Читать диплом по транспорту, грузоперевозкам: "Improving the process of repair of the aircraft panels made of composite materials" Страница 3

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the number of ribs.with layered plating may be easier with a single-layer lining the wing, supported by stringers. The surface quality of the laminated roof sheathing due to the lack of riveted joints get higher. Laminated paneling has good insulating properties that makes it profitable for its application subject to large aerodynamic heating wings of supersonic aircraft, interior volumes are busy fuel.laminated paneling and has major drawbacks. The technology of producing a laminated sheathing complicated complex quality control gluing or soldering carrier layers to a placeholder, difficult repair skin. Great difficulties encountered in the implementation of the joint parts layered skin and its interface with the elements of the power set of wings.the junction is necessary to make a connection not only heavily loaded bearing layers of skin, but also padding that ensures their work together. Joint sheathing panels produced at special border. Edging glued or soldered to the supporting skin layers and to a placeholder. The panels, performed using anchor screws, nuts or bolts.cladding elements with power set wing also produced using fringing. In order to reduce the weight of the layered skin should strive to reduce the number of joints. If the process of the design considerations and can produce long sheathing panel exceeding the length of sheets extending on its carrier layer, the first connecting lining carrier layers using soldering or gluing, and then combine them with a filler.the wings of the modern monoblock speed aircraft is widely used siding monolithic panels. This wing almost all senses load weight and trim it constitutes the main part of the mass of the wing. Application of monolithic cladding reduces the weight of the wing due to compliance with the applicable sections sized loads and significantly lower than in the panels with metal cover, the number of connections.made of monolithic panels have increased torsional rigidity, which is favorable from the viewpoint of aeroelasticity. However, monolithic panels in comparison with the teams have some drawbacks: the complexity of manufacturing large, significant material waste, high cost, difficulty of repair, the worst characteristics of fatigue strength. Monolithic panels produced by milling of plates, compression; rolling, forging and casting. Plates, which are made of milled panel, obtained by hot rolling or forging.configuration panel is milled in special key-cutting machine tools and machining centers. Panel for more than a simple configuration and can be produced by chemical milling. Curved panels are obtained by milling or flat panel followed by flexible plate or imparting the necessary curvature of the free forging followed by milling to the desired contour.produced panel of constant cross section parallel longitudinal set. After heat treatment panel is machined molding and final finishing by circumscription. May be prepared by rolling and panels wafer. Before rolling the billet, and the matrix is heated to a hot forging temperature.processing is performed in the panel the same as the processing of the pressed panel. When hot press forming longitudinal and transverse panels and the set thickness of the panel may have a variable cross section along the length, cross sectional shape of trapezoid ribs. Since stamping not possible to get the required dimensional accuracy of the ribs and planking thickness must be calibrated panels or additional machining.panels casting allows you to design with a complex set of power and with a shell thickness significantly less than with other methods for producing panels. Panels made by casting, require less machining. Each of the methods of manufacturing the panels has its own advantages and disadvantages.of panels made from milled plates are getting complex configuration panels with variable cross-sections, the relatively high accuracy and surface relative simplicity and low cost used equipment; The disadvantages include a large waste of material (up to-90%). High labor intensity and the worst compared with stamped panels mechanical properties. Advantages pressed panels are their high mechanical properties, low material waste and lower compared to forging power equipment.disadvantage is the limited shapes and sizes of panels. The advantages of the panels produced by rolling, it is necessary to take possibility of obtaining much smaller than the molded panels, the thickness of the panel (1 mm or even less), as compared with a hot stamped panels - lower capacity equipment and the comparative simplicity, and hence less tooling costs. A drawback is the limited hot rolled panels geometric shapes in comparison with stamped panels.stamped panels have almost the same high strength as chipboard panels. When you clone panels provided the desired change in cross-sectional area of ribs and planking thickness obtained low material waste. The major drawback of this method of manufacturing the panels is a lot of power equipment., for the manufacture of panels of aluminum alloy requires a force of 300,000 N per square meter. Therefore, the size limited stamped panels. Most labor and die manufacturing cycle and the inability to obtain the required dimensional accuracy ribs and planking thickness without additional processing are also disadvantages to this method of manufacturing the panels.of manufacturing panels cast consist in the possibility of producing large-size panels required, power set, thin skin and necessary in terms of strength change in cross-sectional areas along the length. The advantages of this method of manufacturing the panels should also include low material waste, much greater productivity and low complexity of manufacturing equipment. The main drawback of cast panels - the worst mechanical characteristics.have proliferated panel made of composite materials. Composite cladding began to use coal - and boroplastics. Panel of composite material allow to obtain high strength and rigid