Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

Improved composite fibers, and structural materials mixed with the improved composite fibers, are produced by an improved process that vertically texturizes and impregnates resin into the fibers without introducing any substantial amount of microbubbles in the resin. By using vertical impregnation and twisting of fiber strands with specific viscosity control, stronger composite fibers, in which substantially no microbubbles are trapped, are produced with improved tensile strength and lower variance in tensile strength, for use in strengthening structural concrete and other structural materials.

A method and an extrusion- or pultrusion device (1) for forming a profile product (2) made from a material in a production direction (Y), said device comprising: a rotating die (3), extending in a radial (R) direction and a width direction (X), having two opposite first and second side walls (5, 6) and an outer circumferential surface (4) extending in the width direction (X) there between, wherein the rotating die (3) comprises a first side portion (23) in connection to the first side wall (5) and a second side portion (25) in connection to the second side wall (6) and a mid-portion (22) extending between the first and second side portions (23, 25), and a profile definition zone (7) having a longitudinal direction (Y) coinciding with the production direction (Y), a height direction (Z) and a width direction (X) being perpendicular to the height direction (Z), comprising a through channel (8) comprising a first channel section (9) followed by a second channel section (10) downstream the first channel section (9) with reference to the production direction,
wherein the rotating die (3) is rotatable about an axis extending across the production direction (Y) and arranged to allow the outer circumferential surface (4) to, while the rotating die (3) rotates, exert a pressure onto a surface of the material when fed through the profile definition zone (7).

A system for pultruding a beam, such as a pultruded beam of natural fibers, comprises a pulling mechanism continuously pulling on a preform of yarns including a thermoplastic matrix and fibers, the pulling mechanism being downstream of the system. A sequence is provided in the system and has a pre-heating module to pre-heat the preform. A first die has a tapering channel portion heated such that the preform reaches a desired low viscosity temperature for resin in the thermoplastic matrix to impregnate the fibers. A vacuum module has a vacuum cavity to remove air from the preform exiting the first die. A second die has a tapering channel portion heated such that the preform is at the desired low viscosity temperature for resin in the thermoplastic matrix to further impregnate the fibers. A cooling module to cool the beam before the beam reaches the pulling mechanism. A system for pultruding beams is also provided.

A pultrusion device and method are provided for producing a fiber-reinforced continuous section which has a second cross-sectional profile that is discontinuous in a direction of pultrusion with a press forming device for shaping the continuous section. The press forming device includes a first shaping device for producing the continuous section with a continuous cross-sectional profile and a second shaping device, which follows on from the first shaping device in the direction of pultrusion, for shaping the second discontinuous cross-sectional profile of the continuous section. A punching tool is arranged between the first shaping device and the second shaping device and is designed to bring about a local change in shape of the continuous cross-sectional profile, at least in a defined portion of the continuous section, in order to produce a first discontinuous cross-sectional profile of the continuous section.

A method for forming a multi-layered structure includes forming a resin-infused fibrous material (70) by applying a liquid resin component (60) onto the fibrous material (32) being pulled through an injection box (110) such that the fibrous material is partially impregnated and surrounded by the liquid resin component to form a resin-infused fibrous material. The resin-infused fibrous material is then introduced to a first die (130) and partially cured to form a partially-cured fiber-reinforced core material (80). The core material exits the first die to an intermediate region, where a polymer layer (40) is then applied onto at least a portion of the outer profile surface of the core material. The material then enters a second die (140), where the liquid resin component is fully cured to form a fiber-reinforced thermoset core material (30) having the polymer layer adhered thereon within the second die, thus forming the multi-layered structure (20).

An alternating pressure melt impregnation device and a melt impregnation method, including having a resin melt squirted from each resin melt runner on an upper die and a lower die of a melt injection area, and thus the squirted resin melt is enable to be squirted directly on an upper surface and a lower surface of a continuous fiber bundle which is entering into an impregnation chamber. Impregnation and infiltration for both surfaces of the continuous fiber bundle are primarily completed by a squirted pressure. The resin melt inside the impregnation chamber flows to a decompression chambers at both sides of the impregnation chamber. When the resin melt flows to a throttle plate, a re-impregnation for the continuous fiber bundle is realized. Then the pressure is decreased and a section of the resin melt is enlarged and a radial flow is generated due to the Barus effect.

Systems and methods are provided for fabricating preforms. One embodiment is a method comprising acquiring tows of fiber reinforced material, selecting a number of tows to utilize for a bundle having an aggregate shape, assembling the tows together into the bundle, curving the assembled tows by slipping the assembled tows with respect to each other, drawing the bundle through a die to bind the bundle into a preform, enforcing a longitudinally varying cross section along the preform, and locking in a curvature of the preform.

A pultrusion method, equipment for preparing a fiber-reinforced composite, and a fiber-reinforcement composite are provided. The pultrusion method comprises the following steps: i) preforming inner layer fibers; ii) impregnating the preformed inner layer fibers with a first resin to obtain a first preform; iii) heating and curing the first preform to obtain an inner layer profile; iv) preforming outer layer fibers together with the inner layer profile; v) impregnating the outer layer fibers with a second resin to obtain a second preform; and vi) heating and curing the second preform to obtain the fiber-reinforced composite.

Method of manufacturing a structural member includes moving fibers (130) along an assembly line (100), applying binder to spaced apart fibers (130) extending across a first area, and applying a traction agent (178) to at least one of the fibers and the binder. A tapered die (180) has a first portion (195) with a first greater diameter positioned to receive the fibers and a second portion with a second lesser diameter positioned downstream of the first portion. Guiding the fibers along the die and decreasing a distance between the plurality of fibers with the die. After decreasing the distance between the plurality of fibers, the fibers extend across a second area that is smaller than the first area, and the plurality of fibers are shaped with a shaping station. Traction agent increases friction between at least one of the fibers and either an adjacent fiber or the die during shaping.