Bend Allowance Table For Sheet Metal

Most sheet metal materials will conform to the calculations.

Bend allowance table for sheet metal.

The required die width is 12 mm and tonnage per meter is 22. L unfold length a outside size b outside size k k factor none 90 bend unfold according to the neutral layer the distance from neutral to sheet inner side is t 3 inner r can refer to the above chart. Sheet metal bend radii if these guidelines are not followed more research and or some form of analysis may be requried. From there we can calculate the k factor and the bend deduction.

The bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length. This page also includes a link to a on line sheet metal bend allowance calculator. Table 1 preferred recommended 90 degree bend radii for various sheet metals. The tables below show bend radii and minimum bend sizes for materials and tooling combinations stocked by protocase.

Understanding the bend deduction and consequently the bend allowance of a part is a crucial first step to understanding how sheet metal parts are fabricated. The bend allowance bend deduction of the sheet metal specified in k factor by configuring and utilizing a sheet metal gauge table we can speed up the process of selecting the correct wall thickness based on gauge value and selecting the correct bend radius based on available tooling we can also automate the process of selecting the appropriate k factor. It is possible to choose other bends but tooling charges may apply. Calculate unfold size with bend allowance chart.

We will start by calculating the bend allowance. The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance. The following illustration shows the equation calculation for determining the bend allowance when forming sheet metal. The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend.

Therefore even a simple bench with enough room to bend 3 m pieces will do the job. Therefore the bend allowance added to the flange lengths is equal to the total flat length. You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k. Bend forming 0 l a b 0 43t t thickness deduction 0 43t.

The material thickness will be measured in decimal form not by the gauge number. The lowest common bench capacity is around 100 tonnes. When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched. After bending the sheet we need to do some measurements as shown in figure 2.