Patent Application
20250146389
Embodiments disclosed herein generally relate to perforating systems including charge dispensers, carriers such as perforating guns, and related components and methods. More particularly, at least some embodiments relate to systems, hardware, and methods, for and/or relating to the construction and use of charge dispensers.
Shaped charges have come into use for a variety of processes, including perforating processes performed in conjunction with hydraulic fracturing, or ‘frac'ing,’ which began in the mid-20th century. Shaped charges offered a solution to the industry need for efficient well perforation, enabling better reservoir access and improving overall production rates.
The concept of a shaped charge was initially developed during World War II for military purposes. A shaped charge included an explosive charge encased in a metal liner that, upon detonation, transformed into a high-velocity jet with exceptional penetration capabilities. Recognizing the potential of this technology, the oil and gas industry adapted shaped charges to perforate well casings and surrounding rock formations to enhance reservoir production.
In oil and gas applications, shaped charges are deployed within perforating guns, also referred to herein as a ‘perf gun’ or simply a ‘gun,’ configured to house and detonate these charges. The subsequent perforations in the well casing and nearby formations facilitate the flow of hydrocarbons, crucial for the production process.
Presently, shaped charges are used in oil and gas well completions, particularly for hydraulic fracturing operations. In brief, a frac'ing process involves lowering perforating guns into the wellbore to precise depths and detonating the shaped charges, which penetrate the casing and surrounding formations. These perforations create pathways for the hydrocarbons to flow, enhancing production rates and enabling efficient frac'ing. While such methods have proven generally effective in some circumstances, various challenges remain.
One such challenge concerns inconsistencies in perforation geometry and dimensions. For example, creating a perfectly cylindrical, or nearly cylindrical, hole, and/or geometrically consistent holes in the casing, using shaped charge perforating guns, is a complex task due to various challenges inherent in the process. Despite advancements in technology, achieving precision in hole geometry remains challenging. Following is a discussion of some particular challenges.
Examples of such challenges concern stand-off distance, and jet formation. Stand-off distance variation refers to variation in the distance between the shaped charge and the casing, and may significantly affect hole geometry. For example, deviations in the stand-off distance due to wellbore irregularities or gun positioning can result in non-uniform hole shapes in the casing which, in turn, may negatively impact flow through the associated perforations.
As well, jet formation and penetration, that is, the formation and geometry of the high-velocity jet from the shaped charge, is impacted by the stand-off distance. If the stand-off distance is not consistent, the jet angle and penetration depth can vary, leading to inconsistent hole shapes and sizes which, in turn, may affect hydrocarbon flow into the wellbore.
Other challenges concern materials used for the barrels and carrier, particularly, material interference. The shaped charge is typically housed within a carrier or barrel, often made of steel. The jet formed by the shaped charge must penetrate through this material before hitting the casing. The interaction of the jet with the carrier can cause deviations from a perfectly cylindrical, or other desired, hole shape. As well, the carrier material can negatively affect the integrity and shape of the jet as the jet exits the barrel. If the jet is deformed or fragmented during this initial penetration, it may produce an irregular perforation in the casing.
Still other challenges with conventional approaches concern casing characteristics, such as casing material and thickness. In particular, the material and thickness of the casing influence how the jet behaves upon impact. Variations in casing material properties or thickness can cause the jet to deform, thereby affecting the hole geometry. A related challenge concerns casing integrity. Particularly, the structural integrity, or lack thereof, of the casing can also impact hole formation and geometry. Corrosion, damage, or weak points in the casing can lead to unpredictable hole shapes and sizes upon perforation.
Well conditions, such as pressure and temperature for example, can also present challenges with respect to conventional approaches. More specifically, downhole conditions, including pressure and temperature, can affect the behavior of the shaped charge and the resulting jet. Deviations from the expected downhole conditions can alter the jet performance and, consequently, the hole geometry that results from the jet.
As a final example, formation heterogeneity can affect the holes produced by shape charges. Particularly, the geological variations in the formation surrounding the casing can influence the behavior of the jet. Heterogeneous formations may cause the jet to deviate or disperse irregularly upon impact.
In order to describe the manner in which at least some of the advantages and features of one or more embodiments may be obtained, a more particular description of embodiments will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments and are not therefore to be considered to be limiting of the scope of this disclosure, embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings.
Embodiments disclosed herein generally relate to perforating systems including charge dispensers, carriers such as perforating guns, and related components and methods. More particularly, at least some embodiments relate to systems, hardware, and methods, for and/or relating to the construction and use of charge dispensers.
One example embodiment comprises a charge dispenser, which may be reusable, that is configured to be carried in a reloadable perf gun. An embodiment of a charge dispenser may comprise, for example, a body, an internal barrel defined in the body and communicating with an exit muzzle, a projectile chamber and throat, as well as a propellant chamber for housing and containing the propellant, and or propellants. All of these elements may be integrally formed to implement an individual charge dispenser. The charge dispenser may also contain an ignition jack that enables a feed through wire to enter the body and connect to an ignitor, or ignition device, that is located in the propellant chamber.
Embodiments, such as the examples disclosed herein, may be beneficial in a variety of respects. For example, and as will be apparent from the present disclosure, one or more embodiments may provide one or more advantageous and unexpected effects, in any combination, some examples of which are set forth below. It should be noted that such effects are neither intended, nor should be construed, to limit the scope of the claims in any way. It should further be noted that nothing herein should be construed as constituting an essential or indispensable element of any embodiment. Rather, various aspects of the disclosed embodiments may be combined in a variety of ways so as to define yet further embodiments. For example, any element(s) of any embodiment may be combined with any element(s) of any other embodiment, to define still further embodiments. Such further embodiments are considered as being within the scope of this disclosure. As well, none of the embodiments embraced within the scope of this disclosure should be construed as resolving, or being limited to the resolution of, any particular problem(s). Nor should any such embodiments be construed to implement, or be limited to implementation of, any particular technical effect(s) or solution(s). Finally, it is not required that any embodiment implement any of the advantageous and unexpected effects disclosed herein.
In particular, one advantageous aspect of an embodiment is that an embodiment may avoid, reduce, or eliminate, any one, or more, of the problems and challenges noted herein. An embodiment may comprise a charge dispenser that is reusable for multiple perforation operations. Various other aspects of one or more embodiments will be apparent from this disclosure.
Following is a discussion of some context for one or more embodiments. This discussion is not intended to limit the scope of the disclosure, or of any claims, in any way.
Conventional perforating guns with shaped charges are configured for single-use, making them both expensive and environmentally wasteful. After detonation, the equipment is rendered unusable and often discarded, contributing to resource inefficiency and waste management challenges. The utilization of shaped charge perforating guns in the oil and gas industry is highly effective for creating perforations in well casings and surrounding formations. However, a significant drawback is that the majority of materials used in the perforating gun system are configured only for a single-use, resulting in substantial waste. That is, such materials are employed as consumable items. Following is an overview of some examples of the materials wasted or consumed, and the environmental implications, of this conventional single-use approach to shaped charges and sub components when perforating oil and gas wells.
RDX (cyclotrimethylenetrinitramine) and HMX (cyclotetramethylenetetranitramine) are common explosives used in shaped charges. Once detonated, they are consumed in the explosion, rendering them unusable for subsequent operations.
Detonation cord, or ‘det cord,’ initiates the explosion in the shaped charge. Det cord is a one-time-use component, consumed during the detonation process. As another example, blasting caps are used to initiate the detonation cord, and like the det cord, blasting caps are single-use components, expended during the perforating operation.
The copper liner inside the shaped charge deforms to form the high-velocity jet during detonation. Once deformed, the copper liner loses its structural integrity and cannot be reformed or reused.
The barrels, from which the shaped charges are fired, may be made from alloy steel such as 4140, and undergo permanent deformation when the shaped charges are detonated and the high velocity plasma jet burns through the barrel body. The explosion that occurs inside of the barrel when the shaped charges are detonated also causes permanent deformation to the barrel, rendering the barrel unusable for further operations.
The carriers, which may be made of aluminum and or steel, house the shaped charges and provide structural support. The explosion renders the carrier and its components unusable for any subsequent perforations.
In conventional systems, various fluids are used for transport. In particular, the fluids that are utilized to transport and lower the perforating guns down the wellbore are often rendered contaminated or unusable for future operations due to exposure to explosive residues and wellbore conditions.
The use of consumable materials, such as the examples listed above, may have a variety of implications with respect to the environment. Following are some illustrative examples.
One such implication concerns resource depletion. Particularly, the single-use nature of these materials depletes valuable resources like metals and the materials used in the energetics, or explosives, requiring continuous production and extraction of these materials.
Another concern is the environmental footprint of conventional approaches. The manufacturing, usage, and disposal of consumable, single-use, materials such as those noted above contribute to the carbon footprint and environmental impact of the oil and gas industry.
As well, waste disposal poses challenges. Particularly, disposal of the expended materials poses a significant waste management challenge. Copper liners, steel carriers, barrels, and explosives require specialized and safe disposal methods.
Financial costs are another factor to be considered. The cost of producing and procuring these consumable materials, especially the explosives, adds to the overall financial burden on oil and gas companies. At present, the conventional single-use perforating gun approach, with the use of shaped charges, remains the prevalent practice, highlighting the need for continued innovation in this area to, among other things, minimize waste and environmental impact, and the associated costs.
The use of conventional shaped charge perforating guns poses inherent safety risks due to the high explosives involved. Proper handling, transportation, and disposal are important to ensuring the safety of workers and the environment. Working with shaped charges, particularly in the context of oil and gas perforating guns, involves inherent safety risks due to the highly explosive nature of the materials involved. The safety concerns associated with using shaped charges for well perforation are multifaceted and require strict adherence to safety protocols and comprehensive training. Following is a discussion of some safety concerns.
One particular concern is high explosive content. Shaped charges contain high-explosive (HE) materials like RDX, HMX, or similar compounds. These explosives are highly sensitive to shock, friction, and temperature, making them potentially hazardous to handle, transport, and store. Another concern is risk of accidental detonation. Accidental impact, friction, or mishandling can cause premature detonation, resulting in serious injuries or fatalities, and property damage. As well, there are handling and transportation risks associated with high explosives such as are used in perforating processes. One particular example is shock sensitivity. Shaped charges can be sensitive to shocks during handling and transportation, making proper packaging and secure transport essential to mitigate accidental detonations. Fall and impact hazards may also be presented. Dropping or impacting the shaped charges can lead to unintended detonation, risking harm to personnel and equipment.
Other safety concerns relate to initiation mechanisms. For example, shaped charges use blasting caps or detonation cords as initiation mechanisms. Mishandling or improper attachment of these initiators can lead to unplanned detonations. As another example, external electromagnetic interference can inadvertently activate blasting caps, necessitating precautions in electromagnetic environments.
Further safety concerns relate to equipment operation, such as misfires for example. A misfire occurs when a shaped charge fails to detonate. Incomplete perforations can result in inefficient well stimulation during hydraulic fracturing, requiring careful identification and remediation. As well, the high-velocity jet and fragments produced during detonation can pose risks to personnel and nearby equipment, necessitating safe standoff distances and protective measures.
Shaped charges such as are used in conventional approaches may present various environmental and occupational hazards, such as toxic fumes and residues. Detonation produces potentially harmful fumes and residues, necessitating adequate ventilation and personal protective equipment (PPE) to mitigate inhalation risks. Contamination risks may also be present in which contamination of the wellbore, surrounding environment, or groundwater can occur if shaped charges are not handled, deployed, or disposed of properly, posing environmental hazards.
Conventional shape charges also present storage and disposal risks. For example, proper storage of shaped charges is critical to prevent accidental detonation, necessitating secure storage facilities and adherence to safety regulations. As well, disposing of unused or expired shaped charges requires specialized procedures and adherence to environmental regulations to minimize risks to personnel, equipment, and the environment.
The ignition of HMX and RDX, which are powerful high-explosive compounds that are used in shaped charges for perforating oil and gas wells during the frac'ing process, can result in contamination of water if a shaped charge is fired in a water environment. The contamination arises from the byproducts and residues generated during the combustion and detonation processes. Following is an overview of example potential contaminants and their implications with respect to water quality.
One such contaminant is nitrogen oxides (NOx). During the combustion and detonation of HMX and RDX, nitrogen oxides (NOx) are released. These compounds include nitrogen dioxide (NO2) and nitric oxide (NO), which are harmful to human health and the environment. They can lead to acidification of water bodies, posing risks to aquatic life.
Another contaminant is carbon residues. Particularly, the incomplete combustion of HMX and RDX may produce carbon residues, which can contaminate the water. These residues can contribute to the degradation of water quality, affecting both aquatic organisms and the ecosystem.
Finally, The ignition of HMX and RDX may release toxic gases and vapors, such as hydrogen cyanide (HCN), which can pose significant health risks if dissolved in water. HCN can harm aquatic life and contaminate the water, affecting its quality and safety.
In the context of hydraulic fracturing, or ‘frac'ing,’ achieving uniformly cylindrical and consistent hole sizes in the casing can be important for maximizing the overall effectiveness of the frac'ing process. This is due to the fact that the perforations in the casing serve as the conduits through which fracturing fluids are pumped into the reservoir, and through which gases, liquids, and fluids from the formation flow into the casing.
Following is a discussion of some useful aspects of uniform and perfectly cylindrical, or nearly perfectly cylindrical, perforations such as may be achieved by a charge dispenser—and/or associated charge—according to one or more embodiments, and used during a frac'ing, or other downhole, process according to one or more embodiments. It is noted that as used herein, a ‘cylindrical’ hole, or perforation, created by a charge dispenser according to one embodiment embraces a hole whose cylindricity falls within a range, or ranges. Some example ranges for one or more embodiments, defined with reference to the diameter of the perforation, include (1) plus or minus 1 (one) percent of the perforation diameter, (2) plus or minus 1.5 (one and one-half) percent of the perforation diameter, and/or (3) plus or minus 3.0 (three) percent of the perforation diameter. In one example embodiment, a perforation with a diameter of 0.5 (one half) inches has a cylindricity in a range of 0.2 percent of the perforation diameter to 0.6 percent of the perforation diameter.) All of the aforementioned ranges are inclusive of the stated upper and lower limits. It is further noted that no hole, or any other aspect of any embodiment, is required to possess, implement, or enable implementation of, any of the following aspects.
A cylindrical hole in the casing may ensure that the hydraulic fracturing fluid passing through the hole is evenly distributed across the reservoir. Uniformity in hole size and shape helps in maintaining consistent flow rates through each perforation, preventing imbalances in fluid distribution. This balance may be important for achieving uniform pressure within the reservoir and promoting optimal fracturing of the rock formation.
A cylindrical hole provides equal stress distribution along its circumference. When fracturing fluids are pumped through uniformly cylindrical perforations, the stress exerted on the formation is distributed evenly. In an embodiment, this even stress distribution may be important for initiating and propagating fractures in a controlled and predictable manner.
Cylindrical holes, when achieved/achievable, may help to facilitate a smoother flow of fracturing fluids during hydraulic fracturing. The smooth flow helps in reducing pressure drop and turbulence, resulting in more effective fracture propagation. The uniform hole geometry may enable a more predictable and efficient expansion of fractures within the reservoir.
Uniform hole sizes and shapes may ensure a consistent surface area for fluid-rock interaction during the fracturing process. This consistency can be important because the surface area directly influences the extent and efficiency of the fracturing process. In an embodiment, a uniform surface area may enable precise calculations and estimations related to the amount of fracturing fluid needed for an operation.
During the hydraulic fracturing process, proppants, such as sand for example, are mixed with the fracturing fluid and pumped into the reservoir to prop open the fractures created by firing the perf gun. Uniform hole sizes aid in efficient proppant placement, ensuring that the proppant is evenly distributed across all perforations. This even distribution enhances the stability and conductivity of the created fractures.
Uniform perforations may contribute to the creation of a predictable fracture network within the reservoir. The consistency in hole geometry and surface area enables operators to anticipate the fracture patterns and behavior, aiding in the design and execution of the frac job for optimal reservoir stimulation.
In an embodiment, a charge dispenser may create, and/or enable creation of, one or more holes in a casing and/or in a formation, any or all of which holes may possess one or more of the various features disclosed herein. Following is a discussion of aspects of an example embodiment of a charge dispenser, aspects of an example embodiment of a method for using an embodiment of a charge dispenser, and some example use cases for an embodiment of a charge dispenser.
In one embodiment, a charge dispenser is configured to be carried in a reloadable perf gun. An embodiment of a charge dispenser may comprise, for example, a body, an internal barrel defined in the body and communicating with an exit muzzle, a projectile chamber and throat, as well as a propellant chamber for housing and containing the propellant, and or propellants. All of these elements may be integrally formed to implement an individual charge dispenser. The charge dispenser may also contain an ignition jack that allows for a feed through wire to enter the body and connect to an ignitor, or ignition device, that is located in the propellant chamber.
The charge that may be loaded into the propellant chamber of the charge dispenser may be a propellant. Shaped charges may be loaded with energetic, or explosive materials such as HMX or RDX.
Propellants and energetics are both materials with energetic properties, meaning they can undergo combustion or a controlled exothermic chemical reaction to produce heat, gas, and pressure. However, they serve different purposes and have distinct characteristics that determine their safety and environmental impact.
Definition and Purpose: Propellants are energetic materials primarily configured for controlled burning or combustion. They are used to propel projectiles or vehicles, such as rockets, projectiles, and fireworks. In terms of environmental impact, propellants generally produce fewer harmful byproducts during combustion, making them less environmentally toxic compared to high explosives.
Composition: Propellants usually consist of a fuel and an oxidizer. Commonly, the fuel is a carbon-rich compound, and the oxidizer provides the necessary oxygen for combustion. Binders and stabilizers are also added to control the burn rate and enhance safety.
Safety Aspects: Propellants are engineered for controlled combustion, making them relatively stable and safe to handle compared to high explosives. The burn rate of a propellant is managed to prevent abrupt detonation, minimizing the risk of accidental explosions.
Environmental Impact: Propellants generally produce fewer toxic byproducts during combustion compared to high explosives. The controlled combustion process helps in reducing the release of harmful substances into the environment.
Definition and Purpose: Energetics, referred to as high explosives, are energetic materials configured to undergo rapid and violent exothermic reactions, leading to shock waves and high pressures.
Composition: Energetics typically contain a fuel and an oxidizer, like propellants. However, the composition and proportions are such that they result in rapid, nearly instantaneous combustion and release of energy.
Safety Aspects: Energetics are highly sensitive and can undergo unintended detonation due to shock, friction, or heat, making them inherently dangerous to handle. The burn rate in high explosives is extremely rapid, leading to a shockwave that causes damage in the surrounding environment.
Environmental Impact: High explosives produce a significant amount of toxic gases, heat, and pressure during detonation, which can have severe environmental consequences.
Propellants: Safer to handle due to their controlled burn rate and reduced sensitivity to shock and heat.
Energetics: Energetics require more cautious handling and storage procedures due to their sensitivity and potential for accidental detonation.
In an embodiment, a charge dispenser may have the capability to accommodate projectiles, such as bullets for example, having a wide range of different calibers, or diameters, geometries, and shapes, as well as differing lengths and weights. Thus, an embodiment of the charge dispenser may serve as a multi-caliber device. As such, a charge dispenser has the ability to operate and perform in multiple applications that may require a wide range of hole/perforation size requirements. Examples include perforating an oil and gas well that may require more than one hole diameter in the casing wall. Or, perforating one oil and gas well with one caliber projectile, and then being reloaded with a different caliber projectile and perforating a different oil and gas well.
Working principle: An embodiment of a projectile, fired from an embodiment of a charge dispenser, may function according to the principles of conventional firearms and ammunition. In one embodiment, a single charge dispenser may be configured to fire various different calibers of projectiles through the controlled combustion of propellant in a propellant chamber, which propels the projectile.
Safety considerations: controlled combustion: The charge dispenser may be engineered for controlled combustion of propellant, resulting in a controlled expulsion of the projectile. This controlled propulsion minimizes the risk of unintended detonation or violent reactions associated with high explosives. Multiple Calibers: In an embodiment, a charge dispenser can fire different calibers or sizes of projectiles by using corresponding charges. The charge dispenser's barrel and chamber are configured to accommodate specific/different projectile calibers, allowing for versatility in projectile selection.
Working principle: A shaped charge projectile according to one embodiment may utilize a particular configuration to focus explosive energy into a jet aimed at penetrating a target. This jet is formed through a rapid and violent exothermic reaction upon detonation, often employed in oil and gas well perforations or military applications.
Safety considerations: Inherent danger: Shaped charge projectiles utilize high explosives like RDX or HMX, making them inherently dangerous. The formation of a high-velocity jet involves a rapid and violent exothermic reaction, posing significant safety risks if mishandled or triggered accidentally. Single-Use: Shaped charges are configured for single-use, that is, any given shape charge has only one specific caliber or size of projectile. The materials and components of the shaped charge are consumed during detonation, rendering the charge and its components unusable for subsequent firings.
Safety comparison: Projectiles according to one embodiment are safer to be around in terms of accidental discharge and unintended detonation compared to shaped charge projectiles. Controlled combustion: The combustion process of the propellant in the propellant chamber of the gun, is carefully controlled, resulting in predictable projectile propulsion without violent reactions. Safety mechanisms: The gun may have safety features and mechanisms to prevent accidental firing, providing an additional layer of safety to users and bystanders. Safer handling: When handled responsibly and following safety protocols, projectiles are generally safer due to their controlled and predictable behavior.
In one embodiment, a charge dispenser may be used to carry a projectile that may be used perforate oil and gas wells during the frac'ing process. One or more of the charge dispensers may be contained, or housed, within a gun such as an IPG (interlocking perforating gun). The guns, along with the carrier, may be deployed in the wellbore to a designated location, or location of interest, and fired to create perforations, or jet nozzles in the casing that will be used as ports for pumping water and proppant through in order to frac the rock formation. An example embodiment of a charge dispenser is identified at 100 in the accompanying figures, and discussed below.
With attention now to the examples of
As shown in the Figures, an embodiment of the charge dispenser 100 may comprise a generally cylindrical geometry with a barrel 101 centered on a longitudinal axis of the charge dispenser 100. The barrel 101 may be configured have a variety of diameters. A carrier (not shown) may be employed that is configured to removably receive multiple charge dispensers, and the size and configuration of the carrier may be a function of the pipe or casing size where the carrier is to be deployed. The charge dispenser 100, which may be reusable, may be configured to fit multiple different carrier sizes and, in this way, a given charge dispenser 100 may be employed in a variety of different casing/pipe sizes.
The charge dispenser 100 may be coated on any of its surfaces, whether interior or exterior, to reduce the chances of corrosion, or damage in any way. Coating the charge dispenser 100 may enhance the potential of the charge dispenser 100 to work in caustic, abrasive, corrosive, and or high temperature environments such as, but not limited to, subsea and downhole oil and gas wells. Some example coatings that may be used to coat portions of the charge dispenser 100 are disclosed elsewhere herein.
With continued reference to the Figures, a charge dispenser 100 according to one embodiment is an axially symmetrical, that is, symmetrical about its longitudinal axis, cylindrical structure. It may possess a smooth, curved side surface that consistently maintains a circular profile from its base to its upper end. At the base, and as shown in
As shown in the Figures, the example charge dispenser 100 comprises an integrally defined barrel 101. An embodiment of the barrel 101 of the charge dispenser 100 may have various characteristics, examples of which are set forth below.
In one embodiment, the barrel 101 may define confined space where high-pressure gases, generated by the ignition of a propellant, or energetic, can act. The barrel 101 may contain and direct the pressure generated during the firing process, ensuring the force is directed in a forward motion and rapidly propelling the projectile out of the barrel 101.
The barrel 101 may serve as a guide for a projectile. The barrel 101 may also be configured to allow for internal rifling. Rifling may comprise spiral grooves and lands cut into the inner surface of the barrel 101. As a projectile moves through the barrel 101, these grooves engage with the projectile surface, causing the projectile to spin about its longitudinal axis. This spin stabilizes the projectile flight, improving accuracy and reducing the potential of projectile tumbling.
The barrel 101 may be relatively short and compact. The length of the barrel 101 directly affects the muzzle velocity, which is the speed at which a projectile exits the barrel 101. In one embodiment, a barrel 101 length for the charge dispenser 100 may be between 1.480″ to 3.910″ in total length.
The barrel 101 may comprise an inner bore surface 101a, as shown in
In an embodiment, the barrel 101 may have a barrel ID (inside diameter) of between 0.400″ and 0.600″ Such a barrel 101 may thus have a caliber in the range of .400 to .600 inclusive. To illustrate, a .600 caliber barrel 101 may be able to chamber and fire a projectile having an OD (outside diameter) of 0.599″ down to 0.100″ As another example, a .400 caliber barrel may be able to chamber and fire a projectile with an OD of 0.399″ down to 0.100″
As shown in the Figures, the example barrel 101 of the charge dispenser 100 comprises a muzzle 102. An embodiment of the muzzle 102 of the barrel 101 may have various characteristics, examples of which are set forth below.
One function of the muzzle 102 is to provide an exit point, from the barrel 101, for a projectile. Particularly, a projectile passes through the muzzle 102 as it leaves the barrel 101, and travels towards the target.
Another function of the muzzle 102 concerns gas release. Particularly, after a projectile is fired from the barrel 101, the rapidly expanding propellant gases generated by the ignition of the propellant, or energetic, are expelled from the muzzle 102. This release of gas propels the projectile forward.
A further function of the muzzle 102 is accuracy enhancement. Particularly, the shape and finish of the muzzle 102 may enhance the projectile accuracy. A crowned muzzle 102 may ensure that the exiting projectile maintains a stable flight path.
Aesthetic Considerations: An embodiment of the muzzle 102 configuration may also add an aesthetic feature. A distinctive muzzle 102 shape and or profile, may contribute to the appearance of the charge dispenser without affecting the functionality of the muzzle 102.
As shown in the Figures, the example charge dispenser 100 may comprise an ignition jack 104. In an embodiment, the ignition jack may also be considered a passive jack, sometimes also referred to as a “through-hole” or “feedthrough” jack. The ignition jack 104 serves as a conduit for connecting ignition wires together. The ignition jack 104, which may take the form of a simple hole that may be counter bored, may comprise various elements, examples of which are discussed hereafter.
One such element of the example ignition jack 104 is an internal housing frame 104a which may be configured to accommodate a grommet or insulating elastomer or polymer boot that surrounds the wire. The grommet, or boot, may be used to seal off the ignition jack 104 from high pressure liquids and contaminants, pending on the environment the charge dispenser 100 is operating in.
Another element of an example ignition jack 104 is a wire entry hole 104b, which may be sized to accommodate one or more wires and an insulator such as a elastomer boot. The wire entry hole may also be sized to only accommodate a single wire, or multiple wires, and may be epoxied or adhered to the inside of the ignition jack 104.
Finally, an ignition jack 104 may comprise an insulator, such as a plastic, polymer, or elastomer may be used to ensure the wires do not ground or create a short inside the ignition jack. It is noted that no embodiment of the ignition jack 104, or of any other elements of the charge dispenser 100 is required to possess any particular features, aspects, or characteristics.
With particular reference to the example of
The propellant chamber 106 plays a role in the combustion/ignition process, where propellants may be ignited to produce high-speed and energetic gases that create thrust and propel a projectile forward and out of the barrel 101 of the charge dispenser 100.
In an embodiment, the propellant chamber 106 is situated below the projectile chamber 107 and barrel 101. The propellant chamber 106 may be integrally formed as an element of the charge dispenser 101. One function of the propellant chamber 106 is to house, and facilitate the controlled combustion of, the propellant, or propellants.
In an embodiment the propellant chamber 106 geometry may be cylindrical in form, from a top view, and octagonal, from a side view. That is, the propellant chamber 106 may take the form of a cylinder with chamfers 106a at specific angles located at the breech or bottom of the propellant chamber 106, as well as a throat 103, which may be chamfered, at the exit end of the propellant chamber 106 that leads into the projectile chamber.
The throat 103, an embodiment of which is discussed in further detail below, at the exit end of the propellant chamber 106 may, by virtue of the fact that its ID is smaller than the ID of the main body of the propellant chamber 106, increase gas velocity and pressures that may enhance the performance of the charge dispenser 100. It is noted that for incompressible flows, Q=vA, where Q is flow rate, v is velocity, and a is the area defined by the ID—and, for compressible flows, see, e.g., Kaushik, M. (2022). Governing Equations and Thermodynamics of Compressible Flows. In: Fundamentals of Gas Dynamics. Springer, Singapore. https://doi.org/10.1007/978-981-16-9085-3_2).
In an embodiment, the propellant chamber 106 may be configured to accommodate a single propellant that may be in pellet form or loose powder form, and/or may be configured to accommodate multiple powders that may be mixed homogenously, or layered. The choice of propellant, and or propellants, as well as if they are mixed or layered, that may be loaded into the propellant chamber may be based on the application and required performance.
The combustion/ignition process that attends the firing of a charge may generate a significant amount of heat and pressure. The internal walls of the propellant chamber 106 may be coated to modify the physical properties of the material, such as by reducing friction, increasing hardness, and/or, increasing yield strength, so that the propellant chamber 106 may withstand the potential of accelerated temperatures and pressures.
As shown in the Figures, the projectile chamber 107 is located at the base of the barrel 101, and above the throat 103 and propellant chamber 106. In general, the projectile chamber 107 defines a volume in which a projectile may be chambered.
In an embodiment, the throat 103 may serve a specific function in the combustion and ignition process of the propellant or propellants. For example, the throat 103 may ensure that the gases leaving the propellant chamber 106 have a suitably high exit velocity. In an embodiment, the throat 103 defines a constriction, or reduction in cross-sectional flow area, located at the top the propellant chamber 106 and below the projectile chamber 107 and is situated at the forward/exit end of the propellant chamber 106. The constricted geometry of the throat 103 acts as a nozzle.
One purpose of the throat 103 is to accelerate the flow of high-pressure, high- temperature gases generated by the combustion/ignition of propellants in the propellant chamber 106. This acceleration is achieved by the nozzle geometry of the throat 103. In an embodiment, the throat 103 defines the narrowest point, or smallest diameter, in the internal geometry of the charge dispenser 100. The throat 103 may be specifically configured to create a choke point where the gas flow velocity, resulting from ignition of the propellant, reaches its maximum. Finally, the size and shape of the geometry of an embodiment of the throat 103 may be configured based on the specific requirements of the charge dispenser 100, such as, for example, the desired velocity of the projectile, operating conditions, and propellant properties.
With attention now to
In an embodiment, the ignition wire 108 may be configured for power transmission and/or signal transfer. The ignition wire 108 may comprise a wire, cable, or other conductor(s), that may be insulated with Teflon® (polytetrafluoroethylene—PTFE), silicon, or other insulating materials.
In operation, the ignition wire 108 itself, by way of contrast with det cord for example, may not undergo, when connected to an electrical power source, a chemical reaction or other change that would result in its explosion. Instead, in one embodiment, the ignition wire 108 may simply function to transfer a signal or ignition energy to the ignitor 111, and thereby initiate or trigger a controlled ignition process in another device or material located in the propellant chamber 106. Due to its non-explosive nature, in an embodiment, the ignition wire 108 may be considered safe to handle under normal conditions.
In an embodiment, the projectile 109 may comprise an armor piercing projectile, or a projectile configured to penetrate thick steel or alloy walls, cement, concrete, and/or subterranean formations. A projectile 109 may be made of a dense, tough material that may be hard and has high yield strengths, and is configured to penetrate thick, hard, material effectively. The charge dispenser 100, and specifically the chamber 101 for example, may be configured to accommodate multiple different projectile 109 shapes, geometries, sizes, and designs. In an embodiment, the caliber of the projectile 109 may range from .599″ and down to .100″ in outside diameter. The caliber of a given projectile 109 may be dependent on preference and/or application.
In an embodiment, a jacket 110 of a projectile 109 may be manufactured from aluminum, copper, brass, plastic, and or composite. In general, a jacket 110 may encase the projectile 109 and enable the charge dispenser 100 to chamber projectiles 109 which, absent the jacket 110, may be undersized or significantly smaller than the ID of the barrel 101 of the charge dispenser 100. The jacket 110, when encasing the projectile 109, may serve to rifle the projectile 109 to the barrel 101 and ensure that gas expansion around and/or past the projectile 109 is kept to a minimum.
In an embodiment, the jacket 110 may also help to ensure that the projectile 109 is stable in the barrel 101, and when exiting the barrel 101. A smaller diameter projectile 109 may be disposed to tumble inside of the barrel 101, and the use of a jacket 110 around such a projectile 109 may ensure that no such tumbling occurs, keeping the barrel 101 undamaged and enabling reuse of the barrel 101 without requiring any repairs.
In an embodiment, the jacket 110 may be fitted to the caliber of the barrel 101. This allows the charge dispenser 100 to fire, from a single barrel 101, projectiles of various different calibers, any one or more of which may be considerably smaller than the ID of the barrel.
Various embodiments of a jacket 110 with differences in design and composition may be employed, depending on the intended use and application. Some applications may require a sabot which may have physical and operational characteristics and behavior similar to those of the jacket 110. For example, a sabot according to one embodiment may encase a lower portion of a projectile in the same, or a similar, manner as shown for the jacket 110 in
In an embodiment, and with reference to the examples of
One function of the ignitor 111 is to provide a reliable and controlled source of heat, flame, resistance, and or voltage and current, to ignite the propellant, or propellants. In an embodiment, the charge dispenser 100 may be configured to accommodate multiple ignitors 111, and their subcomponents, which may include, for example: (a) ignition element that generates the initial spark or flame; (b) electric mechanism: ignition can be achieved using an electric spark; and/or (c) a bridge wire that may be used to generate a high-temperature spark.
As shown in
With attention now to
In other embodiments, such as the examples of
With reference next to
Turning now to the example of
With reference finally to
Following is a discussion of some example coatings and coating/application processes that may be employed for one embodiment of a charge dispenser. These are provided only by way of example and are not intended to limit the scope of this disclosure, or of any claims, in any way.
Electroless nickel coating, often referred to as EN coating, is a precision plating process used to deposit a layer of nickel-phosphorous alloy onto one or more surfaces of an embodiment of a charge dispenser and/or of a charge dispenser. Unlike electroplating, which requires an external electrical current, electroless nickel plating is an autocatalytic process, that is, electroless nickel plating may be performed without the need for an external power source.
a. Process
Quench Polish Quench (QPQ) is a specialized surface treatment process used to enhance the properties of steel components, primarily focusing on wear resistance, corrosion resistance, and improved aesthetic appearance.
a. Process
Physical Vapor Deposition (PVD) is a vacuum-based thin-film deposition process used to coat surfaces with a variety of functional and decorative materials. In PVD, a solid material is vaporized in a vacuum chamber, and the resulting vapor condenses onto the charge dispensers surface, forming a thin, adherent coating layer.
a. Process
Chemical Vapor Deposition (CVD) is a vacuum-based coating process used to deposit thin films of various materials onto the charge dispensers surfaces. Unlike Physical Vapor Deposition (PVD), where material is physically vaporized and condensed, CVD relies on chemical reactions in a gaseous environment to form a solid coating on the substrate.
a. Process
Atomic Layer Deposition (ALD) is a highly precise and controlled thin-film deposition technique that may be used to create ultra-thin coatings on the charge dispenser. ALD deposits material one atomic or molecular layer at a time, enabling precise control over film thickness and conformality.
a. Process
Plasma Enhanced Chemical Vapor Deposition (PECVD) is a thin-film deposition technique that may be used to create coatings, films, and layers on the charge dispensers surface. PECVD combines elements of chemical vapor deposition (CVD) with plasma generation to enhance the deposition process.
a. Process
The sol-gel process is a versatile and widely used method for producing inorganic and hybrid organic-inorganic materials in the form of gels, powders, films, coatings, and fibers. It involves the transformation of a solution (sol) into a gel-like state through a series of chemical reactions and then further processing to obtain the desired material structure.
a. Process
Chemical Vapor Infiltration (CVI) is an advanced materials processing technique used to produce high-performance composite materials with exceptional properties, especially in terms of mechanical strength, high-temperature resistance, and corrosion resistance.
a. Process
Electrochemical deposition, commonly known as electroplating, is an electrochemical process used to coat the surface of a charge dispenser with a layer of metal or other materials.
a. Process
In an embodiment, the charge dispenser 100 may be machined from solid bar material and the internal geometry of the charge dispenser may be machined using a CNC mill. Following are some example processes that may be used in the manufacture of a charge dispenser according to one embodiment.
One example of such a process may comprise the following operations:
The process begins with the creation of a detailed 3D CAD (Computer-Aided Design) model of the charge dispenser. This model serves as the blueprint for the machining process.
2. CAM programming
The CAD model of the charge dispenser may be imported into CAM (Computer-Aided Manufacturing) software, where a CNC programmer generates toolpaths and instructions for the CNC machine. The programmer may specify the cutting tools, toolpaths, speeds, feeds, and machining parameters.
A raw material block, billet, or bar of suitable material may be securely clamped in the CNC milling machine work holding device, such as a vise or fixture.
The CNC operator or machinist may use the CNC machine controls to align the charge dispenser precisely with the machine's coordinate system to ensure accurate machining.
The required cutting tools, such as end mills, woodruff cutters, and possibly ball mills or custom tooling/cutters for aesthetic features, may be loaded into the CNC machine's tool holders.
The CNC machine software is set to establish a “zero point” or reference point on the charge dispenser, which may serve as the starting point for all machining operations.
The CNC machine starts with roughing operations to remove excess material quickly. Such operations may include:
For the aesthetic features on the outside body of the charge dispenser, the CNC machine may follow specific toolpaths to achieve the desired design. This could involve, but is not limited to, contouring, engraving, or creating intricate patterns using appropriate cutting tools.
To create the bore in the center of the charge dispenser, the barrel and propellant chamber, the CNC machine positions the appropriate cutting tool and precisely follows the programmed toolpath. The bore may be machined to the desired depth and diameter. A pocket may then be opened, or machined out, at the bottom of the bore by controlling the toolpath accordingly.
After rough machining and feature creation, a finishing pass may then be performed using finer tools to achieve a smooth surface finish and precise dimensions.
The charge dispenser may then be inspected using precision measuring instruments to ensure it meets the specified tolerances and quality standards.
Any sharp edges or burrs may be removed, and the charge dispenser may then be cleaned to remove machining residues.
The finished part undergoes a final quality inspection to confirm that it meets all design and quality requirements.
Tooling, or cutters, that may be used to machine the charge dispenser, or some portions and or surfaces of the charge dispenser, may include the following.
In an embodiment, a charge dispenser may be manufactured using a process referred to as additive manufacturing, or 3D printing. An example process for manufacturing an embodiment of a charge dispenser using 3D printing may comprise the following operations.
The process begins with creating a digital 3D model of the charge dispenser that will be printed.
The digital 3D model of the charge dispenser may then be sliced into thin horizontal layers, typically using slicing software. Each layer represents a cross-section of the final charge dispenser.
A suitable alloy such as Inconel, or titanium, may be selected for the final material. Other alloys may include materials such as stainless steel or other alloys containing nickel.
Prepare the build platform or print bed. This may be done by heating the bed to prevent warping of the charge dispenser, and or by applying an adhesive material to the bed to ensure proper adhesion to the charge dispenser as it builds upward from the bed as it prints. A thin layer of metal powder may then be evenly spread over the build platform.
The actual printing process begins, and may comprise any one or more of:
In one embodiment, a high-energy source, such as a laser or electron beam, may precisely be directed according to the sliced data to fuse or sinter the metal powder, creating the first layer of the charge dispenser.
The build platform may then be lowered slightly, and a new layer of metal powder is spread. The energy source selectively fuses the powder to the previous layer, creating the next layer of the charge dispenser.
This process repeats layer by layer until the charge dispenser is completely formed.
After each layer of the charge dispenser is printed, it is allowed to cool and solidify. The charge dispenser gradually takes shape as additional layers are added.
While the charge dispenser may appear complete after printing, it may require post-processing to meet final specifications and improve its properties. Common post-processing steps may include:
If supports are required during printing to stabilize overhanging features, they may need to be removed.
The printed charge dispenser may undergo a final inspection to ensure it meets all quality and dimensional requirements.
The charge dispenser may require additional processes such as coating, plating, or assembly.
When the propellant, and or energetic, located in the propellant chamber of the charge dispenser is ignited, a considerable amount of heat and pressure may be generated inside the chamber and within some areas of the charge dispensers barrel. The material that the charge dispenser may be manufactured from may thus require certain properties such has high minimum yield strengths, high min tensile strengths, low percentage of elongation, and high toughness. These properties may help to ensure that the charge dispenser survives the firing process without yielding and or experiencing permanent, or plastic, deformation. This may enable the charge dispenser to be reloaded and reused multiple times.
The alloys and the chemical composition of the alloys, or materials that may be used to manufacture a charge dispenser, may comprise any one or more of the materials set forth below.
Other alloys, or materials that may be used to manufacture a charge dispenser, may also consist of the following elements:
Following are some further example embodiments. These are presented only by way of example and are not intended to limit the scope of this disclosure, or the scope of any claims, in any way.
Embodiment 1. An apparatus for use in a downhole process, comprising: a body configured to be removably received in a corresponding recess of a perforation gun system; a propellant chamber defined in the body; a projectile chamber defined in the body and positioned in the body above, and in communication with, the propellant chamber; a barrel defined in the body and positioned in the body above, and in communication with, the projectile chamber; and a muzzle defined in the body and positioned in the body above, and in communication with, the barrel.
Embodiment 2. The apparatus as recited in any preceding embodiment, wherein the body defines an ignition jack that communicates with the projectile chamber.
Embodiment 3. The apparatus as recited in any preceding embodiment, wherein an inside diameter of the projectile chamber corresponds to a caliber of an associated projectile.
Embodiment 4. The apparatus as recited in any preceding embodiment, wherein the body has a generally cylindrical configuration.
Embodiment 5. The apparatus as recited in any preceding embodiment, wherein the body is made of a single piece of metal.
Embodiment 6. The apparatus as recited in any preceding embodiment, wherein the propellant chamber comprises a nozzle that opens into the projectile chamber.
Embodiment 7. The apparatus as recited in any preceding embodiment, wherein the barrel is rifled.
Embodiment 8. The apparatus as recited in any preceding embodiment, wherein an inside diameter of the barrel is smaller than an inside diameter of the propellant chamber.
Embodiment 9. The apparatus as recited in any preceding embodiment, wherein structural integrity of the body is retained after a projectile has been fired from the apparatus.
Embodiment 10. The apparatus as recited in any preceding embodiment, wherein the projectile chamber is configured to accommodate projectiles of different respective calibers.
Embodiment 11. The apparatus as recited in any preceding embodiment, wherein the apparatus is configured to accommodate a projectile and an ignition conductor that interfaces with the projectile from outside the body.
Embodiment 12. The apparatus as recited in any preceding embodiment, wherein the body is configured to withstand internal pressures up to 100,000 psi when firing a projectile, while retaining its structural integrity during and after the firing.
Embodiment 13. The apparatus as recited in any preceding embodiment, wherein a length of the body is in a range of 1.5″ to 4″.
Embodiment 14. The apparatus as recited in any preceding embodiment, wherein after a projectile has been fired from the apparatus, the apparatus is reusable to fire another projectile.
Embodiment 15. The apparatus as recited in any preceding embodiment, wherein the body defines a nozzle that is positioned between, and communicates with, the propellant chamber and the projectile chamber.
Embodiment 16. The apparatus as recited in embodiment 15, wherein the nozzle has a first end and a second end, and the first end has a larger diameter than a diameter of the second end, and the first end is adjacent to the propellant chamber, and the second end is adjacent to the projectile chamber.
Embodiment 17. An apparatus for use in a downhole process, comprising: a body configured to be received in a corresponding recess of a perforation gun system; and a projectile positioned in a projectile chamber that is defined within the body.
Embodiment 18. The apparatus as recited in embodiment 17, wherein the body defines a propellant chamber below, and in communication with, the projectile chamber, and the propellant chamber holds one or more propellants.
Embodiment 19. The apparatus as recited in embodiment 18, wherein the one or more propellants comprise two propellants that are layered one on top of the other.
Embodiment 20. The apparatus as recited in embodiment 18, wherein one of the one or more propellants is in solid form.
Embodiment 21. The apparatus as recited in embodiment 18, wherein one of the one or more propellants is in powder form, and/or a granular form.
Embodiment 22. The apparatus as recited in embodiment 18, wherein the one or more propellants comprise a first propellant and a second propellant, and the first propellant has a faster burn rate than a burn rate of the second propellant, and, in operation, the faster burn rate initially causes the projectile to accelerate, and the burn rate of the second propellant sustains a velocity of the projectile as the projectile passes through a casing, cement, and formation.
Embodiment 23. The apparatus as recited in embodiment 18, wherein the body defines a propellant chamber comprising a nozzle that opens into the projectile chamber.
Embodiment 24. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the body defines an ignition jack that communicates with the projectile chamber, and the apparatus comprises an ignition conductor that passes through the projectile, and a first end of the ignition conductor is electrically connected to an ignitor positioned in a propellant chamber that is located below the projectile chamber, and a second end of the ignition conductor is positioned in the ignition jack.
Embodiment 25. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the body defines an ignition jack that communicates with the projectile chamber, and the apparatus comprises an ignition conductor that is electrically connected to a tip of the projectile and is also electrically connected to an ignitor positioned in a propellant chamber that is located below the projectile chamber, and the ignition conductor, the projectile, and the ignitor, together, form a portion of an electrical circuit.
Embodiment 26. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the body defines a barrel that communicates with the projectile chamber.
Embodiment 27. The apparatus as recited in embodiment 25, wherein the barrel is rifled.
Embodiment 28. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the projectile comprises a jacket.
Embodiment 29. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the projectile comprises an electrically insulative coating.
Embodiment 30. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the projectile comprises a coating.
Embodiment 31. The apparatus as recited in any preceding embodiment beginning at embodiment 17, wherein the projectile comprises a sabot.
Embodiment 32. The apparatus as recited in embodiment 31, wherein the sabot is metal, plastic, or composite.
Embodiment 33. The apparatus as recited in embodiment 31, wherein the projectile is partly received in the sabot, and the sabot comprises an element of an electrical circuit that includes the sabot, the projectile, and an ignitor located in a propellant chamber below the projectile chamber
Embodiment 34. The apparatus as recited in any preceding embodiment beginning at embodiment 17, further comprising a perforating gun configured to removably receive the body.
The described embodiments are to be considered in all respects only as illustrative and not restrictive. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
| Number | Date | Country | |
|---|---|---|---|
| 63597166 | Nov 2023 | US |
