69 results about "Vacuum assisted resin transfer molding" patented technology

A process and apparatus for producing fiber reinforced resin structures using vacuum assisted resin transfer molding technology, wherein the apparatus and process employ a first fluid impervious flexible sheet containing therein a resin port; a fiber containing preform; a primary vacuum line; a resin channeling means; and a secondary vacuum line. The fluid impervious flexible sheet is placed over or around the fiber containing preform to form a chamber to which the primary vacuum line is connected. The resin channeling means is positioned on top of the fluid impervious flexible sheet, exterior to the chamber containing the preform in a fashion so as to form a pocket between or around the resin channeling means and said fluid impervious flexible sheet to which the secondary vacuum is applied. Activation of the secondary vacuum causes formation of channels in the fluid impervious flexible sheet. These channels increase the speed and efficiency of resin impregnation of the fiber containing preform.

Vacuum assisted resin transfer molding techniques are improved by mounting a rigid external shell on top of a vacuum bag. The shell is sealed around the vacuum bag so that a vacuum is created between the shell and the vacuum bag, the vacuum causes the vacuum bag to be freely stretched and lifted away from the preform to create a flow flooding chamber which provides a flow channel on the top face of the preform to accelerate the resin flow and reduce the injection time.

According to one embodiment of the invention, a co-cured vacuum-assisted resin transfer molding manufacturing method includes providing a tool base, disposing a prepreg skin panel outwardly from the tool base, disposing one or more tooling details outwardly from the prepreg skin panel, and disposing one or more preforms proximate the one or more tooling details. The one or more preforms are either dry or binderized. The method further includes disposing a high permeability medium between the one or more tooling details and the one or more preforms, enclosing the prepreg skin panel, the one or more tooling details, the one or more preforms, and the high permeability medium with at least one vacuum bag, pulling a vacuum on the vacuum bag, infusing the one or more preforms with a resin, and curing the one or more preforms and the prepreg skin panel.

A method for vacuum assisted resin transfer molding a composite structure including fibers at least partially surrounded by resin using a mold including a tool having a surface shaped to correspond to the composite structure and an inflatable bladder for forcing the composite structure against the tool. A resin inlet is connected to a resin source for introducing resin into a mold cavity at least partially defined by the tool surface and the bladder and a vacuum port spaced from the resin inlet. The method includes the steps of opening the mold cavity, loading fibers into the open mold cavity, closing the loaded mold cavity, introducing resin through the resin inlet into the closed mold cavity loaded with fibers, and pulling a vacuum at the resin inlet and the vacuum port to draw excess resin from the structure prior to curing thereof.

A method and apparatus for a reusable resin distribution line for use in conjunction with a resin transfer molding apparatus is disclosed. The apparatus includes a soft tool and a hard tool (i.e., mold). In the illustrative embodiment, two inflatable bladders are disposed on a side of the soft tool, wherein a bridge spans the bladders. The soft tool is coupled to the bridge. When the bladders are inflated, the bridge moves away from the hard tool, drawing the soft tool away from the hard tool in the region between the bladders. This creates a temporary passage or reusable resin distribution line for distributing resin to a reinforcement constituent disposed between the soft tool and the hard tool.

The present invention provides a process for forming a composite material. The present invention further provides methods of improving the fiber volume fraction and/or the dimensional thickness of a composite panel.

The invention discloses a vacuum assisted resin transfer molding integral-forming technology of a composite material fuel-tank. A novel structural material fuel-tank is provided. Structural weight of a present fuel tank and vehicle noise level can be reduced effectively, and the novel structural material fuel-tank has characteristics of impact damage resistance, corrosion resistance and the like. Meanwhile, forming process cycle of the fuel tank can be greatly shortened, and production efficiency of the fuel tank can be raised. The technology is realized by the following technical scheme: core three-dimensional modeling; core forming-die manufacturing; soluble (fusible) core manufacturing; die preparation; laying and shaping of a reinforcing material; die locking; making of a resin solution; resin injection; resin curing; demoulding; core dissolution (fusing); and composite material product finishing. By the technology, production efficiency is high; demoulding is convenient; and cost is low.

The invention relates to a composite material of sandwich structure with an elastic core material. The composite material consists of upper and lower composite material panels and a porous elastic core material (1) positioned between the upper and lower composite material panels, which are stitched by fiber yarns (3) passing through holes of the elastic core material, wherein the composite material panels are made of fiber cloths (2) and matrix resins of the composite material. The method for preparing the composite material comprises the following steps: drilling holes on the elastic core material (1) at intervals, laying the fiber cloths (2) on the upper surface and the lower surface of the elastic core material, and making the fiber yarns (3) pass through the holes of the core material by a straight stitching lock type stitching method, to make the core material and the fabric cloths into a whole; making the resin soak the fabric cloths and the holes of the core material by the vacuum assisted resin transfer molding; and finally, solidifying and molding the whole by solidification technology, to obtain the composite material. The material has excellent performance, novel structure and simple preparation technology, is easy to operate, and is applicable to the industrialized production.

Thickness gradients in large, cobonded composite structures resulting from gravity-induced resin migration during curing is substantially reduced by rotating the structure during the resin infusion and curing stages. The layup for the structure is placed on a rotatable tool fixture and vacuum bagged. The tool fixture is mounted on a central support tube provided with motors for rotating the tool fixture about the axis of the tube. The tube has internal passageways that deliver resin to the bagged layup and carry away excess resin from the layup using vacuum pressure. The resulting composite structures exhibit thickness gradients less than 10%.

The invention belongs to the technical field of machining of railway traffic equipment, particularly relates to a fiber-enhanced light interlayer composite material and further discloses a subway cockpit body prepared from the same. The fiber-enhanced light interlayer composite material is of an integral structure integrally formed by taking a fiber-enhanced resin composite material as a skin material and foam with a three-dimensional net as an interlayer material through a vacuum-assisted resin transfer molding process, has the advantages of light weight, high structural strength, good shockresistance and environment friendliness and can be used for processing and preparing large-scale complex components such as the subway cockpit body. The subway cockpit body is prepared by taking the fiber-enhanced light interlayer composite material as a main body material and has the performance advantages of light weight, high structural strength and good shock resistance.

A method and an apparatus for molding composite articles are disclosed. The method generally involves the saturation of reinforcing fibers (e.g. glass fibers, carbon fibers, etc.) with a matrix (e.g. resin, epoxy, cyanate ester, vinyl ester, polyester, etc.) in/on a mold using a conventional resin transfer molding (“RTM”) process (e.g. “RTM-light”) or a vacuum assisted resin transfer molding (“VARTM”) process (e.g. advanced VARTM or “A-VARTM”), and, once saturation is completed, the vibration of the matrix-infused fibers using controlled ultrasonic sound waves transmitted through the mold. By vibrating the matrix-infused fibers with the ultrasonic sound waves, the method and apparatus allow voids present between fibers to be closed and localized pockets of gases to be dislodged and degassed, and also allow the fibers to compact, thereby producing composite articles with reduced porosity and higher compaction.

A spar platform comprises one or more continuous-fiber composite tubes fabricated at or near the intended site use of the platform. In some embodiments, the spar platform includes a relatively longer central tube and relatively shorter peripheral tubes. In some other embodiments, the spar platform is a single long tube. In some embodiments, the spar platform supports a wind turbine assembly. The continuous-fiber composite tubes are formed, in either a vertical or horizontal orientation, using a modified vacuum assisted resin transfer molding process.

The invention discloses a method for making a membrane for use as a vacuum bag, a natural rubber vacuum bag made using such methods, and methods for using such a natural rubber bag to form a composite article. One method can include providing a substantially non-porous working surface having a desired shape for forming a vacuum bag, spraying at least one layer of a natural rubber liquid over at least a portion of working surface, and solidifying the natural rubber liquid to form a membrane having a shape substantially corresponding to that of the working surface. The membrane formed being elastically deformable and substantially impermeable for functioning as a vacuum bag in Vacuum Assisted Resin Transfer Molding, debulking, compaction, or similar processes.

A method of preparing a mould having a moulding cavity surface with vacuum flow topology for vacuum resin transfer moulding is provided. This method includes: pressing a number of peel ply layers into an uncured resin layer for building up the moulding cavity surface, curing the resin of the resin layer, and detaching the peel ply layers to generate the vacuum flow topology in the moulding cavity surface. A mould for wind turbine blades having a vacuum flow topology prepared by such a method is also provided.

The invention provides a composite lattice structure and a preparation method. The composite lattice structure is composed of an upper face plate, a lower face plate and a lattice core arranged between the upper face plate and the lower face plate. The lattice core is formed in the manner that lattice core triangular fibers and trapezoidal fibers are interlaced. Foam interlayers are arranged in the upper face plate and the lower face plate. A specific injection manner is applied to the composite lattice structure for VARTM formation. The preparation method of the composite lattice structure comprises the seven steps of (1) preparing a fusible alloy mold core; (2) inserting the triangular fibers; (3) laying fibers on the bottom layers of the upper face plate and the lower face plate; (4) inserting the trapezoidal fibers; (5) arranging the face plate interlayers and laying surface fibers of the face plates; (6) conducting VARTM (vacuum assisted resin transfer molding) formation; (7) heating and melting the fusible alloy mold core. The composite lattice structure and the preparation method effectively solve the connection problem between a composite lattice core and the face plates, integrated formation is achieved, the quality is reliable, the technology is simple, and the node strength is high.

The invention provides a manufacturing method of a three-dimensional woven composite material hollow spiral spring. The manufacturing method comprises the following steps: first, using spinnable and weavable fiber to weave a three-dimensional braidd tube on the outer surface of a bent strip-type core model through the three-dimensional weaving technology so as to obtain a strip-type fabric preform; then, placing the strip-type fabric preform in a spiral space formed between an internal model and an external model; next, injecting basis material in the spiral space by adopting the vacuum assisted resin transfer molding process (VARTM), and adopting warming and pressurization to solidify the basis material and the three-dimensional braidd tube into the composite material spiral spring; and finally, removing the core model in the spiral spring to obtain the three-dimensional woven composite material hollow spiral spring. The three-dimensional woven composite material hollow spiral springmanufactured through the manufacturing method has the advantages of light weight, antifatigue, corrosion resistance and impact resistance of the composite material spiral spring to further improve theperformance including light weight and spring rigidity.