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Drawing method of bending expansion diagram: direct expansion, and the expansion size is obtained by adding the bending coefficient to the internal size.

Calculation method of internal size plus bending coefficient;

When the R angle in bending is less than or equal to the thickness of the material, it is expanded at an acute angle, and the expansion formula is:

22+56+0.8+56+0.8+22+0.8 =158.4 (the dimensions of 22 and 56 are the shape minus the material thickness).

The bending coefficient is the length of the plate after bending. Different materials, different thickness plates and different bending dies have different bending coefficients.

Extended data:

Calculation of bending expansion size by stamping expansion coefficient in bending expansion diagram;

A: length of straight side (A 1 and A2 on both sides of A2) R: size of R when bending T: material thickness P: expansion coefficient W when bending: bending angle π of internal R: 3.1416.

Then: the expanded length after expansion is l = a1+a2+w/360 * 2 * 3.1416 * r * p.

In computer aided design, interactive technology is essential. Interactive CAD system means that when users design with computer system, people and machines can exchange information in time. With the interactive system, people can conceive, sample and modify at the same time, and the display results of each step can be seen from the screen of the graphic terminal at any time, which is very intuitive.

The main function of graphic conversion is to connect the user coordinate system and the graphic output device coordinate system; Translation, rotation, scaling and perspective transformation of graphics; Graphic transformation is realized by matrix operation.

Baidu encyclopedia-bending expansion coefficient

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