How To Find K Factor In Sheet Metal
The k factor is usually somewhere between 0 3 and 0 5.
How to find k factor in sheet metal. To calculate the bend allowance the k factor and the derived coefficient called the y factor insert the thickness and initial length of the sheet into the cells on the left. Y factor k factor x π 2. The k factor is defined mathematically as t mt where t is the neutral axis location and mt is the material thickness. Best way to calculate k factor in sheet metal is by reverse engineering.
The area within the sheet defined as the neutral axis does not get compressed on the inside of the neutral axis or expanded on the outside. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness. Bending angle is 90. Publications such as machinery s handbook give general recommendations for k factors but the best practice is to determine them from actual tool set ups and materials.
Typically the k factor is going to be between 0 and 5. You can also use our flat pattern calculator for blank size calculation. K factor in sheet metal bending is a constant used to calculate sheet metal flat length or flat pattern. How k and y factors affect metal bending.
In this article we will discuss sheetmetal bend deduction bend allowance k factor y factor and sheet metal flat pattern calculations. In my previous post i talked about k factor bend allowance and bend deduction and what they mean in sheet metal design. K factor is a coefficient that is affected by the brake tooling as well as the material. Cad tools use k factor to calculate sheet metal blank size.
You ll need the k factor to find the y factor. K factor 180 x ba π x complementary bend angle x mt ir mt 2. After bending the sheet insert the inner radius and flanges a and b. This is defined as the length of the neutral fibre from the beginning to the end of the arc generated by the bend.
Because of the specific properties of any given metal there is no easy way to calculate that value perfectly hence the chart in figure 2. In order to find the k factor you will need to bend a sample piece and deduce the bend allowance. Finding y factor for sheet metal bending. So if the thickness of the sheet was a distance of t 1 mm and the location of the neutral axis was a distance of t 0 5 mm measured from the inside bend then you would have a k factor of t t 0 5 1 0 5.
Calculating the k factor 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. Now let s see how we can obtain these values for a specific sheet. You can use this k factor calculator to calculate k factor using reverse engineering method. K factor a constant determined by dividing the thickness of the sheet by the location of the neutral axis which is the part of sheet metal that does not change length.
Flat blank dimension l1 l2 l3.