According to an aspect, a method of assembling a mandrel includes assembling a plurality of members via interlocking features arranged at opposing edges of each member of the plurality of members to form a compartment, the assembled members having a collective outer surface that conforms to an inner surface of the spar. A support member is inserted into the compartment formed radially inward from the assembled members, the support member making contact with a portion of each member of the plurality of members.

A system for constructing a composite structure includes a braiding machine, a winding tool and a forming machine. The composite structure is constructed of a wound tubular braiding. The wound tubular braiding is constructed of a biaxial or triaxial tubular braid of unidirectional tape.

This invention relates to a pressure vessel comprising a hollow body comprising endless fibers embedded in a thermoplastic polymer, in which the thermoplastic polymer comprises one or more polyamides containing one or more aliphatic monomeric units, wherein the one or more polyamides have a CH2-ratio of at least 5.5 and less than 10, calculated by □ identifying the number of different aliphatic monomeric units in the one or more polyamides; □ determining the number of CH2 groups per aliphatic monomeric unit for each of these different aliphatic monomeric units; □ calculating the sum of the so determined numbers of CH2 groups; □ dividing said sum by the number of different aliphatic monomeric units in the one or more polyamides; taking into account only the aliphatic monomeric units present in the one or more polyamides in an amount of at least 10 wt % with respect to the total weight of the one or more polyamides.

A tool for forming a composite structure may include two or more segments formed from a polymer material. The tool may further include a crush insert disposed between the two or more segments. The tool may also include a support shaft coupled between the two or more segments. A method of forming a mandrel may include forming segments of the mandrel through an additive manufacturing process. The method may further include assembling the segments relative to one another. The method may also include positioning a crush insert between each of the segments. A method of fabricating a composite structure is also disclosed.

A mandrel for a molding process that includes a first portion that has a first portion outer surface, a first portion inner surface, a first portion first end, and a first portion second end. A thickness of the first portion first end is greater than the first portion second end. A second portion has a second portion outer surface, a second portion inner surface, a second portion first end, and a second portion second end. A thickness of the second portion first end is smaller than the second portion second end. The first portion inner surface engages the second portion inner surface to form a mandrel that has a constant cross-section.

The present invention describes a method for producing a leak-tight vessel for holding a gas and/or liquid, comprising the steps of winding a heat-sealable thermoplastic barrier strip around a removable mandrel in such a way that each strip fragment overlaps with a substantially parallel strip fragment over at least a lateral overlapping distance, consolidating the overlapping strip fragments so as to form a gas and/or liquid tight layer, winding a fibrous material around the gas and/or liquid tight layer, thereby leaving an opening large enough for removing the mandrel. The invention also describes a leak-tight vessel produced in this way.

A core system for the production of a fiber composite component includes at least two core elements which are coupled to one another and are displaceable relative to one another. At least one core element has a surface which is oblique to a displacement direction. A method for producing the fiber composite component uses the core system.

The invention relates to a tape, comprising at least one layer comprising a. endless fiber in an total amount of at least 40 volume % as compared to the total volume of the layer and b. a thermoplastic matrix comprising one or more polyamides containing one or more aliphatic monomeric units, c. and optionally heat stabilizer, flame retardant, colorant, lubricant, mold release agent, UV stabilizer, impact modifier, laser absorbing additive as well as combinations thereof; wherein the one or more polyamides have a CH2-ratio of at least 5.5 and less than 10, calculated by—identifying the number of different aliphatic monomeric units in the one or more polyamides; —determining the number of CH2 groups per aliphatic monomeric unit for each of these different aliphatic monomeric units; —calculating the sum of the so determined numbers of CH2 groups; —dividing said sum by the number of different aliphatic monomeric units in the one or more polyamides; taking into account only the aliphatic monomeric units present in the one or more polyamides in an amount of at least 10 wt % with respect to the total weight of the one or more polyamides. The invention also relates to a vessel prepared by employing these tapes.

A method of constructing a mandrel generally complementary to a spar cavity of a spar includes connecting a first component and a second component to form a central space there between and inserting a center component within the central space such that the center component retains the first component and second component in a desired position forming an outer surface of the mandrel which corresponds to an inner surface of the spar cavity.

Methods and apparatuses for electromagnetic support tooling for use in composite part curing are described. In one example, a support tooling, such as a mandrel, includes an elastomeric housing that has ferromagnetic components. The mandrel also has electro-magnetic coils positioned within the elastomeric housing and operable to generate magnetic fields to repel or attract the ferromagnetic components of the elastomeric housing to the electro-magnetic coils. When the ferromagnetic components of the elastomeric housing are repelled by the electro-magnetic coils, the elastomeric housing has a rigid surface state. When the ferromagnetic components of the elastomeric housing are attracted to the electro-magnetic coils, the elastomeric housing is collapsed.