Methods and structures are disclosed. An example method includes: rotating a tubular mandrel about a longitudinal axis of the tubular mandrel; depositing a composite material on an inner surface of the tubular mandrel to form a composite tubular member on the inner surface of the tubular mandrel; inserting and expanding an inner expandable mandrel within the composite tubular member to cause the inner expandable mandrel to press the composite tubular member against the inner surface of the tubular mandrel; curing the composite tubular member; removing the inner expandable mandrel; placing a frame within the composite tubular member; and removing the tubular mandrel so as to obtain the composite tubular member with the frame placed therein.

A carrier film set configured to apply a number of stiffener assemblies to a layup mandrel, the carrier film set comprising: a number of alignment features configured to align the carrier film set relative to the layup mandrel; and a number of indexing features configured to index the number of stiffener assemblies onto the carrier film set.

A carrier film set configured to apply a number of stiffener assemblies to a layup mandrel, the carrier film set comprising: a number of alignment features configured to align the carrier film set relative to the layup mandrel; and a number of indexing features configured to index the number of stiffener assemblies onto the carrier film set.

In a filament winding apparatus, a supplying device supplies fiber bundles to a surface of a core material. A moving part is movable relative to the core material, and rotatable around a rotational axis extending in a vertical direction. A small diameter aligning guide part is placed at the moving part and has an opening portion through which the core material can pass. The small diameter aligning guide part guides fiber bundles to an outer peripheral surface of the core material such that the fiber bundles are arranged side by side in a circumferential direction of the core material. The tightening fiber bobbin supporting part is placed at the moving part and rotates around a center of the opening portion. A winding guide rotates with the tightening fiber bobbin supporting part and guides a tightening fiber bundle drawn from a tightening fiber bobbin toward the surface of the core material.

In a filament winding apparatus, a supplying device supplies fiber bundles to a surface of a core material. A moving part is movable relative to the core material, and rotatable around a rotational axis extending in a vertical direction. A small diameter aligning guide part is placed at the moving part and has an opening portion through which the core material can pass. The small diameter aligning guide part guides fiber bundles to an outer peripheral surface of the core material such that the fiber bundles are arranged side by side in a circumferential direction of the core material. The tightening fiber bobbin supporting part is placed at the moving part and rotates around a center of the opening portion. A winding guide rotates with the tightening fiber bobbin supporting part and guides a tightening fiber bundle drawn from a tightening fiber bobbin toward the surface of the core material.

A method of manufacturing a high-pressure tank includes: forming a vessel body including a body portion having a cylindrical shape, a domical portion having a hemispherical shape and provided at an end of the body portion, and a neck portion extending from the domical portion in an axial direction of the domical portion; winding fibers around an outer peripheral surface of the vessel body to form a plurality of fiber layers laminated in a radial direction of the vessel body; and placing, in a mold, the vessel body around which the fibers have been wound, and then injecting a resin onto the neck portion in an axial direction of the vessel body to impregnate the fibers with the resin.

A method for manufacturing a high-pressure tank including a liner and a reinforcing layer covering an outer surface of the liner includes: forming a cylinder member made of a fiber-reinforced resin; forming a pair of dome members made of the fiber-reinforced resin; and forming a reinforcing body that is the reinforcing layer by joining the cylinder member and the dome members. When forming the cylinder member, a resin-impregnated fiber sheet is wound around an outer peripheral surface of a mandrel to form a cylinder body, and a resin-impregnated fiber bundle is then wound so as to overlap the cylinder body.

Aspects of the present disclosure include a pickleball paddle that is formed using a plastic or composite molded material. A composite material is wrapped around a center and placed in a mold to form a paddle frame or arranged around a paddle frame. In some embodiments, additional composite material is wrapped at specific positions to tune the balance point and rebound characteristics of the finished paddle The mold is heated to cure the composite material within the mold cavity. Face shells are then added to complete the paddle.

Systems and methods are provided for forming a laminate. The method includes indexing a layup mandrel to a lamination machine disposed at a first location, transporting the lamination machine and the layup mandrel in a process direction from the first location towards a second location, laying up a laminate comprising layers of fiber-reinforced material onto the layup mandrel via the lamination machine while the lamination machine and the layup mandrel are transported in the process direction, removing the layup mandrel and the laminate at the second location, and returning the lamination machine to the first location for laying up another laminate onto another mandrel.

Systems and methods are provided for forming a laminate. The method includes indexing a layup mandrel to a lamination machine disposed at a first location, transporting the lamination machine and the layup mandrel in a process direction from the first location towards a second location, laying up a laminate comprising layers of fiber-reinforced material onto the layup mandrel via the lamination machine while the lamination machine and the layup mandrel are transported in the process direction, removing the layup mandrel and the laminate at the second location, and returning the lamination machine to the first location for laying up another laminate onto another mandrel.