Sheet Metal K Factor For Press Brake

Punches and holders found on press brake equipment.

Sheet metal k factor for press brake.

A big driver behind this is the use of the term minimum bend radius on many drawings and how that term is interpreted. The formula see bending formulas is. From there we can calculate the k factor and the bend deduction. K factor k the ratio of the position of the neutral axis to the material thickness.

I am forming plastic not metal but i am applying metal bending principles to my application after a few years of iteration we have developed an accurate flat pattern method for our tank bending operations. Our design engineers typically use a factor of 0 4 for our air formed press brake parts. We multiply this factor by the material thickness to determine the distance the neutral axis shifted toward the inside radius during bending. Thick we multiply this thickness by the k factor to arrive at 0 027652 0 446 0 062.

The k factor is the percentage of the material thickness where there is no stretching or compressing of the material for example the neutral axis. Air bending one of the three types of bending for sheet metal where the outside mold line is not pressed against the die. Ba π 180 inside bend radius. Bend allowance angle π 180 radius k factor thickness.

We will start by calculating the bend allowance. Thick thinned in the bent areas along the circumference and wrapped into a rectangle with radiused corners. When you bend sheet metal the neutral axis shifts toward the inside surface of the bend. Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees.

Many see minimum bend radius and reach for the sharpest punch they have the one with the smallest punch tip radius. The k factor is the ratio of the neutral axis location t to the material thickness mt. The location of the neutral axis varies and is based on the material s physical properties and its thickness. I had a question on k factors for our 3 d modeling software.

The k factor in sheet metal working is the ratio of the neutral axis to the material thickness. The line where the transition from compression to stretching occurs is called the neutral axis. After bending the sheet we need to do some measurements as shown in figure 2. A k factor average of 0 4468 is used for most bending applications.

If a material is 0 062 in. For this simple l bracket i will use a k factor of 0 42. Our tanks are formed from sheet stock typically 0 25 in. An average and commonly used value for the k factor is 0 446.