First, when the relative wall thickness of angle R is very small, it is calculated as a bending buckle, such as 1 thickness minus 1.75 (generally determined according to the specific experience of each company), 2 thickness minus 3.5, etc.
Second, when the R angle is large, the center line (that is, the center line of the inner and outer lines) is taken as the expansion size.
Extended data:
When the sheet metal is bent and unfolded, one side of the material will be stretched and the other side will be compressed, which is affected by the following factors: material type, material thickness, material heat treatment and processing bending angle.
PROE bending coefficient calculation formula:
When bending and flattening sheet metal, PROE automatically calculates the length of the material. The calculation formula is as follows:
L=0.5π×(R+K coefficient× t )× (θ/90)
L: expanded length of sheet metal.
R: the inner diameter of the elbow.
T: material thickness
θ: Bending angle
Y coefficient: a constant determined by the position of the nerve bending line, with a default value of 0.5 (so-called "bending line"). The default value of the initial bending factor can be set in the configuration.
In the practice of sheet metal design, the commonly used flattening formula of sheet metal is based on k coefficient, and the value range is 0 ~ 1, which indicates the resistance of material to stretching when bending. The relationship with y coefficient is as follows
Y coefficient =(π/2)×k coefficient
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