Abstract: A load-bearing tubular structural shell for use particularly in aerospace applications includes a structural frame of lattice-like structure formed by intersecting helical, girth, and longitudinal stiffening ribs, ad an outer covering surrounding the structural frame. The ribs are formed by helical, girth, and longitudinal strips of unbidirectional fibers wrapped in intersecting and overlapping fashion to form a plurality of layers of the strips. The longitudinal and girth ribs intersect at nodes, and at least some of these nodes are attached to helical ribs so as to form closed structural triangular nodes. Two sides of each triangular node are formed by first faces of the longitudinal and girth ribs, and the opposite second faces of the longitudinal and girth ribs intersect at a corner that lies within the closed triangular node. The helical rib at the triangular node has one face that lies within the closed triangular node and an opposite face that forms a third side of the triangular node.

Abstract: The invention relates to machine-building. More specifically, it pertains to shell fabrication of airframe parts, which are used in aerospace equipment operating under compound stress. The invention also covers methods and apparatus for the fabrication of the shell structures.The invention aims to improve wall rigidity and strength.A tubular pressure vessel in the form of a composite cylindrical body incorporates a lattice-type frame 1 and external protective cover 2; the grid frame is made by winding a layered system 3 of helical 4, longitudinal 5, girth 6, and oblique transition strips 14 linking the girth strips 6; the pattern forms interleaved stiffening ribs 8, 9, 10, 15. The winding is applied to the mandrel, the core 17 is covered with thermostabilized flexible plates 19 with a web of grooves 23, 24, 25, 26 for imbedding a matching pattern of strips 6,4,5, and 14.

Abstract: The inventions relate to the field of machine manufacturing and more specifically, to shell-type construction of base members used in aviation engineering and rocketry, which operate under conditions of combined stressed state, to the methods of and mandrels for their manufacture.A load-carrying tube-shell comprises a cellular framework 1 made of spiral and annular strips 4, 5 crossing each other to define layers 3 of systems repeated over the thickness of the wall thereof so that stiffening ribs 6, 7 with criss-crosses 8, 9, 10 are thus formed, and outer coating layers 2 respectively made of unidirectional filaments 11 bound by a cured polymeric binder 12. Damping-absorbing layers 14 of resilient-elastic material such as rubber or polyurethane are disposed between the layers 3.A method of the manufacture of the tube-shell comprises a step of introducing intermediate continuous forming strips 20 placed beneath the layers 4, 5 laid down under tension.