FLUID COMMUNICATION METHOD FOR HYDRAULIC FRACTURING

TECHNICAL FIELD

The present disclosure relates generally solutions for preventing erosive enlargement of fluid communication holes in a wellbore casing and in particular, to the fitting of casing perforations with wear-resistant inserts to protect against erosion and ensure consistent perforation aperture size.

BACKGROUND

To obtain hydrocarbons such as oil and gas, wellbores are typically drilled by rotating a drill bit that is attached at the end of the drill string. Modern drilling systems frequently employ a drill string having a bottom hole assembly and a drill bit at an end thereof. The drill bit is rotated by a downhole motor of the bottom hole assembly and/or by rotating the drill string. Pressurized drilling fluid is pumped through the drill string to power the downhole motor, provide lubrication and cooling to the drill bit and other components, and carry away formation cuttings.

A large proportion of drilling activity involves directional drilling, e.g., drilling deviated, branch, and/or horizontal wellbores. In directional drilling, wellbores are usually drilled along predetermined paths in order to increase the hydrocarbon production. As the drilling of the wellbore proceeds through various formations, the downhole operating conditions may change, and the operator must react to such changes and adjust parameters to maintain the predetermined drilling path and optimize the drilling operations. The drilling operator typically adjusts the surface-controlled drilling parameters, such as the weight on bit, drilling fluid flow through the drill string, the drill string rotational speed, and the density and/or viscosity of the drilling fluid, to affect the drilling operations.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the above-recited and other advantages and features of the disclosure can be obtained, a more particular description of the principles briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only exemplary embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the principles herein are described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1A is a schematic diagram of an example drilling environment, in accordance with various aspects of the subject technology.

FIG. 1B is a schematic diagram of an example wireline logging environment, in accordance with various aspects of the subject technology.

FIG. 2 illustrates steps of an example process for constructing a wellbore casing string, according to some aspects of the disclosed technology.

FIG. 3 is a cut-away view of a casing string with multiple casing sections, according to some aspects of the disclosed technology.

FIG. 4A illustrate cut away views example inserts that contain plugs, according to some aspects of the disclosed technology.

FIG. 4B illustrates a cut away view of a wellbore including a casing section containing an insert, according to some aspects of the disclosed technology.

FIG. 5A is a cut away view of a wellbore and a casing string in which a detonating cord is configured to remove a casing plug, according to some aspects of the disclosed technology.

FIG. 5B is a cut away view of a wellbore and a casing string in which an explosive device is configured to remove a casing plug, according to some aspects of the disclosed technology.

FIG. 6A is a cut away view of a casing string in which an erosive chemical containment device is configured to remove a casing plug, according to some aspects of the disclosed technology.

FIG. 6B is a cut away view of a casing string in which multiple chemical containment devices are configured to facilitate removal of a casing plug, according to some aspects of the disclosed technology.

FIG. 7 is a schematic diagram of an example system embodiment.

DETAILED DESCRIPTION

Various embodiments of the disclosure are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without parting from the spirit and scope of the disclosure.

Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or can be learned by practice of the principles disclosed herein. The features and advantages of the disclosure can be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the disclosure will become more fully apparent from the following description and appended claims, or can be learned by the practice of the principles set forth herein.

It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features. The description is not to be considered as limiting the scope of the embodiments described herein.

Subterranean hydraulic fracturing is conducted to increase or “stimulate” production from a hydrocarbon well. To conduct a fracturing process, pressure is used to pump fracturing fluids, including some that contain propping agents (“proppants”), down-hole and into a hydrocarbon formation to split or “fracture” the rock formation along veins or planes extending from the well-bore. Once the desired fracture is formed, the fluid flow is reversed and the liquid portion of the fracturing fluid is removed. The proppants are intentionally left behind to stop the fracture from closing onto itself due to stresses within the formation. The proppants thus “prop-apart”, or support the opening of the fracture, yet remain highly permeable to hydrocarbon fluid flow since they form a packed bed of particles with interstitial void space connectivity.

To begin a fracturing process, at least one perforation is made at a particular down-hole location through the well into a subterranean formation, e.g. through a wall of at least one casing section, to provide fluid communication between the wellbore interior and the formation.

One challenge in maintaining fluid communication through the perforations is that the size of the perforations (aperture size or aperture diameter) in the wellbore casing sections begins to change as the edges erode. These erosions introduce uncertainties in otherwise controllable parameters, such as fluid pressure and flow rates. Aspects of the disclosed technology address these challenges by providing solutions for preventing erosion to perforation edges through the use of erosion resistant inserts. Additionally, aspects of the disclosed technology provide techniques for improving the perforation process, for example, by providing selectively removable plugs that are disposed within the inserts and which can be removed to form fluid communication channels without the use of perforating guns.

In some implementations, the disclosed technology encompasses wear-resistant inserts that are disposed around the peripheral edge of the perforations to arrest erosive enlargement that can occur during hydraulic fracturing treatment. The inserts can be filled with a selectively removable plug, for example, that can be removed to open fluid communication holes (perforations) between the wellbore interior and the outside formation. Use of removable plugs can be used to eliminate the need of running perforating guns inside the casing, as well as surface wireline equipment that is required to operate the perforating guns.

In practice, casing sections of a casing string are prepared before being run downhole. This process includes the creation of perforations in the wall of various casing sections, and the installation of wear-resistant sealed inserts around the edges of the perforations. The inserts may be constructed of different types of wear-resistant materials, for example, including but not limited to: tool steels, metal nitrides, metal carbides, hard chromium, cemented tungsten carbide, or ceramics. Moreover, the inserts may be coated or hard-faced with powders or particulates, including diamond, through various processes such as thermal spray coating, chemical vapor deposition, or electroplating. Regardless of the material selected or process employed, the key requirement for the insert is surface hardness, which should be equal to or above 40 Rockwell C (40 HRC, approximately 400 Vickers scale). Depending on the desired implementation, inserts may be affixed by various means, including but not limited to: welding, brazing, adhesives, threads, shrink-fits, press-fits, glass-to-metal seals, and/or ceramic-to-metal seals, and the like. In some instances, the inserts can be disposed in particular angular pattern and/or longitudinal spading to fit specific extraction needs or scenarios. For example, the angular pattern may simply be zero degrees (i.e., all inserts are co-linear down the length of the casing) or may be some other phasing such as 2@180 degrees, 3@120 degrees, 6@60 degrees, and so forth. Moreover, the longitudinal spacing may be a few inches within a single perforation cluster up to several feet to enable separation of one cluster to another.

Once the inserts have been installed, a removable plugging material can be inserted to seal an interior volume of the casing string. As discussed in further detail below, plugs can be made of different materials, and can be installed in different configurations, depending on the desired removal process that is to be implemented.

The disclosure now turns to FIGS. 1A and 1B provide a brief introductory description of the larger systems that can be employed to practice the concepts, methods, and techniques disclosed herein. A more detailed description of the methods and systems for implementing the improved semblance processing techniques of the disclosed technology will then follow.

FIG. 1A shows an illustrative drilling environment 100. Within environment 100, drilling platform 102 supports derrick 104 having traveling block 106 for raising and lowering drill string 108. Kelly 110 supports drill string 108 as it is lowered through rotary table 112. Drill bit 114 is driven by a downhole motor and/or rotation of drill string 108. As bit 114 rotates, it creates a borehole 116 that passes through various formations 118. Pump 120 circulates drilling fluid through a feed pipe 122 to kelly 110, downhole through the interior of drill string 108, through orifices in drill bit 114, back to the surface via the annulus around drill string 108, and into retention pit 124. The drilling fluid transports cuttings from the borehole into pit 124 and aids in maintaining borehole integrity.

Downhole tool 126 can take the form of a drill collar (i.e., a thick-walled tubular that provides weight and rigidity to aid the drilling process) or other arrangements known in the art. Further, downhole tool 126 can include various sensor and/or telemetry devices, including but not limited to: acoustic (e.g., sonic, ultrasonic, etc.) logging tools and/or one or more magnetic directional sensors (e.g., magnetometers, etc.). In this fashion, as bit 114 extends the borehole through formations 118, the bottom-hole assembly (e.g., directional systems, and acoustic logging tools) can collect various types of logging data. For example, acoustic logging tools can include transmitters (e.g., monopole, dipole, quadrupole, etc.) to generate and transmit acoustic signals/waves into the borehole environment. These acoustic signals subsequently propagate in and along the borehole and surrounding formation and create acoustic signal responses or waveforms, which are received/recorded by evenly spaced receivers. These receivers may be arranged in an array and may be evenly spaced apart to facilitate capturing and processing acoustic response signals at specific intervals. The acoustic response signals are further analyzed to determine borehole and adjacent formation properties and/or characteristics.

For purposes of communication, a downhole telemetry sub 128 can be included in the bottom-hole assembly to transfer measurement data to surface receiver 130 and to receive commands from the surface. In some implementations, mud pulse telemetry may be used for transferring tool measurements to surface receivers and receiving commands from the surface; however, other telemetry techniques can also be used, without departing from the scope of the disclosed technology. In some embodiments, telemetry sub 128 can store logging data for later retrieval at the surface when the logging assembly is recovered. These logging and telemetry assemblies consume power, which must often be routed through the directional sensor section of the drill string, thereby producing stray EM fields which interfere with the magnetic sensors.

At the surface, surface receiver 130 can receive the uplink signal from downhole telemetry sub 128 and can communicate the signal to data acquisition module 132. Module 132 can include one or more processors, storage mediums, input devices, output devices, software, and the like as described in further detail below. Module 132 can collect, store, and/or process the data received from tool 126 as described herein.

At various times during the drilling process, drill string 108 may be removed from the borehole as shown in example environment 101, illustrated in FIG. 1B. Once drill string 108 has been removed, logging operations can be conducted using a downhole tool 134 (i.e., a sensing instrument tool) suspended by a conveyance 142. In one or more embodiments, the conveyance 142 can be a cable having conductors for transporting power to the tool and telemetry from the tool to the surface. Downhole tool 134 may have pads and/or centralizing springs to maintain the tool near the central axis of the borehole or to bias the tool towards the borehole wall as the tool is moved downhole or uphole.

Downhole tool 134 can include various directional and/or acoustic logging instruments that collect data within borehole 116. A logging facility 144 includes a computer system, such as those described with reference to FIGS. 5 and 6, discussed below. In one or more embodiments, the conveyance 142 of downhole tool 134 can be at least one of wires, conductive or non-conductive cable (e.g., slickline, etc.), as well as tubular conveyances, such as coiled tubing, pipe string, or downhole tractor. Downhole tool 134 can have a local power supply, such as batteries, downhole generator and the like. When employing non-conductive cable, coiled tubing, pipe string, or downhole tractor, communication can be supported using, for example, wireless protocols (e.g. EM, acoustic, etc.), and/or measurements and logging data may be stored in local memory for subsequent retrieval.

Although FIGS. 1A and 1B depict specific borehole configurations, it is understood that the present disclosure is equally well suited for use in wellbores having other orientations including vertical wellbores, horizontal wellbores, slanted wellbores, multilateral wellbores and the like. While FIGS. 1A and 1B depict an onshore operation, it should also be understood that the present disclosure is equally well suited for use in offshore operations. Moreover, the present disclosure is not limited to the environments depicted in FIGS. 1A and 1B, and can also be used in either logging-while-drilling (LWD) or measurement while drilling (MWD) operations.

FIG. 2 illustrates steps of an example process 200 for constructing a wellbore casing string, according to some aspects of the disclosed technology. Process 200 begins with step 202 in which at least one aperture (perforation) is inserted into at least one side wall of a casing section. In some embodiments, the size (e.g., diameter) and placement of the aperture is based on the intended drilling application, such as based on formation or wellbore characteristics in which the casing string is deployed. In some approaches, the aperture size can be optimized based on characteristics of the hydraulic fracturing setup. By knowing the size and number of apertures in a particular casing section, fluid distribution (e.g., fluid pressure, velocity, and/or flow rate) can be more accurately controlled during the hydraulic fracturing process.

In step 204, an insert is affixed around a periphery of the aperture. The insert can be composed of an erosion resistant material, such as a tungsten carbide material, or other material that can resist erosion caused by the ingress/egress of various drilling fluids and hydrocarbons through the aperture in the casing wall. The insert may be affixed using different means, including but not limited to: welding, brazing, adhesives, threads, shrink-fits, press-fits, glass-to-metal seals, and/or ceramic-to-metal seals, and the like.

In step 206, a plug is placed within the insert. In some approaches, the plug is selectively removable, and serves to provide a temporary seal in the casing wall, for example, while the casing string is run into the wellbore, and wellbore completion operations completed. Once fracturing/production is commenced, the various plugs in the one or more different casing sections can be selectively removed to permit fluid communication with the formation. Opening of fluid channels can involve the removal of the plug in various ways. As such, the plug is comprised of materials that break or disintegrate when exposed to heat, chemicals, and/or mechanical shock. As discussed in further detail below, the plug can be one or more of a ceramic disc, for example, that can be shattered with mechanical shock (e.g., caused by an explosive device), or from pressure, heat, dissolution, or corrosive attack caused by a chemical reaction.

FIG. 3 is a cut-away view of a casing string 300 with multiple casing sections 302 (e.g., casing sections 302A and 302B), according to some aspects of the disclosed technology. Casing string 300 includes sections 302 that are joined by fitting 304. As further illustrated, each casing section (302A, 302B) includes one or more plugged apertures (perforations) 306 (e.g., 306A, 306B, 306C, and 306D) that permit communication between an interior volume of casing string 300 and the exterior. It is understood that casing string 300 can have a greater number of casing sections, fittings and/or plugged apertures, without departing from the scope of the disclosed technology.

As discussed in further detail below, plugged apertures 306 include an insert/plug combination that functions to seal the interior volume of casing string 300. Depending on the desired deployment, the plug material may be designed for removal via a variety of different means, including the use of explosive charges, chemical reactions, or the application of pressure, for example, that results from a chemical reaction. Additional details relating to plug removal are provided in conjunction with FIGS. 5A-6B, discussed below.

FIG. 4A illustrates cut away views (400, 401) of example inserts that contain plugs, according to some aspects of the disclosed technology. In example view 400, an interior volume of insert 402 is entirely filled with a plugging material (plug) 404. As discussed above, plug 404 can be made of a material that is designed to break or shatter in response to mechanical shock (e.g., a ceramic or ceramic composite material). However, in other embodiments, plug 404 can be comprised of materials designed to melt in response to thermal stress, or dissolve when exposed to corrosive chemicals, e.g., chemical cutters. For example, plug 404 may be comprised of a calcium composite or dolomite that is configured to dissolve when contacted by an acid, such as hydrochloric acid, acetic acid, or the like. In example view 401, plug 406 is configured to have an empty interior volume 408.

FIG. 4B illustrates a cut away view of a wellbore 403 including a casing section 410 having an insert 402, according to some aspects of the disclosed technology. In the example of FIG. 4B, the exterior of casing section 410 is surrounded by concrete 410 that, in turn, is adjacent to a formation 407. In this example, it is understood that casing section 410 can represent only a single casing section from among multiple sections forming a casing string extending down wellbore 403.

Casing section 410 includes an insert 402 that is configured to prevent erosion of casing section 410 once fluid communication has been established between wellbore 403 and formation 407. To establish this communication, plug 404 can be selectively removed from insert 402, for example, to permit fracturing fluids to be pumped out of wellbore 403 and into formation 407, as well as to permit hydrocarbons to flow back into wellbore 403 from formation 407. As discussed in further detail below with respect to FIGS. 5A-6B, plug 404 may be selectively removed using signals sent from the surface that are designed to cause the removal of plug 404. e.g., via mechanical force, heat, pressure and/or chemical erosion, etc.

FIG. 5A is a cut away view a wellbore 500 utilizing a casing string 504 in which a detonating cord 516 is configured to remove a casing plug 508, according to some aspects of the disclosed technology. In the example of FIG. 5A, a centralizer 514 is disposed on an outside surface of casing string 504, within cement layer 506. In this configuration, centralizer 514 is configured to house plug 512, as well as a detonating cord 516, which can be used to selectively remove exterior plug 512 and casing plug 508, for example, to permit fluid communication between wellbore 500 and formation 510.

FIG. 5B is a cut away view of a wellbore 501 utilizing a casing string in which an explosive device 518 (e.g., shape charge and/or detonating cord) are configured to remove an interior casing plug 509, and exterior plug 513. according to some aspects of the disclosed technology. Similar to the example of FIG. 5A, a centralizer 514 is disposed on an outside surface of casing string 504, within cement layer 506. In this configuration, centralizer 514 is configured to house explosive device 518, which can be used to selectively remove exterior plug 513 and casing plug 509, for example, to permit fluid communication between wellbore 501 and formation 510.

FIG. 6A is a cut away view of a wellbore 600 utilizing a casing string 604 in which an erosive chemical containment device 620 is configured to remove a casing plug, according to some aspects of the disclosed technology. In this configuration, chemical containment device 620 is configured to be selectively activated, for example, using a remotely activate chemical release device 612, that is disposed adjacent to chemical containment device 620. For example, activation of the remotely activated chemical release device 621 can cause chemical containment device 620 to rupture, thereby exposing casing plug 609 and exterior plug 612 to chemically induced pressure, heat, or erosion (e.g., using an acid). As such, removal of casing plug 609 and exterior plug 615 can be remotely controlled in order to facilitate fluid communication between wellbore 600 and formation 610.

FIG. 6B is a cut away view of a wellbore 601 utilizing a casing string in which multiple chemical containment devices 618A, 618B are configured to facilitate removal of plugs 609, 615, according to some aspects of the disclosed technology.

In this configuration, chemical containment devices 618A, 618B are configured to be selectively activated, for example, using a remotely activate chemical release device 622. Activation of chemical release device 622 can cause chemical containment devices 618A, 618B to rupture to permit a mixing of the chemicals contained therein. In some aspects, mixing of the contents of chemical containment devices 618A, 618B can be used to cause heat (e.g., through a thermal chemical reaction) and/or pressure (e.g., through an acid/base reaction) that is sufficient to break (or dissolve) plugs 609 and/or 615.

In some aspects, an acidic chemical cutter, such as bromine tri-fluoride may be used to corrode or dissolve the plug; however, it is understood that other chemicals or chemical combinations may be used, without departing from the scope of the disclosed technology. By way of example, an acid such as hydrochloric acid, acetic acid and/or formic acid may be used to dissolve calcium carbonate or dolomite type plugs. It is understood that the selection of chemical cutter can be based on a material of the plug used, which may vary, depending on the desired implementation.

FIG. 7 illustrates an exemplary computing system 700 for use with example tools and systems (e.g., tool 126). The more appropriate embodiment will be apparent to those of ordinary skill in the art when practicing the present technology. Persons of ordinary skill in the art will also readily appreciate that other system embodiments are possible.

Specifically, FIG. 7 illustrates system architecture 700 wherein the components of the system are in electrical communication with each other using a bus 705. System architecture 700 can include a processing unit (CPU or processor) 710, as well as a cache 712, that are variously coupled to system bus 705. Bus 705 connects various system components including system memory 715, (e.g., read only memory (ROM) 720 and random-access memory (RAM) 725), to processor 710. System architecture 700 can include a cache of high-speed memory connected directly with, in close proximity to, or integrated as part of the processor 710. System architecture 700 can copy data from the memory 715 and/or the storage device 730 to the cache 712 for quick access by the processor 710. In this way, the cache can provide a performance boost that avoids processor 710 delays while waiting for data. These and other modules can control or be configured to control the processor 710 to perform various actions. Other system memory 715 may be available for use as well. Memory 715 can include multiple different types of memory with different performance characteristics. Processor 710 can include any general-purpose processor and a hardware module or software module, such as module 1 (732), module 2 (734), and module 3 (736) stored in storage device 730, configured to control processor 710 as well as a special-purpose processor where software instructions are incorporated into the actual processor design. Processor 710 may essentially be a completely self-contained computing system, containing multiple cores or processors, a bus, memory controller, cache, etc. A multi-core processor may be symmetric or asymmetric.

To enable user interaction with the computing system architecture 700, input device 745 can represent any number of input mechanisms, such as a microphone for speech, a touch-sensitive screen for gesture or graphical input, keyboard, mouse, motion input, and so forth. An output device 742 can also be one or more of a number of output mechanisms. In some instances, multimodal systems can enable a user to provide multiple types of input to communicate with the computing system architecture 700. The communications interface 740 can generally govern and manage the user input and system output. There is no restriction on operating on any particular hardware arrangement and therefore the basic features here may easily be substituted for improved hardware or firmware arrangements as they are developed.

Storage device 730 is a non-volatile memory and can be a hard disk or other types of computer readable media which can store data that are accessible by a computer, such as magnetic cassettes, flash memory cards, solid state memory devices, digital versatile disks, cartridges, random access memories (RAMs) 735, read only memory (ROM) 720, and hybrids thereof.

Storage device 730 can include software modules 732, 734, 736 for controlling the processor 710. Other hardware or software modules are contemplated. The storage device 730 can be connected to the system bus 705. In one aspect, a hardware module that performs a particular function can include the software component stored in a computer-readable medium in connection with the necessary hardware components, such as the processor 710, bus 705, output device 742, and so forth, to carry out various functions of the disclosed technology.

Embodiments within the scope of the present disclosure may also include tangible and/or non-transitory computer-readable storage media or devices for carrying or having computer-executable instructions or data structures stored thereon. Such tangible computer-readable storage devices can be any available device that can be accessed by a general purpose or special purpose computer, including the functional design of any special purpose processor as described above. By way of example, and not limitation, such tangible computer-readable devices can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other device which can be used to carry or store desired program code in the form of computer-executable instructions, data structures, or processor chip design. When information or instructions are provided via a network or another communications connection (either hardwired, wireless, or combination thereof) to a computer, the computer properly views the connection as a computer-readable medium. Thus, any such connection is properly termed a computer-readable medium. Combinations of the above should also be included within the scope of the computer-readable storage devices.

Computer-executable instructions include, for example, instructions and data which cause a general-purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Computer-executable instructions also include program modules that are executed by computers in stand-alone or network environments. Generally, program modules include routines, programs, components, data structures, objects, and the functions inherent in the design of special-purpose processors, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of the program code means for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps.

Other embodiments of the disclosure may be practiced in network computing environments with many types of computer system configurations, including personal computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. Embodiments may also be practiced in distributed computing environments where tasks are performed by local and remote processing devices that are linked (either by hardwired links, wireless links, or by a combination thereof) through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.

The various embodiments described above are provided by way of illustration only and should not be construed to limit the scope of the disclosure. For example, the principles herein apply equally to optimization as well as general improvements. Various modifications and changes may be made to the principles described herein without following the example embodiments and applications illustrated and described herein, and without departing from the spirit and scope of the disclosure. Claim language reciting “at least one of” a set indicates that one member of the set or multiple members of the set satisfy the claim.

STATEMENTS OF THE DISCLOSURE

Statement 1: a casing string configured for facilitating hydrocarbon extraction from a wellbore, the casing string including: at least one casing section, an aperture disposed on a surface of the of the at least one casing section, an insert affixed around a periphery of the aperture; and a plug disposed within the insert, wherein the plug is configured to be selectively removable to allow fluid communication between an interior volume of the casing string and an exterior of the casing string adjacent to a geologic formation.

Statement 2: the casing string of statement 1, wherein the insert is configured to prevent erosion of the internal edge of the aperture in order to maintain a diameter of the aperture.

Statement 3: the casing string of any of statements 1-2, wherein the insert comprises a carbide composite.

Statement 4: the casing string of any of statements 1-3, wherein the plug is configured to be removed from the insert by an explosive charge.

Statement 5: the casing string of any of statements 1-4, wherein the plug is configured to be removed from the insert by heat.

Statement 6: the casing string of any of statements 1-5, wherein the plug is configured to dissolve upon contact with a chemical cutter.

Statement 7: the casing string of any of statements 1-6, wherein the chemical solution comprises bromine tri-fluoride.

Statement 8: the casing string of any of statements 1-7, wherein the chemical solution comprises an acid.

Statement 9: the casing string of any of statements 1-8, wherein the plug comprises zinc.

Statement 10: the casing string of any of statements 1-9, wherein the plug comprises aluminum.

Statement 11: the casing string of any of statements 1-10, wherein the plug comprises ceramic and calcium carbonate.

Statement 12: a method for constructing a casing string configured for facilitating hydrocarbon extraction from a wellbore, the casing string including: inserting an aperture in at least one casing section, wherein the aperture is disposed on a surface of the of the at least one casing section; affixing an insert around a periphery of the aperture; and placing a plug within the insert, wherein the plug is configured to be selectively removable to allow fluid communication between an interior volume of the casing string and an exterior of the casing string adjacent to a geologic formation.

Statement 13: the method of statement 12, wherein the insert is configured to prevent erosion of the internal edge of the aperture in order to maintain a diameter of the aperture.

Statement 14: the method of any of statements 12-13, wherein the insert comprises a carbide composite.

Statement 15: the method of any of statements 12-14, wherein the plug is configured to be removed from the insert by an explosive charge.

Statement 16: the method of any of statements 12-15, wherein the plug is configured to be removed from the insert by heat.

Statement 17: the method of any of statements 12-16, wherein the plug is configured to dissolve upon contact with a chemical cutter.

Statement 18: the method of any of statements 12-17, wherein the chemical solution comprises bromine tri-fluoride.

Statement 19: the method of any of statements 12-18, wherein the chemical solution comprises an acid.

Statement 20: a wellbore casing section, comprising: at least one aperture disposed on a surface of the casing section; an insert affixed around a periphery of the aperture; and a plug disposed within the insert, wherein the plug is configured to be selectively removable to facilitate communication between an interior volume of the casing section and an exterior of the casing section.

FLUID COMMUNICATION METHOD FOR HYDRAULIC FRACTURING

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