Described generally herein is an initiator head assembly having an embedded electric feed-through for use with a perforating gun assembly, in particular for oil well drilling applications.
In exploration and extraction of hydrocarbons, such as fossil fuels (e.g. oil) and natural gas, from underground wellbores extending deeply below the surface, various downhole tools are inserted below the ground surface and include sometimes complex machinery and explosive devices. Examples of the types of equipment useful in exploration and extraction, in particular for oil well drilling applications, include logging tools and perforation gun systems and assemblies. It is often useful to be able to maintain a pressure across one or more components as necessary to ensure that fluid does not leak into the gun assembly, for instance. It is not uncommon that components such as an initiator are components in such perforating gun assemblies that succumb to pressure leakage. It is particularly useful that one or more of the components is able to maintain a pressure differential even after, for instance, detonation of one or more downstream components.
The initiator is one of many components of the perforating gun system for which continual improvement is sought. There are at least 2 known types of initiators—a detonator and an igniter.
Upon placement into the perforating gun assembly, one or more initiators have traditionally required physical connection of electrical wires. The electrical wires typically travel from the surface down to the perforating gun assembly, and are responsible for passing along the surface signal required to initiate ignition. The surface signal typically travels from the surface along the electrical wires that run from the surface to one or more detonators positioned within the perforating gun assembly. Such initiators typically require electronic componentry and/or wiring to pass through a body thereof, (e.g. electric feed-through), and a need exists to provide such componentry having electric feed-through while maintaining a differential pressure across the component. Passage of such wires through the initiator, while maintaining a pressure differential across the component, has proved challenging.
Assembly of a perforating gun requires assembly of multiple parts, which typically include at least the following components: a housing or outer gun barrel within which is positioned an electrical wire for communicating from the surface to initiate ignition, an initiator, a detonating cord, one or more charges which are held in an inner tube, strip or carrying device and, where necessary, one or more boosters. Assembly typically includes threaded insertion of one component into another by screwing or twisting the components into place, optionally by use of a tandem adapter. Since the electrical wire must extend through much of the perforating gun assembly, it is easily twisted and crimped during assembly. In addition, when a wired detonator is used it must be manually connected to the electrical wire, which has lead to multiple problems. Due to the rotating assembly of parts, the wires can become torn, twisted and/or crimped/nicked, the wires may be inadvertently disconnected, or even mis-connected in error during assembly, not to mention the safety issues associated with physically and manually wiring live explosives.
According to the prior art and as shown in
Improvements to the way these electrical connections are accomplished include connections and arrangements as found in commonly assigned patent applications PCT/EP2012/056609 (in which an initiator head is adapted to easily introduce external wires into the plug without having to strip the wires of insulation beforehand) and DE 10 2013 109 227.6 (in which a wireless initiator is provided), which are incorporated herein by reference in their entirety.
The assembly described herein further solves the problems associated with prior known assemblies in that it provides, in an embodiment, an assembly to improve manufacturing costs and assembly in the field, as described in greater detail hereinbelow.
In an embodiment, an initiator head assembly includes a body and an electrical contact component extending through the body and embedded in the body, such that the body seals around the electrical contact component against pressure leakage across the body to maintain a higher pressure at a first end of the body as compared to a second end of the body, when the body is positioned within the downhole tool.
In an embodiment, at least the body has been formed as a unitary component.
In an aspect, a method of forming the initiator head assembly is provided.
A more particular description briefly described above will be rendered by reference to specific embodiments thereof that 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 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 embodiments.
Reference will now be made in detail to various embodiments. Each example is provided by way of explanation, and is not meant as a limitation and does not constitute a definition of all possible embodiments.
In an embodiment, the assembly provides an improved apparatus for use with a wireless connection—that is, without the need to attach, crimp, cut or otherwise physically and manually connect external wires to the component. Rather, the connections are made wirelessly, by simply abutting, for instance, electrically contactable components, of which at least a portion thereof is positioned proximal to an external surface of the pressure barrier. As used herein, the term “proximal” means on or near or next to or nearest or even embedded within. For the sake of clarity, the term “wireless” does not refer to a WiFi connection, but rather to this notion of being able to transmit electrical signals through the electrical componentry without connecting external wires to the component. The apparatus described herein solves the problems associated with the prior known assemblies in that it provides an assembly including the wireless connection integrated therein, to improve manufacturing costs and assembly in the field.
In an embodiment, an assembly is provided that is capable of being placed into a perforating gun assembly or other downhole tool such as a setting tool with minimal effort. Specifically, an initiator head assembly 10, as found in
Turning specifically to
With reference again to
The base 30 of the body 20 includes a first end 32 and a second end 34. In an embodiment, the first end 32 of the base 30 is formed integrally with the second surface 26 of the head 22. In an embodiment, an opening 36 extends along at least a portion of a side or outer surface of the base 30, and the opening 36 extends at least partially along a length of the base 30 between the first end 32 and the second end 34. In an alternative embodiment, it is possible to form the head 22 separately from the base 30, and to join the components together after formation through the use of adhesives, fasteners and the like.
The initiator head assembly 10 further includes an electrical contact component 40 that may be formed from an electrically conductive material, as would be understood by those of ordinary skill in the art. The electrical contact component 40 includes individual elements as discussed in greater detail below. In an embodiment, the electrical contact component 40 is also formed as a unitary member with electrical insulators positioned between the elements, while in another embodiment, the individual elements of the component 40 can be made separately and soldered or otherwise connected to form the elements of the component 40. The individual elements of the electrical contact component 40 can be formed of any electrically conductive material and using known methods such as wire forming, stamping, bending and the like.
With reference to
In an embodiment, the electrical contact component 40 is integrally formed with the body 20 such that the line-in portion 42 of the electrical contact component 40 is positioned proximal to the first surface 24 of the head 22 of the body 20 and the line-out portion 44 of the electrical contact component 40 is positioned proximal to the second surface 26, and the ground portion 46 of the electrical contact component 40 is positioned proximal to the opening 36 of the base 30 of the body 20. In an embodiment, the opening 36 is configured to allow at least a portion of the ground portion 46 to extend at least partially beyond an outer surface of the base 30. With reference to
In an embodiment, the ground portion 46 in combination with the line-in portion 42 and the line-out portion 44 are configured to complete a wireless electrical connection by the electrical contact component 40 merely by contact, without using a wired electrical connection, when configured as depicted herein and positioned within the perforating gun assembly (not shown).
As depicted in
In yet a further embodiment and as seen in
In an embodiment the ground portion 46 is flexible and extends through the opening 36 slightly beyond an external surface of the base 30. In this way, once the base 30 is seated or otherwise positioned within the shell 50, the ground portion 46 is placed in electrically contacting position with the ground portion 52 of the shell 50. That is, the electrical contact is made without using a wired electrical connection.
With reference to
In this embodiment, the body 120 includes the head 122 that extends from the base 130, and the entire body 120 is formed as a unitary member or component. Methods of forming the body 120 as a unitary member are as set forth above.
With reference particularly to
The base 130 of the body 120 includes a first end 132 and a second end 134. In an embodiment, the first end 132 of the base 130 is formed integrally with the second surface 126 of the head 122. In an alternative embodiment, it is possible to form the head 122 separately from the base 30, and to join the components together after formation through the use of adhesives, fasteners and the like. As depicted herein, the base 130 includes one or more (two shown) indentations or notched or recessed areas 131, which are configured for sealing the initiator head assembly 110 when positioned with an end of the shell 150 (see, for instance,
With particular reference to
Another way to describe the differential pressure experienced by the initiatory head assembly 110 found in
In an embodiment, the body 120 is injection molded and configured as a sealed unit to maintain the differential pressure between the outer surface 154 and the inner surface 155. Turning again to
In an embodiment, a method of making an initiator head assembly 10,110 includes the steps of forming the electrical contact component 40, 140 and the body 20, 120. As contemplated and as discussed above, it is possible to form the body 20, 120 as a unitary component around the electrical contact component 40, 140. In an embodiment, the method of making the initiator head assembly 10, 110, includes embedding the electrical contact component 40, 140 within the body 20, 120, and in particular embedding the electrical contact component 40, 140 within the body 20 during formation of the body 20.
In an embodiment, the initiator 100, 200 including the initiator head assembly 10, 110 described in detail herein is configured for being electrically contactably received within a perforating gun assembly without using a wired electrical connection.
In an embodiment, the line-in portion 42, 142, and the line-out portion 44, with or without the ground portion 46, 144 are configured to replace the wired connection of the prior art wired detonator 60 and to complete the electrical connection merely by contact with other electrical contacting components. In this way, the line-in portion 42, 142 of the assembly 10, 110 replaces the signal-in wire 61 of the wired detonator 60, and the line-out portion 44, replaces the signal-out wire 62 and the ground portion 46, 144 replaces the ground wire 63. Thus, when placed within the perforating gun assembly, the line-in portion 42, 142, and the line-out portion 44, with or without the ground portion 46, 144 make an electrical connection by merely making contact with corresponding electrical contacting components provided within the gun assembly. That is, the initiator head assembly 10, 110 is wirelessly connectable only by making and maintaining electrical contact of the electrical contacting components to replace the wired electrical connection and without using a wired electrical connection.
In an embodiment, the initiator 100, 200 is configured to wirelessly and selectively receive an ignition signal, (typically a digital code uniquely configured for a specific detonator), to fire the perforating gun assembly. By “selective” what is meant is that the initiator is configured to receive one or more specific digital sequence(s), which differs from a digital sequence that might be used to arm and/or detonate another initiator in a different, adjacent perforating gun assembly, for instance, a train of perforating gun assemblies. So, detonation of the various assemblies does not necessarily have to occur in a specified sequence. Any specific assembly can be selectively detonated. In an embodiment, the detonation occurs in a top-down or bottom-up sequence.
In an embodiment, the initiator 100, 200 may be fluid disabled. “Fluid disabled” means that if the perforating gun has a leak and fluid enters the gun system then the detonator is disabled by the presence of the fluid and hence the explosive train is interrupted. This prevents a perforating gun from splitting open inside a well if it has a leak and plugging the wellbore, as the hardware would burst open. In an embodiment, the initiator 100, 200 is a selective fluid disabled electronic (SFDE) assembly.
The initiator 100, 200 according to an aspect can be either an electric or an electronic detonator. In an electric detonator, a direct wire from the surface is electrically contactingly connected to a detonator assembly and power is increased to directly initiate a fuse head. In an electronic detonator assembly, circuitry of an electronic circuit board within the detonator assembly is used to initiate the fuse head.
In an embodiment, the initiator 100, 200 may be immune to stray current or voltage and/or radiofrequency (RF) signals or induced currents to avoid inadvertent firing of the perforating gun or setting tool or any other downhole tool. Thus, in this embodiment, the initiator 100, 200 is provided with means for ensuring immunity to stray current or voltage and/or RF signals, such that the initiator 100, 200 is not initiated through random radio frequency signals, stray voltage or stray current. In other words, the initiator 100, 200 is configured to avoid unintended initiation.
The components and methods illustrated are not limited to the specific embodiments described herein, but rather, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. Such modifications and variations are intended to be included. Further, steps described in the method may be utilized independently and separately from other steps described herein.
While the apparatus and method have been described with reference to various embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope. In addition, many modifications may be made to adapt a particular situation or material to the teachings without departing from the essential scope thereof. In the interest of brevity and clarity, and without the need to repeat all such features, it will be understood that any feature relating to one embodiment described herein in detail, may also be present in an alternative embodiment. As an example, it would be understood by one of ordinary skill in the art that if the electrical contact component 40 of one embodiment is described as being formed of an electrically conductive material, that the electrical contact component 140 described in the alternative embodiment is also formed of an electrically conductive material, without the need to repeat all such features.
In this specification and the claims that follow, reference will be made to a number of terms that have the following meanings. The singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Furthermore, references to “one embodiment” are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Terms such as “first,” “second,” 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.”
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, including the best mode, and also to enable any person of ordinary skill in the art to practice, including making and using any devices or systems and performing any incorporated methods. The patentable scope 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 languages of the claims.
This application is a continuation of U.S. application Ser. No. 15/331,954 filed Oct. 24, 2016, which claims priority to PCT Application No. PCT/EP2015/0059381 filed Apr. 29, 2015, which claims the benefit of U.S. Provisional Application No. 61/988,722, filed May 5, 2014, and U.S. Provisional Application No. 62/050,678, filed Sep. 15, 2014, all of which are incorporated herein by reference in their entireties.
Number | Date | Country | |
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62050678 | Sep 2014 | US | |
61988722 | May 2014 | US |
Number | Date | Country | |
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Parent | 15331954 | Oct 2016 | US |
Child | 15788367 | US |