What Is Bend Allowance?
Bend allowance is an important factor in achieving accurate results in press brake bending.
The metal sheet undergoes stretching on the outside and compression on the inside due to the forces of tension and pressure during the bending process.
Therefore, it is necessary to consider both bend allowance and bend deduction in the flat pattern of the workpiece to achieve the final accurate bending result.
Both bend allowance and bend deduction are used in determining the dimensions of the flat workpiece drawing.
Bend allowance refers to the length of the neutral axis between the bend lines, and it is the length added to the flange length to get the bend allowance.
The value of bend allowance is calculated as the difference between the total flat length and the total flange length of the workpiece in the flat pattern.
To calculate the bend allowance, the following parameters are needed: plate thickness, bending angle, internal radius, K factor, and others.
Bend Allowance Calculation
The bend allowance calculation formula is:
Where B is the bending angle, IR is the inner radius, and MT is the thickness of the plate, K is the K factor.
Bend Allowance Chart
In addition to the bend allowance formula, it can also be determined through the bend allowance chart.
The bend allowance and bend deduction are essential parameters for achieving accurate results in press brake bending.
To obtain the correct dimensions of a flat workpiece drawing, both of these values must be taken into consideration.
The bend allowance refers to the length of the neutral axis between the bending lines, and is calculated as the difference between the total flat length and the total flange length of the workpiece in its flat pattern mode.
The bend deduction, on the other hand, is equal to the difference between the total flange length after bending and the total flat length.
It is used to determine the flat pattern length of the sheet metal and the size of the workpiece.
To calculate the bend allowance, factors such as plate thickness, bending angle, internal radius, K factor, and others must be taken into account.
The bend deduction can be obtained once the bend allowance is known.
You can either use a formula or a bend allowance chart to calculate the bend allowance.
For more information on bending and our press brake products, you can read our blog or contact our product experts.
ADH not only offers press brakes, but also panel benders, laser cutting machines, shearing machines, and more. Our team of experts is available to help you with your needs.