A dental preform comprises a central portion formed by a plurality of first wire-like elements extending mostly in a first direction, and a first resin. An annular peripheral portion passes round the central portion perpendicularly to the first direction. The peripheral portion comprises second wire-like elements and a second resin. The peripheral portion comprises a plurality of layers arranged on one another perpendicularly to the first direction. Each layer has at least one turn formed by at least one of the second wire-like elements, the at least one second wire-like element presenting a longitudinal direction that is offset with respect to the first direction by an angle comprised between 10° and 80° or between 100° and 170°. The second wire-like elements of two consecutive layers present opposite orientations.

A dental preform comprises a central portion formed by a plurality of first wire-like elements extending mostly in a first direction, and a first resin. An annular peripheral portion passes round the central portion perpendicularly to the first direction. The peripheral portion comprises second wire-like elements and a second resin. The peripheral portion comprises a plurality of layers arranged on one another perpendicularly to the first direction. Each layer has at least one turn formed by at least one of the second wire-like elements, the at least one second wire-like element presenting a longitudinal direction that is offset with respect to the first direction by an angle comprised between 10° and 80° or between 100° and 170°. The second wire-like elements of two consecutive layers present opposite orientations.

The invention relates to a method for producing a hollow electrical insulator having the following steps:—providing a core,—winding first wound layers (2) of a first fiber element onto the core,—winding second wound layers (7) of a second fiber element (8) onto an end region (10) of the core, wherein—the first wound layers (2) comprise turns of the first fiber element which include a first winding angle with a main direction of extension (R) of the core,—the second wound layers (7) comprise turns (18) of the second fiber element (8) which include a second winding angle (α2) with the main direction of extension (R) of the core, which second winding angle is larger than the first winding angle, and—an inner region (11) of the core remains free of second wound layers (7). The invention also relates to a hollow electrical insulator and the use thereof.

A filament winding method and system without needing a resin dip bath are disclosed. The method comprises feeding a fiber band of a plurality of fibers onto a mandrel without dipping the fibers in a resin bath, and applying a resin onto the fiber band at or about where the fiber band contacts the mandrel or applied directly to the fiber band and then wound onto the mandrel so that the resin is between the mandrel and the fiber band at the point of contact. In some embodiments, the resin can be sprayed onto the fibers and in other embodiments, the resin can be delivered in at least one layer onto the fiber band that is then impregnated into the fiber band as the fiber band wraps around the mandrel. The fiber can comprise carbon fiber, basalt fiber, glass fibers, Kevlar fiber, polyester fiber, other fibers, or a combination thereof.

A filament winding method and system without needing a resin dip bath are disclosed. The method comprises feeding a fiber band of a plurality of fibers onto a mandrel without dipping the fibers in a resin bath, and applying a resin onto the fiber band at or about where the fiber band contacts the mandrel or applied directly to the fiber band and then wound onto the mandrel so that the resin is between the mandrel and the fiber band at the point of contact. In some embodiments, the resin can be sprayed onto the fibers and in other embodiments, the resin can be delivered in at least one layer onto the fiber band that is then impregnated into the fiber band as the fiber band wraps around the mandrel. The fiber can comprise carbon fiber, basalt fiber, glass fibers, Kevlar fiber, polyester fiber, other fibers, or a combination thereof.

Medical constructs with collagen fibers and gelatin and related collagen fibers. The collagen fibers can be derived from extruded soluble dermal collagen and can include a gelatin film attached to the at least one collagen fiber. The gelatin film can include one or more minerals and has a gelatin concentration of between about 0.1% to about 40% weight per volume.

A method for producing a high-pressure tank capable of winding a reinforcing fiber bundle around a liner without deteriorating tank performance. The method for producing a high-pressure tank by winding a resin-impregnated strip-shaped reinforcing fiber bundle around a rotating liner so as to form a fiber-reinforced resin layer on the outer surface of the liner includes while winding the strip-shaped reinforcing fiber bundle around the liner, concurrently winding another bundle of fibers narrower than the strip-shaped reinforcing fiber bundle around the liner so as to cross the strip-shaped reinforcing fiber bundle.

A winding method and apparatus for producing a consolidated metal matrix composite is described. The methods are directed to winding softened metal matrix composite tape and layering the resulting softened metal matrix composite tape onto a rotating mandrel in a prescribed pattern on the surface of the mandrel to form a consolidated metal matrix composite. Upon cooling, the matrix metal solidifies and the resulting consolidated metal matrix composite may be removed from the mandrel. The consolidated metal matrix composites may be produced in a variety of shapes, such as cylinder, a tapered cylinder, a sphere, an ovoid, a cube, a rectangular solid, a polygonal solid, and panels.

A high-pressure tank includes a cylindrical portion including a fiber-reinforced resin and a dome portion including a fiber-reinforced resin. The cylindrical portion includes an axial fiber layer including a fiber oriented in a center axis direction of the high-pressure tank, and a circumferential fiber layer including a fiber oriented in a circumferential direction of the high-pressure tank. An end portion of the axial fiber layer and an end portion of the dome portion are joined to each other.

Disclosed are reinforced structures. The structures are comprised of reinforced elements that have continuous fibers embedded in a matrix material. The reinforced elements are combined in a matrix material to form a desired shape of reinforced structure.