Sheet Metal Development Length Formula

Bend deduction bd the amount removed from the sum of the two flange lengths to obtain a flat pattern.

Sheet metal development length formula.

The formula for this is sb 43r 1 372t r the radius on the inside curve of the bend. 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. Calculate the setback and then subtract it from the sum of two outside dimensions as follows.

Material thickness mt the gauge of the material in decimal form. T the thickness of the sheet or plate 2 000 2 000 i0 125 developing the flat blank length for the above drawn part. Transition patterns available flat pattern segments lobsterback bend elbow ellipsoidal dome head tee offset tee square and rectangle to round frustum cone. Punch edge radius in.

In this formula the initial length is 300 mm. The length of the median plane is the unfold length which can be obtained by the following formula. Length of the flat blank in preparation for bending. You only have to insert interior angle flange lengths k factor inside radius and material thickness.

Bend allowance ba the amount of added to the sum of the two leg lengths to obtain the flat pattern length. Sheet metal development calculator is a really simple tool for calculation of development of a sheet metal part. 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. Therefore after bending total sheetmetal part length a b is greater than sheet metal flat length.

Where ba is bending allowance. Bend deduction is equal to the difference between the total sheet metal length after bending and flat length. Die edge radius in. Where r is the radius of the arc on the neutral axis.

Bend angle b the inside angle between the two legs or flanges of a bend. We know that ba is the length of the arc on the neutral axis. Ultimate tensile strength psi.