When it comes to sheet metal bending, calculating the flat length of the sheet or creating a CAD when unfolding the sheet, the goal is always to improve production efficiency. The simpler the calculation, the better, including the bending coefficient calculation formula. In fact, if precise sheet metal accuracy is not required, the bending coefficient of the bending machine can be calculated using a simple method.
The simplest calculation method for the bending coefficient of a bending machine is the 90-degree bending coefficient calculation formula: 1.7 times the material thickness. How is this formula used? In a 90-degree sheet metal bending process, the material thickness is subtracted from the right angle bending. For example, if the material is a 1mm iron sheet and the bending angle is 90 degrees, with bending sizes of 100 degrees and 50 degrees, the calculation for the flat length is: 100 + 50 - 1.7 = 148.3mm. However, due to slight variations in the bending dies used by different sheet metal factories, there may be minor errors. Manufacturers with lower requirements for sheet metal forming can use the calculated values directly, while those with higher requirements can make slight adjustments.
Sheet metal bending involves not only 90-degree bends but also non-90-degree bends. Is there a simple calculation method for non-90-degree bends?
For accurately calculating the bending coefficient of non-90-degree bends, there is a calculation formula that utilizes the concept of the neutral layer to calculate the arc length of the bending. This ultimately determines the bending coefficient.
There is a special angle where a simple method can be used to calculate the bending coefficient. When the bending angle of the sheet metal is 135 degrees, the bending coefficient can be reduced by 0.5 times the material thickness. For example, if the material is a 1mm iron sheet and the bending angle is 135 degrees, with bending sizes of 100 degrees and 50 degrees, the calculation for the flat length is: 100 + 50 - 0.5 = 149.5mm. This method can also be applied to other sheet metal thicknesses. However, it is only applicable to 135 degrees and cannot be used for other angles.
There is another special angle in sheet metal bending, known as flanging or hemming, which can be calculated using a simple method. The bending coefficient is equal to 0.4 times the sheet metal thickness. For example, if the material is a 1mm iron sheet and the bending is a flange, with bending sizes of 100 and 10, the calculation for the flat length is: 100 + 10 - 0.4 = 109.6mm. This method provides accurate results, but there may be slight variations depending on the equipment used by different sheet metal factories.
