A method for renovating the interior of a hollow structure such as a sewerage pit (1) is described. The method provides an access opening (16) to the hollow structure (1); provides a plurality of material sheets (3) comprising reinforcing fibers and a curable resin composition through the access opening (16) and against a wall (11a, 11b) of the hollow structure (1); and provides an inflatable pressure means (4a, 4b) within the hollow structure (1). The pressure means (4a, 4b) are inflated against the wall (11a, 11b). A curing means (6) is then provided within the hollow structure (1) for curing the resin composition; and the resin composition is cured to harden the material sheets and provide a renovated interior of the hollow structure (1).

A method of fabricating a composite structure includes laying at least one composite ply about a bladder, the bladder comprising a phase change material in a first phase having a first volume, positioning an outer mold about the bladder and the at least one composite ply, and curing the at least one composite ply to form the composite structure. Curing causes the phase change material contained within the bladder to change to a second phase to expand from the first volume to a second volume and apply a pressure to an interior surface of the composite ply and press an outer surface of the composite ply against the outer mold to form an interior cavity. The bladder is not removable from the formed interior cavity.

A method for manufacturing a wind turbine blade, includes the steps of: arranging an upper mould including a pre-casted fibre lay-up on a lower mould comprising a dry fibre lay-up and a mould core, applying vacuum to a space between the upper and lower moulds and the mould core, infusing at least the dry fibre lay-up and a connection region between the dry fibre lay-up and the pre-casted fibre lay-up with a resin, and curing the resin.

By having the pre-casted fibre lay-up in the upper mould, the packing and positioning of dry composite materials on top of the mould core is avoided.

A method for making a composite part using a reformable mandrel, including contouring a reformable mandrel; placing an uncured composite part on the reformable mandrel; curing the uncured composite part; and removing the reformable mandrel, wherein the reformable mandrel includes a core including a transitional state material having a transition temperature, and a sleeve at least partially surrounding the core and including a heat-resistant flexible material having an operational temperature.

A tool for forming a part includes a first tool portion including a first tool surface. The tool further includes a second tool portion comprising a second tool surface facing the first tool surface, wherein the first tool surface and the second tool surface define a tool chamber for forming the part. The tool further includes a bladder subassembly disposed in the tool chamber between the first tool surface and the second tool surface. The bladder subassembly includes a plurality of inner bladders disposed within tool chamber, wherein each inner bladder of the plurality of inner bladders includes an inner bladder chamber that is independently inflatable to selectively apply pressure to the part. The bladder subassembly further includes a bladder cover disposed over the plurality of inner bladders within the tool chamber to provide a barrier between the plurality of inner bladders and the part.

According to one implementation, a composite material molding jig 3 includes a tubular member 5 and at least one rigid plate member 6 (6A, 6B) so that a composite material structure O (O1, O2) having a hollow structure can be formed easily. The tubular member 5 has flexibility. The at least one rigid plate member 6 (6A, 6B) reinforces strength of the tubular member 5 partially. The tube is used in a state where air is introduced inside the tube. Further, according to one implementation, a composite material molding method includes using the above-mentioned composite material molding jig 3 in order to produce a composite material structure O (O1, O2) so that the composite material structure O (O1, O2) having a hollow structure can be formed easily.

A method of manufacturing a high-pressure composite pressure vessel for high-pressure being at or above 70 bar (1000 PSI or 7 MPa) includes providing an expandable core vessel defining a hoop section between end domes. An aligned discontinuous fiber composite material is wrapped over the expandable core vessel aligning with a plurality of load paths present in the expandable core vessel being over the hoop section and end domes. The aligned discontinuous fiber composite material has fibers in a prepreg tape that are at least 5 mm in length to 100 mm in length or less. Next, a continuous fiber-reinforced composite is wrapped over the aligned discontinuous fiber-reinforced composite along the hoop section and not wrapped along the end domes. The expandable core vessel may be pressurized and heated to consolidate the composite overwrap. Finally, the vessel is cooled under pressure resulting in the high-pressure composite pressure vessel.

A system includes a U-shaped chute, one or more feeder mechanisms, a sock application assembly, and a film application assembly. The chute has a chute inlet and a chute outlet and is configured to receive a mandrel having a mandrel length. The one or more feeder mechanisms are configured to move the mandrel into the chute inlet and through the chute. The sock application assembly has a sock material spool containing a breather sock in tubular form. The sock application assembly is configured to progressively apply the breather sock over the mandrel length as the mandrel exits the chute outlet. The film application assembly has a film material spool containing a film in tubular form. The film application assembly is configured to progressively apply the film over the breather sock covering the mandrel exiting the sock application assembly to thereby form a film-sock-mandrel assembly.

A bonding tool is described that is used to secure sacrificial pads to bonding locations on a perimeter of a rib during a bonding process. In one embodiment, the bonding tool includes a base member having a rib receptacle dimensioned to receive a rib of a wing, a plurality of compression forms disposed around at least a portion of the rib receptacle and proximate to a perimeter of the rib, where the compression forms include a plurality of sacrificial pads that face towards bonding locations on the perimeter of the rib, and at least one bladder proximate to the compression forms that expands between a wall of the base member and the compression forms to press the sacrificial pads against the bonding locations while the sacrificial pads bond to the bonding locations.

A device and a process for manufacturing a composite part, the device comprising four molding mandrels that can be arranged in a mold arrangement in which they form a mold for the composite part, as well as a locking mandrel configured to lock the molding mandrels in the mold arrangement and to be extracted from between the molding mandrels to release the molding mandrels from their mold arrangement. The locking mandrel extends from one longitudinal end of the molding mandrels to another opposite longitudinal end of the molding mandrels.