Patent Application
20200217629
A shaped charge liner including a plurality of metal powders having a high purity metal is generally described. More specifically, a shaped charge having a shaped charge liner including at least one high purity level metal having a purity level of at least about 99.5% is described.
As part of a well completion process, cased-holes/wellbores are perforated to allow fluid or gas from rock formations (reservoir zones) to flow into the wellbore. Perforating gun string assemblies are conveyed into vertical, deviated or horizontal wellbores, which may include cemented-in casing pipes and other tubulars, by slickline, wireline or tubing conveyance perforating (TCP) mechanisms, and the perforating guns are fired to create openings/perforations in the casings, as well as in surrounding formation zones. Such formation zones may include subterranean oil and gas shale formations, sandstone formations, and/or carbonate formations.
Often, shaped charges are used to form the perforations within the wellbore. These shaped charges serve to focus ballistic energy onto a target, thereby producing a round perforation hole (in the case of conical shaped charges) or a slot-shaped/linear perforation (in the case of slot shaped charges) in, for example, a steel casing pipe or tubing, a cement sheath and/or a surrounding geological formation. In order to make these perforations, shaped charges typically include an explosive/energetic material positioned in a cavity of a housing (i.e., a shaped charge case), with or without a liner positioned therein. It should be recognized that the case, casing or housing of the shaped charge is distinguished from the casing of the wellbore, which is placed in the wellbore after the drilling process and may be cemented in place in order to stabilize the borehole prior to perforating the surrounding formations. Often, the explosive materials positioned in the cavity of the shaped charge case are selected so that they have a high detonation velocity and pressure.
The shaped charges are typically initiated shortly after being placed within the wellbore to prevent prolonged exposure to the high temperature of the wellbore. When initiated, the explosive material housed within the shaped charge detonates and creates a detonation wave, which will generally cause the liner to collapse and be ejected/expelled from the shaped charge, thereby producing a forward moving perforating jet that moves at a high velocity. The perforating jet travels through an open end of the shaped charge case which houses the explosive charge and serves to pierce/penetrate the perforating gun body, casing pipe or tubular and surrounding cement layer to form a cylindrical/conical (perforation) tunnel in the surrounding target geological formation. The tunnel facilitates the flow of and/or the extraction of fluids (oil/gas) from the formation.
Typically, the liners include various constituents, such as powdered metallic and non-metallic materials and/or powdered metal alloys, and binders, selected to generate a high-energy output or jet velocity upon detonation. Imperfections in the liner morphology and/or impurities in the various constituents of the liner have been found to impair the performance of the liner and the resultant perforation tunnel. A general example of such liners 1 is illustrated in
In view of the disadvantages associated with currently available methods and devices for wellbore perforating, there is a need for a shaped charge liner that forms a uniform jet upon detonation of a shaped charge. The present disclosure addresses this need, and also provides a shaped charge that does not have to be isolated from the high temperatures of the wellbore, and a method of perforating a wellbore that enhances the resultant flow of fluids from the formation.
According to an aspect, the present embodiments may be associated with a shaped charge liner. Such shaped charge liners may create ideal perforation for stimulation of the flow of oil/gas from wellbores.
The shaped charge liner includes a plurality of metal powders. The plurality of metal powders include at least one high purity level metal, which is selected from the group consisting of copper, tungsten, nickel, titanium, aluminum, lead, tantalum and molybdenum. The high purity level metal has a purity level of at least about 99.5%. The metal powders are compressed to form the shaped charge liner. When the shaped charge liner is heated, it has a porosity level of less than about 20 volume %. Such shaped charge liners are able to maintain their mechanical integrity at temperatures of at least about 250° C.
Further embodiments of the disclosure are associated with a shaped charge including a case, an explosive load, and a shaped charge liner. The case includes a closed end, an open end opposite the closed end, and a hollow interior or cavity. The explosive load is disposed in the hollow interior, and the shaped charge liner is disposed on the explosive load. The shaped charge liner may be configured substantially as described hereinabove. The shaped charges including the aforementioned liners may be heated to the temperature of a wellbore so that the shaped charge liner is able to form a rapidly elongating perforation jet, which reduces particulation (i.e., break-up or separation) of the perforating jet upon detonation of the shaped charge into the wellbore.
More specifically, embodiments of the disclosure may further be associated with a method of perforating a wellbore using a shaped charge. The method includes installing at least one shaped charge within a shaped charge carrier. The shaped charge includes a case, an explosive load, and a shaped charge liner, which may be configured substantially as described hereinabove. The shaped charge carrier and the shaped charge installed therein, is thereafter positioned into the wellbore. The shaped charge and the shaped charge liner housed therein is heated, or allowed to be, by the wellbore temperature. According to an aspect, when the shaped charge liner is heated to a temperature of up to about 250° C., the packing density of the particles increases so that the liner has a porosity of less than about 20 volume %. The heated liner is not only able to maintain its mechanical integrity at a temperature of at least about 250° C., but also becomes malleable when heated. In addition, when the shaped charge is detonated, the shaped charge liner is able to form a perforating jet that is coherent and rapidly elongating, which reduces particulation of the perforating jet and enhances stimulation of the flow of oil/gas from wellbore.
A more particular description will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments thereof and are not therefore to be considered to be limiting of its scope, exemplary embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
Various features, aspects, and advantages of the embodiments will become more apparent from the following detailed description, along with the accompanying figures in which like numerals represent like components throughout the figures and text. The various described features are not necessarily drawn to scale, but are drawn to emphasize specific features relevant to some embodiments.
The headings used herein are for organizational purposes only and are not meant to limit the scope of the description or the claims. To facilitate understanding, reference numerals have been used, where possible, to designate like elements common to the figures.
For purpose of illustrating features of the embodiments, embodiments will now be introduced and referenced throughout the disclosure. Those skilled in the art will recognize that these examples are illustrative and not limiting, and are provided for purely explanatory purposes.
In the illustrative examples and as seen in
The liner 10 may have a variety of shapes, including conical shaped (e.g., liner 10′) as shown in
The shaped charge liner 10 generally has an apex portion 22 and a perimeter that forms a skirted portion 24. The shaped charge liner 10 may generally have a thickness T/T1/T2 (generally “T”) ranging from between about 0.5 mm to about 5.0 mm, as measured along its length L. As illustrated in
Additionally, the composition of the illustrative liners 10, as seen for instance in
According to an aspect, the shaped charge liner 10 generally includes various powdered/pulverized metallic and/or non-metallic powdered metals, alloys and binders. Such shaped liners are, for instance, described in U.S. Pat. Nos. 3,235,005, 3,675,575, 5,567,906, 8,075,715, 8,220,394, 8,544,563 and German Patent Application Publication No. DE102005059934, each of which is incorporated herein by its entirety.
The shaped charge liner 10 includes a plurality of metal powders 12. The plurality of metal powders 12 is compressed to form the shaped charge liner 10. The metal powders 12 may include lead, copper, aluminum, nickel, tungsten, titanium, molybdenum, aluminum-bronze, manganese-bronze, or any other metal powder or alloys that have a melting temperature of above 320° C., as would be understood by one of ordinary skill in the art.
The plurality of metal powders 12 includes at least one high purity level metal 14 having a purity level of at least about 99.5%. As such, the high purity level metal 14 has less than about 0.5% of any other type of identifiable metal (i.e., metal contaminant) within any given sample.
The at least one high purity level metal 14 is present in an amount up to about 95% of a total weight of the plurality of metal powders 12. Various high purity level metals 14 may be compressed to form the liner 10. According to an aspect, the high purity level metal 14 is selected from the group consisting of copper, tungsten, nickel, titanium, aluminum, lead, tantalum and molybdenum. For instance, a copper powder having a hardness of about 77-99 Vickers (HV) (or 2.5 to 3.0 Mohs) and a tensile strength of 350 MPa may be utilized, with or without another high purity level metal 14. Without being bound by theory, it is believed that the hardness of the selected high purity level metal 14 will be reduced when the shaped charge liner 10 is heated. According to an aspect, the hardness of the high purity level metal may be reduced by an amount up to about 20%.
The melting temperatures of the high purity level metal 14 included in the shaped charge liner 10 helps the shaped charge liner 10 (when heated) maintain its mechanical integrity. According to an aspect, the high purity level metal 14 has a melting temperature greater than about 320° C. Alternatively, the high purity level metal 14 has a melting temperature greater than about 600° C., alternatively greater than about 1,050° C., alternatively greater than about 1,600° C., alternatively greater than about 3,000° C. According to an aspect, the heated shaped charge liner 10 maintains its mechanical integrity (i.e., its original shape) even when subjected to a temperature of at least about 250° C.
The plurality of metal powders 12 may include a first high purity level metal and a second high purity level metal. While the first and second high purity level metals may have substantially similar melting temperatures, it is contemplated that the first high purity level metal may have a melting temperature that is greater or less than the melting temperature of the second high purity level metal. For instance, in some embodiments, the first high purity level metal may have a melting temperature between about 320° C. to about 1,200° C., and the second high purity level metal may have a melting temperature between about 1,400° C. to about 3,500° C. In this configuration, the first high purity level metal will begin to soften, and may in some circumstance melt and adhere to the other metals 12 or other high purity level metals 14 in the shaped charge liner 10 at a lower temperature than the second high purity level metal.
According to an aspect, the first high purity level metal may be present in an amount of about 5% w/w to about 40% w/w of a total weight of the plurality of metal powders 12, while the second high purity level metal may be present in an amount of about 60% w/w to about 95% w/w of the total weight of the plurality of metal powders 12. The quantities of the first and second high purity level metals in the total weigh to the composition of metal powders 12 may be selected at least in part based on the ability of each high purity level metal's 14 ability to interact with each other and/or other constituents of the shaped charge liner 10.
The shaped charge liner 10 may include a binder 16. The binder 16 helps to maintain the shape and stability of the liner 10. According to an aspect, the binder 16 includes a high melting point polymer resin having a melting temperature greater than about 250° C. The resin may include a fluoropolymer and/or a rubber. In an embodiment, the high melting point polymer resin is Viton™ fluoroelastomer. The binder 16 may include a powdered soft metal, such as graphite, that is mixed in with the plurality of metal powders 12. In an embodiment, the powdered soft metal is heated (and may be melted) prior to being combined/mixed with the plurality of metal powders 12. This helps to provide for adequate dispersion and coating of the metal powders 12 within the shaped charge liner 10 and reduces or substantially eliminates the amount of dust that may form in the environment, thereby reducing the likelihood of creating a health hazard and reducing potential toxicity levels of the liner 10.
Embodiments of the liners of the present disclosure may be used in a variety of shaped charges 20, 30, which incorporate the above-described shaped charge liners 10. The shaped charges 20, 30 include a case 32 that has a closed end, an open end 33 opposite the closed end 31, and a plurality of walls (or wall) 35 extending between the closed and open ends 31, 33. As noted hereinabove, the shaped charge of
A shaped charge liner 10 may be disposed adjacent the explosive load 40 (or secondary explosive load 44), thus retaining the explosive load 40, 44 within the hollow interior 34 of the case 40. The liner 10, while shown in a conical configuration 10′ in the shaped charges of
For purposes of convenience, and not limitation, the general characteristics of the shaped charge liner 10 are described above with respect to
The process of allowing heat to be applied to the liners 10 and/or the shaped charges 20, 30 incorporating the liners 10 according to the present disclosure is contrary to the conventional wisdom that shaped charges must be initiated at ambient temperature immediately or soon after or deployment in the wellbore. It has surprisingly been found that the shaped charge liners 10 described herein do not have to be isolated or protected from the increased temperature of the wellbore, because the increase in temperature of the metal powders and high purity metal powders actually enhances the performance of the shaped charge liner 10. By virtue of the conveyance method for the perforating systems and the downhole temperature, the liners 10 are pre-conditioned by the exposure to the wellbore's temperature before the shaped charges are detonated in the wellbore. The liners 10 (within their respective casing and/or positioned in a perforating gun and/or a shaped charge carrier) are pre-conditioned by virtue of the wellbore having a temperature that is greater than an initial temperature of the shaped charge at the ground surface. The preheating treatment of the liner 10 changes the morphology of the liner 10 itself so that an enhanced collapse process of the shaped charge liner and an improved perforating jet performance will occur. When the liners 10 are heated in the wellbore, the metals 12, 14 soften, which helps to further bind the metals together. The temperature at which the liner is heated, and the length of the heat treatment, may be customized according to the types of powdered metals in the liners 10.
Embodiments further relate to a method of perforating a wellbore using a shaped charge having a shaped charge liner disposed therein, substantially as described hereinabove. As illustrated in the flow charts of
The initial ambient temperature of the shaped charge and the shaped charge liner, which is typically the initial ambient temperature at a surface (above ground) of the wellbore, is less than the temperature of the wellbore. Thus, when positioned in the wellbore, the shaped charge and shaped charge liner are both heated from their respective initial ambient temperatures to the wellbore temperature. As illustrated in the flow chart of
When heated in the wellbore, the shaped charge liner is thermally softened so that it has a porosity of less than about 20 volume % and maintains its mechanical integrity at a temperature of at least about 250° C. The step of heating 160 the shaped charge and the shaped charge liner modifies the shaped charge liner so its mechanical properties, including ductility, malleability and yield point are improved from the point of high velocity perforation jet formation. For instance, at least one of plurality of metals or the high purity level metal will have a yield point that is 30%, alternatively 15% to 20%, less than that of the equivalent metal at an ambient temperature of about 21° C. In addition, the plurality of metals and/or the high purity level metal has a reduction in hardness of at least about 20%.
Once the shaped charge and shaped charge liner are heated to the desired temperature, the heated shaped charge is detonated 180 into the wellbore, and the liner produces a perforating jet having a detonation velocity of up to about 8,500 meters/second. The liner forms a coherent and rapidly elongating perforating jet, which reduces particulation or separation of the perforation jet upon the detonating 180 of the heated shaped charge into the wellbore.
The present invention may be understood further in view of the following examples, which are not intended to be limiting in any manner. All of the information provided represents approximate values, unless specified otherwise.
Various shaped charge liners may be made according to the embodiments of the disclosure. The data presented in the Example shown in Table 1 are based on the theoretical properties of the high purity level metals 14 in the metal powders 12. Such high purity level metals 14 have purity levels of at least about 99.5%. The shaped charge liner may include about 5% of a total weight of its composition, other constituents that may aid in the mixing or combinability of the metal powders and high purity level metal powders.
The high purity level metals 14 presented in Table 1 may include tungsten, molybdenum and/or copper. Table 1 presents the hardness, tensile strength, and modulus of elasticity for tungsten, molybdenum and copper at an ambient temperature of about 21° C./69.8° F. and after each metal is subjected to a temperature of about 250° C./482° F. According to an aspect, the hardness and tensile strength of the tungsten, molybdenum and copper metals decrease when exposed to temperatures up to about 250° C. At 250° C., the elasticity of the tungsten, molybdenum and copper metals also slightly decrease. Without being bound by theory, it is believed that the heating of the high purity level metals of the shaped charge liner 10 reduces of the metals' hardness, tensile strength and modulus of elasticity in a manner that allows the shaped charge liner 10 to maintain its mechanical integrity and enhances the performance of the shaped charge liner 10 when used to perforate steel and rock formations. While several combinations of high purity level metals are contemplated, it has been found that including tungsten and copper, each having a purity level of about 99.5%.
The present disclosure, in various embodiments, configurations and aspects, includes components, methods, processes, systems and/or apparatus substantially developed as depicted and described herein, including various embodiments, sub-combinations, and subsets thereof. Those of skill in the art will understand how to make and use the present disclosure after understanding the present disclosure. The present disclosure, in various embodiments, configurations and aspects, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments, configurations, or aspects hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and/or reducing cost of implementation.
The phrases “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
In this specification and the claims that follow, reference will be made to a number of terms that have the following meanings. The terms “a” (or “an”) and “the” refer to one or more of that entity, thereby including plural referents unless the context clearly dictates otherwise. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. Furthermore, references to “one embodiment”, “some embodiments”, “an embodiment” and the like are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term such as “about” is not to be limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Terms such as “first,” “second,” “upper,” “lower” etc. are used to identify one element from another, and unless otherwise specified are not meant to refer to a particular order or number of elements.
As used herein, the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of “may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances the modified term may sometimes not be appropriate, capable, or suitable. For example, in some circumstances an event or capacity can be expected, while in other circumstances the event or capacity cannot occur—this distinction is captured by the terms “may” and “may be.”
As used in the claims, the word “comprises” and its grammatical variants logically also subtend and include phrases of varying and differing extent such as for example, but not limited thereto, “consisting essentially of” and “consisting of.” Where necessary, ranges have been supplied, and those ranges are inclusive of all sub-ranges therebetween. It is to be expected that variations in these ranges will suggest themselves to a practitioner having ordinary skill in the art and, where not already dedicated to the public, the appended claims should cover those variations.
The foregoing discussion of the present disclosure has been presented for purposes of illustration and description. The foregoing is not intended to limit the present disclosure to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the present disclosure are grouped together in one or more embodiments, configurations, or aspects for the purpose of streamlining the disclosure. The features of the embodiments, configurations, or aspects of the present disclosure may be combined in alternate embodiments, configurations, or aspects other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the present disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, the claimed features lie in less than all features of a single foregoing disclosed embodiment, configuration, or aspect. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of the present disclosure.
Advances in science and technology may make equivalents and substitutions possible that are not now contemplated by reason of the imprecision of language; these variations should be covered by the appended claims. This written description uses examples to disclose the method, machine and computer-readable medium, including the best mode, and also to enable any person of ordinary skill in the art to practice these, including making and using any devices or systems and performing any incorporated methods. The patentable scope thereof is defined by the claims, and may include other examples that occur to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
This application claims the benefit of U.S. Provisional Application No. 62/558,552 filed Sep. 14, 2017, and U.S. Provisional Application No. 62/594,709 filed Dec. 5, 2017, each of which is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2018/074219 | 9/7/2018 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62558552 | Sep 2017 | US | |
| 62594709 | Dec 2017 | US |
