A process for preconsolidating a planar porous fiber-thermoplastic resin layer which is unconstrained in the in-plane directions by heating the layer to above the melting point of the resin, then applying pressure to the plane of the layer causing resin flow, thus orienting the fibers in the plane of the layer.
There would be less waste of material, and thus less expense to the customer, if the composite material could be furnished in continuous roll form, i.e., like a bolt of cloth, rather than in squares or rectangles. 4,403,012, 4,457,985 and 4,916,000, all of which are hereby incorporated by reference. This patent is exemplary of the prior art represented by the SPECTRA SHIELD material discussed above. The present invention provides a method and apparatus for the continuous, automated cross-plying of material, preferably for anti-ballistic end use or in impact resistant structural components, e.g., radomes, sonar domes, helmets.
This would permit the customer to maximize material usage by continuously repeating the pattern to be cut from the continuous length of material and thereby eliminate the scrap formed by using rectangular sheets. In one embodiment, the apparatus is for the automated cross-plying of a first, continuous ply of material and a plurality of second, discontinuous plies of material into a cross-plied continuous length of material, each of the first and the second plies of material having a longitudinal axis.
The preferred first supply means comprises a roll on which the first ply of material and the first carrier web are wound together, and the preferred first pull means comprises a pair of driven pinch rolls downstream of the cross-plying zone.
Alternatively, the first supply means comprises a driven feed roll on which the first ply of material and the first carrier web have been wound together, and the first pull means comprises a driven roll downstream of the cross-plying zone.
SPECTRA SHIELD material can be incorporated into lightweight body armor or rigid composite armor, with the threat level determining the number of layers of material used. The patent teaches that the prepreg sheets can be plied together, with successive sheets being rotated relative to the first sheet, to form simple composite materials. The plies are resin impregnated fiber plies which are brought into longitudinal alignment, combined and laminated.
The material is typically delivered to the customer in rectangular, preferably square, sheets which can then be cut and fabricated into a desired configuration. These composite materials are of a given size, e.g., 12×12 inches (4.7×4.7 cm), and are individually molded prior to being sent to the customer. The present invention, which was developed in an attempt to overcome the deficiencies of the prior art, provides a cross-plied material by a continuous, automated method.It is preferred that the discontinuous plies releasably adhere to the second carrier web.The preferred second pull means is a pair of driven pinch rolls.Reticular framing and shotcrete with steel fibres as a means of support after the excavation.There is described a process for producing a cover for a side airbag, which comprises first producing a polyester web, preconsolidating this web by needling and end-consolidating and fully shrinking the thus preconsolidated web by means of an embossing calender, making the thus consolidated and fully shrunk web up into a cover and providing the cover with a predetermined breaking site to tear open the cover in the event of a collision. A process for producing a cover for a side airbag, which comprises first producing a polyester web, preconsolidating this web by needling and end-consolidating and fully shrinking the thus preconsolidated web by means of an embossing calender, making the thus) consolidated and fully shrunk web up into a cover and providing the cover with a predetermined breaking site to tear open the cover in the event of a collision.Construction of a 60m long approach cutting and a tunnel and passage with a length of 210m in loose material composed mainly of gravel and silt.