A joining method for connecting at least two thermoplastic workpieces is provided to permit the joining even of non-transparent carbon fiber reinforced plastics parts by means of laser welding, in which a splice is produced at the edge regions of the workpieces and the workpieces are subsequently positioned relative to one another in such a manner that the opposite splice regions bound a seam region. Connecting bodies are then inserted into the seam region and heated by means of local heat input by laser beam such that a fixed integrally bonded connection forms between the workpieces and the connecting bodies.

A heating element for resistance welding of thermoplastic components includes an electrically conductive sheet with cut-outs, wherein a ratio of cut-outs to electrically conductive sheet changes at least along a transverse direction of the sheet, so that an electrical resistance of the sheet has a maximum at a center of the sheet. A welding kit includes the heating element and an electrical insulation layer. A method of manufacturing the heating element, and a method of employing the heating element for welding two thermoplastic components to one another are disclosed.

A thermoplastic welding assembly includes a structural cage that supports a press and one or more hydraulic and pneumatic actuators. The press includes first and second plates that movable toward and away from each other to load and remove thermoplastic components to be held together for thermoplastic welding. Specifically, the first plate of the press includes non-conductive tooling inserts that are positioned to form a slot for a welding prove, and the second plates includes non-conductive tooling inserts that form cavities for plungers to move through. Plungers that are movable using the actuators are positioned in the cavities of the second plate, and compressible pressurizers are attached to the ends of the plungers. An operator uses electrical controls to move the plungers in the plunger cavities toward the thermoplastic components in the press to drive the pressurizers into the thermoplastic components and provide stabilizing pressure on the components during welding.

A method including receiving a model of a composite structure having an inconsistency. The model includes a pre-calculated heating model that specifies areas of the inconsistency for which corresponding different amounts of heating are applied to an uncured composite material that is applied to the inconsistency. A design for heating elements of varying density across the areas is generated from the model. The design is configured to cause the heating elements in a first sub-area of a heat blanket system to generate a first amount of heat in a third area in the areas, and to cause the heating elements in a second sub-area of the heat blanket system to generate a second, different amount of heat in a fourth area of the areas. The heating elements are printed according to the design on a blanket to manufacture the heat blanket system.

A method and apparatus for tacking and trimming a thermoplastic tow. A thermoplastic tow is received from a braiding system over a braided structure on a surface. The thermoplastic tow is tack welded to the braided structure. A portion of the thermoplastic tow is trimmed to thereby trim the thermoplastic tow received over the braided structure.

A method for manufacturing a composite barrel structure includes fabricating a first plurality of composite panels that are assemblable into a first partial composite barrel section. The fabricating includes assembling a first layup of composite material and, concurrently, assembling at least one additional layup. The fabricating further includes heating the first layup with the at least one additional layup. A system for fabricating a plurality of panels that are assemblable into partial barrel sections includes a first workstation for fabricating a first plurality of composite panels that are assemblable into a first partial composite barrel section. The first workstation includes a first assembly station configured to concurrently assemble a first layup of composite material and at least one additional layup and a first heating station configured to heat the first layup concurrently with the at least one additional layup to yield the first plurality of composite panels.

Aircraft stringers having carbon fiber reinforced plastic (CFRP) material reinforced flanges are disclosed. An example stringer to be coupled to a skin of an aircraft comprises a flange. The flange includes a first portion of a first stiffening segment. The flange further includes a first portion of a second stiffening segment coupled to the first portion of the first stiffening segment. The flange further includes a CFRP reinforcement segment coupled to the first portion of the first stiffening segment and to the first portion of the second stiffening segment. The CFRP reinforcement segment strengthens the first portion of the first stiffening segment and the first portion of the second stiffening segment.

A heat blanket system including a blanket including a first sub-area and a second sub-area. The heat blanket system also includes heating elements printed on the blanket. First spacings between first ones of the heating elements in the first sub-area varies relative to second spacings between second ones of the heating elements in the second sub-area. The first spacings and the second spacings vary according to a design. The design is configured for use on a uniquely defined rework area on a uniquely defined composite material object including a third area including a heat sink region and a fourth area including a non-heat sink region. The first sub-area is sized and dimensioned to be placed over the third area. The second sub-area is sized and dimensioned to be placed over the fourth area.

A core according to one aspect of the present disclosure is a core that is inserted into a space between a skin and a stringer in a step of integrally molding the skin and the stringer, the skin including fiber-reinforced resin, the stringer having a hat-shaped section that is open toward the skin. The core includes: a first die that extends along a longitudinal direction of the stringer and contacts the skin; a second die that extends along the longitudinal direction of the stringer, is adjacent to the first die, and contacts the skin; and a third die that extends along the longitudinal direction of the stringer, is located at an opposite side of the skin across the first die and the second die, and contacts both the first die and the second die.

Systems and methods for 3D printing hollow bodies, such as bodies having an exterior cylindrical shape with a hollow interior, are described. Such systems and methods utilize rotatable hollow print base supports having an interior size and/or shape that matches the desired exterior shape of the final printed structure. The printed bodies, methods, and systems enable printing of the desired hollow printed body from the outside-to-inside. They also allow easy production, customization, and modification of internal structures within the printed hollow body.