o Contains all of the flattened part

o Has sides that are each either parallel or perpendicular to the sides of the material stock.

o Encloses extra material around the flattened part for various purposes, such as carrier strips and cutting strips.

o Analysis is based on a forming simulation which uses a finite element analysis derived from the part’s CAD model and the properties of the selected material.

o More accurate than geometric flattening for formed and drawn automotive components and similar complex stampings.

o Generally slower than geometric flattening (very complex parts sometimes require more than one minute to flatten, although the great majority require far less time).

o Analysis is based on unfolding of CAD model geometry, and neither takes into account material properties nor simulates the forming process.

o Accurate for “mostly developable” parts, that is, parts consisting primarily of flat planar surfaces and simple bent or rolled surfaces, with a few small, isolated deformed features like gussets and stiffening beads. These types of parts are common in the agriculture/construction equipment and hi-tech industries.

o Generally faster than FEA flattening.

o FEA – Plastic and elastic material behaviors considered: takes into account both the elasticity-related material properties (including Young’s modulus and Poisson’s ratio) and the plasticity-related material properties (including K, the strain-hardening coefficient, N, the strain-hardening exponent, and R, the Lankford parameter, average) . This is the default in starting point VPEs.

o FEA – Only elastic behaviors considered: takes into account only the elasticity-related material properties (including Young’s modulus and Poisson’s ratio). Because only elastic behavior is modeled, blank size estimates are slightly larger with this option than with the “Plastic and elastic” option.  Some users prefer this approach as it is slightly more conservative for estimating material usage and costs.

o Geometric Unfolding: Select this if you don’t want to use FEA flattening.

o Mid-Surface: specifies that the mesh should be imposed midway between one side of the part material and the other side of the part material. A mid-surface mesh basically represents the neutral surface of the part. This is the default in starting point VPEs.

o Larger Area Side: specifies that the mesh should be imposed on the larger-area side of the part material.

o Smaller Area Side: specifies that the mesh should be imposed on the smaller-area side of the part material.

o No: specifies that the mesh (see Surface for Flattening, above) should not be applied to portions of the material surface that will be removed to form a hole. This is the default in starting point VPEs.

o Yes: specifies that the mesh (see Surface for Flattening, above) should be applied to portions of the material surface that will be removed to form a hole.

o aPriori Selected: specifies that the flattening calculation should be based on the ram direction chosen by aPriori—see Ram Direction for Transfer Die. This is the default in starting point VPEs.

o Average Surface Normal: specifies that the flattening calculation should be based on a ram direction that is the average direction of the normal to the part’s surfaces.