Composite interwoven gas containment assembly

Abstract

A pressure vessel is provided having a structural shell formed by winding filaments onto a substantially cylindrical former. The structural shell has a first filament and a second filament. The first filament comprises a first material. The first filament is wound in a primary hoop direction around the former. The second filament comprises a second material. The second material is different from the first material. The second filament is wound in a primary helical direction around the former. The first filament and the second filament are interwoven into layers on the former.

Description

[Technical field]

[0001] INCORPORATION BY REFERENCE OF ANY PRIORITY APPLICATION Any application for which a foreign or domestic priority claim is identified in an Application Data Sheet filed with this application is incorporated herein by reference under 37 CFR § 1.57. For example, this application claims priority to U.S. Provisional Patent Application No. 63 / 201667, filed May 7, 2021, which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to gas cylinder assemblies having liners and reinforcement structures for providing high pressure rated gas cylinders, low cost durable gas cylinders and / or other gas containment structures. [Background technology]

[0003] Gas cylinders can be configured as pressure vessels and as fuel tanks for compressed natural gas (CNG), and can also be used to store hydrogen in transportation applications. Such tanks can be categorized into four different types. Type 3 and Type 4 tank designs use metal and polymer liners, respectively, and fiber reinforcement. The fiber reinforcement includes a filament wound layer to provide structural reinforcement. Unlike other tank types, Type 4 tanks are not subject to corrosion, are lighter in weight per unit volume when stored, and are less expensive to manufacture.

[0004] Winding fiber reinforcement filaments onto a liner is a complex process. When the tank is pressurized, the loads in the radial direction are much greater than the loads in the axial direction. As a result, the fibers must provide more reinforcement in the radial direction than they provide in the axial direction. The difference in reinforcement is obtained by providing one winding pattern of the fibers in the central cylindrical section of the tank and a different winding pattern over the domed ends of the tank.

[0005] To provide these winding patterns, conventional tank fabrication involves transitioning from a center section winding pattern to a domed end winding pattern. In one technique, the transition is accomplished by cutting the fiber filament that is being wound for radial reinforcement at the end of the center section. Winding of the end section pattern can then be initiated by connecting the free end of the fiber filament to the tank, reorienting the fiber filament, and winding the end pattern around the tank. This approach is not practical in mass production. In another technique, the transition is accomplished by slowly leading the fiber angle from a high angle in the center section to a lower angle in the end section pattern, within the limits of friction. However, this approach involves winding more material than is structurally required, which increases weight, thickness / diameter, winding time, and cost. Summary of the Invention [Problem to be solved by the invention]

[0006] Improved fiber winding techniques are needed in the production of gas cylinders, such as pressure vessels and fuel tanks, and other gas containment assemblies, including pipes, to provide a process suitable for practical mass production and to reduce production compromises that may arise due to limitations in winding pattern transfer. Improvements may be achieved by winding hoop and helical strands simultaneously to obtain an interwoven structure. This approach may provide improved reinforcement per unit weight using the same or different materials for the hoop and helical strands. [Means for solving the problem]

[0007] In some applications, a winding device may be provided that allows for independent application of hoop and helical strands to facilitate interweaving. Preferably, the winding device can facilitate simultaneous winding with different materials and / or different compositions of materials to provide an interwoven structure with higher strength where needed and less excess fiber where less strength is sufficient.

[0008] In one example, a gas containment assembly, such as a pipe or pressure vessel, may include a liner reinforced by a single three-dimensional woven layer. The inner surface of the single three-dimensional woven layer may be in direct contact with the outer surface of the liner. The outer surface of the single three-dimensional woven layer may form the outer surface of the fully formed tank. In some cases, the outer surface of the fully formed tank is also painted or otherwise finished, although in such cases, no additional structural layers are required.

[0009] The method of interweaving the primary hoop strands and primary helical strands can provide a composite structure without separate boundaries between separate layers formed of materials of different stiffness or compositions of materials of different stiffness, which is believed to be much more durable than layered structures with respect to delamination and / or at certain impact angles or directions of impact forces.

[0010] In another embodiment, a method is provided in which a form (e.g., a metal or polymer liner, a pipe liner, a mandrel, and / or a removable form) is attached to a spindle. The form is rotated using the spindle. While the form is rotating, a first filament of a first material is wound in a primary hoop direction. While the first filament is being wound, a second filament is simultaneously wound in a primary helical direction. The simultaneous winding of the first and second filaments provides an interwoven structure that is disposed around the form and reinforces the form. If the form is a liner, the form can be incorporated into a finished product, for example, a pressure vessel or pipe assembly. In some methods, the form is removable such that an inner layer of filaments forms a free surface, e.g., an inside, of the structure.

[0011] In some methods, the winding of the first filament and the second filament are independently controlled by a first carriage having a first eye in a first configuration (e.g., at an angle relative to a meridian of the liner) and a carriage having a second eye in a second configuration (e.g., at an angle relative to a meridian of the liner). The first carriage and the second carriage can be controlled to create a three-dimensional structure over multiple passes over the liner or other form, the three-dimensional structure interwoven in each pass and without a separate strained boundary layer portion of the reinforcing layer applied by subsequent passes.

[0012] In some methods, the steps of winding a first filament and simultaneously winding a second filament are performed with at least one of the first filament and the second filament being continuous, for example, from an inner boundary of the complete reinforced structure to an outer boundary of the complete reinforced structure, where a complete reinforced structure is one that is sufficiently strong for the application and does not require the inclusion of a surface finish, paint, or other layer on the outside of the reinforced structure.

[0013] In some methods, winding the first filament includes adjusting a first eye of the winding device over a first angle range relative to the meridian of the liner (or, more generally, the mold), and simultaneously winding the second filament includes adjusting a second eye of the winding device over a second angle range relative to the meridian of the liner (or, more generally, the mold). In some approaches, the first angle range does not overlap with the second angle range. The first angle range may correspond to a primary hoop direction, and the second angle range corresponds to a primary helical direction. The first angle range may be between about 80 degrees and about 100 degrees. The second angle range may be between about 20 degrees and about -20 degrees.

[0014] In one embodiment, a gas containment assembly such as a pressure vessel, or more generally a pipe, is provided having a structural shell formed by filament winding on a substantially cylindrical former. The former can be a lightweight, e.g., polymeric, liner in some embodiments. The former can be a metal liner in some embodiments. The former can be removable in some embodiments. The structural shell has a first filament and a second filament. The first filament includes a first material. The first filament is wound in a primary hoop direction around the former. The second filament includes a second material. The second material is different from the first material. The second filament is wound in a primary helical direction around the former. The first filament and the second filament are interwoven into layers on the former.

[0015] In another embodiment, a gas containment vessel assembly, such as a pressure vessel, or more generally a pipe assembly, is provided that includes a substantially cylindrical former (e.g., a polymer liner, a lightweight liner, a lightweight polymer liner, a metal liner, a pipe liner, a mandrel, and / or a removable former), a first filament, and a second filament. The first filament is wound in a primary hoop direction around the former. The second filament is wound in a primary helical direction around the former. The first filament and the second filament are woven onto the former such that a first portion of the first filament is disposed above the second filament and a second portion of the first filament is disposed below the second filament. As used herein, one filament is under the other filament if its length is between the other filament and the liner in a radial direction of the pressure vessel.

[0016] The first filament and the second filament may be of the same material. When the first filament and the second filament are of the same material, the composition of the first filament and the second filament may be the same. The first filament and the second filament may be of the same material, but the first filament and the second filament may have different material properties. For example, the first filament and the second filament may include the same material, but the first filament may be configured with greater strength. The first filament and the second filament may include different materials, such as a carbon reinforced filament and a glass reinforced filament.

[0017] The characteristics of the present invention can be understood when the following detailed description is read in conjunction with the accompanying schematic drawings, which are given for illustrative purposes only and include the following figures: [Brief description of the drawings]

[0018] [Figure 1]1A-1C illustrate a portion of a process for forming an improved gas cylinder, such as a pressure vessel or fuel tank, using multiple winding eyes on a two-carriage winding apparatus. [Diagram 2] 2 is a schematic diagram further illustrating the winding device of FIG. 1 and a method of winding a filament using the winding device. [Figure 3A] FIG. 2 is a schematic diagram of the gas cylinder seen in FIG. 1 with a portion of the woven structure shown in detail. [Figure 3B] FIG. 2 is a schematic diagram of the gas cylinder seen in FIG. 1 with another portion of the woven structure shown in detail. [Figure 3C] FIG. 2 is a schematic diagram of the gas cylinder seen in FIG. 1 with another portion of the woven structure shown in detail. [Figure 3D] FIG. 2 is a schematic diagram of the gas cylinder seen in FIG. 1 with another portion of the woven structure shown in detail. [Figure 4] FIG. 3E is a cross-sectional view of a portion of a gas cylinder produced by the winding apparatus and method shown in FIGS. 1-3D. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Although the present specification describes specific details of various embodiments, it will be understood that the present specification is merely for illustration and should not be construed as limiting in any way. Moreover, various applications of such embodiments and modifications thereof that may occur to those skilled in the art are also included in the general concepts described herein. Any and all features described herein, and any and all combinations of two or more of such features, are included within the scope of the present invention, so long as the features included in such combinations are not mutually inconsistent.

[0020] The present application discloses novel gas cylinders, as well as methods and apparatus for making such gas cylinders. As used herein, "cylinder" is a term that includes storage tanks, pressure vessels, and other containers that may be used to store gas, and is not necessarily limited to a particular shape, such as a right cylinder, and / or has a fixed or invariant circular shape in cross section. The novel apparatus and method create an interwoven structure of a first fiber wound in a first direction and a second fiber wound in a second direction. The winding process results in a three-dimensional structure of interwoven fibers that avoids distinct boundary layers within the structure, particularly boundary layers with respect to stiffness. The three-dimensional structure of interwoven fibers can be formed continuously, for example, with continuous strands of fibers, to avoid cutting or lodging fibers for transitions between layers. By eliminating such boundary layers, the reinforced structure avoids certain failure modes while at the same time obtaining, in some embodiments, a high pressure rating, in some embodiments, a high durability, and in some embodiments, both a high pressure rating and a high durability.

[0021] FIG. 1 shows a winding apparatus 50 and a pressure vessel 100 being made by the winding apparatus 50. The winding apparatus 50 is a two-carriage apparatus. The disclosure is not limited to two carriages and can extend to more than two carriages in other examples of multiple carriage embodiments. The winding apparatus 50 is configured to make the pressure vessel 100 with interwoven filaments. The interwoven filaments are formed by winding the filaments simultaneously using multiple carriages that can be controlled independently. The winding apparatus 50 includes a spindle 54 on which a structural shell 104 can be made. The structural shell 104 can include a substantially cylindrical form or liner 108. The liner 108 can be formed of a polymer having a lightweight structure and is sometimes referred to herein as a lightweight liner. For other applications, other cylindrical forms can be used on the winding apparatus 50. The spindle 54 includes a rotating chuck or similar device that can support the liner 108 as it rotates about its longitudinal axis. Rotation of the spindle 54 may be provided by a motor 58 mechanically coupled to the spindle 54 .

[0022] The winding of the filament around the liner 108 may be performed by a carriage of the winding device 50. The winding device 50 may include a first carriage 62 having a first eye 66 and a second carriage 70 having a second eye 74. The first carriage 62 may be disposed on one side of the spindle 54. The first carriage 62 may be moved along a side of the space in which the spindle 54 supports the liner 108. The movement of the first carriage 62 allows the filament to be applied to the liner 108 in a first pattern. For example, the first carriage 62 may be configured to pay out a filament 112 from the first eye 66 that is well suited to provide a primary radial support to the liner 108. The first eye 66 may pay out a first filament 112A having a first material composition or a first configuration. The first filament 112A may be a hoop filament.

[0023] The second carriage 70 may be configured to move along a space spaced apart from the first carriage 62 and in which the liner 108 may be supported. The second carriage 70 may be disposed on the opposite side of the liner 108 from the first carriage 62 when the liner 108 is attached to the spindle 54. The second carriage 70 may be configured to move independently of the first carriage 62. The second carriage 70 may orient the second eye 74 to pay out the second filament 112B. The second filament 112B may have a second material composition that is different from the first material composition in some applications. The second filament 112B may have a configuration that makes the second filament 112B well suited for use as a helical filament. In some applications, the second filament 112B includes the same material as the first filament 112A. In some applications, the second filament 112B includes the same material or materials as the first filament 112A. If formed of the same material or materials as the first filament 112A, the second filament 112B can be of the same composition or a different composition. For example, the first filament 112A can have a high strength construction (e.g., a high strength carbon fiber material construction having a strength of about 700 ksi or more, about 800 ksi or more, about 900 ksi or more, about 1000 ksi or more, about 1100 ksi or more, about 1200 ksi or more, about 1300 ksi or more, or any range within the range defined by any combination of the foregoing numbers as endpoints) and the second filament 112B can be of a lower or lower strength construction (e.g., a low or lower strength carbon fiber material construction having a strength of about 300 ksi or more, about 400 ksi or more, about 500 ksi or more, about 600 ksi or more, or about 650 ksi or more, or any range within the range defined by any combination of the foregoing numbers as endpoints, or a glass fiber material having a strength of about 300 ksi). More generally, materials other than carbon fiber suitable for fiber wrapping as described herein that have strength properties within the ranges discussed above for high strength constructions other than carbon fiber may also be used for the first filament 112A.Materials other than carbon and glass fibers suitable for fiber wrapping as described herein that have strength properties within the aforementioned ranges for lower or less strength configurations may also be used for the first filament 112A.

[0024] FIG. 2 shows further details of the winding apparatus 50 and the process for manufacturing the structural shell 104. The liner 108 is shown in a side view. As mentioned above, the liner 108 is supported by the spindle 54 for rotation about its longitudinal axis LA. The winding apparatus 50 is controlled to move the first eye 66 and the second eye 74 to various positions along the liner 108. Two such positions are seen in FIG. 2. Specifically, winding position W1 is seen in solid lines, where the first eye 66 is controlled to pay out the first filament 112A in a primary hoop direction 116. The primary hoop direction 116 is a direction in which the longitudinal axis of the first filament 112A is oriented close to perpendicular to the meridian of the liner 108. The primary hoop direction 116 at winding position W1 may correspond to a hoop angle 137 between 60 and 90 degrees from a meridian of the liner 108 (e.g., a line parallel to the longitudinal axis LA). In some cases, the primary hoop direction 116 corresponds to a hoop angle 137 between 70 and 90 degrees from a meridian of the liner 108. In some cases, the primary hoop direction 116 corresponds to a hoop angle 137 between 80 and 90 degrees from a meridian of the liner 108.

[0025] In some instances, the primary helical direction 120 corresponds to a helical angle 138 of between about -20 degrees and about 0 degrees of the meridian of the liner 108, where the negative angle is measured in a clockwise direction as the angle between a first line extending from an origin on the left side of the longitudinal axis toward the right side and a second line, such as the primary helical direction 120. The primary helical direction 120 may correspond to a helical angle 138 of between about -10 degrees and about 0 degrees of the meridian of the liner 108. The primary helical direction 120 corresponds to a hoop angle 137 of between about -5 degrees and about 0 degrees of the meridian of the liner 108.

[0026] FIG. 2 shows three strands of the first filament 112A oriented toward the right at a hoop angle 137. Although these three strands appear to be separate strands, they are generally segments of a continuous first filament 112A that extends around the liner 108, with each segment spaced a short distance from adjacent segments as shown. The distance between adjacent segments of the first filament 112A depends on several factors, including the rotational speed of the spindle 54 (and liner 108), the speed of movement of the first carriage 62, and the thickness of the first filament 112A. Similarly, the second filament 112B appears to be three separate strands oriented with the right end angled downward relative to the left end and below the location of the longitudinal axis LA. These strands are generally adjacent segments of a continuous second filament 112B that is wound around the liner 108. The spacing between adjacent segments of the second filament 112B will be a function of the rotational speed of the liner 108, the movement speed of the second carriage 70, the orientation of the second eye 74, and the thickness of the second filament 112B.

[0027] The second filament 112B is wound on the liner 108 simultaneously with the first filament 112A to form the interwoven structure discussed herein. The first carriage 62 and the first eye 66 have a predetermined orientation relative to the liner 108 at the winding position W1. The second carriage 70 and the second eye 74 also have a predetermined orientation relative to the liner 108 at the position W1. In other words, the winding position W1 defines the orientation of both the first eye 66 and the second eye 74 at the particular winding instant seen in FIG. 2. The winding position W1 may define the orientation of the first eye 66 that creates the primary hoop direction 116 and the orientation of the second eye 74 that creates the primary helical direction 120. In some cases, other winding positions that provide a negative helical angle 138 and a hoop angle 137 less than 90 degrees may be provided along the center length of the liner 108. These angles may vary randomly within each pass. These angles may vary in a predetermined manner within each pass. These angles may vary in a predetermined manner from the first pass to subsequent passes.

[0028] FIG. 2 illustrates a winding position W4 corresponding to another winding condition or configuration of the winding apparatus 50. At the winding position W4, the first carriage 62 and the second carriage 70 are moved such that the first filament 112A and the second filament 112B are unwound at an angle different from that of the winding position W1. The first carriage 62 is moved along the longitudinal axis of the liner 108 to a position spaced apart from the position of the first carriage 62 at the winding position W1. The first eye 66 is oriented at a hoop angle 167. The hoop angle 167 can be between about 90 degrees and about 120 degrees from the meridian of the liner 108. In some cases, the primary hoop direction 116 corresponds to a hoop angle 167 between about 110 degrees and about 90 degrees from the meridian of the liner 108. In some cases, the primary hoop direction 116 corresponds to a hoop angle 167 between about 100 degrees and about 90 degrees from the meridian of the liner 108 .

[0029] The winding position W4, in some instances, provides that the primary helical direction 120 corresponds to a helical angle 168 between about 0 degrees and about 20 degrees from the meridian of the liner 108. The primary helical direction 120 may correspond to a helical angle 168 between about 0 degrees and about 10 degrees from the meridian of the liner 108. The primary helical direction 120 may correspond to a position between about 0 degrees and about 5 degrees from the meridian of the liner 108. The winding position W4 may change during operation of the winding apparatus 50. For example, a portion of the turns of the liner 108 may have a first combination of a hoop angle 167 greater than 90 degrees and a helical angle 168 greater than 0 degrees, and a second portion of the turns of the liner 108 may have another combination of a hoop angle 167 greater than 90 degrees and a helical angle 168 greater than 0 degrees.

[0030] Other winding positions between winding position W1 and winding position W4 are possible, as discussed further below. In some cases, the first carriage 62 and the second carriage 70 move several times along the length of the liner 108 to provide complete coverage of the liner 108, as discussed further below. As the first carriage 62 and the second carriage 70 move, the winding position W1 and the winding position W4 may change such that the angles of the first filament 112A and the second filament 112B relative to a meridian or relative to each other change over the length of the structural shell 104.

[0031] FIG. 2 shows that the winding process results in a woven or interwoven structure of the first filament 112A and the second filament 112B. The process allows the continuous strands of filament 112 and second filament 112B to achieve complete coverage of the liner 108 without requiring cutting of the first filament 112A to allow the filament 112 to be reoriented in the primary helical direction. The location of the first filament 112A may be limited to portions of the liner 108 that require more radial reinforcement. Also, the second filament 112B may be configured for the purpose of supporting the liner 108 against axial loads. The second filament 112B does not need to be reoriented in the primary hoop direction, as such reorientation would require an inefficient use of material and would limit the possible movement of the second carriage 70 and the second eye 74.

[0032] FIG. 2 shows that as the first carriage 62 and the second carriage 70 advance at the winding position W1, a single turn of the second filament 112B passes above and below adjacent strands of the first filament 112A. Specifically, it can be seen that the central segment of the second filament 112B passes above the left two segments of the first filament 112A and below the rightmost segment of the first filament 112A shown, thereby providing an interwoven or woven structure of the second filament 112B and the first filament 112A. The same is true for the first filament 112A. It can be seen that the central segment of the first filament 112A passes below the top two segments of the second filament 112B while passing above the bottommost segment of the second filament 112B, thereby providing an interwoven or woven structure of the first filament 112A and the second filament 112B. These overlying arrangements of the first filaments 112A and the second filaments 112B provide uniformity of material properties, particularly stiffness, across the surface of the layer 128 in the radial direction when the three-dimensional interwoven structure is formed, as discussed further below.

[0033] The winding position W1 creates a first braid angle α. The first braid angle α can be about 90 degrees, about 95 degrees, about 100 degrees, about 105 degrees, about 110 degrees, or within a range defined by any two of the aforementioned end points between the first filament 112A in the primary hoop direction 116 and the side-by-side woven second filament 112B in the primary helical direction 120. The winding position W4 creates a fourth braid angle θ between the primary helical direction 120 and the primary hoop direction 116. The fourth braid angle θ can be about 90 degrees, about 95 degrees, about 100 degrees, about 105 degrees, about 110 degrees, or within a range defined by any two of the aforementioned end points between the first filament 112A in the primary hoop direction 116 and the side-by-side woven second filament 112B in the primary helical direction 120. In one embodiment, the fourth braid angle θ at winding location W4 is the same as the first braid angle α at winding location W1.

[0034] 3A-3D show four portions of a weave structure 124 in which a first filament 112A and a second filament 112B are interwoven into a layer 128 on a liner 108. FIG. 3A shows a portion of a weave structure 124 in which a first interwoven hoop strand 134 of the first filament 112A is oriented at a hoop angle 137 and a first interwoven helical strand 136 of the second filament 112B is oriented at a helical angle 138. The hoop angle 137 includes angles less than 90 degrees from the meridian of the liner 108. The helical angle 138 includes negative angles, such as about -20 degrees, measured in a counterclockwise direction from the meridian of the liner 108. Other values ​​of the hoop angle 137 and the helical angle 138 are described above. In one embodiment, a first braid angle α is defined between adjacent braided segments of the continuous filaments 112A, 112B. The first braid angle α is, in one embodiment, approximately 100 degrees, with, for example, a hoop angle 137 of approximately 80 degrees and a helical angle 138 of approximately negative 20 degrees. Other values ​​for the first braid angle α are described above. The previously described weave structure 124 forms a first interweave 132 between adjacent braided strands.

[0035] FIG. 3B shows another portion of the woven structure 124 in which the second interwoven hoop strands 144 of the first filament 112A are oriented at a hoop angle 147 and the second interwoven helical strands 146 of the second filament 112B are oriented at a helical angle 148. The hoop angle 147 may include an angle greater than 90 degrees from the meridian of the liner 108, such as about 95 degrees, about 100 degrees, about 105 degrees, about 110 degrees, about 115 degrees, about 120 degrees, or an angle within a range including any of the foregoing as an end point. The helical angle 148 includes a negative angle measured in a counterclockwise direction from the meridian of the liner 108. The helical angle 148 may be the same as any of the examples of the helical angle 138. In one embodiment, a second braid angle β is defined between adjacent braided segments of the continuous filaments 112A, 112B. The second braid angle β, in one embodiment, is about 130 degrees, for example, with the hoop angle 147 being about 110 degrees and the helical angle 148 being about negative 20 degrees. Other second braid angles β are possible with combinations of the above exemplary values ​​for the hoop angle 147 and the helical angle 148. The above-described weave structure 124 forms second interlaces 142 between adjacent braided strands.

[0036] FIG. 3C shows another portion of the woven structure 124 where the third interwoven hoop strand 154 of the first filament 112A is oriented at a hoop angle 157 and the third interwoven helical strand 156 of the second filament 112B is oriented at a helical angle 158. The hoop angle 157 comprises an angle less than 90 degrees from the meridian of the liner 108. The hoop angle 157 may be any of the angles described above in connection with the hoop angle 137. The helical angle 158 may comprise a positive angle. In one embodiment, a third braid angle δ is defined between adjacent braided segments of the continuous filaments 112A, 112B. The third braid angle δ may be about 60 degrees in one embodiment, for example, with the hoop angle 157 being about 80 degrees and the helical angle 158 being about 20 degrees. Helical angle 158 can be the absolute value of any of the angles described above in connection with helical angle 138. Third braid angle δ can be any combination of the angles disclosed in connection with hoop angle 157 and helical angle 158. The weave structure 124 described above forms a third interlace 152 between adjacent braided strands.

[0037] 3D shows another portion of the woven structure 124 where the fourth interwoven hoop strand 164 of the first filament 112A is oriented at a hoop angle 167 and the fourth interwoven helical strand 166 of the second filament 112B is oriented at a helical angle 168. The hoop angle 167 comprises an angle greater than 90 degrees from the meridian of the liner 108. The hoop angle 167 can be a value corresponding to any of the values ​​disclosed in connection with the hoop angle 147. The helical angle 168 comprises a positive angle, e.g., any of the values ​​disclosed in connection with the helical angle 158. In one embodiment, a fourth braid angle θ is defined between adjacent braided segments of the continuous filaments 112A, 112B. The fourth braid angle θ can be about 90 degrees in one embodiment, e.g., with the hoop angle 167 being about 110 degrees and the helical angle 168 being about 20 degrees. Other values ​​for the fourth braid angle θ may be determined by combinations of the values ​​disclosed in connection with the hoop angle 167 and the helical angle 168. The previously described weave structure 124 forms a fourth interlace 162 between adjacent braided strands.

[0038] The first interlace 132, the second interlace 142, the third interlace 152, and the fourth interlace 162 may each result from a separate winding location. For example, the first interlace 132 corresponds to the winding location W1, and the fourth interlace 162 corresponds to the winding location W4. Although four separate winding locations can produce the four interlaces shown in FIGS. 3A-3D, the winding method may include more than four winding locations. The winding angles of the first filament 112A and the second filament 112B may each vary from a maximum winding angle for the primary hoop direction 116 to a minimum winding angle for the primary helical direction 120. In some cases, multiple turns may be provided at one winding location, followed by one or more turns at a different winding location to adjust the angle of approach to a boundary condition of the pressure vessel 100, such as an edge, an inflection point, or a physical feature of the structure.

[0039] FIG. 4 shows a schematic cross-section of the wall of the pressure vessel 100. In one embodiment, the innermost cavity of the pressure vessel 100 is surrounded by the inner wall of the liner 108. The liner 108 can be a lightweight polymeric liner, as described above. The outer surface of the liner 108 can be surrounded by a layer 128 comprising a three-dimensional interwoven structure. The layer 128 is formed by 2 to 30 passes of the first carriage 62 and the second carriage 70 of the winding device 50 along the liner 108 as the liner 108 is rotated by the spindle 54, and in some cases by 6 to 20 passes, such as 15 passes. Each pass can apply 1 to 10 loops of the first filament 112A in the primary hoop direction 116, and in some cases by 2 to 8 loops, such as 4, 5, 6, or 7 loops. Each pass can apply 1 to 10 loops of the second filament 112B in the primary helical direction 120, and in some cases 2 to 8 loops, such as 4, 5, 6, or 7 loops. In each pass, and with each revolution of the liner 108, the second filament 112B is woven with the first filament 112A, for example, by passing each arcuate segment of the first filament 112A over and under one or more (e.g., multiple) consecutive segments of the second filament 112B and / or by passing each arcuate segment of the second filament 112B over and under one or more (e.g., multiple) consecutive segments of the second filament 112B. The result is a continuous layer 128 of braided reinforcement. Ply 128 is a three-dimensional woven structure because with each pass of first carriage 62 and second carriage 70, first eye 66 and second eye 74 build additional weave thickness to the initial thickness applied to the exterior surface of liner 108. The stiffness of structural shell 104 is radially uniform across ply 128 due to first filaments 112A and second filaments 112B being present in equal proportions at various radial locations of ply 128.

[0040] The continuous nature of the layer 128 is illustrated by FIG. 4, which shows a solid line at the inner boundary at the innermost portion 128A of the layer 128 and a solid line at the outer boundary at the outermost portion 128B of the layer 128, without a separate boundary layer between the innermost and outermost portions. The dashed lines in FIG. 4 indicate that the total thickness of the layer 128 may be the result of multiple passes of the first carriage 62 and the second carriage 70 over the liner 108. However, the winding process results in a large amount of continuous material with no boundaries in stiffness properties between those winding passes. The winding process disclosed herein also avoids a separate boundary between a region where the filaments are primarily oriented only in the hoop direction without any filaments in the primary helical direction and an adjacent region where the filaments are primarily oriented only in the primary helical direction without any filaments in the primary hoop direction. The dashed lines suggest that the layer 128 may be made in four passes of the first carriage 62 and the second carriage 70, although the number of passes may be any number, including 15 or more passes, to completely encase the liner 108 within the support filament.

[0041] One exemplary application of what has been described thus far is in the production of hydrogen gas cylinders that can be used in fuel cell vehicles and other applications that use hydrogen gas. In this application, the pressure vessel 100 is configured to maintain a pressure of 700 bar without failure during operation. The first filament 112A includes a high strength carbon fiber material wound in a primary hoop direction as described above. The second filament 112B also includes a carbon fiber material wound in a primary helical direction as described above. In one embodiment, the first filament 112A and the second filament 112B include fibers having the same reinforcing performance, e.g., are formed with the same material composition, and may be the same fiber. The first filament 112A and the second filament 112B both contribute to radial load support, while the second filament 112B contributes more to axial load support. In some cases, the second filament 112B may be a lower performance (e.g., lower strength) configuration of carbon fiber. By interweaving the fibers, production of hydrogen gas cylinders can be completed quickly, at least in part, by reducing or eliminating the need to transition the fibers between hoop and helical orientations by cutting the fibers or changing the winding angle from a hoop angle to a helical angle. The interwoven structure provides uniform stiffness even when the material properties of the filaments 112A, 112B are different.

[0042] Another exemplary application of what has been described thus far is in making lower cost, and in some cases more durable, gas cylinders for CNG storage. In this approach, the first filament 112A may be made of a high strength material. The second filament 112B may be made of a lower strength material (same or different). The first filament 112A may include high strength carbon fiber. The second filament 112B may include a lower strength material, such as fiberglass. The lower strength of fiberglass requires more material to be wound than is structurally required. Specifically, fiberglass is thicker than carbon fiber. The additional material carries a weight penalty. However, fiberglass is less costly than carbon fiber, so the overall cost may be lower. Fiberglass is also more durable and has a higher fire resistance. Furthermore, fiberglass is also less susceptible to surface damage, such as abrasion from cutting and handling, due to its thickness. The less stiff glass is also less prone to disintegration if damaged. The thicker end portions are also more resistant to drop impact damage, which may allow the carbon-glass version of pressure vessel 100 to be shipped without the additional foam "bumpers" that are held on by adhesive and added to protect the cylinder.

[0043] Another exemplary application of what has been described is in the creation of a pipe assembly. In this assembly, a mold such as a pipe liner may be prepared. The pipe liner may be similar to the liner 108. The pipe assembly may not be closed at the end of the liner, unlike the pressure vessel 100. This maintains the function of the pipe assembly to carry gases and other fluids. The pipe assembly may incorporate a first filament 112A that may be composed of a high strength material. The second filament 112B may be composed of the same material or a lower strength (same or different) material. The first filament 112A may include a high strength carbon fiber. The second filament 112B may also include a high strength carbon fiber or may include a lower strength material, such as a lower strength carbon fiber or glass fiber. Interweaving the first filament 112A and the second filament 112B in the pipe assembly may provide a high burst pressure performance. Interweaving the first filament 112A and the second filament 112B in a pipe assembly can provide high speed throughput compared to other winding techniques.

[0044] The embodiments disclosed herein provide one or more of the following advantages: Significant cost savings can be realized by using lower cost fibers for fibers wound in one direction, such as the second filament 112B wound in the primary helical direction 120. As mentioned above, the second filament 112B can include fiberglass and / or lower strength carbon fiber, as two examples of materials that can be used for the second filament. These fibers can be significantly lower cost than the first filament 112A wound in the primary hoop direction 116, which in some cases has a higher strength configuration. As mentioned above, some fibers (e.g., fiberglass) used for the second filament 112B can be thicker, thus resulting in thicker end sections of the pressure vessel 100. The thicker end sections can allow for the elimination of strategies to improve drop test performance and / or other durability metrics. This can reduce or eliminate the cost, weight, and manufacturing process associated with providing bumpers or other durability reinforcements. Furthermore, the glass fibers provide the added benefit of being non-conductive, thus providing galvanic isolation to the metallic bosses. Metallic bosses are incorporated into the pressure vessel 100 in some embodiments, for example, for connection to piping outside the pressure vessel 100 and / or for mechanical support of the pressure vessel 100. Fibers that are subjected to lower pressure, such as glass fibers, are less likely to fracture in the event of a pressure vessel 100 rupture. Thus, providing such fibers throughout the thickness in a portion of the pressure vessel 100, such as the exterior surface of the domed end of the pressure vessel 100, enhances containment of the material in the event of a rupture.

[0045] As discussed above, winding the fiber in the primary hoop direction 116 and the primary helical direction 120 simultaneously can eliminate the need for transitions between these directions when a single eye / single carriage is provided. These and other benefits of simultaneous winding can allow the winding apparatus 50 to increase throughput, reduce the number of turns, and / or increase production capacity, as compared to winding the hoop layer and the helical layer sequentially or as entirely separate layers. In some cases, the layer 128 can provide a three-dimensional interwoven structure. The outer surface of the layer 128 can be on the outer surface of the pressure vessel 100. In some embodiments, a full wind of the first filament 112A can be provided to provide a custom appearance along with the other benefits of the pressure vessel 100 discussed above. In addition to providing a custom appearance, this additional finishing layer can allow other production systems to be used, such as automated squeegees, sanding, and other additional gas cylinder processing, instead of tank winding approaches that rely more on transitions.

[0046] Although specific embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the present disclosure. In fact, the novel methods and systems described herein may be embodied in various forms. Furthermore, various omissions, substitutions, and modifications in the systems and methods described herein may be made without departing from the spirit of the present disclosure. The appended claims and their equivalents are intended to cover such forms or modifications as fall within the scope and spirit of the present disclosure. Thus, the scope of the present invention is defined solely by reference to the appended claims.

[0047] Features, materials, properties, or groups described in connection with a particular aspect, embodiment, or example should be understood to be applicable to any other aspect, embodiment, or example described in this section or elsewhere in this specification, unless they are inconsistent. All of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except where at least some of such features and / or steps are mutually exclusive. Protection is not limited to the details of any of the foregoing embodiments. Protection extends to any novel feature or any novel combination of features disclosed in this specification (including any accompanying claims, abstract, and drawings), or any novel step or any novel combination of steps of any method or process so disclosed.

[0048] In addition, some features described in this disclosure in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a particular combination, in some cases, one or more features from the claimed combination may be deleted from the combination, and the combination may be claimed as a subcombination or a variation of the subcombination.

[0049] Furthermore, although operations may be shown in the figures or described in the specification in a particular order, such operations need not be performed in the particular order shown or in sequential order to achieve desirable results, nor need all operations be performed. Other operations not shown or described may be incorporated into the exemplary methods and processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the described operations. Furthermore, operations may be rearranged or reordered in other implementations. Those skilled in the art will appreciate that in some embodiments, the actual steps incorporated in the illustrated and / or disclosed processes may differ from those shown in the figures. Depending on the embodiment, some of the above steps may be removed or other steps may be added. Furthermore, the features and characteristics of the specific embodiments disclosed above may be combined in various ways to form further embodiments, all of which are within the scope of the present disclosure. It should also be understood that the distinctions between various system components in the above embodiments should not be understood as requiring such distinctions in all embodiments, and that the described components and systems may generally be incorporated together in a single product or packaged into multiple products.

[0050] For purposes of this disclosure, certain aspects, advantages, and novel features are described herein. Not all such advantages may be obtained in accordance with any particular embodiment. Thus, for example, one skilled in the art will recognize that the present disclosure may be embodied or performed in a manner that obtains one or a group of advantages taught herein, without necessarily obtaining other advantages that may be taught or suggested herein.

[0051] Conditional language such as "can," "could," "might," or "may" is generally intended to convey that certain embodiments include certain features, elements, and / or steps while other embodiments do not, unless specifically stated otherwise or understood otherwise within the context in which it is used. Thus, such conditional language is generally not intended to imply that features, elements, and / or steps are required in any way in one or more embodiments, or that one or more embodiments necessarily include logic for determining, with or without user input or action, whether those features, elements, and / or steps are included in or should be performed in any particular embodiment.

[0052] Conjunctive language such as the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is understood in the context in which it is generally used to convey that an item, term, etc. can be either X, Y, or Z. Thus, such conjunctive language is generally not intended to imply that a particular embodiment requires the presence of at least one X, at least one Y, and at least one Z.

[0053] As used herein, degree-related terms such as the terms "approximately," "about," "generally," and "substantially" refer to values, amounts, or characteristics that are close to the stated value, amount, or characteristic that still performs a desired function or obtains a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to amounts that are within 10%, 5%, 1%, 0.1%, and 0.01% of the stated amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to values, amounts, or characteristics that deviate from strictly parallel by 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degrees or less.

[0054] The scope of the present disclosure is not intended to be limited by the specific disclosure of preferred embodiments in this section or elsewhere herein, but may be defined by the claims as they are presented in this section or elsewhere herein or as they may be presented in the future. The language set forth in the claims should be interpreted broadly based on the language used in the claims, and not limited to the examples described herein or during prosecution of the application, such examples being interpreted as being comprehensive. [Explanation of symbols]

[0055] 50 Winding device 54 Spindle 58 Motor 62 First Carriage 66 First Eye 70 Second Carriage 74 Second Eye 100 Pressure vessels 104 Structural Shell 108 Raina 112 Filament 112A First Filament 112B Second filament 116 Primary Hoop Direction 120 Primary Helical Direction 124 Woven structure 128 layers 128A Innermost part 128B Outermost part 132 First Interweaving 134 First interwoven hoop strand 136 First interwoven helical strand 137 Hoop Angle 138 Helical Angle 142 The Second Interweaving 144 Second interwoven hoop strand 146 Second interwoven helical strand 147 Hoop Angle 148 Helical Angle 152 The Third Interweaving 154 3rd interwoven hoop strand 156 Third interwoven helical strand 157 Hoop Angle 158 Helical Angle 162 The Fourth Interweaving 164 Fourth Interwoven Hoop Strand 166 Fourth interwoven helical strand 167 Hoop Angle 168 Helical Angle LA Longitudinal Axis W1 winding position W4 winding position α First braid angle β Second braid angle δ Third braid angle θ 4th braid angle

Claims

1. A liner having a cylindrical central portion and two dome-shaped portions; a structural shell disposed directly about the liner, the structural shell comprising: a first filament wound in a primary hoop direction around the liner; a second filament wound in a primary helical direction around the liner; a structural shell comprising: A pressure vessel comprising: the first filaments and the second filaments are interwoven into a layer such that the first filaments and the second filaments are laid down on the liner simultaneously.

2. The pressure vessel of claim 1 , wherein the first filament is made from carbon fiber.

3. The pressure vessel of claim 1 , wherein the second filament is made from fiberglass.

4. A pressure vessel as described in claim 1, wherein the first filament has a material composition that includes carbon and provides higher strength, and the second filament has a material composition that includes carbon and provides lower strength.

5. 2. The pressure vessel of claim 1, wherein the layer has a continuous extent from the outer surface of the liner to the outer surface of the pressure vessel with no layer boundary between the outer surface of the liner and the outer surface of the pressure vessel.

6. The pressure vessel of claim 1 , wherein the layer comprises a three-dimensional woven structure.

7. 7. The pressure vessel of claim 6, wherein the layer comprises first hoop filaments and first helical filaments that cross over each other at a first angle in a first portion of the three-dimensional interwoven structure, and the first hoop filaments and the first helical filaments cross over each other at a second angle in a second portion of the three-dimensional interwoven structure.

8. 8. The pressure vessel of claim 7, wherein the first angle is approximately 90 degrees and the second angle is approximately 110 degrees.

9. Attaching a liner to a spindle; rotating the liner using the spindle; winding a first filament in a primary hoop direction while rotating the liner; while winding the first filament, simultaneously winding a second filament in a primary helical direction; A method comprising: The method wherein the simultaneous winding of the first filament and the second filament provides an interwoven structure disposed about the liner reinforcing the liner.

10. The method of claim 9 , wherein the first filament has a higher strength than the second filament.

11. The method of claim 10 , wherein the first filament has a stronger carbon construction and the second filament has a weaker carbon construction.

12. The method of claim 10 , wherein winding the first filament comprises winding a carbon fiber.

13. The method of claim 12 , wherein winding the second filament comprises winding a glass fiber.

14. 10. The method of claim 9, wherein the steps of winding the first filament and simultaneously winding the second filament are performed with at least one of the first filament and the second filament being continuous from an inner boundary of a complete reinforced structure to an outer boundary of the complete reinforced structure.

15. 10. The method of claim 9, wherein winding the first filament comprises adjusting a first eye of a winding device through a first angular range relative to a meridian of the liner, and simultaneously winding the second filament comprises adjusting a second eye of the winding device through a second angular range relative to the meridian of the liner, the first angular range not overlapping with the second angular range.

16. The method of claim 15 , wherein the first range of angles corresponds to a primary hoop direction and the second range of angles corresponds to a primary helical direction.

17. The method of claim 15 , wherein the first range of angles is between about 80 degrees and about 100 degrees.

18. The method of claim 15, wherein the second range of angles is between about 20 degrees and about -20 degrees.

19. a substantially cylindrical liner; a first filament wound in a primary hoop direction around the liner; a second filament wound in a primary helical direction around the liner; A pressure vessel comprising: the first filaments and the second filaments are woven onto the liner such that first portions of the first filaments are disposed above the second filaments and second portions of the first filaments are disposed below the second filaments.

20. 20. The pressure vessel of claim 19, wherein the first filaments comprise a first material and the second filaments comprise a second material different from the first material.

21. 21. The pressure vessel of claim 20, wherein the first material comprises carbon fiber.

22. 21. The pressure vessel of claim 20, wherein the second material comprises fiberglass.

23. 20. The pressure vessel of claim 19, wherein the first filaments and the second filaments are wound in a three-dimensional interwoven layer having a continuous extent from the outer surface of the liner to the outer surface of the pressure vessel without a layer boundary between the outer surface of the liner and the outer surface of the pressure vessel.

24. 24. The pressure vessel of claim 23, wherein the three-dimensional interwoven layer comprises a first hoop filament and a first helical filament that cross over each other at a first angle in a first portion of the three-dimensional interwoven layer, and the first hoop filament and the first helical filament cross over each other at a second angle in a second portion of the three-dimensional interwoven layer.

25. 25. The pressure vessel of claim 24, wherein the first angle is approximately 90 degrees and the second angle is approximately 110 degrees.

Images