Large aircraft skin blank structure and skin stretching forming method

Abstract

The invention relates to an aviation sheet metal part and a forming method thereof, belongs to the technical field of aeronautical manufacturing, and discloses a large aircraft skin blank structure and a skin pull stretching method. According to the large aircraft skin blank structure, the end of a skin blank is provided with a structure protruding outwards in the stretching direction. A skin is of the above skin blank structure. The skin stretching forming method comprises the following steps that firstly, a jaw of a stretching machine is lifted up by a certain angle and is bent, and the twoends of the skin blank are clamped in the jaw of the stretching machine; secondly, the jaw of the stretching machine oppositely moves in the horizontal direction, and the skin blank is warped; thirdly, the height of the jaw of the stretching machine is reduced, and the skin blank is in contact with the face of a skin stretching mold; and fourthly, the jaw of the stretching machine does stretchingmotion in the direction away from the skin stretching mold in the horizontal direction, and the skin blank and the face of the skin stretching mold are completed stretched and attached. The large aircraft skin blank structure and the skin pull stretching method have the following advantages that the skin quality is improved, and therefore the more excellent aircraft pneumatic appearance is achieved.

Description

technical field [0001] The invention relates to an aviation sheet metal part and a forming method thereof, belonging to the technical field of aviation manufacturing. Background technique [0002] Aircraft skin stretch forming technology is a forming technology for aircraft sheet metal parts. Compared with other sheet metal forming technologies, skin stretch forming technology has the technical advantage of small part springback, and is especially suitable for large multi-dimensional curvature masks. It is widely used in the aerospace industry for the molding of leather parts. However, due to the inconsistency of the radians of the skin in different parts and regions, in order to ensure that the skin material does not break and minimize the generation of slip lines on the outer surface when stretching complex variable-curvature skin parts, there are often After the skin is formed, the curvature of the shape does not meet the requirements of the engineering drawings, which a...

AI Technical Summary

Problems solved by technology

However, due to the inconsistency of the radians of the skin in different parts and regions, in order to ensure that the skin material does not break and minimize the generation of slip lines on the outer surface when stretching complex variable-curvature skin parts, there are often After the skin is formed, the curvature of the shape does not meet the requirements of the engineering drawings, which affects the acceptance of the skin, and the assembly stress caused by the poor conformity of the shape and curvature seriously affects the flight safety of the aircraft

[0003] The traditional skin blank has a simple rectangular or square structure, which is not conducive to obtaining a relatively uniform deformation of each part of the skin during the stretching process, especially when the curvature of the shape of different parts of the skin changes significantly , the inhomogeneity of the plastic deformation of the skin is more significant, which can easily lead to defects such as slip lines and cracks in the local area of ​​the skin due to the large amount of plastic deformation, and the radian of the local area of ​​the skin is unqualified

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