Calculating K Factor Sheet Metal Bending

For example if the value of k factor for given material thickness and bending machines is known.

Calculating k factor sheet metal bending. The inside radii are based off of a standard air bend force chart. The k factor is fundamental to designing precise sheet metal. Typically the k factor is going to be between 0 and 5. In order to find the k factor you will need to bend a sample piece and deduce the bend allowance.

Sheet metal bend allowance chart pdf. The k factor is the most important and elusive variable of bending because it varies both as a function of the material and according to parameters such as angle and tooling. When sheet metal is bend the inside bending surface is compressed. Then input the bend angle to get the arc length bend allowance and bend deduction.

The part of the material that bends. As shown in figure 1 below k t t. You can easily modify the material thickness inside radius and k factor for each thickness at the top of each column. What is the k factor.

The k factor is the ratio between the distance from the neutral layer to the bent inner surface and the thickness of the sheet metal. The below microsoft excel chart is for even numbered gauges 8 through 24 and has a default k factor of 33 for each. We will start by calculating the bend allowance. Sheet metal bending methods design tips k factor bending is one of the most common sheet metal fabrication operations.

The k factor is defined as the ratio between the material thickness t and the neutral fibre axis t i e. Input material thickness and and inner radius to get the data of k factor y factor neutral layer. Whereas the outer surface is stretched. This change in sheet length depends on the position of neutral axis or k factor.

Sheet metal flat length can be calculated using cad softwares. Since the k factor is based on the property of the metal and its thickness there is no simple way to calculate it ahead of the first bend. After bending the sheet we need to do some measurements as shown in figure 2. The k factor is a key basic concept in solidworks sheet metal design and must be understood in order to learn sheet metal design and fabrication well.

Best way to calculate k factor in sheet metal is by reverse engineering. From there we can calculate the k factor and the bend deduction. Also known as press braking flanging die bending folding and edging this method is used to deform a material to an angular shape. Calculate k factor bend allowance and y factor for sheet metal bending.

And if you know the bend allowance you can extract the k factor from it. K factor in sheet metal bending is a constant that is used to calculate sheet metal flat length. The k factor is nothing more than a multiplier that can give you an accurate value for the relocated neutral axis. Once you know the k factor you can use it to predict the bend allowance for various angles.

Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees.