Neutral Factor Sheet Metal

K factor in sheet metal bending is a constant used to calculate sheet metal flat length or flat pattern.

Neutral factor sheet metal.

In sheet metal design the k factor is used to calculate how much sheet metal one needs to leave for the bend in order to achieve particular final dimensions especially for between the straight sides next the bend. I had a question on k factors for our 3 d modeling software. Flat blank dimensions are calculated by determining the path length along the neutral axis. This is defined as the length of the neutral fibre from the beginning to the end of the arc generated by the bend.

The k factor is a constant determined by dividing the material thickness of the sheet by the location of the neutral axis. For example the following part that has a 90 o bend. 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. In this article we will discuss sheetmetal bend deduction bend allowance k factor y factor and sheet metal flat pattern calculations.

It is the fraction of material thickness from the inside of the bend to the neutral axis. After bending the sheet insert the inner radius and flanges a and b. The location of the neutral axis varies and is based on the material s physical properties and its thickness. 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.

When you bend sheet metal the neutral axis shifts toward the inside surface of the bend. The k factor is the ratio of the neutral axis location t to the material thickness mt. The neutral axis does not suffer any change of length during a bending operation. The line where the transition from compression to stretching occurs is called the neutral axis.

Our design engineers typically use a factor of 0 4 for our air formed press brake parts. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness. The k factor in sheet metal working is the ratio of the neutral axis to the material thickness. Use the known k factor and the known inner bending radius to calculate the bending radius of the neutral line.

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. The location of the neutral axis is specified with the k factor.