摘要:
A method for producing a bicycle wheel rim having an inner peripheral wall, an outer peripheral wall, two lateral walls joining said peripheral walls, and two circumferential wings, for anchoring a tire, is provided. The method providing a rim made of a single part made of structural fiber based material, preferably carbon fiber material.
摘要:
A process for manufacturing pre-cured parts of composite material with green-applied stiffeners, comprising the lamination of superimposed pre-impregnated composite material sheets to obtain a base part (1) and a second part (2) intended to be bonded with it; curing the base part (1); hot forming the laminate destined to form the second part (2); removing the second part (2) from the forming tool thereof and deposit it over the base part (1), intercalating a structural adhesive sheet between both of them; closing the assembly of both parts inside a vacuum bag and loading said bag in an autoclave, carrying out a curing cycle of the second part (2) under pressure and temperature, so that it is strongly adhered to the base part (1). The invention is applicable to the field of aeronautics.
摘要:
A flexible tool that fits over the pressure or concave side of a metallic airfoil that includes a lightweight material component for a gas turbine engine during the fabrication of the airfoil. The metallic fan airfoil includes pockets or cavities that have been machined into the airfoil in order to reduce the weight of the airfoil. The tool is a flexible body manufactured from sheets of composite material and includes an integral elastomeric seal. The tool is placed over the airfoil and forms a seal against the pressure side of the airfoil so that lightweight resin can be injected into the pockets and retained in position during curing. The flexible tool is formed by laying up thin sheets of composite material that includes fiber over a metallic master tool after partially cured elastomeric material is placed inside a marking corresponding to the airfoil perimeter. The metallic master tool also includes slot positions corresponding to preselected positions, that form integral projections which allow the flexible tool to be correctly assembled and sealed against the airfoil.
摘要:
A definitive socket for residual limb prosthetic use is formed in a single molding step by compressive pressure casting or molding a pre-formed, moldable, hardenable socket material over a residual limb and curing the socket material to a load-bearing hardened condition while it is maintained under peripheral compressive pressure against the residual limb and while the residual limb is tensioned in a distal direction during the casting process. The combination of pressure casting the socket material and applying tension to the residual limb in a distal direction while the socket material is curing results in forming a definitive socket that fits well to the residual limb after curing without substantial rectification. Pressure relief formations, socket coverings, and a prosthesis coupler may be compression molded simultaneously with the socket.
摘要:
The invention refers to a plant and a holding device in connection with heat treatment of articles (3), which is at least partly manufactured in a thermosetting composite material. The holding device, which is comprised by the plant, includes a base element (1), and intermediate element (2), which rests on the base element (1), and at least a support member (4), which is fixable to the intermediate element (2) and arranged to support said article (3) on the intermediate element during the heat treatment. The intermediate element (2) is manufactured in a material which has a neglectable thermal extension at least up to a temperature level, at which the heat treatment is intended to take place. Furthermore, the intermediate element (2) is displaceably positioned on the base element (1).
摘要:
A method of making a composite part includes the steps of placing a first section of a fibrous pre-form in a mold and infusing the first section of the fibrous pre-form with a resin so as to produce a resin-infused portion and a non-resin-infused portion. Next, the method includes coupling the non-resin-infused portion to a second section of the fibrous pre-form to create a coupled non-resin-infused portion. Then, the coupled non-resin-infused portion is infused with resin to create a second resin-infused portion and a second non-resin-infused portion. These steps are repeated to separately infuse different sections of the part until the part is complete. The corresponding apparatus preferably employs a rigid mold having a shape defining only a portion of the composite part to be made. And, the method is particularly adapted to making both cored and non-cored structures that are large or unconventionally shaped.
摘要:
A method for fabricating fiber reinforced plastic structures includes a mold surface upon which can be supported a lay-up of one or more layers of a fibrous material, and over which can be placed a fluid impervious outer sheet with an inlet port and having its edges marginally sealed upon the mold surface to form a chamber. A vacuum outlet is connected to the chamber for drawing a vacuum there from. A resin distribution system is positioned between the lay-up and the fluid impervious sheet. The resin distribution system includes a resin distribution medium for receiving resin from the inlet port and a resin containment layer between the resin distribution medium and lay-up for preventing resin flowing from the resin distribution medium into the lay-up until the resin distribution medium is substantially filled with resin.
摘要:
In a process for producing large-surface structural elements from fiber-reinforced composite materials by resin transfer moulding, a mold (2) that can be evacuated has a dimensionally stable part (4) and an elastically deformable part (6). The mold (2) has connections for injecting a resin mixture and connections to a pressure sink. A fibrous fabric (12) is set into the mold (2). Elongated pipes having a large supporting surface (22) and a cavity (24) that extends in the longitudinal direction of the pipes above the supporting surface (22) are provided on the surface of the fibrous fabric (12) opposite to the dimensionally stable mold part (4) to inject the resin mixture and to ensure the connection with the pressure sink. The supporting surface (22) of the pipes has a narrow slit (26) which extends substantially over the whole length of the pipes and which is in communication over its whole length with the cavity (24). At least one end of the pipes extends outwards through the edges of the elastically deformable and dimensionally stable mold parts and is linked to the resin supply pipe or to the pressure sink. The mold (2) is evacuated down to an inner pressure of less than 50 hPa.
摘要:
A tooling concept uses a compliant forming surface for forming composite parts. The tooling concept utilizes a rigid support substructure that has a thin compliant forming surface. In the preferred embodiment of the invention, the tooling concept is used to form a composite sine wave spar. A preferred embodiment of the tooling concept includes upper and lower tool inserts and side tool inserts. The upper tool insert has a compliant forming surface that is located in between a rigid support substructure and the composite material used to form the composite part. Composite prepreg is laid up over a sine wave contour on the upper and lower tool inserts to form upper and lower U-shaped composite workpieces. The upper and lower tool inserts and workpieces are then brought together to form a sine wave I-beam. Radius fillers are then applied to the intersections between the upper and lower composite workpieces and cap strips are placed over the flanges of the joined composite workpieces. Side tools and end tools are then placed around the joined upper and lower tool inserts. The resulting assembly is covered with a breather cloth, baked in a vacuum bag and cured in an autoclave. During curing, the autoclave applies a hydrostatic pressure on the upper tool insert and thus compliant forming surface. The compliant forming surface in turn applies a consolidation and forming pressure to the composite workpiece within the tools. During curing, the compliant forming surface deforms slightly to account for thickness variations in the composite workpiece in order to produce a better quality formed composite part.
摘要:
A method for making grid-stiffened structures as provided. The method includes providing a base tool having a plurality of grooves and an expansion tool having a plurality of compaction grooves therein for fitting into a plurality of the base tool grooves so as to define compaction grooves therein. A plurality of prepreg tows are then wound into the compaction grooves. A skin is then placed over the so-wound tows, the expansion tool and the base tool to define an assembly. The assembly is then bagged and autoclaved so that the expansion tool expands to provide lateral pressure to compact the prepreg tows in the compaction grooves to shape same into ribs to form a rib-stiffened structure. An analytical thermal model is developed to predict the behavior of the expansion tool.