Imported: 10 Mar '17 | Published: 27 Nov '08
USPTO - Utility Patents
The specification and drawing figures describe and show an apparatus for penetrating a target and achieving beyond-penetration results. The apparatus includes a liner. The liner includes at least one liner member formed of a penetrating material and one liner member formed of a reactive material, and may include at least one liner member formed of neither a penetrating nor reactive material. The liner member is positioned in a housing. The housing includes an explosive and means for detonating the explosive.
The U. S. Government has a paid-up license in the apparatus for penetrating a target and achieving beyond-penetration results, and the right in limited circumstances to require the patent owner to license others on reasonable terms, as provided by Contract Nos. N68936-03-C-0018 arid N68936-04-C-0001 awarded by the U.S. Department of the Navy.
The apparatus and method disclosed and claimed in this document pertains generally to explosive devices that not only penetrate a target with at least one penetrating stream of penetrating materials, but also deliver at least a second penetrating stream of reactive materials for achieving beyond-penetration results. More particularly, the new and useful apparatus for penetrating a target and achieving beyond-penetration results that is disclosed and claimed in this document pertains to a shaped charge liner that, on detonation, collapses into streams of material and slugs of material that both penetrate a target and discharges beyond the target at least one reactive material that causes and induces pressurization, impulses, heat and other effects beyond the impact point of the target. The apparatus is particularly, but not exclusively, useful in munitions and in hydrocarbon recovery from oil and gas wells.
High penetration is an art well developed for shaped charges. Achieving beyond-penetration-effects can both augment lethality in weapons and, in another embodiment, provide for enhanced oil and gas recovery. Current reactive metal-lined shaped charge devices have poor penetration properties because the reactive materials thus far chosen for use in making shaped charge liners suffer inferior material properties for forming penetrating streams, resulting in disappointing implementation. Attempts to improve shaped charge weapon lethality using follow-through of reactive materials also has failed to deliver substantial internal effects in part because the slug or slugs that are formed and ejected following explosive collapse of a shaped charge liner block passage of a reactive stream of reactive material through an entry hole formed in the target.
No one has suggested a structure either in the industry literature or in patents for a shaped charge liner that combines and connects metal and non-metal materials for a specifically contemplated mission that requires both penetration and post-penetration reactive results and effects. The absence of such an apparatus probably results from the absence of any requirement for such an apparatus by organizations currently funding research and development in the field. In addition, teachings in the industry suggest that coherent material stream formations and predictable sequences of coherent streams of material would not be possible.
Reactive metals such as aluminum, zirconium, magnesium and similar metals have different dynamic properties than shaped charges formed with penetrating materials composed of copper, molybdenum, and similar metals. Teachings in the art assume that use of those materials in a construct of the materials assembled adjacent to one another in a shaped charge liner would likely result in failure, and would not produce a jet or stream of the materials described in this document (in this document, individually a stream and collectively, stream of materials).
The inventor named in this document reasoned and then proved by testing that while a metallurgical bond would facilitate interface conditions to achieve stream coherency during collapse of a liner composed of dissimilar metals, experiments also indicated that formation of a stream of materials following detonation of a shaped charge and the consequent collapse of the shaped charge liner does not depend necessarily on a method of connecting the adjacent materials used to make the shaped charge liner.
Another reason that likely explains the absence of an apparatus for penetrating a target and achieving beyond-penetration results arises from the feet that penetration of a target has been the primary goal or object of shaped charge warheads. Shaped charge engineers, therefore, have focused on penetrating a target, not on both penetrating a target and achieving beyond-penetration results. Accordingly, there has been little motivation to extend the art beyond achieving penetration of a target.
However, a need exists in the industry for a new, useful apparatus in the form of a shaped charge for both penetrating a target and for achieving beyond-penetration results.
The apparatus for penetrating a target and achieving beyond-penetration results as described and claimed in this document provides a target-penetrating apparatus made of energetic materials in the form, in at least one embodiment, of a shaped charge that generates volume encompassing defects and results beyond the point of impact on the target without sacrificing penetration capabilities of the apparatus.
In at least one other embodiment of the apparatus for penetrating a target and achieving beyond-penetration results (the hydrocarbon recovery embodiment), the apparatus is capable of perforating cemented well bore cases and geologic formations. Thereafter a material stream subsequently pressurizes perforations to increase the length and number of fractures, while opening the fractures to enhanced hydrocarbon recovery. In the hydrocarbon recovery embodiment of the apparatus, it should be understood that after an oil and/or gas well is drilled, an act of completion is undertaken in which the well is perforated. Perforations provide a. means by which the well bore is interconnected to the geologic formation. An additional process may be undertaken called fracturing. Fracturing is done quasi-statically or dynamically. During the fracturing process the well bore is pressurized. In addition, fractures are initiated in the geologic formations, driven into the geologic formations, and interconnected. Interconnecting the fractured materials can be achieved by the apparatus for penetrating a target and achieving beyond-penetration results as shown and claimed in this document.
Because of the unique combination of both a penetrating material and a reactive material, the liner included in the apparatus disclosed and claimed in this document will collapse following detonation and explosion. The collapsing of the liner will result in formation of a penetrating stream of materials formed from penetrating material that penetrates a target. The collapsing of the liner also will result in a reactive stream of materials composed of reactive materials that follow the penetrating stream through the target past the impact point. The reactive stream of materials initiates energetic effects beyond the point of impact. The inventor named in this document has confirmed what no one else has confirmed, a penetrating stream of penetrating material is inadequate to achieve beyond-penetration results. What is needed is the addition of a reactive stream formed of a reactive material for achieving beyond-penetration results.
An apparatus for penetrating a target and achieving beyond-penetration results includes a liner. The liner includes at least one liner member formed of a penetrating material. The liner also includes at least one liner member formed of a reactive material that is connected to the at least one liner member formed of a penetrating material. The liner may also include a liner member formed neither of a penetrating material nor a reactive material. The liner members may be connected by any of a variety of connecting options including monolithically, by explosive welding, by diffusion bonding, mechanically, by an adhesive, friction welding, inertia welding, electron beam welding, chemical bonding, and any other means for connecting liner members.
An apparatus for penetrating a target and achieving beyond-penetration results also includes a housing. The housing is adapted to contain the substantially conical liner prior to detonation and explosion. When installed in the housing, the liner defines an opening in one end of the housing. A penetrating stream of the penetrating material for penetrating a target (in this document, a penetrating stream), and a reactive stream of the reactive material for achieving the beyond-penetration results (in this document, a reactive stream), is discharged through the opening formed in the liner. A cavity also is formed between the liner and the housing. The cavity is adapted to hold an explosive for detonation of the apparatus.
An apparatus for penetrating a target and achieving beyond-penetration results also includes means for detonating the explosive to collapse the liner and to discharge a penetrating stream and a reactive stream through and past a target. At least one means for detonating the explosive is an initiator system. In addition, a standoff may be provided to provide a known or desired distance between the apparatus and target. The standoff helps directs detonation and explosive collapse of the liner.
To better appreciate the disclosure and claims provided in this document, the following terms have the following meanings:
The term housing means at least an axially symmetric body that may have physical walls to support the explosive charge. The housing for the shaped charge is an abstract space to which the cavity extends.
The term formed monolithically means a manufacturing process whereby the item is cast or molded resulting in a final product such that a single structure is an undifferentiated whole.
The term initiation system means a device that serves to align explosive components used to initiate detonation in the explosive contained in the cavity surrounding the shaped charge liner. Components may include items such as a booster, a detonator, fusing and sensor components typically found in shaped charge devices.
The term material or materials means either or both metal and non-metal substances.
The term penetrating material means at least a material having the characteristics of being ductile, high-density materials that may also have the property of low melt energy. Oxygen-free high-conductivity copper is one example. Other non-exclusive examples include tantalum, lead, silver, gold, aluminum, molybdenum, nickel, and zinc. Penetrating materials also include powder metals, gradient of powder metals, and gradient blends of metals and alloys.
The term reactive materials means at least a material having the characteristics of having substantial reaction spontaneity, feasibility, and reasonable activation energy. Reactive materials also reduce to small particles (comminute) when subjected to abrasion and similar forces that pulverize reactive materials. Other non-exclusive examples of reactive materials are aluminum, titanium, zirconium, some of their respective alloys, some alloys of tantalum/tungsten at suitably high strain and strain rates typically achieved during explosive collapse of shaped charge liners.
The term detonation and explosive collapse and related terms means an action induced in a shaped charge device whereby an explosive detonation wave interacts with the liner to compress it, thus forming (i) one or more streams of material originating from the interior of the liner (the air side), and (ii) one or more pieces, chunks, or slugs of material (in this document, slugs) formed from the exterior surface of a liner (the explosive side).
The term explosively welding means a solid state bonding process that forms a metallurgical, electron-sharing bond between adjacent metals.
The term diffusion bonding means a specific manner of welding causing an interdiffusion of atoms in the joined materials. Formation of bonds is at the atomic level. Mating surfaces are brought together at high temperatures for a sustained period of time. The process is usually conducted in a partial vacuum.
The term mechanically connected means an interlocking joint between two materials, such as, for example, a dovetail joint, or a tenon and mortise.
The term adhesive means a substance placed between two materials that, after curing, form a molecular bond and mechanically connects the components.
The term beyond-penetration result means thermo-chemical and kinetic events occurring in the immediate area of a material stream impact beyond an entry hole through a target In a weapons application, beyond-penetration effects may be referred to as behind-armor-effects. At least three beyond-penetration-effects are possible. Internal blast is characterized by pressurization of a volume, shock waves, and sustained pressure, impulse effects include phenomena such as entrainment of debris in blast waves that result in multiple ricochets of material. Combustion effects include heat flux, augmented sustained pressurization, and sustained impulse. In a hydrocarbon recovery application beyond-penetration-effects have some similar effects as in weapons applications, but include, for example, well bore and perforation pressurization resulting from the reaction of reactive liner materials.
The term mission means the application or objective sought to be accomplished by a user of the apparatus and methods described and claimed in this document, such as a specific beyond-penetration result sought to be accomplished.
The term order means the arrangement and grouping, both as to sequence and number, of the material or materials used in the assembly of a liner for a given mission.
The term stream means ejecta from detonation and explosive collapse of a shaped charge device. A stream may include slower moving aft components of the collapsed liner called a slug or slugs in this document. A stream is formed from the interior of the liner (as indicated, the air side). A slug is formed from the exterior of the liner (as indicated, the explosive side). The leading end of a stream is moving at approximately the velocity of detonation of the explosive. The trailing end of a stream may move at approximately one-quarter the speed of the leading end; a slug may move at approximately one-sixteenth the speed.
The term standoff means a device that defines a distance between the shaped charge device and the target. As shown in this document, the standoff is a device that defines a distance, and may be mountable on the housing A standoff may also be a combination of a sensor and a fuse (not shown) that also activates when a desired distance from a target, but may or may not be mountable on the housing. The standoff may be necessary to provide a volume or void into which a stream or streams of material may form and stretch or extend to an optimal length without perturbation before impacting or penetrating a target.
The term comminute or comminution means at least a size reduction typically resulting from operations such as compression, impact, attrition, nibbing, cutting, grating, shearing, filing, or cutting.
It will become apparent to one skilled in the art that the claimed subject matter as a whole, including the structure of the apparatus, and the cooperation of the elements of the apparatus, combine to result in a number of unexpected advantages and utilities. The structure and co-operation of structure of the apparatus for penetrating a target and achieving beyond-penetration results will become apparent to those skilled in the art when read in conjunction with the following description, drawing figures, and appended claims.
The foregoing has outlined broadly the more important features of the apparatus claimed, and includes useful definitions, to better understand the detailed description that follows and to better understand the contributions to the art. The apparatus for penetrating a target and achieving beyond-penetration results is not limited in application to the details of construction, and to the arrangements of the components, provided in the following description or drawing figures, but is capable of other embodiments, and of being practiced and carried out in various ways. The phraseology and terminology employed in this disclosure are for purpose of description, and therefore should not be regarded as limiting. As those skilled in the art will appreciate, the conception on which this disclosure is based readily may be used as a basis for designing other structures, methods, and systems. The claims, therefore, include equivalent constructions. Further, the abstract associated with this disclosure is intended neither to define the apparatus for penetrating a target and achieving beyond-penetration results, which is measured by the claims, nor intended to limit the scope of the claims.
The novel features of the apparatus for penetrating a target and achieving beyond-penetration results are best understood from the accompanying drawing, considered in connection with the accompanying description of the drawing, in which similar reference characters refer to similar parts, and in which:
To the extent that subscripts to the numerical designations include the lower case letter n, as in a-n, the letter n is intended to express a number of repetitions of the element designated by the numerical reference and subscripts,
As shown in FIGS. 1-9, an apparatus for penetrating a target and achieving beyond-penetration results 10 is provided that in the broadest context includes a shaped charge liner (liner) 12. As shown in FIGS. 2-6, in one embodiment the liner is substantially conical, but the cross-sectional shape of the liner 12 is not a limitation of liner 12. The liner 12 includes at least one liner member 14a formed of a penetrating material 16. The liner 12 also includes at least one liner member 14b formed of a reactive material 18. The at least one liner member 14a formed of a penetrating material 16, and the at least one liner member 14b formed of a reactive material 18, as well as any liner member 14n not formed of either a penetrating material 16 or of a reactive material 18, are connected to form the liner 12.
The liner members 14a-n may be connected in any of a variety of ways, including monolithically, by explosive welding, by diffusion bonding, mechanically, by adhesion using an adhesive, friction welding, inertial welding, electron beam welding, chemical bonding, or other means for connecting the liner members 14a-n.
An apparatus for penetrating a target and achieving beyond-penetration results 10 also includes a housing 20. The housing 20 is adapted to contain the liner 12. When installed in the housing 20, the liner 12 defines an opening 22 in one end of the housing 20. A penetrating stream 24 of the penetrating material 16 (penetrating stream) for penetrating a target 26 and a reactive stream 28 of the reactive material 18 (reactive stream) for achieving the beyond-penetration results are discharged through the opening 22. A cavity 30 also is formed between the liner 12 and the housing 20. The cavity 30 is adapted to hold an explosive 32 for the detonation of the apparatus 10 and to induce or cause collapse of liner 12.
An apparatus for penetrating a target and achieving beyond-penetration results 10 also includes a means 34 for detonating the explosive 32 to discharge the penetrating stream 24 and the reactive stream 28, such as an initiation system 34. In addition, a standoff 36 may be provided. The standoff 36 is mountable on the housing 20 to provide a volume into which the penetrating stream 24 and reactive stream 28 may form and stretch or extend to an optimal length without perturbation before impacting or penetrating a target 26.
More specifically, in the embodiment illustrated by cross-reference between FIGS. 1-2, an apparatus for penetrating a target and achieving beyond-penetration results 10 is provided by a shaped charge device 38 that shows a penetrating stream 24 that impacts an impact point 40 on a target 26, forms an entry hole 42 through the target, and is followed by a reactive stream 28. The reactive stream 28, as shown in FIGS. 1-2, initiates and causes energetic effects beyond both the impact point 40 and the entry hole 42.
In addition, as shown by cross-reference between FIGS. 1-2 and 7-9, a portion of the liner 12 that is collapsed following detonation and explosion may contribute to beyond-penetration results. As shown, following detonation of the explosive 32 in the cavity 30, and the formation of a penetrating stream 24 and a reactive stream 28, at least one slug 44 of material from a liner member 14a-n may be discharged toward the target 26. A slug 44 may be formed of reactive material 18. A slug 44 also may be formed of one or more other materials from which a liner member 14a-n is made.
Generally, a slug 44 moves more slowly toward the target 26 than the penetrating stream 24 and follows behind or trails the penetrating stream 24 and any reactive stream 28. As indicated, the penetrating stream 24 impacts the impact point 40 of the target 26, continues through the target 26, thus forming an entry hole 42 through the target 26. The entry hole 42 tends to be jagged, with one or more edges 46a-n that macerate or comminute the slug 44 into particles 48 that continue into and past the target in a materials stream, preferably a reactive stream 28. The particles 48 of the reactive stream 28 contribute to beyond-penetration results desired in a particular application of the apparatus for penetrating a target and achieving beyond-penetration results 10.
Moreover, the size reduction of the particles 48 provides for un-oxidized, high surface area particles to enter an environment preconditioned to combust other materials efficiently. The preconditioning event is the injection of the reactive materials 18 in the form of a reactive stream 18, and its exothermic reaction. Experimentation has disclosed that at least the following materials are appropriate for utilizing selected parts of the liner as follow-through components which comminute Into finely divided particles 48 that contribute to the beyond-penetration effects and results, whether in a weapons application, or in a hydrocarbon recovery application of the apparatus for penetrating a target, and achieving beyond-penetration results 10.
The at least one liner member 14a formed of a penetrating material 16, and the at least one liner member 14b formed of a reactive material 18 connected to the at least one liner member 14a formed of a penetrating material 16, as perhaps best shown in FIGS. 2-5, are made from materials selected on the basis of physical, chemical, and structural properties, both static and dynamic. The combination of materials selected to form an apparatus 10 depends on a specific application for the apparatus 10. Thus, manufacture or fabrication of the liner 12 may be from a single piece of material or may be from multiple pieces assembled.
Referring to FIGS. 2-5, the liner 12 is shown with two liner members 14a-b in FIG. 3, at least one liner member 14a formed of a penetrating material 24, and at least one liner member 14b formed of a reactive material 18. However, one or more liner member 14a-n may be connected in any number of combinations and permutations depending on the mission to be accomplished as shown in FIGS. 4-5. The cross-sectional geometry of the shaped charge liner as shown in FIGS. 1-5 is conical. However, the cross-sectional shape or shapes of the liner 12 is not a limitation of the apparatus 10, and any number of shapes for the liner 12 may be employed by those skilled in the art. In addition, at least one liner member 14n formed of neither a penetrating material 16 nor of a reactive material 18 may by included in the liner 12 as shown in FIG. 5.
The at least one liner member 14a-n formed of a penetrating material 16, the at least one liner member formed of a reactive material 18, and the at least one liner member formed of neither a penetrating material nor of a reactive material are collectively referred to in this document as liner members 14a-n. The liner members 14a-n are in collective connection to form liner 12. The terra collective connection as used in this document means that a liner member 14a-n need only touch or be in contact with another liner member 14a-n that is included in a liner 12. Thus, although FIG. 3 shows a machined over-lapping tongue joint 50 for connecting liner member 14a to liner member 14b, no bond or bonding is necessary to securely connect liner members 14a-n.
As indicated, and as shown by cross-reference between FIGS. 2-5, liner member 14a is formed of a penetrating material 16. The penetrating material 16 is a ductile, high-density metal. In a preferred embodiment, the penetrating material 16 is oxygen-free high-conductivity copper. However, a number of other materials may be used as the penetrating material 16, including at least tantalum, lead, silver, gold, aluminum, as well as non-metals.
As also shown by cross-reference between FIGS. 2-5, liner member 14b is formed of a reactive material 18, and is connected to the at least one liner member 14a formed of a penetrating material 18 is shown. As shown, the reactive material 18 is selected from a group of reactive materials that has substantial reaction spontaneity, feasibility, and reasonable activation energy for the particular application intended for the apparatus 10.
The reactive material 18 also has property characteristics that, upon detonation and explosion of the explosive 32, allows the reactive material 18 to be reduced into smaller particles 48 by actions typically associated with comminution, such as shearing, attrition, impact, pulverization, maceration, filing and cutting. Preferably, comminution of the reactive material 18 used to form the at least one liner member 14b formed of reactive material 18 will shear into small flakes with comparatively high surface area. Thus, reactive material 18 preferably includes materials that fail, under comminution action, by adiabatic shear. Accordingly, the reactive materials 18 may include at least aluminum, titanium, zirconium, alloys of those metals, some alloys of tantalum combined with tungsten, and depleted uranium. These metals, among others, provide for varying reaction spontaneity, feasibility and activation energy.
As also shown in FIGS. 2 and 4-5, the trailing reactive stream 28 of the reactive material 18 follows the leading penetrating stream 24 of the penetrating material 16 through the entry hole 42 formed through the target 26 by the leading penetrating stream 24. In a weapons application, the beyond-penetration results would be, for example, to destroy or disable munitions, interior surfaces, fuel storage and similar secondary targets. In an oil and gas well perforating charge application, the penetrating stream 24 substantially penetrates a geologic formation, as shown by cross-reference to FIGS. 6-9. The trailing reactive stream 28 provides additional penetration. The reactive stream 28 initiates an energetic event, which increases the pressure and generates heat in a confined space beyond the preliminary target, whether an armored or fortified military target, or an oil and gas well geologic perforation.
The energetic event is an environmental preparation for follow-through material generated by a stream of particles 48 adapted to sustain additional beyond-penetration results following detonation of the explosive 32. As a result, in a weapons application as shown in FIGS. 1-5, lethality past the impact point at the target 26 is increased. As shown in FIGS. 6-9, in an oil and gas well perforating application, fractures 52 initiate and propagate in geologic formations 54 from the geologic perforations 56, interconnect with natural fractures (not shown), while some reaction (combustion) products and other materials open the fractures 52 and other reaction materials maintain such open fractures 52 in an open configuration, thus providing for enhanced hydrocarbon recovery.
FIGS. 4-5 and 6-9 show alternative embodiments of the apparatus for penetrating a target and achieving beyond-penetrating results 10 . As shown in FIGS. 4-5, liner 12 is formed of more than two liner members 14a-n. As shown, by way of example, at least one liner member 14c formed of a penetrating material 16 is provided. In addition, a liner member 14d and 14d formed of a reactive material 18 is connected to the at least one liner member 14c formed of a penetrating material 16.
To assist in an understanding of the unique contributions made to the art by the apparatus for penetrating a target and achieving beyond-penetration results 10, FIGS. 4-5 include correlative cross-hatching and legends. Thus, the cross-hatching of penetrating material 14c in liner 12 correlates to the cross-hatching of slug 44. All three liner members are collectively connected. The choice of materials 16,18 for the respective liner members 14a-n is dictated by the intended mission or application of the apparatus 10 in an operative environment. For example, the combination and permutation of liner members 14a-n may depend on or be dictated by thermo-chemical requirements such as increasing the combustion and/or reaction spontaneity, or reducing activation energy required to initiate and sustain beyond-penetration results.
As shown in cross-reference between FIGS. 6-9, an apparatus for penetrating a target and achieving beyond-penetration results 10 is shown in an operative environment for use in an oil and gas well perforating charge application. As shown, a shaped charge liner 12n composed of at least one liner member 14a formed of a penetrating material 16, and at least one liner member 14b formed of a reactive material 18, is oriented for discharge against a well casing 58. In some instances, a well casing 58 may not be present. In such instances, the shaped charge liner 12n may be oriented for penetration of concrete 60 adjacent to a geologic formation 54. In the absence of either a well casing 58 or a concrete liner 60, the shaped charge liner 12n may be oriented for penetration of the geologic formation 54.
FIG. 7 shows particles 48 of reactive material 18 penetrating the geologic formation 54 following penetration of the target 26. The beyond-penetration results achieved in this embodiment are shown in FIGS. 8-9. Reaction of the comminuted reactive materials takes place (represented diagrammatically by the letter A on FIG. 8), pressurizing the perforation in initiation of a fracture 52 in the geologic perforation. FIG. 9 shows that as a result of the beyond-penetration actions, combustion products from the reaction form relatively hard materials, preferably of aluminum oxide if an aluminum reactive material is used. The fracture 52 is expanded or opened, allowing enhanced hydrocarbon recovery.
The apparatus for penetrating a target and achieving beyond-penetration results shown in drawing FIGS. 1 through 9 includes a number of embodiments, but the embodiments are not intended to be exclusive, merely illustrative of the disclosed but non-exclusive embodiments.
Claim elements and steps in this document have been numbered solely as an aid in readability and understanding. Claim elements and steps have been numbered solely as an aid in readability and understanding. The numbering is not intended to, and should not be considered as intending to, indicate the ordering of elements and steps in the claims. Means-plus-function clauses in the claims are intended to cover the structures described as performing the recited function that include not only structural equivalents, but also equivalent structures. Thus, although a nail and screw may not be structural equivalents, in the environment of the subject matter of this document a nail and a screw may be equivalent structures.