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Bend deduction sheet metal example.
When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched.
Therefore the bend allowance added to the flange lengths is equal to the total flat.
If you compare the length of this part before and after the bending you re going to find that they re different.
Bending is one of the most common sheet metal fabrication operations.
In the example above it is indicated by a dashed blue line.
Understanding the bend deduction and consequently the bend allowance of a part is a crucial first step to understanding how sheet metal parts are fabricated.
The bend radius refers to the inside radius.
From there we can calculate the k factor and the bend deduction.
Working with an included bend angle of 60 degrees a material thickness of 0 062 in an inside bend radius of 0 062 in and a bend allowance ba of 0 187 in you get a negative bend deduction.
When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched.
The bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length.
The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend.
This is done through the application of force on a workpiece.
After bending the sheet we need to do some measurements as shown in figure 2.
The force must exceed the material s yield strength to achieve a plastic deformation.
That means you subtract the negative bd again the same as adding when doing the flat blank calculation.
August 29 2020.
Although it is an option for calculating a bend in some cad programs such as solid works it is not often referred to in the actual manufacturing process since.
Bend allowance is a measure of how much extra material is required to accommodate a bend in sheet metal this is a function of the bend angle bend radius thickness of the material and a variable called the k factor bend allowances vary based on the angle of the bend the type and thickness of the material and the method used to create the.
The bend allowance is the amount of the neutral axis that bends.
Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees.
Well when a sheet is bent in the press brake the part of the sheet close to and in contact with the punch elongate to compensate for the given bend.
We will start by calculating the bend allowance.
The formed bend radius is dependent upon the dies used the material properties and the material thickness.
In the example above it is indicated by a dashed blue line.
Understanding the bend allowance and consequently the bend deduction of a part is a crucial first step to understanding how sheet metal parts are fabricated.
