US20150050440A1

US20150050440A1 - Multi-dimensional fiber composites and articles using the same

Info

Publication number: US20150050440A1
Application number: US14/519,600
Authority: US
Inventors: Tracy Albers; Joel Hawthorne; David Royal Loper; Malcolm Werner Kurt Rosenow
Original assignee: Fiber Materials Inc; Graftech International Holdings Inc
Current assignee: Fiber Materials Inc; Graftech International Holdings Inc
Priority date: 2013-04-26
Filing date: 2014-10-21
Publication date: 2015-02-19
Also published as: WO2014175977A1

Abstract

A composite down-hole tool for use in oil and gas wells includes plurality of fibers which extend along at least a first fiber plane and a second fiber plane. The first fiber plane and the second fiber plane are arranged perpendicular. A matrix material substantially fills the area between and around the plurality of fibers. The down-hole tool is spherical or cylindrical and substantially all of the plurality of fibers extend substantially straight and uninterrupted between opposed sides of the spherical or cylindrical shape down-hole tool.

Description

RELATED APPLICATIONS

This application is a continuation-in-part of International Application No. PCT/US14/30982, filed on Mar. 18, 2014, entitled “Multi-Dimensional Fiber Composites and Articles Using the Same,” which claims priority to US Provisional App. No. 61/816,307, filed on Apr. 26, 2013 and US Provisional App. No. 61/929,526, filed on Jan. 21, 2014 of which are incorporated herein by reference. The benefit of priority to the aforementioned applications is hereby claimed under at least 35 U.S.C. §365.

BACKGROUND

Fiber composite materials are widely used in a variety of applications. In particular, woven composites are increasingly useful due to exceptional strength and other properties that may be tailored to a particular application. However, prior art fiber composite materials may suffer from limitations including constrained thru-thickness, and strengths that are not adequate for certain extreme environments such as, for example, down-hole tools for use in the oil and gas industry. Accordingly, there is a need in the art for improved fiber composite materials and down-hole tools employing the same.

brief description

According to one aspect, a composite down-hole tool includes a plurality of fibers. The fibers extend along at least a first fiber plane and a second fiber plane. The first fiber plane and the second fiber plane are arranged perpendicular. A matrix material substantially fills the area between and around the plurality of fibers. The down-hole tool is spherical or cylindrical and substantially all of the plurality of fibers extend substantially straight and uninterrupted between opposed sides of the spherical or cylindrical shape down-hole tool.
Another embodiment disclosed herein includes a down-hole tool formed from a plurality of layers of fabric. Each layer may include fibers woven in at least two (2) directions (AKA dimensions). A matrix material may at least substantially fill an area between adjacent fibers and between adjacent fabric layers. The down-hole tool may have a spherical or cylindrical shape.

DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 is an isometric view of a three dimensional preform;

FIG. 2 is a front view of the preform of FIG. 1;

FIG. 3 is a larger isometric view of a three dimensional preform;

FIG. 4 is a top view of a four dimensional preform;

FIG. 5 is a side view of the preform of FIG. 4;

FIG. 6 is an isometric view of a the preform of FIG. 4;

FIG. 7 is a top view of a five dimensional preform;

FIG. 8 is a side view of the preform of FIG. 7;

FIG. 9 is an isometric view of the preform of FIG. 7;

FIG. 10 is a top view of an alternate four dimensional preform;

FIG. 11 is an isometric view of a cylindrical preform; and

FIG. 12 is an isometric view of a frac ball.

DETAILED DESCRIPTION

With reference to FIG. 1, a composite material is generally indicated by the numeral 10. The composite 10 includes a fiber reinforcement 12 and a matrix material (not shown for clarity). The fiber reinforcement 12 includes a plurality of fibers (either individual or bunched) 14 in distinct orientations. As used in the present disclosure a fiber plane 16 includes a plurality of individual fibers 14 aligned in a common plane and direction and having a generally constant center-to-center spacing. In a particularly advantageous embodiment, fibers in a fiber plane have a substantially equal center-to-center spacing throughout an entire fiber plane. As should also be appreciated, each composite 10 includes a plurality of each fiber plane 16 in a repeating stacked configuration.
Fibers 14 may include any number of fiber materials that provide structural reinforcement to the composite material. For example, fibers 14 may be carbon fibers and particularly PAN carbon fibers, glass fibers, aramid fibers (e.g. Kevlar® produced by DuPont), PEEK fibers (polyether ether ketone), PPS fibers (polyphenylene sulfide), PEN fibers (polyethylene naphalate), basalt fibers and combinations thereof. Fiber 14 is not limited to any particular tow size. A range of tow sizes of particular interest may range from about 1K to about 30K. Examples of particular tow sizes under consideration include 1K, 3K, 5K, 8K, 12K, 15K, 18K, 21K, 24K and 30K. The various tow sizes may be used independently of one another in any particular embodiment or in any combination thereof in any particular embodiment.
The matrix material fills substantially the entire area between and around the fibers in composite material 10, 100, 200, 300, and 400. Matrix material must be flowable to enable the impregnation of the fiber planes. The matrix material is selected based on the desired performance, operating temperature, compressive strength, processing characteristics, chemical stability, porosity, and density. Exemplary matrix materials include epoxies, polyester resin, vinyl ester, cyanate ester, polyimides, phenolic, engineering thermal plastics, PEEK (polyetheretherketone), PPS (polyphenylene sulfide), PS (polysufone), Torlon® (polyamide-imide), Nylon6/6, Nylon 11 benzoxazine, ceramic, pitch and combinations thereof. Matrix material advantageously includes a room temperature compressive strength of at least 3.0 kPsi, still more advantageously at least 5.0 kPsi, still more advantageously at least 15 kPsi, and still more advantageously at least 20 kPsi. In other embodiments, the matrix material includes a compressive strength of from between about 5 kPsi and about 25 kPsi. In further embodiments, the matrix material includes a compressive strength of from between about 10 kPsi and about 20 kPsi. The amount of matrix material in composite 14 may vary from embodiment to embodiment as desired.
Optionally the matrix material may include a reinforcement. Examples of the reinforcement include multi-walled carbon nanotubes, single walled carbon nanotubes, graphene particles and combinations thereof. The amount of reinforcement included in the matrix may include up to ten percent (10%) by weight of the resin (“bwr”), no more than five percent (5%) bwr, no more than three percent (3%) bwr, no more than two percent (2%) bwr, or no more than one percent (1%) bwr.
The down-hole tool, to be discussed in greater detail below, advantageously includes a matrix material having a temperature capability of at least about 200° F., and more advantageously at least about 300° F., and even further more advantageously at least about 350° F. By temperature capability, it is meant that the matrix material may be heated to the above temperature without melting or otherwise becoming substantially structurally degraded during the required service period. In particular, epoxies and polyimide matrix materials exhibit particularly advantageous characteristics for down-hole tools.
Refer again to the composite preform of FIG. 1, wherein the reference directions x, y and z are shown. As shall be discussed in greater detail below, the fiber composition of the composite preform of FIG. 1 is referred to as three dimensional, because the fibers extend in three distinct fiber directions. Thus, for example, the composite material shown in FIG. 1 includes a first fiber orientation 14 a, a second fiber orientation 14 b and a third fiber orientation 14 c. The fibers 14 a lying on the same plane form a first fiber plane 16 a, the fibers 14 b lying on the same plane form a second fiber plane 16 b and the fibers 14 c lying on the same plane form a third fiber plane 16 c. As can be seen, first fiber plane 16 a and 16 b are parallel to the x-y plane and have a fiber direction offset from each other by 90 degrees. The fibers 14 c, forming third fiber plane 16 c, are oriented perpendicular to the x-y plane.
Within each fiber plane, individual fibers are oriented in the same direction and on the same plane and may have a center-to-center spacing from between about 0.035 inches to about 0.500 inches. In further embodiments, the center-to-center spacing may be from between about 0.069 inches to about 0.2 inches. The first fiber plane 16 a and second fiber plane 16 b are arranged parallel to the X-Y plane and in the composite material 10 are layered in an alternating stacked arrangement. Third fiber plane 16 c transects first and second fiber planes 16 a and 16 b. In one embodiment, an aperture 17 is formed by adjacent fibers in fiber plane 16 a and over-laid adjacent fibers of fiber plane 16 b, and each aperture 17 advantageously receives a fiber from fiber plane 16 c there through. As can be seen, composite material 10 includes a plurality of third fiber planes 16 c, positioned in a stacked arrangement.
Advantageously, fiber planes 16 a and 16 b are spaced at a substantially constant distance from each other. In other embodiments, the fibers 14 a and 14 b forming fiber planes 16 a and 16 b are layered and in direct contact. For purposes of the present disclosure, two adjoining fiber planes 16 a and 16 b are referred to as a fiber layer 20. In this or other embodiments, the number of layers per inch (hereinafter LPI) may be from between about 1 LPI to about 50. In further embodiments, the LPI may be from between about 5.0 and about 15. In still further embodiments, the LPI may be from between about 8.0 and about 35. The composite material includes a plurality of repeating fiber planes distributed throughout the entire article. For example, first and second fiber planes 16 a and 16 b repeat in a stacked arrangement in the z direction for the entire height of the composite material. Similarly, the third fiber plane 16 c repeats in the y direction for the entire width of the composite material.
As shown if FIGS. 1-3, fibers 14 of composite material 10 extend substantially straight for the entire length of the composite material 10. In the illustrated embodiment , the fiber weave does not include any crimps and are not interwoven to form a sine or wave shape. Further, advantageously at least 95 percent, more advantageously at least 99 percent, and still more advantageously substantially all of fibers 14 extend substantially straight and uninterrupted between opposed sides of the composite material. Thus, in this manner no fiber loops or crimps are included in the article. Likewise, the uniform composition with uninterrupted fibers improves strength and structural integrity of the composite material, and thus any subsequently produced article.
In a particular embodiment, the fibers of composite 10 may be oriented in a two dimensions (“2-D”), three dimensions (“3-D”) or more than 3-D.
With reference to FIGS. 4-6, a composite material 100 is shown and generally indicated by the numeral 100. As shall be discussed in greater detail below, the fiber composition of the composite material of FIGS. 4-6 is referred to as four dimensional, because the fibers extend in four distinct directions. Thus, the composite material shown in FIG. 4 includes a first fiber orientation 114 a, a second fiber orientation 114 b, a third fiber orientation 114 c and a fourth fiber orientation 114 d. As can be seen, first fibers 114 a lying on the same plane form first fiber plane 116 a, second fibers 114 b lying on the same plane form second fiber plane 116 b, third fibers 114 c lying on the same plane form a third fiber plane 116 c, and fourth fibers 114 d lying on the same plane form a fourth fiber plane 116 d. First, second and third fiber orientations 114 a, 114 b and 114 c are parallel to the x-y plane and have a fiber direction offset from each other by 60 degrees respectively. The fourth fibers 114 d forming fourth fiber plane 116 d are oriented perpendicular to the x-y plane. Within each fiber plane, individual fibers are oriented on the same plane and direction and may have a center-to-center spacing from between about 0.042 inches to about 0.500 inches. In further embodiments, the center-to-center spacing may be from between about 0.062 inches to about 0.200 inches. The first fiber plane 116 a, second fiber 116 b plane and third fiber plane 116 c are arranged parallel to the X-Y plane and are positioned in an alternating stacked arrangement in the z direction. Fourth fiber plane 116 d transects first, second, and third fiber planes 116 a, 116 b and 116 c. In one embodiment, an aperture 117 is formed by adjacent fibers in the three over-laid fiber planes 116 a, 116 b and 116 c. Advantageously, each aperture 117 receives a fiber from a fiber plane 116 d there through.
Advantageously, fiber planes 116 a, 116 b, and 116 c are spaced at a substantially constant distance from each other. In this or other embodiments, the fibers 114 a, 114 b and 114 c of adjacent fiber planes 116 a, 116 b and 116 c are layered and in direct contact. For purposes of the present disclosure, a set of three adjoining fiber planes 116 a, 116 b and 116 c parallel to the X-Y plane are referred to as fiber layer 120. In this or other embodiments, the number of layers per inch (hereinafter LPI) may be from between about 1 LPI to about 30 LPI. In further embodiments, the LPI may be from between about 5.0 and about 15. In still further embodiments, the LPI may be from between about 4.0 and about 12. The composite material 100 includes a plurality of repeating fiber planes distributed throughout the entire article. For example, first, second and third fiber planes 116 a, 116 b, and 116 c repeat in a stacked arrangement in the z direction for the entire height of the composite material. Similarly, the fourth fiber plane 116 d repeats in the y direction for the entire width of the composite material.
As shown if FIGS. 4-6, fibers 114 of composite material 100 extend substantially straight for the entire length of the composite material 100. In other words, the fiber weave does not include any crimps and are not interwoven to form a sine or wave shape. Further, advantageously at least 95 percent, more advantageously at least 99 percent, and still more advantageously substantially all of fibers 114 extend uninterrupted between opposed sides of the composite material. Thus, in this manner no fiber loops or crimps are included in the article. Likewise, the uniform composition with uninterrupted fibers improves strength and structural integrity of the composite material, and thus any subsequently produced article.
With reference now to FIGS. 7-9, a preform composite material is shown and generally indicated by the numeral 200. As shall be discussed in greater detail below, the fiber composition of the composite material of FIG. 7-9 is referred to as five dimensional, because the fibers extend in five distinct directions. Thus, the composite material includes a first fiber orientation 214 a, a second fiber orientation 214 b, a third fiber orientation 214 c, a fourth fiber orientation 214 d, and a fifth fiber orientation 214 e. As can be seen, first fiber orientation 214 a lying on the same plane forms a first fiber plane 216 a, second fiber orientation 214 b lying on the same plane forms a second fiber plane 216 b, third fiber orientation 214 c laying on the same plane forms a third fiber plane 216 c and fourth fiber orientation 214 d laying on the same plane forms a fourth fiber plane 216 d. Fibers 214 a, 214 b, 214 c and 214 d are parallel to the x-y plane and have a fiber direction offset from each other by 60 degrees respectively. Fifth fiber orientation 214 e laying on the same plane forms a fifth fiber plane 216 e and is oriented perpendicular to the x-y plane.
Within each fiber plane, individual fibers are oriented on the same plane and direction and may have a center-to-center spacing from between about 0.042 inches to about 0.500 inches. In other embodiments, the center-to-center spacing may be from between about 0.42 inches to about 0.200 inches. The first fiber plane 216 a, second fiber 216 b plane, third fiber plane 216 c and fourth fiber plane 216 d are arranged parallel to the X-Y plane and are positioned in a repeating alternating pattern. Fifth fiber plane 216 e transects first, second, third and fourth fiber planes 216 a, 216 b, 216 c and 216 d. In one embodiment, an aperture 217 is formed by adjacent fibers in the four over-laid fiber planes fiber plane 216 a, 216 b, 216 c and 216 d. Advantageously, each aperture 217 receives a fiber from a fiber plane 216 e there through.
Advantageously, fiber planes 216 a, 216 b, 216 c and 216 d are spaced at a substantially constant distance from each other. In other embodiments, the fibers 214 a, 214 b, 214 c and 214 d are stacked adjacent to each other and in direct contact. For purposes of the present disclosure, four adjoining fiber planes 216 a, 216 b, 216 c and 216 d are parallel to the X-Y plane and are referred to as a fiber layer 220. In this or other embodiments, the number of layers per inch (hereinafter LPI) may be from between about 1 LPI to about 30 LPI. In other embodiments, the number of layers per inch may be from between about 4 LPI and about 12 LPI. The composite material 200 includes a plurality of repeating fiber planes distributed throughout the entire article. For example, first, second, third and fourth fiber planes 216 a, 216 b, 216 c and 216 d repeat in a stacked arrangement in the z direction for the entire height of the composite material. Similarly, the fifth fiber plane 116 e repeats in the y direction for the entire width of the composite material.
As shown if FIGS. 7-9, fibers 214 of composite material 200 extend substantially straight for the entire length of the composite material 200. In other words, the fiber weave does not include any crimps and are not interwoven to form a sine or wave shape. Further, advantageously at least 95 percent, more advantageously at least 99 percent, and still more advantageously substantially all of fibers 214 extend uninterrupted between opposed sides of the composite material. Thus, in this manner no fiber loops or crimps are included in the article. Likewise, the uniform composition with uninterrupted fibers improves strength and structural integrity of the composite material, and thus any subsequently produced article.
With reference now to FIG. 10, a composite material is shown and generally indicated by the numeral 300. As shall be discussed in greater detail below, the fiber composition of the composite material of FIG. 10 is referred to as four dimensional, because the fibers extend in four distinct directions. However, the composite 300 differs from the composite 100 in that each of the first fiber plane 316 a formed by fibers 314 a, second fiber plane 316 b formed by fibers 314 b, third fiber plane 316 c formed by fibers 314 c and fourth fiber plane 316 d formed by fibers 314 d (appearing to extend out of the paper) extend in a distinct direction and none of the fiber planes are parallel to another fiber plane. Within each fiber plane, individual fibers are oriented on the same plane and direction and may have a repeating center-to-center spacing from between about 0.042 inches to about 0.500 inches. In other embodiments, the center-to-center spacing may be from between about 0.42 inches to about 0.200 inches. Because of the unaligned nature of the composite material 300, each fiber layer will transect the other three fiber layers. The composite material 300 includes a plurality of repeating fiber planes distributed throughout the entire article. Specifically, each of fiber planes 316 a, 316 b, 316 c, and 316 d repeats in a direction perpendicular to the respective plane for the entire width/length of the composite material.
As shown in FIG. 10, fibers 314 of preform composite 300 extend substantially straight for the entire length of the preform composite 300. In other words, the fiber weave does not include any crimps and are not interwoven to form a sine or wave shape. Further, advantageously at least 95 percent, more advantageously at least 99 percent, and still more advantageously substantially all of fibers 314 extend uninterrupted between opposed sides of the composite material. Thus, in this manner no fiber loops or crimps are included in the article. The uniform composition with uninterrupted fibers improves strength and structural integrity of the composite and likewise any subsequently produced article.
The three, four and five dimensional composite materials described hereinabove may be produced in considerably larger dimensions than traditional woven composites. Advantageously, the composite materials may be produced having a z-direction height of at least 12.0 inches, more advantageously at least 18 inches, and still more advantageously at least 24 inches tall and still more advantageously at least 36 inches tall. In further embodiments, the z-direction height may be from between about 6 inches and about 36 inches. In this or other embodiments, the x and y direction lengths may be greater than at least 4 inches, still more advantageously at least 12 inches and still more advantageously at least 24 inches. In this or other embodiments, the x and y direction lengths may be from between about 12 inches and about 24 inches.
Compressive strength of the composite material described here in above is principally dependent on fiber volume and direction. In one embodiment, the composite material compressive strength may be determined based on a compressive strength factor times the fiber volume extending in the direction of measurement. Thus, for example, for a composite material having 10 percent fiber volume extending in the z-direction, the compressive strength may be determined in the z-direction by multiplying 0.10 times a compressive strength factor for the selected fiber or reinforcement. In one embodiment, the compressive strength factor is from between about 170 ksi and about 530 ksi. In still other embodiments the compressive strength factor is from between about 250 ksi and about 400 ksi. In still other embodiments, the compressive strength factor is greater than about 170 ksi. In other embodiments the compressive strength factor is greater than about 250 ksi. And in still further embodiments, the compressive strength factor is greater than about 380 ksi.
Tensile strength of the composite material described hereinabove is dependent on fiber volume and direction. In one embodiment, the composite material tensile strength may be determined based on a tensile strength factor times the fiber volume extending in the direction of measurement. Thus, for example, for a composite material having 10 percent fiber volume extending in the z-direction the tensile strength may be determined in the z-direction by multiplying 0.10 times a tensile strength factor. In one embodiment, the tensile strength factor is from between about 220 ksi and about 690 ksi. In still other embodiments the tensile strength factor is from between about 300 ksi and about 550 ksi. In still other embodiments, the tensile strength factor is greater than about 220 ksi. In other embodiments the tensile strength factor is greater than about 290 ksi.
With the following information a composites engineer of ordinary skill in the art would be able to determine the compressive strength factor or the tensile strength factor for the composite material: (1) type of fiber; (2) fiber properties e.g., compressive strength, tensile strength, shear strength, and modulus; (3) matrix material; (4) fiber volume; and (5) the fabric is “straight yarn.”
With reference now to FIG. 11, a composite material is shown and generally indicated by the numeral 400. Composite material 400 differs from the above described composites in that not all fibers are straight and not all fibers extend from between opposed sides of the material. Composite 400 is generally cylindrical shaped and includes circumferentially extending fibers 414, radially extending fibers 414 b, and axially extending fibers 414 c. Individual layer planes 416 a of circumferentially extending fibers 414 a lay on the same plane and grow radially larger from an inner radial surface to the outer radial surface of composite 400. Individual layer planes 416 b of radially extending fibers 414 b lay on the same plane and extend radially outward and are angularly offset about the diameter of the cylinder.
For purposes of the present disclosure, one circumferentially extending fiber layer 416 a and radially extending fiber layer 416 b are referred to as a fiber layer 420. In this or other embodiments, the number of layers per inch (hereinafter LPI) may be from between about 0.5 LPI to about 30 LPI. Center-to-center spacing of circumferentially extending fibers 416 a (in the radial direction) may be from between about 0.025″ to about 0.500″. More advantageously, center-to-center spacing of the circumferentially extending fibers 416 a may be from between about 0.065″ and about 0.330″. The center-to-center spacing of radially extending fibers 416 b (in the circumferential direction) may be from between 0.035″ and about 0.700″. In other embodiments, the center-to-center spacing of radially extending fibers (in the circumferential direction) may be from between about 0.065″ and about 0.330″. Advantageously, the layers per inch are substantially constant through the axial length of the preform 400. However, it should be appreciated that the center-to-center spacing of the radially extending fibers is dependent on the radial distance from the centerline of the cylinder. In other words, the further from the centerline of the cylinder, the larger the center-to-center spacing of the radially extending fibers.
The circumferential fiber plane 416 a and radial fiber plane 416 b are arranged parallel to the X-Y plane and are positioned in an alternating stacked arrangement in the z direction. Axially extending fibers 414 c transect the radial and circumferential fiber planes 416 a and 416 b. In one embodiment, an aperture 417 is formed by adjacent fibers in the two over-laid fiber planes 416 a and 416 b. Advantageously, each aperture 117 receives at least one axially extending fiber 416 c there through. The composite material 400 includes a plurality of repeating fiber planes distributed throughout the entire article. For example, circumferential fiber plane 416 a and radial fiber plane 416 b repeat in a stacked arrangement in the z direction for the entire height of the composite material. Similarly, the axially extending fibers 414 c are repeat in the radial and circumferential directions, advantageously positioned between each adjacent circumferential fiber 414 a and between each adjacent radial fiber 414 b.
The composite materials described herein above may be constructed with fiber volumes, as defined by the relationship between actual fiber volume and overall part volume, from between about 15% to about 55%. In further embodiments, and as may be particularly advantageous for down-hole tools, the fiber volume may be from between about 30% and about 43%. In one embodiment, the fiber volume for each fiber direction is substantially the equivalent. In this embodiment, the composite material includes at least 5 percent fiber volume, more advantageously at least 8 percent fiber volume, and still more advantageously at least 10 percent fiber volume in each fiber direction. In a particularly preferred embodiment for the down-hole tool described herein below, a 3 dimensional composite includes from between about 5 and about 15 percent fiber volume in each of the x, y and z direction, and more advantageously from between about 8 and about 12 percent fiber volume in each of the x, y and z direction. In other embodiments, the fiber volumes for one or more of the fiber directions may be different, resulting in varied physical properties depending on orientation of the composite material.
Advantageously, the density of the composite material may be from between about 0.90 g/cc to about 2.00 g/cc. In a further embodiment, and one particularly advantageous for a down-hole tool, the overall composite density may be from between about 1.20 g/cc to about 1.8 g/cc. In further embodiments, the composite material has a density of less than about 1.8 g/cc, and more advantageously less than about 1.5 g/cc, and still more advantageously less than about 1.2 g/cc.
It should be appreciated that, for each of the above composite materials, in one embodiment a single fiber type is used for all fiber planes. In another embodiment, one or more of the fiber planes may include different fiber types from the other fiber planes. For example, the fibers in a fiber plane oriented along a z-axis may include a first type of fiber and the fiber planes oriented parallel to an x-y plane may include a second type of fiber. In still a further embodiment, each fiber plane may include a different fiber type.
With reference now to FIG. 12 a down-hole tool, is generally indicated by the numeral 500. Down-hole tool may be made from any of the above described composite materials.
Down-hole tool 500 is particularly suitable for, and adapted for use, in underground oil and gas applications. In one embodiment, down-hole tool is a frac ball which is sized to be dropped or pumped into an oil or gas well to be received in a seat (not shown). In this manner, sections of the well may be sealed off from other sections so that certain treatments or functions may be performed. Accordingly, to facilitate sealing, down-hole tool 500 is substantially spherical. In other embodiments, the down-hole tool 500 is substantially ovoid or egg shaped. In still further embodiments, down-hole tool is generally cylindrical in shape. In an additional embodiment, the down-hole tool 500 may have an oval cross section. Down-hole tool 500 may have a diameter of from between about 0.5 inches to about 8.0 inches. If down-hole tool is egg or ovoid shaped, the down-hole tool may have an axial length from between about 2.0 inches to about 12.0 inches. If down-hole tool is cylindrical shaped, the diameter may be at least two inches, in other embodiments at least 4 inches, and in still other embodiments at least 6 inches. If down-hole tool is a cylindrical shape, the axial length may be at least 6 inches, in other embodiments at least 12 inches, and in still other embodiments at least 24 inches.
Down-hole tool 500 may advantageously be made of any of the above described composite materials. In one particular embodiment, down-hole tool 500 is sphere shaped, includes a 3 dimensional fiber structure as described hereinabove. Therefore, the tool 500 and includes fibers extending straight and uninterrupted to opposed sides of the tool along at least two perpendicular planes. Advantageously, the two perpendicular planes transect the largest diameter of the down-hole tool. In one embodiment, the down-hole tool includes at least one of PAN based carbon fibers and/or E and/or S glass fibers and includes epoxy or polyimide as the matrix material. Down-hole tool 500 advantageously withstands well pressures of greater than 10,000 psi, still more advantageously greater than 12,000 psi, and still more advantageously greater than 15,000 psi without being extruded into the seat or otherwise failing.
Another embodiment disclosed herein includes a down-hole tool formed from a plurality of layers of fabric. Each layer may include fibers woven in at least two (2) directions (AKA dimensions). A matrix material may at least substantially fill an area between adjacent fibers and between adjacent fabric layers. The down-hole tool may have a spherical or cylindrical shape. Just to avoid any doubt, the above description regarding the matrix material and the reinforcement, are equally applicable to this embodiment also.
In a particular embodiment, the fabric layers may be constructed from fibers having more than one sized fiber tow. For example, the size of fiber tow used to make one or more fabric layers of the composite article may range from 1000 to 30000. One preferred upper end sized fiber tow is 24000 (“24K”). In a different embodiment, each fabric layer is made from one sized fiber tow, but adjacent fiber layers are not made from the same sized tow.
The fabric layer is not limited to one style of weave. Individual fabric layers may be constructed of at least one of the following weave styles: twill style weave, a plain weave or a unidirectional weave. The plurality of fabric layers may all have the same weave style, a different weave style or any combination thereof.
The composite article may be constructed from a billet. The billet may be formed from a plurality of woven fabric layers laid one on top of the other. If so desired the adjacent individual fabric layers maybe laid parallel to one another, perpendicular to one another, thereby creating an isotropic billet. In an different embodiment, the adjacent fabric layers may be oriented about sixty 60°) degrees (at least 50° to no more than 70°) from each other.
In one advantageous embodiment of the above graphite article, the article will have a water absorption (AKA moisture absorption) of less than three (3%) percent, preferably less than two (2%) percent, more preferably less than one (1%) percent and even more preferably less than half (0.5%) percent. ASTM standard D 570 may be used to determine the water absorption exhibited by the graphite article.
The above description is intended to enable the person skilled in the art to practice the invention. It is not intended to detail all the possible variations and modifications that will become apparent to the skilled worker upon reading the description. It is intended, however, that all such modifications and variations be included within the scope of the invention that is defined by the following claims. Thus, although there have been described particular embodiments of the present invention of a new and useful fiber composite, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims.

Claims

We claim:

1. A composite down-hole tool comprising:

a plurality of fibers, said fibers extending along at least a first fiber plane and a second fiber plane, said first fiber plane and said second fiber plane being arranged perpendicular;

a matrix material substantially filling the area between and around the plurality of fibers; and

wherein the down-hole tool is spherical or cylindrical and substantially all of said plurality of fibers extend substantially straight and uninterrupted between opposed sides of the spherical or cylindrical shape down-hole tool.

2. The down-hole tool according to claim 1 having a density less than about 1.8 g/cc.

3. The down-hole tool according to claim 1 having a density of from between about 1.0 g/cc and about 1.8 g/cc.

4. The down-hole tool according to claim 1 having uniform compressive strength.

5. The down-hole tool according to claim 1 wherein the compressive strength of the down-hole tool is different in the direction of said first fiber plane from said second fiber plane.

6. The down-hole tool according to claim 1 further comprising a third fiber plane arranged parallel to said first fiber plane and having a third fiber direction, said first fiber plane having a first fiber direction being 90 degrees offset from said third fiber direction.

7. The down-hole tool according to claim 1 further comprising a third fiber plane and a fourth fiber plane arranged parallel to said first fiber plane, said first fiber plane having a first fiber direction, said second fiber plane having a second fiber direction, said third fiber plan having a third fiber direction and said fourth fiber plane having a fourth fiber direction, said first fiber direction, being offset by 60 degrees from said third fiber direction and said fourth fiber direction being offset by 60 degrees from said third fiber direction.

8. The down-hole tool according to claim 1 having a fiber volume from between about 15% and about 55%.

9. The down-hole tool according to claim 1 having a fiber volume from between about 30% and about 40%.

10. The down-hole tool according to claim 1 having a compressive strength factor greater than about 80 ksi.

11. The down-hole tool according to claim 1 having a tensile strength factor greater than about 220 ksi.

12. The down-hole tool according to claim 1 wherein said plurality of fibers include one or more of PAN based carbon fibers, E glass fibers or S glass fibers.

13. The down-hole tool according to claim 1 wherein said matrix comprises epoxy or polyimide.

14. The down-hole tool according to claim 1 wherein said plurality of fibers includes radially extending fibers, circumferentially extending fibers and axially extending fibers.

15. The down-hole tool according to claim 1 having a diameter of from between about 0.5 to about 8.0 inches.

16. A composite down-hole tool comprising

a plurality of layers of fabric each layer comprises a plurality of fibers woven in two dimensions;

a matrix material substantially filling an area between adjacent fibers and between adjacent fabric layers; and

wherein the down-hole tool having a spherical or cylindrical shape.

17. The tool of claim 18 wherein the fabric layers constructed from more than one sized fiber tows, size of the tows range from 1000 to 24000.

18. The tool of claim 18 wherein the matrix material comprises at least one of an epoxy, phenolic, polyimide, pitch and combinations thereof.

19. The tool of claim 18 wherein the matrix material comprises a reinforcement, the reinforcement comprises at least one of single walled carbon nanotube, multi-walled carbon nanotubes and combinations thereof.

20. The tool of claim 21 wherein the matrix material comprises no more than five percent by weight of the resin.

21. The tool of claim 18 wherein the fabric layer may comprise one of a twill style weave, a plain weave or a unidirectional weave.