Patent Description:
<CIT>, in accordance with its abstract, relates to a plug for ports having a flexible handle to facilitate the removal of the plug from a port. A flange is integrally attached to an end of the plug body and extends radially outwardly from the body. One or more openings are formed in the flange which form handles concentric to the body. The openings have ends spaced from each other providing lands that attach the handles to the flange. The openings are spaced inward from the outer edges of the flange and the handles provided can be swung toward each other and grasped by a hand to pull the plug out of a port.

<CIT>, in accordance with its abstract, relates to a closing method involving placing a bore in a workpiece, where the bore in an area of the workpiece near to a surface has a bigger diameter than in the area of the workpiece away from the surface. A step is formed between the two areas. A cover plate is inserted into the bore, where the diameter of the cover plate corresponds to the inner diameter of the bore in the area of the workpiece that is near the surface. The cover plate is fixed in the bore by using an ultrasonic welding process or a rotary friction welding process.

<CIT>, in accordance with its abstract, relates to a rotary tool for use with a rotary driving unit for inserting a component through a surface of a workpiece made of a material showing friction-induced plasticity such as aluminum, including a tool body having a working end defining a shoulder portion and a securing device for selectively engaging the component to impart rotation thereof in a first direction while applying an axial force of a sufficient magnitude onto the component to produce insertion thereof by plasticizing the material through friction. The shoulder portion is provided with a deburring device capable of being displaced from an inoperative position upon rotation of the tool body in the first rotation direction, to an operative position whenever the tool body is caused to rotate in an opposite direction, to provide deburring of the workpiece surface.

<CIT>, in accordance with its abstract, relates to a closure element which is a tensioning pin which can be tensioned and the head part of which forms a closure disc that can be spread apart by the tensioning pin. The closure disc is pressed, in the installed state, against the inner wall of the bore to be closed. When a specific tensile stress is reached, the tensioning pin is separated from the closure disc at a predetermined breaking point of the tensioning pin. The easy-to-handle tensioning pin facilitates the installation of the closure in the bore in the component. Since the closure disc is pressed against an outer counterholder during the installation process, it can be inserted into a continuously smooth bore. The limitation of the tensile stress effected by way of the predetermined breaking point also ensures that the bore is closed with a defined closing force.

<CIT> (describing the preamble of claim <NUM>), in accordance with its abstract, states that a problem to be solved (by <CIT>) is to enable rotary friction welding equipment to be miniaturized by reducing friction torque in rotary friction welding. A proposed solution (in <CIT>) is a tapered plug formed in a truncated cone shape, with the conical angle set smaller than the angle formed by a tapered hole; the tapered plug, when inserted into the tapered hole, is made to come into contact with the tapered hole only at the tip end of the plug; and welding is performed successively from the tip end part.

Accordingly, articles for and methods of filling openings in objects, intended to address the above-identified concerns, would find utility.

A method of installing a plug into an opening in an object according to the present invention is defined in claim <NUM>, with the following features: the plug including a body, a first flange, and a second flange, wherein the first flange is in contact with the body and extends away from the body and wherein the second flange is in contact with the first flange and extends away from the first flange and the body, wherein the second flange is made of a different material than the first flange, and the different material that the second flange is made of is softer than the material of the first flange, thereby allowing the second flange to deform during installation of the plug into the opening, while maintaining the first flange substantially intact, the method including: installing the plug into the opening to consolidate the plug in the opening and to rotationally and translationally secure the plug in the opening, including urging the plug into the opening, thereby deforming the second flange toward the body.

Having thus described examples, disclosed herein, in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein like reference characters designate the same or similar parts throughout the several views, and wherein:.

In the block diagram(s) referred to above, solid lines connecting various elements and/or components may represent mechanical, electrical, fluid, optical, electromagnetic and other couplings and/or combinations thereof. As used herein, "coupled" means associated directly as well as indirectly. For example, a member A may be directly associated with a member B, or may be indirectly associated therewith, e.g., via another member C. Couplings other than those depicted in the block diagram(s) may also exist. Dashed lines, if any, connecting the various elements and/or components represent couplings similar in function and purpose to those represented by solid lines; however, couplings represented by the dashed lines are either selectively provided or relate to alternative or optional aspects of the disclosure. Likewise, any elements and/or components, represented with dashed lines, indicate alternative or optional aspects of the disclosure. Environmental elements, if any, are represented with dotted lines.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented concepts. The presented concepts may be practiced without some or all of these specific details. In other instances, well known process operations have not been described in detail so as to not unnecessarily obscure the described concepts. While some concepts will be described in conjunction with the specific examples, it will be understood that these examples are not intended to be limiting.

Referring, e.g., to <FIG>, <FIG>, <FIG>, and <FIG>, one example of the present disclosure relates to an article <NUM> for filling an opening <NUM> (<FIG>) in an object <NUM>. The article <NUM> includes a plug <NUM> having a body <NUM>, a first flange <NUM>, and a second flange <NUM>. As shown, e.g., in <FIG>, the first flange <NUM> is in contact with the body <NUM> and extends away from the body <NUM>. The second flange <NUM> is in contact with the first flange <NUM> and extends away from the first flange <NUM> and the body <NUM>. The second flange <NUM> is configured to deform toward the body <NUM> upon installation of the plug <NUM> into the opening <NUM>. This deformation of the second flange <NUM> rotationally and translationally secures the plug <NUM> in the opening <NUM> and consolidates the plug <NUM> in the opening <NUM>. The deformation of the second flange <NUM> is discussed below, e.g., with reference to <FIG>. In some examples, the first flange <NUM> may remain generally intact during deformation of the second flange <NUM>. The first flange <NUM> and the body <NUM> may delimit at least a portion of a gap <NUM> for receiving the second flange <NUM> during the deformation thereof.

Referring, e.g., to <FIG>, in one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the article <NUM> also includes a shaft <NUM> frangibly coupled to the plug <NUM>. The shaft <NUM> is decoupled from the plug <NUM> during installation of the plug <NUM> into the opening <NUM>, as further described below with reference to <FIG> and <FIG>. For example, the shaft <NUM> may include a narrow neck <NUM> connecting the shaft <NUM> to the plug <NUM>.

Referring to <FIG>, in one aspect of the present disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the plug <NUM> includes a trailing end <NUM>. A portion of the trailing end <NUM> is configured to protrude above a surface <NUM> (<FIG>) of the object <NUM> when the plug <NUM> is installed into the opening <NUM> (<FIG>). Specifically, <FIG> illustrates the plug <NUM> installed in the opening <NUM> with a portion of the trailing end <NUM> or, more specifically, a portion of the trailing surface <NUM> extending above the surface <NUM> of the object <NUM>.

Referring once again to <FIG>, in one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the article <NUM> may also include a third flange124 and a fourth flange <NUM>. The third flange <NUM> is in contact with the body <NUM> and extends away from the body <NUM>. The fourth flange <NUM> is in contact with the third flange <NUM> and extends away from the third flange <NUM> and the body <NUM>. The fourth flange <NUM> is configured to deform toward the body <NUM> and toward the first flange <NUM> upon installation of the plug <NUM> into the opening <NUM> as, for example, shown in <FIG>. Similar to the deformation of the second flange <NUM>, the deformation of the fourth flange <NUM> rotationally and translationally secures the plug <NUM> in the opening <NUM> and consolidates the plug <NUM> in the opening <NUM>. The gap <NUM> between the first flange <NUM> and the third flange <NUM> may have the same size (e.g., volume) as the size (e.g., volume) of the fourth flange <NUM> to accommodate the deformation of the fourth flange <NUM> into the gap during the installation of the plug <NUM> into the opening <NUM>. After the installation, the third flange <NUM> may remain generally intact, similar to the first flange <NUM>.

The first flange <NUM> and the second flange <NUM> of the plug <NUM> form an arrangement of flanges. When additional arrangements of flanges are present, such as the third flange <NUM> and the fourth flange <NUM>, described above, one flange in each of the arrangements may be received into the corresponding gap <NUM> in a manner similar to the second flange <NUM> and the fourth flange <NUM>. The plug <NUM> may include, e.g., one, two, three, four, five arrangements of flanges, and so on. For example, <FIG> illustrates the plug <NUM> having three such arrangements disposed along the body <NUM>. The first arrangement is formed by the first flange <NUM> and the second flange <NUM>, the second arrangement is formed by the third flange <NUM> and the fourth flange <NUM>, and the third arrangement is formed by the fifth flange <NUM> and the sixth flange <NUM>. Adjacent flanges in contact with the body <NUM>, e.g., the first flange <NUM> and the third flange <NUM>, may delimit at least a portion of the gap <NUM> for receiving, e.g., the fourth flange <NUM> during the deformation thereof resulting from the installation of the plug <NUM> into the opening <NUM>. Each additional arrangement of flanges further rotationally and translationally secures the plug <NUM> into the opening <NUM>. Multiple arrangements of flanges may be distributed along the length of the plug <NUM>, providing frictional interference with the object <NUM> at different locations. Furthermore, for a given length of the plug <NUM> (generally corresponding to the depth of the opening <NUM>), increasing the number of arrangements of flanges allows using smaller flanges that may be easier to deform.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the body <NUM> may have a frusto-conical shape. Furthermore, the collective taper of the inner flanges, e.g., the first flange <NUM>, the third flange <NUM>, and any other flange in contact with the body <NUM>, may be substantially the same as the taper of the opening. In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the fourth flange <NUM> has a smaller diameter than the second flange <NUM>. It should be noted that the second flange <NUM> is disposed closer to the trailing end <NUM> of the plug <NUM> than the fourth flange <NUM>. This type of the plug <NUM> may be used for tapered holes. Generally, a volume of each outer flange, e.g., the second flange <NUM>, the fourth flange <NUM>, and any other flange not directly in contact with the body <NUM>, may correspond or, more specifically, may be substantially equal to the volume of a corresponding gap <NUM> configured to receive such flange. This volume correspondence allows achieve full consolidation of the plug <NUM> in the opening <NUM> once the plug is inserted into the opening. Furthermore, the difference between the outer and inner radii of each outer flange, which may be referred to as a length of the flange, may not exceed the height of the corresponding gap configured to receive such flange to ensure that the flange fits into the gap during consolidation of the plug <NUM> into the opening <NUM>. For example, if the length of the outer flange is greater than the height of the gap, the outer flange may bridge the gap rather than fit inside the gap.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the body <NUM>, the first flange <NUM>, and the second flange <NUM> form a monolithic structure. For example, the body <NUM>, the first flange <NUM>, and the second flange <NUM> may be machined from a single piece of parent material.

In another aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the body <NUM>, the first flange <NUM>, and the second flange <NUM> may be fabricated as separate components and then assembled together. For example, the first flange <NUM> may be removably attached to the body <NUM>, e.g., with a locational interference fit. The second flange <NUM> may be removably attached to the first flange <NUM> in a similar manner. In some aspects, the assembly of the plug <NUM> is performed to accommodate the installation of the plug <NUM> into the opening <NUM> of a given size, and the flanges are selected based on the size of the opening <NUM>. In other words, the article <NUM> may be provided as a reconfigurable kit of multiple components. In one aspect, the article <NUM> may be supplied with multiple first flanges having different sizes and/or multiple second flanges having different sizes to accommodate openings of different size.

According to the present invention, second flange <NUM> is made of a different material than the first flange <NUM>. Further according to the present invention, the second flange <NUM> is made from a material that is softer than the material of the first flange <NUM>, thereby allowing the second flange <NUM> to deform while maintaining the structure of the first flange <NUM> substantially intact. The body <NUM> may be made of a different material than the first flange <NUM> and/or the second flange <NUM>.

Referring once again to <FIG>, in one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange <NUM> includes a slip feature <NUM> formed on a trailing outer corner <NUM> of the second flange <NUM>. The slip feature promotes consolidation of the second flange <NUM> into the gap <NUM> during installation of the plug <NUM> into the opening <NUM> by reducing friction between the trailing outer corner <NUM> of second flange <NUM> and other surfaces, such as those of the plug <NUM>. For example, during installation of the plug <NUM> into the opening <NUM>, as illustrated in <FIG>, the trailing outer corner <NUM> may come in contact with a leading surface <NUM> of the trailing end <NUM> of the plug. In one aspect, the slip feature <NUM> may be implemented as a radius of the corner <NUM> and a chamfer on the corner <NUM>.

In one aspect of the present disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange <NUM> includes an anchor feature <NUM> formed on a leading outer corner <NUM> of the second flange <NUM>. The anchor feature <NUM> is configured to engage the surface of the inside wall of the opening <NUM> (<FIG>) during insertion of the plug <NUM> therein. Once engaged with the surface of the opening <NUM>, the anchor feature <NUM> promotes deformation of the second flange <NUM> away from the direction of insertion of the plug <NUM> into the opening <NUM> and toward the body <NUM> of the plug into the gap <NUM>. In one aspect, the anchor feature may be an apical edge formed by two intersecting surfaces of the second flange <NUM>.

As shown, e.g., in <FIG> and <FIG>, the fourth flange <NUM> may include a slip feature 125d formed on a trailing outer corner 125c of the fourth flange <NUM>. The fourth flange <NUM> may also include an anchor feature 125b formed on a leading outer corner 125a of the fourth flange <NUM>. Similarly, the sixth flange <NUM> may include a slip feature 127d formed on a trailing outer corner 127c of the sixth flange <NUM>. The sixth flange <NUM> may also include an anchor feature 127b formed on a leading outer corner 127a of the sixth flange <NUM>. Likewise, any other outer flange, such as the second flange <NUM>, may include a slip feature formed on its trailing outer corner and/or an anchor feature formed on its leading outer corner.

In one aspect of the present disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects flanges, such as the first flange <NUM> and the second flange <NUM>, have an annular shape or a spiral shape. <FIG> illustrates the first flange <NUM> and the second flange <NUM> having annular shapes. Specifically, the first flange <NUM> and the second flange <NUM> are symmetric about a longitudinal axis of the opening <NUM> (<FIG>). The plug <NUM> having annular flanges may be installed into the opening <NUM> by urging (linearly advancing and/or rotating) the plug <NUM> into the opening <NUM> (<FIG>). The plug <NUM> having spiral flanges may be installed into the opening <NUM> by linearly advancing the plug <NUM> into the opening <NUM> and/or by rotating the plug <NUM> around the longitudinal axis of the opening <NUM>. For example, the plug <NUM> may have spiral flanges that correspond to a helical thread in the exit hole of the weld.

The disclosure and drawing figure(s) describing the operations of the method(s) set forth herein should not be interpreted as necessarily determining a sequence in which the operations are to be performed. Rather, although one illustrative order is indicated, it is to be understood that the sequence of the operations may be modified when appropriate. Additionally, in some aspects of the disclosure, not all operations described herein need be performed.

As shown in <FIG>, one example of the present disclosure relates to a method of installing the plug <NUM> into the opening <NUM> in the object <NUM> (<FIG>). The method of installing the plug <NUM> is, according to the present invention, a standalone method that does not include one or both friction stir welding operations described below. The method of installing the plug <NUM> may include providing the plug <NUM> having the body <NUM>, the first flange <NUM>, and the second flange <NUM> (operation <NUM>). As described above, the first flange <NUM> is in contact with the body <NUM> and extends away from the body <NUM>. The second flange <NUM> is in contact with the first flange <NUM> and extends away from the first flange <NUM> and the body <NUM>. The method includes installing the plug <NUM> into the opening <NUM> (operation <NUM>) to consolidate the plug <NUM> in the opening <NUM> and rotationally and translationally secure the plug <NUM> in the opening <NUM>. Installing the plug <NUM> into the opening <NUM> includes, according to the present invention, urging the plug <NUM> into the opening <NUM> thereby deforming the second flange <NUM> toward the body112 (operation <NUM>).

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange <NUM> includes the anchor feature <NUM> on the leading outer corner <NUM> of the second flange <NUM>. As the plug <NUM> is urged into the opening <NUM>, the anchor feature <NUM> grips a wall <NUM> of the opening <NUM>, causing the second flange <NUM> to deform toward the body <NUM>. Various aspects of the anchor feature <NUM> are described above.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange <NUM> includes a slip feature <NUM> on the trailing outer corner <NUM> of the second flange <NUM>. As the plug <NUM> is urged into the opening <NUM>, the slip feature <NUM> allows the second flange <NUM> to deform toward the body <NUM> by reducing friction between the second flange <NUM> and other elements of the plug <NUM>. Various aspects of the slip feature <NUM> are described above.

As discussed above, the consolidation of the plug <NUM> in the opening <NUM> may include deforming the second flange <NUM> toward the body <NUM>. In some aspects, one or more additional outer flanges may be deformed during the operation <NUM>. The plug <NUM> may substantially completely fill the opening <NUM> and, preferably, leaves substantially no voids in the opening <NUM> after installation of the plug <NUM> therein. A sectional view of the plug <NUM> installed into the opening <NUM> is shown in <FIG>. The opening <NUM> may be created, for example, during a friction stir welding operation, as is further described below with reference to <FIG>.

<FIG> illustrates the plug <NUM> and the object <NUM> prior to installing the plug <NUM> into the opening <NUM>. Referring to <FIG>, it is apparent that the radial dimensions of one or more outer flanges, such as the second flange <NUM>, exceed those of the corresponding portion(s) of the opening <NUM>. Those skilled in the art will appreciate that <FIG> is a hypothetical sectional view of an overlap between the outer flanges (e.g., the second flange <NUM>) of the plug <NUM> and an imaginary object profile <NUM>.

Accordingly, insertion of the plug <NUM> into the opening <NUM> during operation <NUM> causes one or more outer flanges, e.g., the second flange <NUM>, to deform, allowing the plug <NUM> to be fully inserted into the opening <NUM>. As illustrated in <FIG>, the outer flange(s) are deformed into the available gap(s). For example, the second flange <NUM> may be consolidated into the gap between the first flange <NUM> and the trailing end <NUM>. Similarly, the fourth flange <NUM> may be consolidated into the gap between the first flange <NUM> and the third flange <NUM>. Additional outer flanges may be deformed into gaps formed between corresponding adjacent inner flanges. Some deformation of the object <NUM>, the inner flanges (e.g., flanges <NUM>, <NUM>, and <NUM>) and the body112 may also occur during installation of the plug <NUM> into the opening <NUM>.

Referring generally to <FIG>, one example of the present disclosure relates to a method of friction stir welding the object <NUM> (<FIG>). The method includes performing a first friction stir weld <NUM> (<FIG>) along a first weld path having an exit <NUM>(operation <NUM>). The first friction stir <NUM> weld causes the opening <NUM> to form in the object <NUM> at the exit <NUM> of the weld path. The method also includes installing the plug <NUM> (<FIG>) into the opening <NUM> (operation <NUM>). The plug <NUM> is consolidated in the opening <NUM> and is rotationally and translationally secured in the opening <NUM> upon installation. The method also includes performing a second friction stir weld <NUM> (<FIG>) along a second weld path traversing the opening <NUM> that contains the plug <NUM> installed therein (operation <NUM>). The installed plug <NUM> is at least partially consumed in the second friction stir weld <NUM>.

Each of these operations will now be described in more detail. <FIG> is a top schematic view of the object <NUM> illustrating a first friction stir weld <NUM> and the opening <NUM>. The opening <NUM> is formed at the terminus of the first friction stir weld <NUM> as the welding tool exits the object <NUM>. A sectional view of the opening <NUM> is provided in <FIG>. In general, the opening <NUM> may vary in size and profile depending on the design of the weld tool and on the thickness and type of the weld. For example, the weld tool may have tapered threads causing roughness on the side walls of the opening <NUM>. However, not all weld tools have this feature.

<FIG> is a top schematic view of the object <NUM> illustrating the plug <NUM> installed in the opening <NUM>. A sectional view of the plug <NUM> installed into the opening <NUM> is depicted in <FIG>. Another view of the plug <NUM> installed into the opening <NUM> is shown in <FIG>. Specifically, <FIG> is a sectional perspective view of two objects <NUM> and <NUM>, friction stir welded together and joined by a weld <NUM>, with the plug <NUM> installed into the opening <NUM> created by the weld <NUM>. The objects <NUM> and <NUM> may be made from the same or different materials. The weld <NUM> is formed by combining (intermixing) plasticized material from both objects <NUM> and <NUM>.

<FIG> is a top schematic view of the object <NUM> showing an illustrative second friction stir weld <NUM>, with the plug <NUM>(represented as element <NUM>) at least partially consumed therein. <FIG> a sectional view of the friction stir weld <NUM> with the plug <NUM> (represented as element <NUM>) at least partially consumed therein. Preferably, the plug <NUM> is substantially completely integrated into the weld <NUM>.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, installing the plug <NUM> into the opening <NUM> includes urging the plug <NUM> into the opening <NUM> during operation <NUM>.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, urging the plug <NUM> into the opening <NUM> includes applying an impact to the plug <NUM> (block <NUM> in <FIG>) and/or applying a torque to the plug <NUM> (block <NUM> in <FIG>). The impact may be applied to the shaft <NUM> frangibly coupled to the plug <NUM>. This impact may decouple the shaft <NUM> from the plug <NUM>, as shown, e.g., in <FIG>. Likewise, the torque applied to the plug may decouple the shaft <NUM> from the plug <NUM>. <FIG> illustrates plug <NUM> without the shaft <NUM>.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the plug <NUM> may be consolidated in the opening <NUM> by deforming the flange 123of the plug <NUM> toward the body <NUM> of the plug <NUM>. For example, the flange <NUM> may be deformed by urging the plug <NUM> into the opening <NUM>(operation <NUM>). As discussed above, the plug <NUM> may include one or more outer flanges, such as the second flange <NUM>.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the plug <NUM> is consolidated in the opening <NUM> substantially without voids. Deformation of one or more outer flanges toward the body of the plug <NUM> fills the gaps <NUM> between the inner flanges (<FIG>). As such, once the plug <NUM> is installed into the opening <NUM> in the object <NUM>, there are substantially no voids between the plug <NUM> and the object <NUM>.

In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the plug <NUM> comprises the trailing end <NUM>. At least a portion of the trailing end <NUM> protrudes from the opening <NUM> above the surface <NUM> of the object <NUM> when the plug <NUM> is installed in the opening <NUM> as, shown, for example, in <FIG>. The trailing end <NUM> is urged into the opening <NUM> by a friction stir welding tool <NUM> during the second friction stir weld <NUM>, as shown, for example, in <FIG>, which is a sectional view of the installed plug <NUM> illustrating the trailing surface <NUM> of the trailing end <NUM> being engaged by the friction stir welding tool <NUM>. Through this engagement, the plug <NUM> is urged into the opening <NUM>, thereby promoting plasticizing of the plug and intermixing it with the parent material of the object <NUM>. The tapered shape of the trailing surface <NUM> facilitates initial engagement of the trailing end <NUM> of the plug <NUM> by the friction stir welding tool <NUM>. In some aspects, to ensure smooth initial engagement of the trailing end <NUM> of the plug by the friction stir welding tool, a portion of the trailing surface <NUM> may protrude below the surface <NUM> of the object <NUM>.

<FIG> is a photograph of a section of an opening <NUM> within an object <NUM> created by friction stir welding. For reference, the top surface of the object <NUM> is identified as an element <NUM>, while the side walls defining the opening <NUM> are identified as an element <NUM>. The opening <NUM> is shown to have a taper. The opening <NUM> also has spirally oriented ribs on the side walls <NUM>, which may be created due to rotation of the welding tool while it is removed from the object <NUM>.

<FIG> is a photograph of a top surface of an object <NUM> having two sets <NUM> and <NUM> of overlapping welds, wherein each of overlaps <NUM> and <NUM> includes a consumed plug. The overlap <NUM> was cross-sectioned in the Y direction, and the result is presented in <FIG>. The overlap <NUM> was cross-sectioned in the X direction, and the result is presented in <FIG> illustrate complete filing of the overlaps <NUM> and <NUM> and lack of voids in these areas.

An aircraft manufacturing and service method <NUM> shown in <FIG> and an aircraft <NUM> shown in <FIG> will now be described to better illustrate various features of processes and systems presented herein. During pre-production, aircraft manufacturing and service method <NUM> may include specification and design <NUM> of the aircraft and material procurement <NUM>. The production phase includes component and subassembly manufacturing <NUM> and system integration <NUM> of the aircraft. Thereafter, the aircraft may go through certification and delivery <NUM> in order to be placed in service <NUM>. While in service by a customer, the aircraft is scheduled for routine maintenance and service <NUM> (which may also include modification, reconfiguration, refurbishment, and so on). While the examples described herein relate generally to servicing of commercial aircraft, they may be practiced at other stages of the aircraft manufacturing and service method <NUM>.

Each of the processes of aircraft manufacturing and service method <NUM> may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include, without limitation, any number of aircraft manufacturers and major-system subcontractors; a third party may include, for example, without limitation, any number of vendors, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on.

As shown in <FIG>, aircraft <NUM> produced by aircraft manufacturing and service method <NUM> may include airframe <NUM>, interior <NUM>, and multiple systems <NUM> and interior <NUM>. Examples of systems <NUM> include one or more of propulsion system <NUM>, electrical system <NUM>, hydraulic system <NUM>, and environmental system <NUM>. Any number of other systems may be included in this example. Although an aircraft example is shown, the principles of the disclosure may be applied to other industries, such as the automotive industry.

Apparatus and methods embodied herein may be employed during any one or more of the stages of aircraft manufacturing and service method <NUM>. For example, without limitation, components or subassemblies corresponding to component and subassembly manufacturing <NUM> may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft is in service.

Also, various features described herein may be utilized during aircraft component and subassembly manufacturing <NUM> and/or during system integration <NUM>, which may expedite assembly of or reducing the cost of the aircraft. In some examples, these features may be utilized while the aircraft is in service, for example, during maintenance and service <NUM> of the aircraft.

Different examples and aspects of the apparatus and methods are disclosed herein that include a variety of components, features, and functionality. It should be understood that the various examples and aspects of the apparatus and methods disclosed herein may include any of the components, features, and functionality of any of the other examples and aspects of the apparatus and methods disclosed herein in any combination, and all of such possibilities are intended to be within the spirit and scope of the present disclosure.

Claim 1:
A method of installing a plug (<NUM>) into an opening (<NUM>) in an object (<NUM>), the plug (<NUM>) including a body (<NUM>), a first flange (<NUM>), and a second flange (<NUM>), wherein the first flange (<NUM>) is in contact with the body (<NUM>) and extends away from the body (<NUM>), and wherein the second flange (<NUM>) is in contact with the first flange (<NUM>) and extends away from the first flange (<NUM>) and away from the body (<NUM>),
and being characterised in that :
the second flange (<NUM>) is made of a different material than the first flange (<NUM>), and the different material that the second flange (<NUM>) is made of is softer than the material of the first flange (<NUM>), thereby allowing the second flange (<NUM>) to deform during installation of the plug (<NUM>) into the opening (<NUM>), while maintaining the first flange (<NUM>) substantially intact,
and in that the method includes the following step:
installing the plug (<NUM>) into the opening (<NUM>) to consolidate the plug (<NUM>) in the opening (<NUM>) and to rotationally and translationally secure the plug (<NUM>) in the opening (<NUM>), including urging the plug (<NUM>) into the opening (<NUM>), thereby deforming the second flange (<NUM>) toward the body (<NUM>).