Double-curvature rectangular reinforcing inner skin rubber hydraulic forming method

Abstract

The invention provides a double-curvature rectangular reinforcing inner skin rubber hydraulic forming method. The method involves a rubber hydraulic forming die, the edge covering allowance is increased along the edge of the die on the basis of the unfolding size of the die line, due to the fact that the compression type cushion layer plates are laid step by step, the deformation of the blank is gradually increased, and the purpose of gradually forming is achieved; and rubber hydraulic forming is carried out, an inner hole part is opened up, and forming is finished. According to the method, the rubber hydraulic forming technology is utilized to obtain the product which is stable in quality and meets the design requirements; and wrinkles caused by over-fast flowing of the materials can be effectively controlled, and manual knocking modification amount is greatly reduced.

Description

technical field [0001] The invention belongs to a forming technology in the field of aircraft sheet metal parts manufacturing, which is suitable for aluminum alloy thin plates and lid-like inner skin parts with complex and sharply changing surfaces. Complex skin rubber hydroforming method. Background technique [0002] The process of aircraft sheet metal parts is complex and strictly controlled. For example, the reinforced side parts of the inspection hatch on the aircraft are large in size and thin in material. They are a double-curved rectangular reinforced inner skin. The surface of the part must be glued to the theoretical surface of the fuselage, and the requirements for surface quality and forming accuracy are very high. Due to the complex structure, it is difficult to choose an economical and applicable forming method that can meet the quality requirements. [0003] This kind of double curvature strengthens the forming of the inner skin part, generally adopts two kin...

AI Technical Summary

Problems solved by technology

In addition, the forming accuracy and surface quality of parts are poor, and the scrap rate is high

For glued skin parts, the surface quality and shape accuracy requirements are high, and the use of drop forming can no longer meet the requirements

The second is conventional deep-drawing forming. Due to the thin material and deep ribs, during the deep-drawing process, the sheet is easily cracked at the corner R of the rib flange, and the material shrinks at the flange plane to cause wrinkles, and the edge of the sheet Loose and uneven, secondly, due to the springback of the parts, the depth of the ribs is not enough, and some parts are deformed after heat treatment, and it is necessary to add tires and manually correct the shape, so that the surface quality of the formed parts cannot meet the bonding requirements

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