Abstract: Method for manufacturing stiffened panels comprising the following steps: forming a first and a second wet skin, each comprising a plurality of plies of preimpregnated composite material; forming a plurality of pairs of wet stringers, comprising a plurality of plies of preimpregnated material, wherein forming each pair of wet stringers comprises a) forming an assembly having a central web extending between opposite end flanges, and b) cutting the assembly along a median plane so as to form a pair of wet stringers, placing the pairs of wet stringers on the first wet skin by means of removable supporting members; turning the second wet skin over and placing it on the pairs of stringers, so as to obtain a pair of wet panels arranged above each other; and subjecting the pair of wet panels to a same curing cycle.

Abstract: Method for manufacturing stiffened panels, comprising the following steps: forming a first and a second wet skin, each comprising a plurality of plies of preimpregnated composite material; forming a plurality of pairs of wet stringers, comprising a plurality of plies of preimpregnated material, wherein forming each pair of wet stringers comprises a) forming an assembly having a central web extending between opposite end flanges, and b) cutting the assembly along a median plane so as to form a pair of wet stringers, placing the pairs of wet stringers on the first wet skin by means of removable supporting members; turning the second wet skin over and placing it on the pairs of stringers, so as to obtain a pair of wet panels arranged above each other; and subjecting the pair of wet panels to a same curing cycle.

Abstract: A tool for forming a C-section beam made of carbon fiber includes a straight elongated mandrel with a rectangular or trapezoidal cross-section. The mandrel has three consecutive outer faces, with a planar face configured to form a surface of the web of the C-section beam, and two opposing lateral faces, configured to form two respective surfaces of the flanges of the C-section beam. The mandrel has a distributed perforation on at least one of the three outer faces and an inlet/outlet connection to connect the mandrel to an external source of vacuum and/or compressed air. Passages are formed inside the mandrel to establish a fluid communication between the distributed perforation and the inlet/outlet connection. Through the distributed perforation, a vacuum is applied to the interface between the mandrel and the C-section beam to retain the C-section beam on the mandrel while lifted and turned by 180° for coupling to a similar C-section beam to assemble an H-beam.

Abstract: A tool for forming a C-section beam made of carbon fibre includes a straight elongated mandrel with a rectangular or trapezoidal cross-section. The mandrel has three consecutive outer faces, with a planar face configured to form a surface of the web of the C-section beam, and two opposing lateral faces, configured to form two respective surfaces of the flanges of the C-section beam. The mandrel has a distributed perforation on at least one of the three outer faces and an inlet/outlet connection to connect the mandrel to an external source of vacuum and/or compressed air. Passages are formed inside the mandrel to establish a fluid communication between the distributed perforation and the inlet/outlet connection. Through the distributed perforation, a vacuum is applied to the interface between the mandrel and the C-section beam to retain the C-section beam on the mandrel while lifted and turned by 180° for coupling to a similar C-section beam to assemble an H-beam.

Abstract: For the manufacturing of a beam of composite material based on carbon fibre, a support plane is overlain with a plurality of mats of carbon fibre pre-impregnated with resin so as to obtain at least one flat laminate. Then at least one edge of the flat laminate is cut at a pre-determined cut angle different from 90° with respect to the support plane. Then the flat laminate is placed on a shaping tool. Then the laminate is hot shaped so as to copy the shape of the shaping tool bending at least one part of the laminate delimited by the cut edge in such a way that the cut edge defines, at the end of the bending phase, a surface orientated perpendicularly with respect to the bent part. Finally temperature and pressure is applied in such a way as to polymerise the resin contained in the layers of matting.