The bending coefficient, also known as the bend allowance or bend deduction, is a parameter used in sheet metal bending to calculate the flat pattern length of a bent part. It represents the amount of material that is consumed or displaced during the bending process.
When a sheet metal part is bent, the inside radius of the bend experiences compression, while the outside radius experiences stretching. This results in a change in the overall length of the sheet metal. The bending coefficient considers this length change and helps determine the final flat pattern length.
The bending coefficient is typically expressed as a ratio or a percentage. It is calculated by considering factors such as the material thickness, bend radius, and the type of bend (e.g., V-bend, U-bend). The bending coefficient can vary depending on the specific bending process and material used.
To calculate the bending coefficient, various methods and formulas can be used, such as empirical formulas based on experience or mathematical calculations based on the geometry of the bend. These calculations help determine the amount of material that needs to be added or subtracted from the initial flat pattern length to obtain the correct final bent shape.
The bending coefficient is an essential parameter in sheet metal fabrication, as it helps ensure the accurate and precise production of bent parts with the desired dimensions and shape.