Sheet Metal Development Length Formula

If you have a sheet metal bending product as shown in above picture with two legs of length x and y and you unbend it you will see that total length of the unbend sheet will not x y rather the length will be x y ba.

Sheet metal development length formula.

Bend allowance ba the amount of added to the sum of the two leg lengths to obtain the flat pattern length. We know that ba is the length of the arc on the neutral axis. In this formula the initial length is 300 mm. Length of the flat blank in preparation for bending.

Calculate the setback and then subtract it from the sum of two outside dimensions as follows. L a x b x α 360 2π r t1 1 2 here where α 90 the result is l a 1 57 r t1 x 1 2 b. By replacing initial length leg length 1 and 2 in the above equation we can calculate the bend allowance as follows. Material thickness mt the gauge of the material in decimal form.

The length of the median plane is the unfold length which can be obtained by the following formula. T the thickness of the sheet or plate 2 000 2 000 i0 125 developing the flat blank length for the above drawn part. Cells on the right will output the desired values. Sheet metal development calculator is a really simple tool for calculation of development of a sheet metal part.

Bend angle b the inside angle between the two legs or flanges of a bend. Ultimate tensile strength psi. Punch edge radius in. Where ba is bending allowance.

The length of the arc for this scenario can be calculated as. Where r is the radius of the arc on the neutral axis. With this free online tool we quickly get the sheet metal bend deduction and therefore the sheet metal blank initial flat length from the finished part measurements. You only have to insert interior angle flange lengths k factor inside radius and material thickness.

Therefore after bending total sheetmetal part length a b is greater than sheet metal flat length. Transition patterns available flat pattern segments lobsterback bend elbow ellipsoidal dome head tee offset tee square and rectangle to round frustum cone. Bend deduction is equal to the difference between the total sheet metal length after bending and flat length.