction of the receiver 440b out of the charge tube 440a.
The charge tube 440a may also be provided with a locking tabs 451a and fastener holes 451b to secure the receiver 440b and feedthru 440c in position. The locking tabs 451a may be a cutout portion of the charge tube 440a corresponding to tab cavity 450a in the receiver 440b and the feedthru 440c. When the receiver 440b/the feedthru 440c are in position, the corresponding locking tab 451a may be pressed into the tab cavity 450a thereby further preventing movement of the receiver 440b/feedthru tube 440c about the charge tube 440a. Fasteners (not shown), such as pins, screws, bolts, etc., may be passed through fastener hole 451b and into a mated hole 450b in the receiver 440b/feedthru tube 440c to secure the receiver 440b/feedthru 440c to the charge tube 440a.
As also shown in
As shown in these views, the detonator assembly 436b is insertable into the support sub 438b and into the end of the charge assembly 436c. The receptacle 444 of the receiver may be an offset (e.g., hemispherical) insert placed along an inner surface of the receiver 440b with features corresponding with the end of the detonator assembly 436b. The receptacle 444 may have, for example, a shape, surfaces, contacts, etc., for receivingly engaging the detonator assembly 436b to provide a secure fit for contact and communication therebetween as is described further herein.
As shown in these views, the detonator assembly 436b includes a detonator housing 752a, a detonator 752b, and a switch assembly (or trigger) 752d. The detonator assembly 436b also includes a tube portions 754a, a bulkhead 754b, a second connector 754c, and a detonator feedthru 754d. The detonator housing 752a is slidably positionable in the support sub 438b. The detonator housing 752a may include one or more tube portions 754a connectable to form an enclosed chamber 759. The bulkhead 754b and the second connector 754c are positioned at opposite ends of the detonator housing 752a to close each end thereof.
The bulkhead 754b is positionable between the detonator housing 752a and the retainer 438c. A portion of the bulkhead 754b is insertable into and threadedly connected to an end of the detonator housing 752a. Another portion of the bulkhead 754b extends from the detonator housing 752a and is insertable into and threadedly connectable to the retainer 438c. The bulkhead 754b has a passage to receive the detonator feedthru 754d therethrough. The bulkhead 754b supports the detonator feedthru 754d about the end of the detonator assembly 436b to form a first connector for connection to the charge assembly 436c of an adjacent perforating unit 132.
The detonator feedthru 754d is connected by the switch assembly 752d to the detonator 752b. The switch assembly 752d includes a switch 753a, a plug 753b, and contact 753c1. The switch assembly 752d also includes connectors 755a1-a5 and cables 755b. The plug 753b is seated in the switch 753a. The connectors 755a1-a4 are connected to the switch plug 753b via cables 755b. The connectors 755a1-a3 are also connected to the detonator feedthru 754d, bulkhead 754b, contact 753c1, respectively. The connector 755a4 is also connected the switch plug 753b to the detonator 752b. The connectors 755a1-a4 may take various forms. In the examples shown, the connectors 755a1-a3 include a pin contact 755a1, a spring coupling 755a2, and a slotted receptacle 755a3 capable of mating with the components and connectable with the cables 755b for communication therebetween. The cables 755b are provided with connectors 755a5 for insertion into the switch plug 753b.
As shown in
The cylindrical portion 756a is shaped to close an end of the detonator housing 752a. The hemispherical portion 756b is insertable through the support sub 438b and into the receiver 440b. The hemispherical portion 756b is shaped to matingly engage the contact receiver positioned in the charge tube 440a. The hemispherical portion 756b is also shaped for a one way fit into the charge tube 440a for positive alignment therein. The hemispherical portion 756b is also provided with a contact surface 757a positionable against a corresponding contact surface 757b of the receptacle 444.
The contacts 753c1, c2 are shown in greater detail in
Each of the arms 762a have elongate cutout portions that are curved about the flat portion. The cutout portions include a curved portion 764a and tip portions 764b. The curved portions 764a are attached at one end from the flat portion and extend therefrom to rise a distance above the flat portion. The tip portions 764b extend from the curved portions through an opening defined by cutout of the arms 762a, and to a distance below the flat portion.
The contacts 753c1, c2 may be of a conductive material (e.g., metal). The arms 762a may be compressible against the arms 762b of the adjacent support arms 762b. When the curved arms 762a are compressed against the arms 762b, the curved arms 762a have a spring force that extends therefrom. The curved arms 762a are shaped to extend through openings 761 in the second connector 754c.
The detonator contact 753c1 is connected at one end to the switch assembly 752d and has another end extended into the second connector 754c. The detonator 752b is supported in the housing between the switch assembly 752d and the second connector 754c. The detonator 752b is supported in the housing 752a by the contact 753c1. The curved support portion 760b is shaped to receive an outer surface of the detonator 752b.
As shown in
When the second connector 754c is inserted into the receptacle 444 of the charge assembly 436c, the contact surface 757a of the second connector 754c is positioned adjacent the corresponding contact surface 757b of the receptacle 444. The curved arms 762a of the detonator contact 753c1 extends through the openings 761 for engagement with the charge receptacle 444. The spring force of the curved arms 762a urges the detonator contact 753c1 into communicative contact with the contact 753c2. The spring force may be defined to apply sufficient force to urge contact via the switch assembly 752d (
In operation, a signal is sent from the surface unit 111 (shown in
The signal passes through the detonator feedthru 754d and the bulkhead 754b, and to the switch assembly 752d (shown in
The perforating units 1632 of
Referring collectively to
The outer housing 1630 is a tubular member shaped to receive the integrated detonation assembly 1633 therein. The outer housing 1630 may be provided with connection means (e.g., internal threads) for connection of the outer housing 1630, and to a portion of an adjacent perforating unit 1632. While not shown in this version, additional housings may optionally be provided, such as the outer housing 130 and the outer tube 438a of
The charge assembly 1636c is shown in greater detail in
The charge tube 1640a may be similar to the charge tube 440a of
The receiver 1640b and the charge feedthru 1640c are insertable into and connected to opposite ends of the charge tube 1640a. One of the rings 1641 is positioned between the charge tube 1640a and the receiver 1640b, and the other ring 1641 is positioned between the charge tube 1640a and the receiver 1640b. The rings 1641 are supported about the charge tube 1640a adjacent to the receiver 1640b and the feedthru 1640c, and are shaped for sliding insertion into the outer housing 1630 as shown in
As shown in
The charge tube 1640a also has a charge cable 1642a for communication with the shaped charges 136. The charge cable (or detonator cord) 1642a may act as a fuse connected to the receiver 1640b. The charge cable 1642a extends from the receiver 1640b through the charge tube 1640a and along an outer surface of the charge tube 1640a. The charge cable 1642a is connected to each of the shaped charges 136 in the charge tube 440a for activation thereof. The charge tube 1640a is supported within the outer housing 1630 between the two rings (end caps) 1641. The charge tube 1640a may be manufactured with clips (not shown) to support the charge cable 1642a (and wire 441 of
The receiver 1640b may have features similar to those of receiver 440b of
The charge feedthru 1640c may be similar to the charge feedthru described in
When connected in series, multiple ones of the integrated detonation assemblies 1633 may be communicatively connected to pass signals therethrough for activation of the detonation assembly 1633 to set off the shaped charges 136 as is described further herein. A communication link (e.g., wire 441 of
Referring collectively to
As shown in these views, the detonator assembly 1636b includes a detonator housing 2154a, a bulkhead 2154b, a charge (second) connector 2154c, a detonator 2152b, a switch assembly (or trigger) 2152d, and a detonator feedthru 2154d. The detonator assembly 1636b may be assembled and oriented azimuthally to minimize mechanical shock during the electrical connection therebetween.
The bulkhead 2154b is at a charge end 1637b of the detonator housing 2152a and the charge connector 2154c is at the connection end 1637a of the detonator housing 2152a with the detonator housing 2152a therebetween. The detonator feedthru 2154d is supported in the bulkhead 2154b and the detonator 2152b is supported in the charge connector 2154c with the switch assembly 2152d connected therebetween. The bulkhead 2154b acts as a dual contact electrical connector on one side with the centralized detonator feedthru 2154d (which acts as an electrical pin) on the other. The bulkhead 2154b isolates the gun from pressure created when a shaped charge 136 in a perforating unit 1632 is fired, and maintains contact via the detonator feedthru 2154d.
The connection end 1637a of the charge connector 2154c is insertable into the outer housing 1630 and into the receiver 1640b positioned therein (see, e.g.,
The detonator feedthru 2154d is connected by the switch assembly 2152d to the detonator 2152b. The switch assembly 2152d includes a switch 2253a, plugs 2253b1, b2, and contact 2253c. The plugs 2253b1,b2 are seated in the switch 2253a. The detonator 2152b is connected to the switch 2253a by connectors (not shown) for communication thereby, which may have features similar to those of in
In operation, a signal is sent from the surface unit 111 (shown in
The signal passes through each of the perforation units 132,1632 and to the detonator assemblies 436b, 1636b of
The signal passes through the detonator feedthru 754d, 2154d and the bulkhead 754b, 2154b, and to the switch assembly 752d, 2152d (shown in
The method 2300 may involve assembling the detonation assembly by: connecting the bulkhead of the detonator assembly to the outer housing, and connecting the detonator assembly to the charge assembly by inserting the charge assembly in the outer housing while receiving the connection end of the charge connector into the receiver; and then connecting the outer housing to the downhole tool.
Part or all of the assembly may be performed on or offsite from the wellsite.
Portions of the method may be performed in various orders, and part or all may be repeated.
Hybrid Perforating Unit with Shaped Charges and Propellant Charges
This disclosure also relates to a downhole tool and/or downhole perforating unit with propellant charge(s). The downhole tool may include one or more hybrid perforating units for perforating the wellbore (see, e.g.,
The shaped charges and propellant charges may be used to facilitate the flow of fluid from the wellbore and into the formation during injection operations. The shaped charges may be fired from the charge tube and into the formation to form perforations in the wall of the wellbore, thereby creating passageways for injecting fluid to flow through the perforations and into the formation. The propellant charge(s) may be detonated to generate fracture pressure that passes from the downhole tool and into the perforations. This fracture pressure may be sufficient to create micro-fractures in the formation surrounding the perforations, thereby enhancing (e.g., increasing, extending, expanding, etc.) the perforations and further facilitating the flow of injection fluid into the formation.
The propellant charges may have the same or different configuration (e.g., shape, structure, materials, jacket, etc.) as the shaped charges depending on operational needs (e.g., placement in the charge tube, spacing, operation, simplified manufacture, retrofit to shaped charge cavities in charge tubes, etc.). The propellant charges may contain a propellant material having a high volatility (e.g., an aviation or jet fuel) having desired parameters (e.g., timing, speed, etc.) capable of generating the fracture pressure necessary to fracture the perforations.
The shaped charges and propellant charges may be positioned in the downhole tool in a manner that facilitates operations. The shaped charges may be positioned along a horizontal perforating plane, and the propellant charges may be positioned along a horizontal pressure plane that is a distance from the horizontal perforating plane. By separating the perforating plane from the pressure plane, multiple shaped charges may be placed along the same perforating plane for perforation in multiple directions, and larger volume propellant charges may be used in the pressure plane to increase the amount of fracture pressure generated. Multiple perforating and/or pressure planes may be provided within the same charge tube.
The hybrid perforating units, the shaped charges, and the propellant charges are intended to provide one or more of the following capabilities: to facilitate injection capabilities; to enhance perforating operations; to enable flexibility in selecting propellant perforation dimensions; to extend the fractures formed by the propellant perforations; to allow the use of propellant charges and shaped charges in the same charge tube, perforating unit, and/or downhole tool; to allow perforation along multiple planes and/or multiple directions; to facilitate perforating of the wellbore; to facilitate fracturing of the formation; etc.
As shown in
The perforating housing 2436a houses the detonation assembly 2433 therein. The detonation assembly 2433 includes a detonator assembly 2436b, and the hybrid charge assembly 2436c. The detonator assembly 2436b may be, for example, similar to the detonator assembly 436b described herein (see, e.g.,
In the example shown in
One or more of the hybrid and/or other perforating units as described herein may be positioned in the downhole tool 118 (
As shown in these views, the perforating housing 2536a is shaped to receive and house the hybrid perforating unit 2532. This view also shows an example of the position of the propellant charges 2436, 2536 and the shaped charges 136 within the charge tube 2540a. In this example, the propellant charges 2436, 2536 are aligned horizontally along pressure planes P1 and P3, respectively, and the shaped charges 136 are aligned horizontally along a perforating plane P2 between planes P1 and P3. Multiple (e.g., 3) shaped charges 136 are shown in perforating plane P2, with each shaped charge 136 pointed radially in a different direction as indicated by the arrows. One propellant charge is shown in each perforating plane P1, P3. In this position, the shaped charges 136 perforate in three radial directions about the wellbore from plane P2, and the propellant charges 2436 along horizontal planes P1 and P3 generate pressure uphole and downhole, respectively, from the shaped charges 136 to generate pressure in the perforations as is described further herein.
The horizontal pressure planes P2, P3 are located a distance from the perforating plane P1. The placement of the perforating plane(s) may be selected to allow multiple shaped charges 136 to be placed in the same perforating plane for perforation in multiple directions. The placement of the pressure plane(s) may be selected to increase the size of the propellant charge, thereby increasing an amount of fracture pressure generated. Various numbers of shaped charges 136, perforating planes P1, propellant charges 2436, and pressure planes P2, P3 may be provided.
As also shown in
The charge tube 2540a also has the wire 441 and the charge cable 442a as described with respect to
The charge tube 2540a has the shaped charges 136 and the propellant charges 2436 supported therein. The propellant charges 2436 may include one or more of the disk propellant charges 2436 and/or the pellet propellant charges 2536 as described in
The shaped charges 136 and the propellant charges 2436 may be positioned about ports 2642b in the charge tube 2540a. The ports 2642b may be aligned with the housing openings 2443 in the perforating housing 2436a (
As also shown by the example in
The propellant charge 2436 includes a propellant jacket (or charge case) 2760 and propellant material 2762. The propellant charge 2436 may be configured to provide sufficient force to break the formation. The propellant material 2762 may be a chemical mixture of a flammable material, such as rocket, aviation, or other fuel, ignitable by the charge cable 442a (
The propellant material 2762 used to generate the fracture pressure PFrac may be different from the charge material in the shaped charge 136 used to generate force for perforation. The propellant material 2762 may have a predefined timing and energy generated from ignition that is different from the charge material. For example, the shaped charge 136 with the charge material may detonate in micro-seconds (e.g., greater than 1 micro-second), and the propellant charge 2436 with the propellant material 2762 may detonate in milliseconds (e.g., less than one micro-second). In another example, the propellant material 2762 may be more volatile (e.g., aviation fuel) in order to generate the fracture pressure PFrac, which may be different from the explosive charge material (e.g., HMX (octogen), TNT, etc.) in the shaped charge 136 used to punch through the housing 2536a and perforate the formation. Examples of shaped charges that may be used are commercially available from WELLMATICS™ at https://www.wellmatics.com/solutions/energetics/shaped-charges.
The propellant jacket 2760 may be shaped to fit within the space provided within the selected perforating unit to facilitate operation, ignition, pressurization, manufacture, reloading, retrofitting with existing equipment, etc. For example, the propellant jacket 2760 may be provided with, for example, a shape to support a maximum volume of the propellant material 2762. An increased volume may be provided to increase burn rate, pressure, etc. In another example, the propellant jacket 2760 may be provided with a shape similar to the shape of the shaped charge 136. The same shape may enable the use of the same manufacturing equipment and/or facilitate installation and operation within the same perforating unit as the shaped charge.
The propellant jacket 2760 may be made of a plastic material, such as PEEK, or a metal, such as steel or metal alloy, that may be shaped to support the propellant material 2762 therein. The propellant jacket 2760 may be shaped to facilitate storage, detonation, firing, and/or pressure generation of the propellant material 2762. In the example shown, the propellant jacket 2760 is a cup-shaped member with a charge opening 2762a at one end and the cord clip 2658 at an opposite end. The charge opening 2762a has a circular shaped for receiving and storing the propellant material 2762 therein.
The propellant jacket 2760 has a tubular upper portion 2762b with a raised lip 2762c about the charge opening 2762a. A mid tapered portion 2762d extends from the upper portion 2762b, and a bottom tapered portion 2762e extends from the mid tapered portion 2762d toward the clip 2658. A clip receptacle 2762f extends from the bottom tapered portion 2762e and is shaped to receive the clip 2658 therein.
The clip 2658 extends from the clip receptacle 2762f. The clip 2658 may be formed as part of the propellant jacket 2760, or may be formed separately for insertion into the clip receptacle 2764f. The clip 2658 has a circular body 2764a with a pair of prongs 2764b and a plug 2764c extending therefrom. The plug 2764c is receivable in the clip receptacle 2762f. The prongs 2764b define a cable receptacle 2764d therebetween for grippingly engaging the charge cable 442a. The clip 2658 may be used to support the propellant charge 2436 in the charge tube 2540a (
The propellant charge 2436 may also be configured to generate sufficient pressure in the wellbore 104 (
The desired shape and materials used may be modeled or empirically selected to provide the optimum fracture pressure PFrac. The configuration may be selected to enable the formation to generate fractures without damaging the downhole tool 118. Parameters that may be considered for optimizing the operation and/or fracturing may include, for example, wellsite parameters (e.g., wellbore geometry, formation or rock strength, wellbore fluid, casing thickness, etc.), propellant parameters (e.g., quantity, type, volume, burn rate, etc.), shape parameters (e.g., puncture size, perforating dimensions, etc.), tool parameters (e.g., volume inside tool, position of propellant and shaped charges, etc.), etc.
The first hybrid perforating unit 2832a is shown forming shaped perforations SP in the wall of the wellbore 104 using the shaped charges 136. The shaped charges 136 may have explosives that explode upon detonation to form the shaped perforations SP. The shaped charge 136 may form a tunnel shaped perforation by piercing through the housing 2436a and the casing 117. A perforating force of, for example, about 100 psi (689.50 KPa) may be generated by the shaped charges 136. The explosion of the shaped charges 136 pass through the ports 2642b in the charge tube 2440a, and into the formation to form the shaped perforation SP in the wall of the wellbore 104. The shaped perforation SP has a length SPI and a diameter SPd. The explosive material of the shaped charge 136 explodes in a manner that generates an explosive force against the wall of the wellbore 104 as indicated by the arrows, thereby extending into the shaped perforation SP.
The propellant charge 2436 may ignite upon detonation to generate a pressure PFrac in the hybrid perforating unit 2832a. This ignition of the propellant charges 2436 passes through the hybrid perforating unit 2832a, through the ports 2642b, and out through the perforation(s) SP. During ignition, the propellant material 2762 (
As indicated by the arrows, the detonation of the propellant charge 2436 generates the fracture force PFrac along the shaped perforation SP and forms micro-fractures 2872 therein. These micro-fractures 2872 crack open (or fracture) the formation F surrounding the shaped perforation SP to further extend the perforation SP. The micro-fractures 2872 may be used to facilitate flow of an injection fluid through the shaped perforation SP and into the surrounding formation F, and/or to facilitate production of fluid from the formation F into the wellbore 104.
Referring next to the perforating unit 132 downhole from the hybrid perforating unit 2832a, this perforating unit 132 has the shaped charges 136 in a helical arrangement for forming the shaped perforations SP. The perforating unit 132 may be similar to that of
Referring next to the perforating unit 2832b downhole from the perforating unit 132, like the hybrid perforating unit 2832a, this hybrid perforating unit 2832b has the shaped charges 136 positioned in separate planes from the propellant charges 2436. The shaped charges 136 may be positioned in different horizontal planes from each other and/or from the propellant charges 2436. The shaped charges 136 may also be oriented for perforating at a desired radial angle as indicated by the arrows (e.g., at x+180), and multiple (e.g., 2) of the propellant charges 2436 may be positioned above and below the shaped charge 136. After perforation of the shaped charge 136, one or more of the propellant charges 2436 may be triggered to generate fracture pressure PFrac to fracture the perforation(s) SP.
While
In another example, a separate shape perforating unit 2832c and a separate perforating unit 2832d may optionally be provided. In this separate configuration, the shaped charges 136 and the propellant charges 2436 are positioned in separate perforating units 2832c,d as schematically indicated by the dashed line. The separate configuration may enable individual transport, replacement, configuration, and installation of the separate perforating units 2832c,d. The separated propellant perforating unit 2832c may also allow the fracture pressure PFrac to pass directly from the propellant perforating unit 2832c to the wellbore and into the perforation SP. The separated perforating units 2832c,d may also be fluidly connected to permit the fracture pressure PFrac generated by the propellant charges 2436 to pass through the perforating unit 2832d as shown by the curved arrows.
As shown in
As shown in
As shown in
The method 3000b involves 3095 positioning a downhole tool in a wellbore, the downhole tool comprising a perforating housing with a charge assembly therein. The charge assembly comprises a charge tube; a shaped charge positioned in the charge tube; and propellant charges comprising a jacket and an aviation fuel positioned in the jacket, one of the propellant charges positioned in the charge tube uphole from the shaped charge, another of the propellant charges positioned in the charge tube downhole from the shaped charge. The method 3000b continues with 3096 forming a hybrid perforation in the wall of the wellbore by detonating the shaped charges, and 3097 forming fractures along the shaped perforation by detonating the propellant charges.
Portions of the method may be performed in various orders, and part or all may be repeated.
While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible. For example, various combinations of one or more of the features and/or methods provided herein may be used.
Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter. For example, while certain connectors are provided herein, it will be appreciated that various forms of connection may be provided. While the figures herein depict a specific configuration or orientation, these may vary. First and second are not intended to limit the number or order.
Insofar as the description above and the accompanying drawings disclose any additional subject matter that is not within the scope of the claim(s) herein, the inventions are not dedicated to the public and the right to file one or more applications to claim such additional invention is reserved. Although a very narrow claim may be presented herein, it should be recognized the scope of this invention is much broader than presented by the claim(s). Broader claims may be submitted in an application that claims the benefit of priority from this application.
This application claims the benefit of U.S. Patent Application No. 63/450,963 filed on Mar. 9, 2023, the entire contents of which is hereby incorporated by reference herein. The application is also a continuation in part of U.S. Non-Provisional application Ser. No. 17/366,884 filed on Jul. 2, 2021, which is a continuation of U.S. Non-Provisional application Ser. No. 16/676,246 filed on Nov. 6, 2019, which is a continuation-in-part of U.S. Non-Provisional application Ser. No. 16/537,347 filed on Aug. 9, 2019, which claims the benefit of U.S. Provisional Application No. 62/717,320, filed on Aug. 10, 2018, the entire contents of which are hereby incorporated by reference herein. This application is also owned by the same owner of U.S. application Ser. No. 17/585,446 filed on Jan. 28, 2022 the entire contents of which are hereby incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 63450963 | Mar 2023 | US | |
| 62717320 | Aug 2018 | US | |
| 63141975 | Jan 2021 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17585446 | Jan 2022 | US |
| Child | 18600713 | US | |
| Parent | 16676246 | Nov 2019 | US |
| Child | 17366884 | US | |
| Parent | 16537347 | Aug 2019 | US |
| Child | 16676246 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17366884 | Jul 2021 | US |
| Child | 17585446 | US |
