Molding system and method for forming a structure

Abstract

A molding system and method for molding a structure are provided. The molding system is configured to mold a composite structure. The molding system includes: a first tool including a first vacuum groove, a first groove, and a first molding surface, the first groove having a first edge configured to mold a first curved portion of the composite structure; and a second tool including a second vacuum groove, a second groove, and a second molding surface, the second groove having a second edge configured to mold a second curved portion of the composite structure.

Description

Technical Field

[0001] The present disclosure relates generally to forming structures, and more particularly to using a molding system to shape preforms. Background Art

[0002] Some composite structures, such as composite reinforcing bars, have complex bends along their length. In addition, some composite structures, such as composite reinforcing bars, have non-planar cross-sections. Composite reinforcing bars may have a C-shaped, T-shaped, hat-shaped, or other desired cross-sections.

[0003] Traditionally, Z-sections are formed by one of hand layup, layer by layer, or by stamping using matching male and female tools. Hand layup, layer by layer, involves sweeping each layer into each radius. Hand layup, layer by layer, is undesirably labor intensive, involves considerable skill, and is ergonomically undesirable. Thus, hand layup, layer by layer, has at least one of an undesirably long time or an undesirably high manufacturing cost.

[0004] When stamping large or complex parts, material volume factors and manufacturing tolerances can cause inconsistencies. Stamping is performed on an initial, substantially flat layup using matching male and female tools. However, stamping is typically performed with relatively simple geometries. When stamping large or complex parts, material volume factors and manufacturing tolerances can cause inconsistencies.

[0005] It would therefore be desirable to have a method and apparatus that takes into account at least some of the issues discussed above as well as other possible issues. Summary of the invention

[0006] Embodiments of the present disclosure provide a molding system configured to shape a composite structure. The molding system includes: a first tool including a first vacuum groove, a first groove, and a first molding surface, wherein the first groove has a first edge configured to shape a first curved portion of the composite structure; and a second tool including a second vacuum groove, a second groove, and a second molding surface, wherein the second groove has a second edge configured to shape a second curved portion of the composite structure.

[0007] Another embodiment of the present disclosure provides a method of forming a structure by at least partially evacuating a first vacuum chamber between a first tool and a preform, pulling the preform over a first feature of the first tool, thereby forming a first curvature of the cross-section of the structure into the preform. By at least partially evacuating a second vacuum chamber between a second tool and the preform, pulling the preform over a second feature of the second tool located above the first tool, thereby simultaneously forming a second curvature of the cross-section of the structure into the preform.

[0008] Yet another embodiment of the present disclosure provides a method of molding a structure. A first bagging layer is sealed to a first tool. When a preform is between the first bagging layer and the second bagging layer, the second bagging layer is sealed to the first tool. The second tool is sealed to the second bagging layer. A first vacuum chamber formed by the first bagging layer and the first tool is at least partially evacuated while a second vacuum chamber formed by the second bagging layer and the second tool is at least partially evacuated to simultaneously mold the preform to a molding surface of the first tool and a molding surface of the second tool.

[0009] The features and functions can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments, more details of which can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The novel features believed characteristic of the illustrative embodiments are set forth in the appended claims. However, the illustrative embodiments and their preferred modes of use, further objects and features will be best understood by reference to the following detailed description of illustrative embodiments of the present disclosure when read in conjunction with the accompanying drawings, in which:

[0011] Figure 1 is an illustration of a block diagram of a manufacturing environment in which illustrative embodiments may be implemented;

[0012] Figure 2 is an illustration of a cross-sectional view of a composite structure according to an illustrative embodiment;

[0013] Figure 3 is an illustration of an isometric view of a molding system according to an illustrative embodiment;

[0014] Figure 4 is an illustration of a top view of a first tool of a molding system according to an illustrative embodiment;

[0015] Figure 5 is an illustration of a cross-sectional view of a first tool of a molding system according to an illustrative embodiment;

[0016] Figure 6 is an illustration of a top view of a second tool of a molding system according to an illustrative embodiment;

[0017] Figure 7 is an illustration of a cross-sectional view of a second tool of a molding system according to an illustrative embodiment;

[0018] Figure 8 is an illustration of a top view of a first tool of a molding system having a sealing material according to an illustrative embodiment;

[0019] Fig. 9is an illustration of a top view of a sealing material surrounding a groove and a first molding surface of a first tool of a molding system in accordance with an illustrative embodiment;

[0020] Fig.10 is an illustration of a top view of a first bagging layer sealed to a first tool of a molding system in accordance with an illustrative embodiment;

[0021] Fig.11 is an illustration of a top view of a preform placed over a first bagging layer and a first tool of a molding system in accordance with an illustrative embodiment;

[0022] Fig.12 is an illustration of a top view of a second bagging layer sealed over a first bagging layer and sealed to a first tool of a molding system in accordance with an illustrative embodiment;

[0023] Fig.13 is an illustration of a top view of material placed onto a second molding surface of a second tool of a molding system in accordance with an illustrative embodiment;

[0024] Fig.14 is an illustration of a top view of a sealing material placed around a second vacuum groove of a second tool of a molding system in accordance with an illustrative embodiment;

[0025] Fig.15 is an illustration of a top view of a molding system having a second tool sealed to a second bagging layer over a first tool in accordance with an illustrative embodiment;

[0026] Fig.16 is an illustration of a cross-sectional view of a preform between a first bagging layer and a second bagging layer, the first bagging layer and the second bagging layer both being sealed to a first tool of a molding system, and the second tool being sealed to the second bagging layer, in accordance with an illustrative embodiment;

[0027] Fig.17 is an illustration of a cross-sectional view of a preform formed to a first edge of a first slot of a first tool and a second edge of a second slot of a second tool in accordance with an illustrative embodiment;

[0028] Fig.18 is an illustration of a flow chart of a method of shaping a structure according to an illustrative embodiment;

[0029] Fig.19 is an illustration of a flow chart of a method of shaping a structure according to an illustrative embodiment;

[0030] Fig. 20 is an illustration of a block diagram of an aircraft manufacturing and service method according to an illustrative embodiment; and

[0031] Fig.21is an illustration of a block diagram of an aircraft in which an illustrative embodiment may be implemented. DETAILED DESCRIPTION

[0032] The illustrative embodiments recognize and take into account one or more different considerations. The illustrative embodiments recognize and take into account that ply-by-ply hand layup relies on each ply remaining in place after being formed into any concave bends. However, with a dry material system, the material will not remain in the concave bends. The illustrative embodiments recognize and take into account that ply-by-ply hand layup for prepreg systems may have varying success depending on the skill of the operator and the viscosity of the material.

[0033] The stamping between the male and female tools utilizes high forces and hard tooling to force the layup stack into the shape presented by the cavity between the mating tools. In this way, structural fibers may be damaged or broken when they are forced into contours into which they would not naturally drape. Damage is likely to occur if the fibers have been formed around and / or over a particular feature and are subsequently forced into another feature as the cavity size is reduced due to the tools closing together.

[0034] The illustrative embodiments recognize and take into account that vacuum forming can be used to pull the composite preform toward a male mold. The illustrative embodiments recognize and take into account that existing vacuum forming methods for composite stiffeners are limited to C-shaped sections due to inconsistencies with existing vacuum forming or hot crimping of more complex parts (e.g., bridging, corrugation, or radius thinning).

[0035] The illustrative embodiments recognize and take into account that dual diaphragm forming can be used to form a C-shaped cross section. Dual diaphragm forming utilizes a simplified initial flat (or single curved) charge layup. Dual diaphragm forming provides a forming technique that can better control or prevent inconsistencies and reduce manual operations that increase labor costs.

[0036] The illustrative embodiments recognize and take into account that this will result in the application of known diaphragm forming methods to the Z-shaped cross-section.

[0037] The illustrative examples provide molding systems and methods to achieve the advantages of diaphragm molding of more complex cross-sectional shapes. The illustrative examples provide the advantages of a dual diaphragm molding process of more complex configurations than previously possible.

[0038] Now turn to Figure 1 , which shows an illustration of a block diagram of a manufacturing environment in which illustrative embodiments may be implemented. Manufacturing environment 100 is an environment in which molding system 102 is used to mold features 104 of structure 106. In some illustrative examples, structure 106 takes the form of composite structure 107.

[0039] The molding system 102 is configured to mold a composite structure 107. The molding system 102 includes a first tool 108 and a second tool 110. The first tool 108 includes a first vacuum groove 112, a first groove 114, and a first molding surface 120, the first groove 114 having a first edge 116 configured to mold a first bend 118 of the composite structure 107. The second tool 110 includes a second vacuum groove 122, a second groove 124, and a second molding surface 130, the second groove 124 having a second edge 126 configured to mold a second bend 128 of the composite structure 107.

[0040] The first groove 114 and the first molding surface 120 are part of a molding surface 132 of the first tool 108. The second groove 124 and the second molding surface 130 are part of a molding surface 134 of the second tool 110.

[0041] First vacuum groove 112 is designed to secure the bagging layer so that the bagging layer does not slide into first groove 114. First vacuum groove 112 has any desired shape. In some illustrative examples, first vacuum groove 112 has a C-shape 136 that extends around a portion of first groove 114. With first vacuum groove 112 having C-shape 136, first vacuum groove 112 secures the bagging layer on three edges of first groove 114. In some illustrative examples, a sealing material is positioned in or around first vacuum groove 112 to seal the bagging layer to first vacuum groove 112.

[0042] Second vacuum groove 122 is designed to secure the bagging layer so that the bagging layer does not slide into second groove 124 during the molding of the preform. Second vacuum groove 122 has any desired shape. In some illustrative examples, second vacuum groove 122 has a C-shape 138 extending around a portion of second groove 124.

[0043] In some illustrative examples, first tool 108 has a larger footprint than second tool 110. In these illustrative examples, perimeter 140 of first tool 108 is larger than perimeter 142 of second tool 110.

[0044] Also present in the molding system 102 are a first bagging layer 144 and a second bagging layer 146. The first bagging layer 144 is sealed to the first tool 108 between the first vacuum groove 112 and the first slot 114 such that the first bagging layer 144 extends over the first slot 114.

[0045] The second bagging layer 146 is sealed to the first tool 108 such that the second bagging layer 146 extends over the first vacuum groove 112 and the first slot 114. Any desired sealing material is used to seal the first bagging layer 144 and the second bagging layer 146 to the first tool 108. The sealing material takes the form of an adhesive transfer tape, a mastic, a sealant, or any other desired type of sealing material.

[0046] Sealing first bagging layer 144 to first tool 108 forms first vacuum chamber 148, first cavity 150, and third vacuum chamber 152. First vacuum chamber 148 is formed between first slot 114 and first bagging layer 144. A sealing material (not shown) extends around first slot 114 to seal first bagging layer 144 to first tool 108. In some illustrative examples, two different types of sealing materials are used in combination to form first vacuum chamber 148.

[0047] A first cavity 150 is formed above the first molding surface 120. A sealing material (not shown) extends around the first molding surface 120 to seal the first bagging layer 144 to the first tool 108.

[0048] A third vacuum chamber 152 is formed over the remainder of the molding surface 132. A sealing material (not shown) extends around a portion of the molding surface 132 to seal the first bagging layer 144 to the first tool 108.

[0049] In some illustrative examples, the sealing material follows the perimeter of first bagging layer 144. In some illustrative examples, the sealing material following the perimeter of first bagging layer 144 forms portions of first vacuum chamber 148, first cavity 150, and third vacuum chamber 152.

[0050] Second bagging layer 146 is sealed to first tool 108. When second bagging layer 146 is sealed to first tool 108, first bagging layer 144 and second bagging layer 146 form a compacted region 154. A preform 156 to be formed into structure 106 is present in compacted region 154.

[0051] Preform 156 is a flexible material configured to be molded in a mold. In some illustrative examples, preform 156 takes the form of a composite material or a composite precursor. In some illustrative examples, preform 156 is a dry cloth 158. When preform 156 is a dry cloth 158, after molding, dry cloth 158 will be infused with resin. In some illustrative examples, preform 156 is a prepreg 160. In some illustrative examples, when preform 156 is a prepreg 160, prepreg 160 is heated before molding preform 156 onto molding surface 132 of first tool 108.

[0052] Second bagging layer 146 is sealed over preform 156 and first bagging layer 144. In some illustrative examples, the sealing material follows the perimeter of second bagging layer 146. In some illustrative examples, the sealing material following the perimeter of second bagging layer 146 forms compacted area 154.

[0053] The second bagging layer 146 has a larger footprint than the first bagging layer 144. The surface area 162 of the second bagging layer 146 is greater than the surface area 164 of the first bagging layer 144.

[0054] The second tool 110 is sealed to the second bagging layer 146 above the first molding surface 120 of the first tool 108. The second tool 110 is sealed to the second bagging layer 146 such that the second groove 124 faces the first molding surface 120.

[0055] When the second tool 110 is sealed to the second bagging layer 146 , the second bagging layer 146 and the second tool 110 form a second vacuum chamber 166 , a second cavity 168 , and a second vacuum recess space 170 .

[0056] In this illustrative example, first tool 108 and second tool 110 are configured to form structure 106 having Z-shaped 172 cross-section 174. Z-shaped 172 cross-section 174 includes first bend 118 formed by first tool 108 and second bend 128 formed by second tool 110. First bend 118 connects an arm of Z-shaped 172 cross-section 174 to a web of Z-shaped 172 cross-section 174. Second bend 128 connects a second arm of Z-shaped 172 cross-section 174 to the web of Z-shaped 172 cross-section 174.

[0057] The first tool 108 and the second tool 110 are configured to substantially simultaneously form the first bend 118 and the second bend 128. The preform 156 will be formed over the first edge 116 and the second edge 126 substantially simultaneously.

[0058] After sealing second tool 110 to second bagging layer 146, pressure is controlled in each of first vacuum chamber 148, first cavity 150, third vacuum chamber 152, compaction region 154, second cavity 168, second vacuum chamber 166, and second vacuum recess space 170. The pressure in each area of ​​molding system 102 is controlled to shape cross-section 174 of composite structure 107.

[0059] First, a vacuum is simultaneously drawn in the first cavity 150 formed by the first bagging layer sealed to the first tool 108 and the second cavity 168 formed by the second bagging layer 146 sealed to the second tool 110. The vacuum is provided through ports (not shown) of the first tool 108 and the second tool 110. The ports are provided at any desired locations of the first tool 108 and the second tool 110.

[0060] Simultaneously pulling a vacuum in the first cavity 150 and the second cavity 168 clamps the first bagging layer 144 to the first tool 108 and the second bagging layer 146 to the second tool 110. Simultaneously pulling a vacuum in the first cavity 150 and the second cavity 168 is performed before at least partially evacuating the first vacuum chamber 148 and the second vacuum chamber 166.

[0061] A vacuum is drawn in the first vacuum groove 112 of the first tool 108 to clamp the second bagging layer 146 to the first tool 108. Clamping the second bagging layer 146 to the first tool 108 constrains the second bagging layer 146 and the first bagging layer 144 from being pulled into the first groove 114 of the first tool 108.

[0062] In some illustrative examples, sealing material is associated with first vacuum groove 112. In these illustrative examples, drawing a vacuum in first vacuum groove 112 draws a vacuum in first vacuum groove space 169 formed by second bagging layer 146, first vacuum groove 112, and sealing material.

[0063] A vacuum is drawn in the second vacuum groove 122 of the second tool 110 to clamp the second bagging layer 146 to the second tool 110. Clamping the second bagging layer 146 to the second tool 110 limits the second bagging layer 146 from being pulled into the second groove 124 during forming of the preform 156. Drawing a vacuum in the second vacuum groove 122 draws a vacuum in the second vacuum groove space 170 formed by the second bagging layer 146, the second vacuum groove 122, and the sealing material.

[0064] After the vacuum is drawn in second vacuum groove 122, the cavity between first bagging layer 144 and second bagging layer 146 is at least partially evacuated to clamp first tool 108 and second tool 110 together and compact a portion of preform 156. In these illustrative examples, the cavity is compaction region 154. By at least partially evacuating compaction region 154, first tool 108 and second tool 110 are clamped together and a portion of preform 156 between first molding surface 120 and second molding surface 130 is compacted. Compacting preform 156 between first molding surface 120 and second molding surface 130 will form a "web" of Z-shaped 172 cross-section 174.

[0065] Preform 156 is simultaneously formed to molding surface 132 of first tool 108 and molding surface 134 of second tool 110 by at least partially evacuating first vacuum chamber 148 formed by first bagging layer 144 and first tool 108, while at least partially evacuating second vacuum chamber 166 formed by second bagging layer 146 and second tool 110. Preform 156 is pulled over first edge 116 to form first bend 118 by at least partially evacuating first vacuum chamber 148. Preform 156 is pulled over second edge 126 to form second bend 128 by at least partially evacuating second vacuum chamber 166. In some illustrative examples, after simultaneously molding preform 156 to molding surface 132 of first tool 108 and molding surface 134 of second tool 110, preform 156 is heated to set cross-section 174.

[0066] Figure 1 The illustration of manufacturing environment 100 in FIG. 1 is not meant to imply physical or architectural limitations on the manner in which the illustrative embodiments may be implemented. Other components in addition to or in place of the components shown may be used. Some components may be unnecessary. In addition, the display boxes are used to illustrate some functional components. When implemented in the illustrative embodiments, one or more of these boxes may be combined, divided, or combined and divided into different boxes.

[0067] For example, although sealing material is not shown, sealing material is present to seal the first bagging layer 144 to the first tool 108, the second bagging layer 146 to the first tool 108, and the second tool 110 to the second bagging layer 146. As another example, there are any desired types and numbers of treatment layers. In one illustrative example, there are several ventilation layers in the molding system 102. In one illustrative example, a ventilation layer is present between the first molding surface 120 and the first bagging layer 144. In another illustrative example, a ventilation layer is present between the first bagging layer 144 and the preform 156.

[0068] Now turn to Figure 2 , an illustration of a cross-sectional view of a composite structure is shown in accordance with an illustrative embodiment. Composite structure 200 is Figure 1 1. The composite structure 200 is a physical embodiment of the composite structure 107. The composite structure 200 may also be referred to as a stiffener or stringer. The composite structure 200 has a cross-section 202 with a Z-shape 204. The composite structure 200 has a first bend 206 and a second bend 208. The first bend 206 is positioned between the arm 210 and the web 212. The second bend 208 is positioned between the arm 214 and the web 212.

[0069] Although view 216 shows only cross section 202, additional three-dimensional shapes exist in composite structure 200. For example, composite structure 200 may also have bends, twists, or other three-dimensional complex shapes as composite structure 200 moves in and out of the page. The bends, twists, or other three-dimensional complex shapes are independent of cross section 202. The additional three-dimensional shapes as composite structure 200 moves in and out of the page are related to surrounding structures. For example, when composite structure 200 is to be bonded to a surrounding structure, the bend of the surrounding structure affects the bend of composite structure 200 so that composite structure 200 will follow the bend of the surrounding structure.

[0070] Now turn to Figure 3 , an illustration of an isometric view of a molding system is shown according to an illustrative embodiment. The molding system 300 is Figure 1 The molding system 300 can be used to shape the composite structure 200.

[0071] The molding system 300 is configured to mold a composite structure. The molding system 300 includes a first tool 302 and a second tool 304. The first tool 302 includes a first vacuum groove 306, a first groove 308, and a first molding surface (not visible), the first groove 308 having a first edge (not visible) configured to mold a first curved portion of the composite structure. The second tool 304 includes a second vacuum groove (not visible), a second groove 310, and a second molding surface (not visible), the second groove 310 having a second edge (not visible) configured to mold a second curved portion of the composite structure. As shown, the first vacuum groove 306 has a C-shape 312 extending around a portion of the first groove 308.

[0072] To shape the composite structure, the molding system 300 will also include vacuum forming materials, such as bagging layers, sealing materials, vent sheets, or other vacuum forming materials. During the shaping of the composite structure, the vacuum forming materials will be positioned between the first tool 302 and the second tool 304.

[0073] Now turn to Figure 4 , a diagram showing a top view of a first tool of a molding system is shown according to an illustrative embodiment. The first tool 400 is Figure 1 In some illustrative examples, first tool 400 is used to Figure 2 In some illustrative examples, first tool 400 may be used with Figure 3 The same as the first tool 302 .

[0074] First tool 400 includes first vacuum groove 402, first groove 404 having first edge 406 configured to mold a first bend of a composite structure, and first molding surface 408. Molding surface 410 includes first groove 404 and first molding surface 408 configured to mold a feature into a composite structure.

[0075] The first tool 400 has a plurality of ports 412 configured to connect to a vacuum source. The plurality of ports 412 includes port 414, port 416, port 418, port 420, and port 422.

[0076] Port 414 is present in the first groove 404. Port 414 is configured to evacuate a first vacuum chamber formed by the first groove 404 to mold the preform to the first edge 406. Port 416 is present in the first vacuum groove 402. Port 416 is configured to seal the vacuum bagging layer to the first tool 400. Port 416 constrains the vacuum bagging layer to limit the movement of the vacuum bagging layer into the first groove 404 during molding. Port 418 is present in the first molding surface 408. Port 418 is configured to evacuate a first cavity formed by the first molding surface 408 and the bagging layer. Port 418 provides a vacuum to clamp the bagging layer to the first tool 400 before molding the preform. Port 420 is present in the molding surface 410. Port 420 is configured to evacuate a third vacuum chamber. Port 422 is present in the first molding surface 408.

[0077] Now turn to Figure 5 , a diagrammatic representation of a cross-sectional view of a first tool of a molding system is shown according to an illustrative embodiment. View 500 is Figure 4 A cross-sectional view of the first tool 400. View 500 in Figure 4 Indicated above by number 5. In view 500 the first edge 406 can be seen more clearly.

[0078] Now turn to Figure 6 , an illustration of an isometric view of a second tool of a molding system is shown according to an illustrative embodiment. The second tool 600 is Figure 1 In some illustrative examples, second tool 600 is used to Figure 2 In some illustrative examples, second tool 600 may be used with Figure 3 The same as the second tool 304 .

[0079] The second tool 600 includes a second vacuum groove 602 , a second slot 604 having a second edge 606 configured to mold a second curved portion of the composite structure, and a second molding surface 608 .

[0080] Molding surface 610 includes second groove 604 and second molding surface 608 configured to mold a feature into a composite structure.

[0081] The second tool 600 has a plurality of ports 612 configured to connect to a vacuum source. The plurality of ports 612 includes port 614, port 616, and port 618.

[0082] Port 614 is present in second slot 604. Port 614 is configured to evacuate a second vacuum chamber formed by second slot 604 to mold the preform to second edge 606. Port 616 is present in second vacuum recess 602. Port 616 is configured to seal the second bagging layer to second tool 600. Port 618 is present in second molding surface 608. Port 618 is configured to seal the second bagging layer to second tool 600 at second molding surface 608.

[0083] Now turn to Figure 7 , an illustration of a cross-sectional view of a second tool of a molding system is shown according to an illustrative embodiment. View 700 is Figure 6 A cross-sectional view of the second tool 600. View 700 is Figure 6 Indicated above by number 7. In view 700 the second edge 606 can be seen more clearly.

[0084] Figure 8-17 A series of views are shown of a composite structure being formed using a molding system. For ease of illustration, some components are shown in FIG. Figure 8-17 Depicted as transparent. Figure 8-17 The depiction of components in does not limit the implementation of the illustrative examples. Figure 8 Initially, an illustration of a top view of a first tool of a molding system having a sealing material is shown in accordance with an illustrative embodiment.

[0085] First tool 800 includes first vacuum groove 802, first groove 804 having first edge 806 configured to mold a first curved portion of a composite structure, and first molding surface 808. Molding surface 810 includes first groove 804 and first molding surface 808 configured to mold a feature into a composite structure.

[0086] The first tool 800 is Figure 1 In some illustrative examples, first tool 800 is used to Figure 2 In some illustrative examples, the first tool 800 may be used with Figure 3In some illustrative examples, first tool 800 may be the same as first tool 302. Figure 4 The same as the first tool 400 .

[0087] In view 811, adhesive transfer tape 812 is present on either side of vent sheet 814. Adhesive transfer tape 812 is a sealing material. Vent sheet 814 is positioned over first molding surface 808 and ports 816 in first molding surface 808. Vent sheet 814 distributes vacuum from ports 816 over first molding surface 808 between adhesive transfer tape 812.

[0088] Now turn to Fig. 9 , an illustration of a top view of a sealing material surrounding a slot and a first molding surface of a first tool of a molding system is shown according to an illustrative embodiment. In view 900, sealing material 902 has been positioned on molding surface 810 surrounding first molding surface 808 and slot 804 such that sealing material 902 is in contact with adhesive transfer tape 812.

[0089] Now turn to Fig.10 , an illustration of a top view of a first bagging layer sealed to a first tool of a molding system is shown according to an illustrative embodiment. In view 1000, a first bagging layer 1002 has been placed over a first groove 804 and a first molding surface 808. The first bagging layer 1002 is sealed to the first tool 800 by a sealing material 902.

[0090] Sealing the first bagging layer 1002 to the first tool 800 forms a first vacuum chamber 1004, a first cavity 1006, and a third vacuum chamber 1008. Prior to forming the preform, the first cavity 1006 is at least partially evacuated to clamp the first bagging layer 1002 to the first molding surface 808. The first vacuum chamber 1004 will be at least partially evacuated to form the preform. The first vacuum chamber 1004 is at least partially evacuated by applying a vacuum using a port 1010 in the first slot 804. During the forming of the preform, the pressure in the third vacuum chamber 1008 is controlled to allow the forming of the preform. The pressure in the third vacuum chamber 1008 is controlled using a port 1012. In some illustrative examples, the third vacuum chamber 1008 is vented to the atmosphere.

[0091] In view 1000, layer 1014 is placed on first bagging layer 1002. A preform will be placed over layer 1014 in a subsequent step. Layer 1014 provides any desired handling characteristics. In some illustrative examples, layer 1014 is at least one of a vent sheet or a release film.

[0092] Now turn to Fig.11, an illustration of a top view of a preform placed over a first bagging layer and a first tool of a molding system is shown according to an illustrative embodiment. In view 1100, a vent sheet 1102 is placed over first bagging layer 1002, and a preform 1104 is placed over vent sheet 1102.

[0093] The vent sheet 1102 is positioned above the port 1106 of the first tool 800. The first port 1106 provides a vacuum to the compacted area containing the preform 1104. The vacuum provided to the first port 1106 is distributed by the vent sheet 1102 below the preform 1104.

[0094] Now turn to Fig.12 , a top view of a second bagging layer sealed over a first bagging layer and sealed to a first tool of a molding system is shown according to an illustrative embodiment. In view 1200, the second bagging layer 1202 has been sealed to the first tool 800 by a sealing material 1204. The sealing material 1204 follows the periphery 1206 of the first tool 800. The sealing material 1204 extends around the first vacuum groove 802, the vent sheet 1102, and the first bagging layer 1002.

[0095] Now turn to Fig.13 , an illustration of a top view of a material placed onto a second molding surface of a second tool of a molding system is shown, according to an illustrative embodiment. The second tool 1300 includes a second vacuum groove 1302, a second groove 1304, and a second molding surface 1308, the second groove 1304 having a second edge 1306 configured to mold a second curved portion of a composite structure. The second tool 1300 is Figure 1 In some illustrative examples, second tool 1300 is used to Figure 2 In some illustrative examples, second tool 1300 may be used with Figure 3 In some illustrative examples, second tool 1300 may be the same as second tool 304. Figure 6 The second tool 600 is the same.

[0096] Molding surface 1310 includes second groove 1304 and second molding surface 1308 configured to mold a feature into a composite structure.

[0097] Adhesive transfer tape 1312 is placed on either side of vent sheet 1314. Adhesive transfer tape 1312 is a sealing material. Vent sheet 1314 is positioned over second molding surface 1308 and port 1316 in second molding surface 1308.

[0098] The second tool 1300 has a port 1316, a port 1318, and a port 1320. Port 1316 is located in the second vacuum groove 1302. Port 1318 is located in the second molding surface 1308. Port 1320 is located in the second groove 1304.

[0099] Ports 1316 and 1318 are used to apply a vacuum to pull the vacuum bagging layer toward the second tool 1300. Port 1320 applies a vacuum to pull the preform toward the second edge 1306.

[0100] Now turn to Fig.14 , an illustration of a top view of a sealing material placed around a second vacuum recess of a second tool of a molding system is shown according to an illustrative embodiment. In view 1400, sealing material 1402 is placed around second vacuum recess 1302. Sealing material 1402 is in contact with adhesive transfer tape 1312. Sealing material 1402 takes any desired form. In some illustrative examples, sealing material 1402 takes the form of mastic.

[0101] Now turn to Fig.15 , an illustration of a top view of a molding system with a second tool sealed to a second bagging layer above a first tool is shown in accordance with an illustrative embodiment. In view 1500, the second tool 1300 has been sealed to the second bagging layer 1202. The sealing material 1402 and the adhesive transfer tape 1312 seal the second tool 1300 to the second bagging layer 1202. In view 1500, the second tool 1300 sealed to the second bagging layer 1202 forms the molding system 1502.

[0102] Now turn to Fig.16 , a cross-sectional view of a preform between a first bagging layer and a second bagging layer is shown according to an illustrative embodiment, the first bagging layer and the second bagging layer are both sealed to a first tool of a molding system, and the second tool is sealed to the second bagging layer. Molding system 1600 is Figure 1 The molding system 102 may be used to implement a physical embodiment of the molding system 102. Figure 2 In some illustrative examples, molding system 1600 and Figure 3 In some illustrative examples, molding system 1600 is the same as molding system 300 of Fig.15 The molding system 1502 is the same.

[0103] Molding system 1600 includes first tool 1602, second tool 1604, first bagging layer 1606, and second bagging layer 1608. Preform 1610 is positioned between first bagging layer 1606 and second bagging layer 1608. First bagging layer 1606 and second bagging layer 1608 are sealed to first tool 1602. Second tool 1604 is sealed to second bagging layer 1608.

[0104] There are several cavities in molding system 1600. First bagging layer 1606 and first tool 1602 form first vacuum chamber 1612, first cavity 1614, and third vacuum chamber 1616. Second bagging layer 1608 and second tool 1604 form second cavity 1618, second vacuum chamber 1620, and second vacuum recess space 1622. A compacted region 1624 exists between first bagging layer 1606 and second bagging layer 1608. Preform 1610 exists within compacted region 1624.

[0105] Prior to molding the preform 1610, a vacuum is applied to the cavities in the molding system 1600. Prior to molding the preform 1610, a vacuum is applied to the first cavity 1614 and the second cavity 1618 through ports 1626 and 1628. The vacuum applied to the first cavity 1614 holds the first bagging layer 1606 against the first tool 1602. The vacuum applied to the second cavity 1618 holds the second bagging layer 1608 against the second tool 1604.

[0106] Prior to molding the preform 1610, a vacuum is applied to the second vacuum groove space 1622 through port 1630. Applying a vacuum through port 1630 prevents the second bagging layer 1608 from being pulled into the second vacuum chamber 1620. Prior to molding the preform 1610, a vacuum is applied through port 1632. When a sealing material is present, the area that receives the vacuum through port 1632 is referred to as the first vacuum groove space 1634. Applying a vacuum through port 1632 prevents the second bagging layer 1608 from being pulled into the first vacuum chamber 1612.

[0107] The compacted region 1624 is at least partially evacuated. By at least partially evacuating the compacted region 1624, the first tool 1602 and the second tool 1604 are clamped together. By at least partially evacuating the compacted region 1624, a portion of the preform 1610 is compacted. To at least partially evacuate the compacted region 1624, a vacuum is applied to the port 1636.

[0108] Now turn to Fig.17, a cross-sectional view of a preform formed to a first edge of a first slot of a first tool and a second edge of a second slot of a second tool is shown in accordance with an illustrative embodiment. In view 1700, vacuum is applied to first vacuum chamber 1612 and second vacuum chamber 1620 to form preform 1610 against first tool 1602 and second tool 1604.

[0109] In view 1700, vacuum has been applied to first vacuum chamber 1612 through port 1702. Vacuum has been applied to second vacuum chamber 1620 through port 1704. Port 1706 is vented to atmosphere during forming of preform 1610. Port 1706 is vented to atmosphere to control the pressure within third vacuum chamber 1616.

[0110] When a vacuum is applied to the first vacuum chamber 1612 and the second vacuum chamber 1620, the preform 1610 is formed to the first edge 1708 and the second edge 1710. In view 1700, the preform 1610 has a Z-shaped 1712 cross-section 1714.

[0111] In some illustrative examples, molding system 1600 is a schematic functional representation. For example, the location of port 1636 in molding system 1600 can be located in addition to Fig.16 and Fig.17 Another position than shown. For clarity, the cross-sectional view is shown Fig.16 The location of port 1636 in .

[0112] Figure 2-17 The different components shown in Figure 1 Used in conjunction with the components in Figure 1 Use the components in the , or a combination of the two. In addition, Figure 2-17 Some of the components in Figure 1 The components shown in block form in FIG. 1 are implemented as illustrative examples of physical structures.

[0113] exist Figure 8-17 The illustration of forming preform 1104 in the embodiment is not meant to imply physical or architectural limitations to the manner in which the exemplary embodiments may be implemented. Other components may be used in addition to or in place of the components shown. Some components may be unnecessary. For example, although the sealing of second bagging layer 1202 and first bagging layer 1002 is described as using a sealant, in other illustrative examples, second sealing layer 1202 and first sealing layer 1002 are sealed using a rubber seal or another desired sealant substitute.

[0114] Now turn to Fig.18, a diagram of a flow chart of a method for forming a composite structure is shown according to an illustrative embodiment. The method 1800 may be a method for forming a composite structure. Figure 1 The method 1800 can be used to form a composite structure 107. Figure 2 The composite structure 200 is formed. The method 1800 may be used Figure 3 The method 1800 may be performed using the molding system 300. Figure 4-5 The method 1800 may be performed using the first tool 400. Figure 6-7 The second tool 600 is used to perform. Figure 8-17 A physical depiction of the molding system when performing method 1800 may be provided.

[0115] Method 1800 forms a first bend in the cross-section of the structure into the preform by at least partially evacuating a first vacuum chamber between the first tool and the preform to pull the preform over a first feature of the first tool (operation 1802). Method 1800 simultaneously forms a second bend in the cross-section of the structure into the preform by at least partially evacuating a second vacuum chamber between the second tool and the preform to pull the preform over a second feature of the second tool positioned above the first tool (operation 1804). Thereafter, method 1800 terminates.

[0116] In some illustrative examples, the cross-section is a Z-shaped cross-section, wherein forming the first bend includes bending the preform in a first direction, and wherein forming the second bend includes bending the preform in a second direction opposite the first direction (operation 1818).

[0117] In some illustrative examples, a first vacuum chamber between the first tool and the preform is a chamber formed by the first bagging layer and the first tool, wherein a second vacuum chamber between the second tool and the preform is a chamber formed by the second bagging layer and the second tool. In some illustrative examples, method 1800 simultaneously draws a vacuum in a first cavity formed by the first bagging layer sealed to the first tool and a second cavity formed by the second bagging layer sealed to the second tool, wherein the first bagging layer is positioned between the preform and the first tool, and wherein the second bagging layer is positioned between the preform and the second tool (operation 1812). In some illustrative examples, method 1800 evacuates vacuum recesses of the first tool and the second tool, thereby clamping the second bagging layer to the first tool after simultaneously drawing vacuums in the first cavity and the second cavity, and clamping the second bagging layer to the second tool (operation 1814).

[0118] In some illustrative examples, process 1800 evacuates the cavity between the first bagging layer and the second bagging layer, thereby clamping the first tool and the second tool together and compacting a portion of the preform (operation 1816 ).

[0119] In some illustrative examples, method 1800 seals the first bagging layer to the first tool to form a first vacuum chamber, a first cavity, and a third vacuum chamber (operation 1806). In some illustrative examples, method 1800 seals the second bagging layer to the first tool to form a compaction region (operation 1808). In some illustrative examples, method 1800 seals the second bagging layer to the second tool to form a second vacuum chamber, a second cavity, and a second vacuum recess space (operation 1810).

[0120] In some illustrative examples, the preform is a prepreg material, and method 1800 includes, after simultaneously forming the first bend and the second bend, heating the preform to set the cross-section (operation 1820 ).

[0121] Now turn to Fig.19 , shows an illustration of a flow chart of a method for forming a structure according to an illustrative embodiment. The method 1900 may be to Figure 1 Method 1900 can be used to form a composite structure 107. Figure 2 The composite structure 200 is formed. The method 1900 may be used Figure 3 The method 1900 may be performed using the molding system 300. Figure 4-5 The method 1900 may be performed using the first tool 400. Figure 6-7 The second tool 600 is used to perform. Figure 8-17 A physical depiction of the molding system when performing method 1900 may be provided.

[0122] The method 1900 seals a first bagging layer to a first tool (operation 1902). The method 1900 seals the second bagging layer to the first tool when the preform is between the first bagging layer and the second bagging layer (operation 1904). The method 1900 seals the second tool to the second bagging layer (operation 1906). The method 1900 at least partially evacuates a first vacuum chamber formed by the first bagging layer and the first tool, while at least partially evacuating a second vacuum chamber formed by the second bagging layer and the second tool to simultaneously mold the preform to a molding surface of the first tool and a molding surface of the second tool (operation 1908). Thereafter, the method 1900 terminates.

[0123] In some illustrative examples, method 1900 simultaneously draws a vacuum in a first cavity formed by a first bagging layer sealed to a first tool and a second cavity formed by a second bagging layer sealed to a second tool to clamp the first bagging layer to the first tool and the second bagging layer to the second tool (operation 1910). As shown, the simultaneous drawing of vacuums in the first cavity and the second cavity is performed before at least partially evacuating the first vacuum chamber and the second vacuum chamber. By clamping the first bagging layer to the first tool and the second bagging layer to the second tool, the bagging layers are prevented from being pulled into a first slot of the first tool and a second slot of the second tool.

[0124] In some illustrative examples, method 1900 draws a vacuum in a first vacuum groove of a first tool to clamp the second bagging layer to the first tool (operation 1912). In some illustrative examples, method 1900 draws a vacuum in a second vacuum groove of a second tool to clamp the second bagging layer to the second tool (operation 1914). Clamping the second bagging layer to the second tool prevents the second bagging layer from moving into the second groove of the second tool.

[0125] In some illustrative examples, method 1900 at least partially evacuates the cavity between the first bagging layer and the second bagging layer to clamp the first tool and the second tool together and compact the portion of the preform (operation 1916). In some illustrative examples, compacting the portion of the preform forms a web of the composite structure having a Z-shaped cross-section.

[0126] In some illustrative examples, the preform is a prepreg material, and method 1900 heats the preform to set the cross-section after simultaneously molding the preform to the molding surface of the first tool and the molding surface of the second tool (operation 1918). In some illustrative examples, the molding system is placed in an oven or an autoclave to heat the preform.

[0127] As used herein, the phrase "at least one of" when used with a list of items means that different combinations of one or more of the listed items can be used, and only one of each item in the list may be required. In other words, "at least one of" means that any combination of items and quantities of items in the list may be used, but not all items in the list are required. The item may be a specific object, thing, or category.

[0128] For example, "at least one of item A, item B, or item C" may include, but is not limited to, item A, item A and item B, or item B. This example may also include item A, item B, item C, or item B and item C. Of course, any combination of these items may exist. In other examples, "at least one of" may be, for example, but not limited to: two of item A, one of item B, and ten of item C; four of item B and seven of item C; or other suitable combinations.

[0129] The flowcharts and block diagrams in the depicted different embodiments show the architecture, functionality and operation of some possible implementations of the apparatus and methods in the illustrative embodiments. In this regard, each box in the flowchart or block diagram may represent a module, segment, function and / or a part of an operation or step.

[0130] In some alternative implementations of the illustrative embodiments, one or more functions noted in the blocks may not occur in the order noted in the figure. For example, in some cases, two blocks shown in succession may be performed substantially simultaneously, or the blocks may sometimes be performed in the reverse order, depending on the functions involved. Moreover, in a flow chart or block diagram, other blocks may be added in addition to the blocks shown. Some blocks may be optional. For example, Fig.18 Operations 1806 to 1820 may be optional. As another example, Fig.19 Operations 1910 to 1918 may be optional.

[0131] Illustrative embodiments of the present disclosure may be used in Fig. 20 Aircraft manufacturing and service method 2000 and Fig.21 2100 is described in the context of the aircraft shown in FIG. Fig. 20 , an illustration of an aircraft manufacturing and service method is depicted according to an illustrative embodiment. During pre-production, aircraft manufacturing and service method 2000 may include Fig.21 Specification and Design of Aircraft 2100 2002 and Material Procurement 2004.

[0132] During production, component and subassembly manufacturing 2006 and system integration 2008 of the aircraft 2100 occurs. Thereafter, the aircraft 2100 may undergo certification and delivery 2010 in order to be placed into service 2012. While in service 2012 by a customer, the aircraft 2100 is scheduled for routine maintenance and service 2014, which may include modification, reconfiguration, refurbishment, or other maintenance and service.

[0133] Each process of aircraft manufacturing and service method 2000 can be performed or implemented by a system integrator, a third party, and / or an operator. In these examples, the operator can be a customer. For the purpose of this description, a system integrator can include, but is not limited to, any number of aircraft manufacturers and major system subcontractors; a third party can include, but is not limited to, any number of sellers, subcontractors, and suppliers; and an operator can be an airline, a leasing company, a military entity, a service organization, etc.

[0134] Reference now Fig.21 , depicts a diagram of an aircraft in which an illustrative embodiment may be implemented. In this example, aircraft 2100 is traveling through Fig. 20 Aircraft manufacturing and service method 2000 is produced and may include airframe 2102 having multiple systems 2104 and interior 2106. Examples of systems 2104 include one or more of propulsion system 2108, electrical system 2110, hydraulic system 2112, and environmental system 2114. Any number of other systems may be included.

[0135] Apparatus and methods embodied herein may be employed during at least one of the stages of aircraft manufacturing and service method 2000. Fig. 20 One or more illustrative embodiments may be used during at least one of component and subassembly manufacturing 2006, system integration 2008, or maintenance and service 2014 of an aircraft 2100. For example, the illustrative examples may be used during component and subassembly manufacturing 2006 to assemble a composite stiffener (e.g., composite structure 107). For example, method 1800 may be used during component and subassembly manufacturing 2006 to form Z-shaped 172 cross-section 174 in composite structure 107. Method 1800 may be used to manufacture a portion of fuselage 2102 of aircraft 2100. As another example, method 1900 may be used during component and subassembly manufacturing 2006 to form Z-shaped 172 cross-section 174 in composite structure 107. Method 1900 may be used to manufacture a portion of fuselage 2102 of aircraft 2100.

[0136] The illustrative examples provide a cost-effective means of manufacturing complex shapes into composite structures. In one illustrative example, a Z-shaped cross section is produced in a reinforcing bar. The illustrative examples reduce labor costs. The illustrative examples achieve higher deposition rates through flat lay-ups, which can potentially be automated. The illustrative examples enable increased productivity of composite structures with complex cross-sections.

[0137] In addition, this disclosure includes examples according to the following clauses:

[0138] Item 1. A molding system configured to mold a composite structure, the molding system comprising: a first tool comprising a first vacuum groove, a first groove, and a first molding surface, the first groove having a first edge configured to mold a first bend of the composite structure; and a second tool comprising a second vacuum groove, a second groove, and a second molding surface, the second groove having a second edge configured to mold a second bend of the composite structure.

[0139] Clause 2. The molding system of Clause 1, wherein the first vacuum groove has a C-shape extending around a portion of the first slot.

[0140] Clause 3. The molding system of Clause 1, wherein the second vacuum groove has a C-shape extending around a portion of the second slot.

[0141] Item 4. The molding system of Item 1, further comprising: a first bagging layer sealed to the first tool between the first vacuum groove and the first groove such that the first bagging layer extends over the first groove; and a second bagging layer sealed to the first tool such that the second bagging layer extends over the first vacuum groove and the first groove.

[0142] Clause 5. The molding system of Clause 4, wherein the second tool is sealed to the second bagging layer over the first molding surface of the first tool.

[0143] Clause 6. The molding system of Clause 5, wherein the second tool is sealed to the second bagging layer such that the second groove faces the first molding surface.

[0144] Clause 7. The molding system of Clause 4, wherein the first bagging layer and the first tool form a first vacuum chamber, a first cavity, and a third vacuum chamber.

[0145] Clause 8. The molding system of Clause 7, wherein the second bagging layer and the second tool form a second vacuum chamber, a second cavity, and a second vacuum recess space.

[0146] Clause 9. The molding system of Clause 8, wherein the first tool, the first bagging layer, and the second bagging layer form a compacted region.

[0147] Item 10. A method of forming a structure, the method comprising: forming a first bend in the cross-section of the structure into the preform by at least partially evacuating a first vacuum chamber between a first tool and the preform, pulling the preform over a first feature of the first tool; and forming a second bend in the cross-section of the structure into the preform by at least partially evacuating a second vacuum chamber between a second tool and the preform, pulling the preform over a second feature of the second tool positioned above the first tool.

[0148] Clause 11. The method of clause 10, wherein the cross section is a Z-shaped cross section, wherein forming the first bend comprises bending the preform in a first direction, and wherein forming the second bend comprises bending the preform in a second direction opposite to the first direction.

[0149] Clause 12. A method according to clause 10, wherein the first vacuum chamber between the first tool and the preform is a chamber formed by a first bagging layer and the first tool, and wherein the second vacuum chamber between the second tool and the preform is a chamber formed by a second bagging layer and the second tool, the method further comprising: simultaneously drawing a vacuum in a first cavity formed by the first bagging layer sealed to the first tool and a second cavity formed by the second bagging layer sealed to the second tool, wherein the first bagging layer is positioned between the preform and the first tool, and wherein the second bagging layer is positioned between the preform and the second tool; and evacuating the vacuum grooves of the first tool and the second tool, thereby clamping the second bagging layer to the first tool and clamping the second bagging layer to the second tool after the vacuum is simultaneously drawn in the first cavity and the second cavity.

[0150] Clause 13. The method of Clause 12, further comprising: evacuating a cavity between the first bagging layer and the second bagging layer to clamp the first tool and the second tool together and compact a portion of the preform.

[0151] Clause 14. The method of clause 10, further comprising: sealing a first bagging layer to the first tool to form the first vacuum chamber, a first cavity, and a third vacuum chamber; sealing a second bagging layer to the first tool to form a compaction area; and sealing the second bagging layer to the second tool to form the second vacuum chamber, a second cavity, and a second vacuum recess space.

[0152] Clause 15. The method of Clause 10, wherein the preform is a prepreg material, the method further comprising: heating the preform to set the cross-section after simultaneously forming the first bend and the second bend.

[0153] Item 16. A method of forming a cross-section of a structure, comprising: sealing a first bagging layer to a first tool; sealing the second bagging layer to the first tool when a preform is between the first bagging layer and the second bagging layer; sealing a second tool to the second bagging layer; and at least partially evacuating a first vacuum chamber formed by the first bagging layer and the first tool while at least partially evacuating a second vacuum chamber formed by the second bagging layer and the second tool to simultaneously form the preform to a forming surface of the first tool and a forming surface of the second tool.

[0154] Clause 17. The method of claim 16, further comprising: simultaneously drawing a vacuum in a first cavity formed by the first bagging layer sealed to the first tool and a second cavity formed by the second bagging layer sealed to the second tool, thereby clamping the first bagging layer to the first tool and clamping the second bagging layer to the second tool, wherein a vacuum is simultaneously drawn in the first cavity and the second cavity before at least partially evacuating the first vacuum chamber and the second vacuum chamber.

[0155] Clause 18. The method of Clause 17, further comprising: drawing a vacuum in a first vacuum groove of the first tool to clamp the second bagging layer to the first tool; and drawing a vacuum in a second vacuum groove of the second tool to clamp the second bagging layer to the second tool.

[0156] Clause 19. The method of Clause 18, further comprising at least partially evacuating a cavity between the first bagging layer and the second bagging layer to clamp the first tool and the second tool together and compact a portion of the preform.

[0157] Clause 20. The method of Clause 16, wherein the preform is a prepreg material, the method further comprising heating the preform to set the cross-section after simultaneously molding the preform to the molding surface of the first tool and the molding surface of the second tool.

[0158] For the purpose of illustration and description, descriptions of different illustrative embodiments have been given, and are not intended to be exhaustive or limited to the embodiments of the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. In addition, different illustrative embodiments may provide different features compared to other illustrative embodiments. The selected one or more embodiments are selected and described in order to best explain the principles of the embodiments, practical applications, and to enable other persons of ordinary skill in the art to understand the disclosure of various embodiments with various modifications suitable for the particular use under consideration.

Claims

1. A molding system configured to shape a composite structure, the molding system comprising: a first tool comprising a first vacuum groove, a first slot having a first edge configured to mold a first bend of the composite structure, and a first molding surface; a second tool comprising a second vacuum groove, a second slot having a second edge configured to mold a second bend of the composite structure, and a second molding surface; a first bagging layer sealed to the first tool between the first vacuum recess and the first slot such that the first bagging layer extends over the first slot; as well as a second bagging layer sealed to the first tool such that the second bagging layer extends over the first vacuum recess and the first slot; The first bagging layer and the first tool form a first vacuum chamber, a first cavity and a third vacuum chamber. 2 . The molding system of claim 1 , wherein the first vacuum groove has a C-shape extending around a portion of the first slot. 3 . The molding system of claim 1 , wherein the second vacuum groove has a C-shape extending around a portion of the second slot.

4. The molding system of claim 1, wherein the second tool is sealed to the second bagging layer over the first molding surface of the first tool. 5 . The molding system of claim 4 , wherein the second tool is sealed to the second bagging layer such that the second groove faces the first molding surface.

6. The molding system of claim 1, wherein the second bagging layer and the second tool form a second vacuum chamber, a second cavity, and a second vacuum recess space.

7. The molding system of claim 6, wherein the first tool, the first bagging layer, and the second bagging layer form a compacted region.

8. A method of forming a structure, the method comprising: pulling the preform over a first feature of the first tool by at least partially evacuating a first vacuum chamber between the first tool and the preform, thereby forming a first curvature of the cross-section of the structure into the preform; pulling the preform over a second feature of the second tool positioned above the first tool by at least partially evacuating a second vacuum chamber between the second tool and the preform, thereby forming a second curvature of the cross-section of the structure into the preform; sealing a first bagging layer to the first tool to form the first vacuum chamber, a first cavity, and a third vacuum chamber; sealing a second bagging layer to the first tool to form a compacted area; as well as The second bagging layer is sealed to the second tool to form the second vacuum chamber, a second cavity, and a second vacuum recess space.

9. The method of claim 8, wherein the cross-section is a Z-shaped cross-section, wherein forming the first bend comprises bending the preform in a first direction, and wherein forming the second bend comprises bending the preform in a second direction opposite to the first direction.

10. The method of claim 8, wherein the first vacuum chamber between the first tool and the preform is a chamber formed by a first bagging layer and the first tool, wherein the second vacuum chamber between the second tool and the preform is a chamber formed by a second bagging layer and the second tool, the method further comprising: simultaneously drawing a vacuum in a first cavity formed by the first bagging layer sealed to the first tool and a second cavity formed by the second bagging layer sealed to the second tool, wherein the first bagging layer is positioned between the preform and the first tool, and wherein the second bagging layer is positioned between the preform and the second tool; and The vacuum recesses of the first tool and the second tool are evacuated, thereby clamping the first bagging layer to the first tool and the second bagging layer to the second tool after the vacuum is simultaneously drawn in the first cavity and the second cavity.

11. The method according to claim 10, further comprising: The cavity between the first bagging layer and the second bagging layer is evacuated to clamp the first tool and the second tool together and compact a portion of the preform.

12. The method of claim 8, wherein the preform is a prepreg material, the method further comprising: After the first and second bends are simultaneously formed, the preform is heated to set the cross section.

Images