Bend deduction for sheet metal. By: Moritz Walter. The bend deduction is the amount the sheet metal will stretch when bent as measured from the outside edges of the bend. The U- punch forms a U- shape with a single punch. Calculation bend deduction. Following steps are followed to calculate bend deduction. Calculating Bend Allowance In my previous post I talked about K- Factor, Bend Deduction , K- Factor Article by Saeed Mojarad ( CSWE) created June 6, Bend Allowance , , Bend Deduction what they mean in sheet metal design. This method tells us how much we have to add or subtract to get exactly what we want.
Bend deduction usually refers to the amount of back, but also a different simple algorithm to describe the process of sheet metal bending. The K factor of your metal sheet , the calculation of sheet bend deduction may require a few different sample bends. Step: 1 Consider a sheet metal blank of known thickness size material ( For example 150X150X1mm) Step: 2 Bend sheet metal part at 90 degree. Accurate value of bend deduction / for allowance is calculated by reverse engineering. Calculation for Bend Deduction / Allowance. Bend deduction table Bend deduction tables for are used to calculate flat pattern layouts. In reviewing a couple for dozen bend deduction charts from a variety of sources I couldn' t find any that agreed with another, with the exception of a single number here there.
Often bend allowances are calculated for a sheet metal part used to make costly tooling production parts that require a lot of labor to produce. To use a sheet metal bend table to calculate unfolded lengths. The value of the bend allowance that comes from sheet metal suppliers are provided in bend tables , manufactures, as well as engineering textbooks bend table looks pretty much like the following excel spreadsheet. The formed bend radius is dependent upon the dies used , the material properties the material thickness. 33 Solid Works , , plug your values into a design software such as Solid Edge Pro- Engineer.
Calculate BEND ALLOWANCE OR BEND DEDUCTION. on “ Fabrication Formulas.
When a sheet metal part is bent, it physically gets bigger. The final formed dimensions will be greater than the sum total of the outside dimensions of the part as shown on the print— unless some allowance for the bend is taken into account. Many will say material “ grows” or “ stretches” as. 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. Bend Allowance and Bend Deduction are not interchangeable terms, so understanding when your parts are using one or the other, or if the parts are using both will help.
bend deduction for sheet metal
Understanding Bend Allowance Your Inventor sheet metal parts will use a Bend Allowance when you have your unfold method set to use a Kfactor. 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. When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched.