FormingSuite Training

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The information contained in this manual is Confidential and is provided subject to the terms and conditions ofthe Forming Technologies Software License Agreement. This manual is part of the Support Material referred toin the Agreement.

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Information in this document is subject to change without notice.

2011 - Forming Technologies Incorporated. All rights reserved.

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2011 - Forming Technologies Incorporated ii

Contents

1 Part Definition 1

1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2 Import Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.3 Create Domain on Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1.4 Create Skin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.5 Material Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.6 Split Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.7 Creating Multiple Entities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.8 Operations on Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.8.1 Create Line on Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.8.2 Create Line on Boundary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1.8.3 Splitting a Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1.9 Create Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

1.10 Fill Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1.11 Fill Notches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

1.12 Deleting Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.13 Add to Skin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2 Process Setup 15

2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.2 Generating Mesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2.3 Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

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2.4 Punch Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.5 Forming Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.5.1 Draw Die . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.5.2 Form Die . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.6 Binder Wrap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.7 Insert Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.8 Blankholder Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.9 Draw Beads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.10 Pressure Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.11 Pilot Hole(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2.12 Multiple Forming Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

2.13 Typical Analysis Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

3 Process Definition 31

3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.2 Entering the Process Definition Workbench . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.3 Defining the Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.3.1 Inserting an Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.4 Binder Wrap Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.5 Trimming Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

3.6 Generating Mesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.7 Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

3.8 Forming Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.8.1 Draw Die . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.8.2 Form Die . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.9 Punch Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3.10 Blankholder Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.11 Draw Beads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

3.12 Pressure Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

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3.13 Multiple Forming Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

4 Tool Definition Workbench 47

4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

4.2 Starting an Incremental Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

4.3 First Form Geometry and Blank Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

4.4 Prepare Binder Wrap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

4.5 Define Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

4.5.1 Tooling Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

4.5.2 Tool Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

4.5.3 Tool Positioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

4.5.4 Tooling Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

4.5.5 Punch Movement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

4.5.6 Blankholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

4.5.7 Pressure Pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

4.5.8 Pilot Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

4.5.9 Generating Tooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

4.5.10 Importing Tooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

4.6 Show Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

4.7 Editing the Tool Mesh Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

5 Incremental Workbench 59

5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

5.2 Incremental Settings - Templates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

5.3 Solving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

5.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

5.4.1 Safety Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

5.4.2 Forming Zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

5.4.3 Safety Margin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.4.4 Thickness Strain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

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5.4.5 Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

5.4.6 Major Strain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.4.7 Minor Strain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.4.8 Equivalent Strain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.4.9 Equivalent Stress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.4.10 Principal Strain Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

5.5 Forming Limit Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

5.5.1 Margins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

5.6 Die Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.7 Exporting the Part Boundary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

5.8 Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

5.8.1 Curved Box Incremental Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

5.8.2 Multistage Crossmember Incremental Analysis . . . . . . . . . . . . . . . . . . . . . . . . 77

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Chapter 1

Part Definition

1.1 Introduction

FormingSuite includes a basic set of geometry editing tools. These tools are designed to help one clean up theimported model and prepare it for applying forming conditions, if necessary. They can be used to perform simpletasks such as deleting entities, creating entities, or splitting surfaces. The software does not include tools forcreating surfaces. If major changes are required to the topology of the geometry, they should be done in yourCAD system prior to exporting the model and importing it into Forming Suite.

1.2 Import Geometry

To begin the analysis, open a 3D geometry file or a surface model. This geometry file can be in IGES, STEP, orVDA file format and must contain solid or surface geometry. A wireframe model will not contain enough data tocomplete the analysis.

To import geometry select New Forming Analysis for the start menu and the import dialog will automatically openprompting you to select a file. Indicate the file format, IGES, STEP, or VDAF from the drop down menu, selectthe file, and press Open.

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CHAPTER 1. PART DEFINITION

Alternatively, you can import geometry without using the start menu shortcut, by selecting the New Project icon

and then selecting the first wizard prompt (shown below), which will open the import dialog.

You can also open the import dialog by selecting the Geometry Workbench icon after the New Project icon

followed by selecting the Import Geometry icon and the import dialog will open.

To perform sheet metal formability analysis on a part, FormingSuite requires a skin (surface quilt) representingthe mid-plane, inner or outer surfaces. If a solid model is imported, it will contain surfaces describing the top,bottom and edge surface (material thickness) of the part.

During import FormingSuite will separate the model geometry into Points, Lines, Domains, and Boundaries. Adomain is a group of connected and/or tangent surfaces. If the model geometry is a solid, there will be multipledomains. One domain will contain all the surfaces representing the top surface, another domain will contain allthe surfaces representing the bottom surface, and finally a third domain will contain all the surfaces representingthe thickness surface.

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Importing a Solid Model

After FormingSuite has separated the model geometry into the top, bottom, and thickness surface you then needto generate the skin (surface quilt). To generate the skin select the Next: Generate Skin from the wizard or

select the Create Skin icon from the Geometry Workbench toolbar to open the Geometry - Skin Dialog (shownbelow).

Once the dialog is open you need to select which surface (top or bottom) that you would like to use. To this youcan either select the domain from the Feature Tree or you can select the domain by clicking on the side of themodel that you would like to use. In either case, the selected domain will be highlighted.

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Importing a Surface Model

When you import a surface model it will also be separated into domains. When you generate the skin from asurface model (when there is only one domain), you will also need to specify the thickness direction using theGeometry - Material Location Dialog (shown below), which is automatically opened after you define the domain.

The thickness direction is set to middle by default. This assumes the surface is a mid plane. If the importedsurface is not the mid plane, select the Side radio button and the direction arrow will display the thicknessdirection that is being defined. Use the Flip Side button to reverse the direction.

The model below is of a solid part with the outer surface extracted. The image below it shows the proper directionto apply in the Material Location dialog from FormingSuite. You will notice that the arrow points in the direction ofthe material thickness.



1.3 Create Domain on Part

A domain is a group of connected and/or tangent surfaces.

This command will allow you to manually define a group of connected and/or tangent surfaces (domain) that canbe used to define the geometry that will be created in the Skin folder.

NOTE: This function is only available prior to the Skin folder generation.

To access this function select the Create Domain on Part icon to open the Geometry - Define Domain dialog(shown below).

Define a new domain by moving surfaces from an existing domain. Usethe drop-down menu to select the original (source) domain and then se-lect the surfaces to move into the new domain. Move the selected sur-faces into the new domain by selecting the down arrow , and finallyselecting OK to create the new domain. You can use the Add Connectedbutton or the Add Tangent button to propagate your selection.

You can select the group of surfaces, either from the Graphics DisplayArea or from the Feature Tree (you must first Show Details to pick fromthe feature tree)

If you want to put a surface(s) back into the original domain, select the

surface(s) from the lower field and select the up arrow , followed byOK to put the surface(s) back into the original domain.



1.4 Create Skin

This command will allow you to choose which domain from the Part folder that you would like to use to create thegeometry in the Skin folder. This geometry will be used as the baseline for the analysis.

To access this function select the Create Skin icon to open the Geometry - Skin dialog (shown below).

To create the Skin folder select the desired domain either by picking it from the Feature Tree or by selecting itfrom the Graphics Display Area, then click OK to create the Skin branch.



1.5 Material Selection

The next step in preparing the model for analysis is to define the material type and material thickness. Applyinga material is necessary to ensure that the final result properly accounts for the specific material behavior. If youstarted with a solid model the material thickness field will automatically be filled in with the material thickness.

To define the material type and material thickness select the third wizard prompt, this will open the Part Definition- Property dialog.

Select the material type from the drop down menu and input the material thickness. You can edit any of thematerial properties (mechanical, cost, etc.) by selecting the Properties button. Editing the material properties thisway will only edit the material for the specific project. The changes will NOT be reflected in future projects.

Alternatively, to open the Forming - Property dialog box manually, click the material icon .



1.6 Split Surface

To split a surface, select the Split Surface icon from the Part Definition toolbar. Next pick the start and endlocations of the split profile on the boundary of the surface. The points must either by on the boundary of thesurface to split or slightly past, if you are using a line to split. You can also create a closed boundary whichdefines the new surface within another surface by checking the Closed Line option.

Once the profile is defined, select OK to split the surface.

1.7 Creating Multiple Entities

FormingSuite has the ability to create multiple entities (lines, points, etc.). Each function where there is the

possibility to create entities now has a pin icon in the top right hand corner . When this icon is activated itallows you to create an entity without closing the dialog. To close the dialog while creating your final entity, youmust deactivate the pin icon by selecting it prior to creating your final entity. If you have created all your entitiessimply deactivate the icon by selecting it and click OK or cancel.

1.8 Operations on Lines

1.8.1 Create Line on Surface

To draw a line on a surface, select the Create on Surface(s) option under the Operations on Line(s) icon. Nextselect two or more points on a surface and select the OK button in the Geometry - Line On Surfaces dialog tocreate the new line. The Remove Last button will allow you to remove the last point selected. If you are creatinga line with three or more points defining a boundary you will have the option to close the line using the ClosedLine option.



1.8.2 Create Line on Boundary

To draw a line on a boundary, select the Create on Edge(s) option under the Operations on Line(s) icon. Nextselect two points on an edge and select the OK button in the Geometry - Line On Surfaces dialog to create theline. If the line on the edge is previewed incorrectly select the flip icon to invert the direction of line creation.

1.8.3 Splitting a Line

To split a line, select the Split Line option under the Operations on Line(s) icon. Next select the line or edgeby first enabling the required selection filter in the Geometry - Split Line dialog followed by designating the splitproportion and finally selecting the OK button.

Splitting a line may be required for proper application of forming conditions later during the analysis.



1.9 Create Point

You can create a point based on existing geometry such as a line, surface, or surface edge. A point can also becreated based on keying in the X,Y,Z coordinates of the point to be created.

To create a point on a surface edge, select the Create Point icon and the Geometry - Create Point dialog willautomatically open. In the dialog select the edge filter from the top of the dialog followed by selecting the edgethat you want the point to be created on. The point can either be placed at the center of gravity (C.O.G.) of theedge or along the edge by selecting the appropriate option in the dialog. If you select the Point On Line/Edgeoption you define the position of the point by moving the slider or by keying in a proportion from 0 to 1. To createa point on a line, follow the same procedure as above, except select the line from the top of the dialog.

Clicking the Point On Surface radio button will allow you to create a point(s) by clicking the position on a surfacewhere you want that point to be created.

The Manual radio button allows you to create a point(s) by specifying the coordinates.



1.10 Fill Holes

The Fill Holes command allows you to specify holes/cutouts in the geometry that will be removed during the meshgeneration stage. Holes/cutouts can be selected by clicking the edge of each hole/cutout or by box selecting agroup of holes/cutouts. Multiple holes can be selected by holding the Ctrl key. Any hole/cutout that is specifiedfor filling will still be visible on the part geometry, but will be highlighted for filling during meshing.

To access this function select the Fill Holes icon to open the Geometry - Mark Holes to Fill dialog. Once youhave selected the hole(s) to be filled select the OK button and the selected hole(s) will be filled during meshing.

Forming Suite handles filling holes differently if the hole is on one surface or spanning over multiple surfaces.

If the hole is on one surface Forming Suite will ignore the hole and simply mesh the surface, shown below.

If the hole spans over multiple surfaces Forming Suite will first mesh the surfaces and then fill the hole with mesh,shown below.



1.11 Fill Notches

The Fill Notch(es) command will allow you to specify notches in the geometry that you would like to fill duringmesh generation.

To fill a notch you must first draw a line on the boundary of the notch that you would like to fill, as shown below.In order to fill multiple notches you must create a line on the boundary of each notch to be filled.

After creating the line on the boundary of the notch to be filled, select the Fill Notches icon to open theGeometry - Mark Notch to Fill dialog. Once you have selected the line(s) that defines the notch(es) to be filledselect the OK button and the selected notch(es) will be filled during meshing as show below.



1.12 Deleting Geometry

Geometry can be deleted in one of two ways. First you can use the selection filter to highlight and select thegeometry to be deleted, followed by either right clicking and selecting delete from the menu or by pressing thedelete key on your keyboard. Alternatively you can select the geometry to be deleted by picking it form the featuretree under either the Part or Skin folder, followed again by either right clicking or selecting delete or by pressingthe delete key on your keyboard.

Geometry deleted from the Part folder cannot be retrieved without re-importing the original model.

The only reason that you should delete geometry from the Part folder rather than the Skin folder is if that geometryis causing skinning problems or you want to permanently remove the entities.

After deleting any geometry Forming Suite will require you to regenerate before you can continue your analysis.

1.13 Add to Skin

This command will allow you to copy a point(s) and/or a line(s) from the part folder to the skin folder.

NOTE: This function is only available once the Skin folder has been created and the material type andthickness has been applied.

To access this function right-click on the Skin branch in the feature tree(after the Skin branch has been created) and select Add to Skin to openthe Part Definition - Add Entities to Skin dialog shown below.

Highlight the desired entity filter (point or line) and select the entities tobe added. If you wish to add both points and lines to the Skin geometryfirst select the point selection filter and pick your points, then switch tothe line filter and while holding the CTRL key select the line(s) desired.You will then have both points and lines in the entities field, finally selectOK to add the selected entities to the Skin folder.


Chapter 2

Process Setup

2.1 Introduction

When you have completed the steps outlined in the geometry workbench section, you are now ready to definethe parameters for your analysis in the process setup workbench. These parameters include: mesh generationparameters, punch direction, forming process, and any optional forming conditions.

The Finite Element Method

Forming Suite uses a technique called finite element analysis to determine how material is deforming duringthe stamping operation. The term finite element means that the complex part geometry is broken down intothousands of small, simple shapes called elements. This reduces the complexity of the mathematics requiredto determine what is happening at any given point on the part. The analysis becomes a series of thousands ofsimple calculations which can be easily evaluated by a computer.

The simplified representation of the geometry is called a mesh. Each element in the mesh is connected to theneighboring elements at the corners, which are called nodes. These nodes are shared amongst the adjoiningelements.

Figure 2.1: Finite Element Mesh

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CHAPTER 2. PROCESS SETUP

Different types of analyses may require different types of meshes. As mesh elements are made smaller, there willbe more elements and they will more closely match the true geometry of the part. More elements will also resultin an increase in the time required to solve the analysis. Therefore, it is important to make the mesh only smallenough to adequately represent the geometry for the purposes of the analysis. FormingSuite analysis requiresa mesh that models the radii of the part accurately since this is what will have the greatest effect on formability.These radii may be of less significance to a structural analysis.

2.2 Generating Mesh

To generate the blank shape of the part or to perform sheet metal formability analysis FormingSuite must firstmesh the selected skin surface of the part. There are two options that you can choose from to Generate theMesh:

1. Select Generate Mesh from the wizard, or

2. Select the Generate Mesh icon from the workbench toolbar (To use this option you will first need to openthe Process Setup workbench manually either from the Workbench menu, Workbench > Process Setup or

by selecting the Process Setup icon from the workbench wizard toolbar).

The Process Setup - Generate Mesh dialog is shown below.

Chord Deviation:

Chord deviation is a ratio between the local absolute sag and the local mesh edge length.

Chord Deviation = (local absolute sag value) / (local mesh edge length value)

Maximum Element Size:

Maximum element size defines the value for the maximum length of the local mesh edge.



TIP: Always mesh with the default first! The mesh size can always be made smaller if necessary. To inspect the

mesh quality, turn the shading off using the shading icon .

Editing Mesh Parameters

To edit the mesh parameters right-click on Final Form-Shape and select Show Details, and then click the expan-sion icon (plus sign), which is to the left of the Generation Settings to show Chord deviation and Maxim ElementSize leaves. To open the mesh generation settings dialog right-click on either Chord Deviation or Maximum El-ement Size in the feature tree and select Edit to modify mesh settings. The mesh generation settings can alsobe edited by double clicking on either Chord Deviation or Maximum Element Size to open the Mesh Generationdialog.

If the mesh generation settings are changed, the green dot beside the Mesh branch will change to red indicatingthat the feature needs to be regenerated (updated).

There are four options that you can choose from to update the Mesh:

1. Select Regenerate from the wizard,

2. Select the Regenerate icon on the Standard toolbar,

3. Select Regenerate from the Project Menu (Project > Regenerate), or

4. Use the keypad shortcut Ctrl+R.

If you find that you are changing the mesh parameters often, you should change the default mesh parameters.To do this, go to Tools > Settings > Process Setup > Mesh Settings. This setting is only available when no projectis open.



2.3 Friction

When the Process Setup workbench branch is created, the Friction branch is automatically generated prior tomesh generation.

Friction is applied to areas where the material is being drawn through a radius in a draw die and it is also used byforming conditions such as Pressure Pad.

To change the friction coefficient, double click on Friction in the featuretree under General Data or right-click on Friction and select edit from themenu to open the dialog.



2.4 Punch Direction

To perform an accurate sheet metal formability analysis, FormingSuite requires that the punch direction be de-fined. The punch direction should define the movement of the punch.

When performing an incremental analysis, this direction is used to generate the tooling in the Tool Definitionworkbench. If the punch direction is defined in the wrong direction, then the tooling generated will be incorrect.

To define the punch direction, select the Punch Direction Icon or click the Define Punch Direction step fromthe Wizard.

By right clicking on the Punch Direction branch you may Edit the punch direction or Show/Hide Undercut ele-ments.

The Process Setup - Punch Direction dialog box includes three methods to orient the part in the press direction.

Auto

Prescribed Orientation

Manual Rotation

It also includes a Preview Undercut button as well as a Flip button. The flip button allows you to reverse the punchdirection.

1. Auto. Click the Auto radio button to automatically orient the part intoan approximate press position based on a mathematical algorithm.

2. Prescribed Orientation. You can prescribe the punch direction inone of three ways.

You can use a user defined die line to indicate the punch di-rection. Click the Straight Line radio button and select the dieline that you would like to use, and press OK in the ProcessDefinition - Punch Direction dialog box.

You can use a user defined surface to indicate the punch di-rection. Click the Normal to Surface radio button and selectthe surface that you would like to use, and press OK in theProcess Definition - Punch Direction dialog box.

You can key in the X, Y and Z components of the press direc-tion relative to FormingSuites axis system under the DirectionVector heading in the Process Definition - Punch Direction di-alog box. Click the Manual radio button to enable this feature.

3. Manual Rotation. Enter a positive angular value in the RotationIncrement field then click the up and down arrows beside X, Y or Zto rotate the press direction around the X, Y, or Z axis system. Thisfeature is only active when the Manual radio is selected.



When you have created double attached geometry, the punch direction dialog will be reduced to include only theNormal and Auto options, as shown below.



2.5 Forming Process

In the process definition workbench, the forming process is set in the Process Manager table. The setting willinfluence the way the tools interact with the part during forming. You can choose between a Draw Die and a FormDie.

The Forming Process setting also controls how tooling generation will occur in an incremental analysis. If theprocess is set to Form Die, only a punch and die will be generated in the tooling workbench, while if the processis set to Draw Die, the tooling generation system will also generate a binder.

2.5.1 Draw Die

If you are forming a part using a draw die (as illustrated below left) you should use the Draw Die forming process.As material passes over the radius on the die, additional strain is added to the part due to the friction between thepart and the die and the bending and unbending process. These additional strains are not present when a partis manufactured using a form die. The friction and bending effects are automatically considered by FormingSuitewhen the Draw Die setting is turned on. The Draw Die process formulation determines the areas of curvature onthe part and adds the required forces and strains to any material that would flow over them during forming. Note:when applying bend lines manually, the Draw Die process should not be used.

2.5.2 Form Die

If you are forming a part using a Form Die (illustrated below right) you should use the Form Die forming process.This process is typically used in progressive dies and simple flanging operations.

In this type of operation, the blank material is not pulled through a radius; it is simply bent around it. As a result,there are no additional strains produced by friction.



2.6 Binder Wrap

The term "Curved Binder" refers to the situation where the flat blank is bent over a curved surface before formingbegins. This pre-bending (sometimes called "Binder Wrap") helps position the blank material such that there isless variation in draw depth. For example, when a door panel is being formed, if a conventional (flat) binder isused, the middle of the door will be much further from the flat blank than the edges. This will result in higherstrain in the middle of the panel. A curved binder that follows the curvature of the door can be used to even outthe distance from the blank to the finished shape. This will result in a more uniform strain distribution.

By default, the analysis is performed with a default flat binder. In many cases, the actual forming starts with acurved binder that creates a curved blank. The curved blank usually results in more material being availablefor the forming operation. This extra material has a significant effect on the results depending on the formingconditions that were applied.

To run a curved binder analysis you can either import the binder geometry or use the automatic generationfunction. The imported binder shape must be developable, should be large enough to contain the developedblank shape for the model and the draw radius should be continuous and closed. A developable binder is definedas one that has been bent into a simple curve in such a way that if it were flattened, there would be little or noresidual strain in the blank. When meshing this binder, the mesh does not have to relate to the mesh size of thepart.

The imported binder geometry should also be constructed such that they are coincident with the surfaces on thepart that are used for analysis. For example, if the top surface of the part is selected, the curved binder shouldbe coincident with the top surface.

Importing a Curved Binder Model

The curved binder model can be imported as an IGES, STEP, or VDAF. These files would have originally beencreated in a CAD software package.

To import the binder geometry, select the binder icon and choose Import from the menu. You will then need tospecify the file type, and select the binder file that you want to import.

When you import a binder model into the Binder workbench the software will automatically mesh the binder andapply a default tipping direction along the z-axis.

Generating a Curved Binder Model

To generate the binder geometry, select the binder icon and choose Generate from the menu. A curved bindercannot be automatically be generated for all models. Only geometries that closely represent the die face geometrycan be generated.



2.7 Insert Operation

The Insert Operation icon is only available when you have the FASTFORM - Multi-Stage license.

The Insert Operation icon will open the Process Setup - Process Manager Table (shown below).

The process manager allows you to import your stage geometry and allows you to mark which forming conditionswill be applied to each stage. Solid models cannot be used for pre-form geometry and the pre-form geometrymodels should all represent the mid-plane geometry. If lines are required for forming conditions, like draw beadfor example, then these lines should be included in the imported data.

The order that the pre-form geometry is imported is determined by the order in the process table. Therefore, whenimporting the pre-form geometry into the process manager, it is very important to arrange the pre-form geometryas it will be produced in the manufacturing process.



To add operations to the process manager, first select the Add Operation icon , to add a new row to the processmanager table, and then select the import icon under the File Name Path column (circled in the image below).The Add Operation icon will always add the new operation above the highlighted row. In the image below to addOperation 20 you should first highlight the Final Form row prior to selecting the Add Operation icon.



Prior to import of the stage geometry, you also have the ability to select which forming conditions will be appliedto each pre-form geometry by checking the appropriate forming condition or conditions for each operation. Theforming conditions selected will be created in the feature tree under each operation and you will need to define thenecessary parameters for each forming condition (i.e. amount of blankholder force or selecting which surface(s)the pressure pad will be applied to), as shown below. To define the additional parameters, double-click on thespecific forming conditions branch of the feature tree.

To remove an operation, select the Delete Operation icon to remove the highlighted row. You can delete anyof the pre-form geometry, but not the Final Form.

SIGNIFICANT NOTES:

1. The multi-stage solver DOES NOT currently consider the effects of friction from the draw radius in thesolution. These effects can be accounted for by utilizing the Bend Line forming condition on the draw radii.If no bend lines are applied, the Form Die and Draw Die settings will produce the same result. The solutionfor single stage analyses remains unchanged.

2. All preform geometry MUST represent the mid-plane.



2.8 Blankholder Force

FormingSuite has the ability to simulate the effects of a uniformly distributed blankholder force. Blankholder Force(BHF) is applied slightly differently to the three different FTI solvers. For the Coupled Hybrid Inverse solver (CHI)and the Multi-Stage solver, the BHF is modeled as a uniform edge tension to the boundary of the part duringsimulation (the same as the edge tension process condition); however, for the Incremental solver the BHF ismodeled as the actual force on the binder ring of the tooling geometry. In either case, this will lead to additionalstretch in the model and will help reduce wrinkling.

To apply a BHF to your part, select the Blankholder Force option under the Forming Conditions icon.

When you open the Blankholder Force dialog, the outer boundary of the part will automatically be selected andthe only input required is to enter a value for total blankholder force followed by selecting OK to apply this processcondition. You may also use the slider to apply the force as well. Blankholder Force can only be applied to theentire outer boundary.



2.9 Draw Beads

The draw bead forming condition is used to simulate the control of material flow into the die cavity using a drawbead or a lock bead. If a draw bead is constructed out of a number of draw bead sets with different properties,the last part of a set and the first point of the next set should be coincidental. If they are too far apart, there willbe a gap in the draw bead and the material will not be constrained between the two draw bead sets. To apply adraw bead to your part, select the Draw Bead option under the Forming Conditions icon.

To apply a draw bead you will need an existing line on the part (either created in the geometry workbench orimported with the model). Select the line to apply the draw bead to and specify the strain or tension to be applied.

NOTE: When you specify either strain or tension the other will automatically update.



2.10 Pressure Pads

The pressure pad forming condition is used to simulate the effects of a pressure applied to an area of the blankinside the die. This pressure is intended to control the movement of material in the local area. FormingSuite cansimulate this by restraining the movement of the mesh elements in the area under the pad. To apply a pressurepad to your part, select the Pressure Pad option under the Forming Conditions icon.

To apply a pressure pad, select the face(s) to constrain from the part model. The entire surface of the selectedface(s) will be constrained by the simulated pad. After selecting the faces, specify a value for the Pressure or forthe Total Force in the designated text box.

NOTE: When you specify either a pressure or a total force the other will automatically update.



2.11 Pilot Hole(s)

The pilot hole forming condition is used to simulate the effects of pilot holes by constraining the movement of theholes.

To apply a pilot hole to your part, select the Pilot Hole option under the Forming Conditions icon.

To apply a pilot hole select the holes to constrain by clicking on the boundary of the desired hole followed byclicking OK to apply the selection. Multiple holes can be selected by holding the Ctrl key or by window selecting.

NOTE: When defining multiple pilot holes in analyses where no curved binder is used, all of the holes shouldbe located on a single plane that is normal to the tip axis. If a curved binder is used in the analysis, the pilot holesshould be coincident with the binder geometry. This will ensure that no artificial strains are produced during theanalysis.



2.12 Multiple Forming Cases

FormingSuite allows you to quickly evaluate multiple forming cases to compare the effects of different inputs(material, forming process, tipping, or forming conditions) on the analysis results. Unique tipping positions andforming conditions can be applied to each forming cases.

To apply multiple forming cases simply click on the Part Definition branch in the feature tree and select theProcess Definition workbench icon or select Workbench > Process Definition to insert a second Process Definitionworkbench (case) where all the inputs can be modified and solved independent of the previous Process Definitionworkbench (case).

2.13 Typical Analysis Methodology

When analyzing product geometry, the main concern is identifying potential formability issues. This usuallyinvolves a qualitative approach which means that the numerical results are of less importance than the trends.There are a number of variables that can be changed in the tool to influence the strain values but geometricalproblems such as radii and wrinkling are more difficult to remedy. To identify these problems, start by analyzingthe part with no blankholder force.

If the part splits within, you will need to change the geometry or material. A split on the part edge may be remediedby adding extra material during forming and trimming later so this is not as significant. Increasing the blankholderforce at this point would simply exaggerate the splitting problem.

If the part does not exhibit any splitting or excess thinning but does show some wrinkling, increase the blankholderforce (one step at a time) and re-run the analysis. If the new results show splitting and wrinkling is still a problem,some geometry changes may be required. If there are still no splits and the wrinkling problem has been solved,the part should be ready for manufacturing.


Chapter 3

Process Definition

3.1 Introduction

The Process Definition workbench provides an alternate approach for setting up incremental analyses. It allowsusers to explicitly define all of the geometry to be used in the analysis including blank, binder, pre-form andtrim-lines. It provides a simpler way to set up analyses in the case where all of this data is known. The existingProcess Setup workbench (still the default workflow) relies on the inverse or FIT solution to determine the blanksize which is useful when the blank is unknown, but is an unnecessary step if it is known. As such, the twoworkbenches each serve different use cases:

Use the Process Setup workbench when:

The blank size and position is unknown or

You want to get formability results using the CHI (inverse) or FIT (multistage) solver and

You dont have any trimming operations in the process

Use the Process Definition workbench when:

The blank size and position is known and

If you want to include one or more trimming operations in the analysis and

You want to run an incremental analysis without running the CHI or FIT solvers in advance

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CHAPTER 3. PROCESS DEFINITION

3.2 Entering the Process Definition Workbench

The Process Definition workbench is an alternate approach to setting up an incremental analysis. As such, thewizard will not automatically guide you to it. By default, the wizard will guide you to the Process Setup workbench.

To create the Process Definition workbench, finish defining all of the data in the Part Definition workbench (part,

skin, material, etc) and then press the Process Definition icon in the Workbench Wizard toolbar (usuallylocated at the top of the FormingSuite window) or select Process Definition from the Workbench menu.

3.3 Defining the Process

In the Process Definition workbench, you must explicitly define all aspects of the analysis including the blank,binder, form and trim geometries as well as forming conditions. This data is defined in the Process Table.

To open the Process Table after entering the Process Definition workbench, either press the Process Manager

icon or select the Next button from the Wizard. The Process Manager table will appear at the bottom of thegraphics area.



3.3.1 Inserting an Operation

You can insert an additional operations before the currently selected op-

eration by pressing the Insert Operation icon . A dialog will pop up thatlets you specify what type of operation to insert. Options include:

Curved Binder

Form

Draw

Trim

Each type of operation except trimming requires an IGES file containingsurface geometry representing the operation. Geometry of the punch ordie face is ideal for draws or forms and any lines required for formingconditions should also be included in the IGES file.

When the Process Manager table is closed (by pressing the green check mark icon), the geometry will be im-ported and meshed using default parameters and the specified forming conditions will be added to the featuretree.

In the process manager table, check the boxes representing the forming conditions you want to apply in eachoperation. If you want to apply multiple forming conditions of the same type to a single operation, you can add

them using the forming conditions icon on the workbench toolbar.

The only forming conditions currently supported by FAST Incremental are:

Blankholder force (should be applied to all draw dies)

Draw beads (should only be used on draw dies)

Pressure pads

Pilot Holes



3.4 Binder Wrap Operation

The term "Curved Binder" refers to the situation where the flat blank is bent over a curved surface before formingbegins. This pre-bending (sometimes called "Binder Wrap") helps position the blank material such that there isless variation in draw depth. For example, when a door panel is being formed, if a conventional (flat) binder isused, the middle of the door will be much further from the flat blank than the edges. This will result in higherstrain in the middle of the panel. A curved binder that follows the curvature of the door can be used to even outthe distance from the blank to the finished shape. This will result in a more uniform strain distribution.

By default, the analysis is performed with a flat binder. To run a curved binder analysis from the Process Definitionworkbench, you must import the binder geometry. The imported binder shape should be developable and largeenough to contain the blank shape for the model. A developable binder is defined as one that has been bent intoa simple curve in such a way that if it were flattened, there would be little or no residual strain in the blank. Whenmeshing this binder, the mesh does not have to relate to the mesh size of the part.

The imported binder geometry should also be constructed such that they are coincident with the surfaces on thepart that are used for analysis. For example, if the top surface of the part is selected, the curved binder shouldbe coincident with the top surface.

The curved binder model can be imported as an IGES, STEP, or VDAF. These files would have originally beencreated in a CAD software package.



3.5 Trimming Operations

Trim lines should be closed lines defined on the geometry representing the operation prior to the trim and shouldlie on the part (or die) surface. By defining it this way, the trim line should be coincident with (or very close to) themesh of the part being trimmed. Lines can be created on the pre-form geometry and then defined as trim lines,or they can be imported with the geometry of the pre-form.

Once you have the lines required for trimming, double click on the Shapeobject for the trimming operation in the feature tree to bring up the DefineTrim Line dialog.

A list containing all available lines will be shown at the top of the dialog.Select the lines to use for trimming and add them the list of Trim Linesbelow.

If material should be removed from the inside of the trim line, set OuterBoundary to No. If all material outside of the trim line should be removed,set Outer Boundary to Yes.

Press Ok to accept the trim lines and close the dialog.



3.6 Generating Mesh

The meshes for all operations will be automatically generated once the process manager table is closed. EditingMesh Parameters

To edit the mesh parameters right-click on Final Form-Shape and select Show Details, and then click the ex-pansion icon (plus sign), which is to the left of the Generation Settings to show Chord deviation and MaximumElement Size leaves. To open the mesh generation settings dialog right-click on either Chord Deviation or Max-imum Element Size in the feature tree and select Edit to modify mesh settings. The mesh generation settingscan also be edited by double clicking on either Chord Deviation or Maximum Element Size to open the MeshGeneration dialog.

The Process Definition - Generate Mesh dialog is shown below.

Chord Deviation: Chord deviation is a ratio between the local absolutesag and the local mesh edge length.

Chord Deviation = (local absolute sag value) / (local mesh edge lengthvalue)

Maximum Element Size: Maximum element size defines the value for themaximum length of the local mesh edge.

TIP: Always mesh with the default first! The mesh size can always be made smaller if necessary. To inspect themesh quality, turn the shading off using the shading icon.

If the mesh generation settings are changed, the green dot beside the Mesh branch will change to red indicatingthat the feature needs to be regenerated (updated).

There are four options that you can choose from to update the Mesh:

1. Select Next:Regenerate from the wizard,



2. Select the Regenerate icon on the Standard toolbar,

3. Select Regenerate from the Project Menu (Project > Regenerate), or

4. Use the keypad shortcut Ctrl+R.

If you find that you are changing the mesh parameters often, you should change the default mesh parameters.To do this, go to Tools > Settings > Process Definition > Mesh Settings. This setting is only available when noproject is open.



3.7 Friction

When the Process Definition workbench branch is created, the Friction branch is automatically generated prior tomesh generation.

Friction is applied to areas where the material is being drawn through a radius in a draw die and it is also used byforming conditions such as Pressure Pad. In incremental analyses, it defines the friction between the tooling andthe blank material.

To change the friction coefficient, double click on Friction in the featuretree under General Data or right-click on Friction and select edit from themenu to open the dialog.



3.8 Forming Process

In the process definition workbench, the forming process is set in the Process Manager table. The setting willinfluence the way the tools interact with the part during forming. You can choose between a Draw Die and a FormDie. The FAST Incremental assumes that a draw die is a three piece tool (punch, die and blankholder), whereasa form die is a two piece tool (only punch and die). This setting also affects the tooling generation (in the toolingworkbench) - if the process is set to Form Die, only a punch and die will be generated (with both tools beingeffectively the same), while if the process is set to Draw Die, the tooling generation system will generate threedistinct surfaces to represent the punch, die and blankholder. In either case, additional surfaces will be generatedwhen pressure pads are used.

3.8.1 Draw Die

If you are forming a part using a draw die (as illustrated below left) you should use the Draw Die forming process.As material passes over the radius on the die, additional strain is added to the part due to the friction betweenthe part and the die and the bending and unbending process.

When the process is set to Draw Die, the die tool will remain fixed and the punch tool will move into it along thepunch direction. The blankholder tool will apply a force in the punch direction, pressing the blank against the diesurface. Pressure pads will apply a pressure on the blank in a direction opposite to the punch direction, therebypressing it onto the punch surface.

Tip: in some cases, you may be simulating a "forming" type operation but want to have three separate parts to thetool set. In this case, the draw die setting will allow you to import three unique tools. When using this approach,pay close attention to the tooling definition and punch direction.

3.8.2 Form Die

If you are forming a part using a Form Die (illustrated below right) you should use the Form Die forming process.This process is typically used in progressive dies and simple flanging operations.

In this type of operation, the blank material is not pulled through a radius; it is simply bent around it.

When the process is set to Form Die, the die tool will remain fixed and the punch tool will move into it along thepunch direction. There is no blankholder tool and pressure pads will apply a pressure on the blank in a directionopposite to the punch direction, thereby pressing it onto the punch surface.



3.9 Punch Direction

To perform an accurate sheet metal formability analysis, FormingSuite requires that the punch direction be de-fined. In the incremental analysis, the die remains stationary and the punch moves. The punch directionshould therefore define the direction of punch movement. The punch direction is also used to generate the tool-ing in the Tool Definition workbench. If the punch direction is defined in the wrong direction, then the toolinggenerated will be incorrect and the forming conditions will not be applied as expected.

Blankholder forces are applied along the press direction, thereby pressing the blankholder against the die. Con-versely, pressure pad forces are applied opposite to the punch direction, thereby pressing the pressure padagainst the punch.

By right clicking on the Punch Direction branch for any operation, you may Edit the punch direction or Show/HideUndercut elements. The Punch Direction dialog box includes three methods to orient the part in the pressdirection.



1. Auto. Click the Auto radio button to automatically orient the part intoan approximate press position based on a mathematical algorithm.

2. Prescribed Orientation. You can prescribe the punch direction inone of three ways.

You can use a user defined die line to indicate the punch di-rection. Click the Straight Line radio button and select the dieline that you would like to use, and press OK in the ProcessDefinition - Punch Direction dialog box.

You can use a user defined surface to indicate the punch di-rection. Click the Normal to Surface radio button and selectthe surface that you would like to use, and press OK in theProcess Definition - Punch Direction dialog box.

You can key in the X, Y and Z components of the press direc-tion relative to FormingSuites axis system under the DirectionVector heading in the Process Definition - Punch Direction di-alog box. Click the Manual radio button to enable this feature.

3. Manual Rotation. Enter a positive angular value in the RotationIncrement field then click the up and down arrows beside X, Y or Zto rotate the press direction around the X, Y, or Z axis system. Thisfeature is only active when the Manual radio is selected.

The Preview Undercut button will highlight mesh elements that have negative draft. This may include someelements on vertical walls due to mesh tolerances. The flip button allows you to reverse the punch direction.



3.10 Blankholder Force

FormingSuite has the ability to simulate the effects of a uniformly distributed blankholder force. Blankholder Force(BHF) is applied slightly differently in the three FTI solvers. For the Coupled Hybrid Inverse solver (CHI) and theMulti-Stage solver, the BHF is modeled as a uniform edge tension to the boundary of the part during simulation(the same as the edge tension process condition); however, in the Incremental solver the BHF is modeled as theactual force on the binder ring of the tooling geometry. In either case, this will lead to additional stretch in themodel and will help reduce wrinkling.

To apply a BHF to your part, select the Blankholder Force option under the Forming Conditions icon.

When you open the Blankholder Force dialog, the outer boundary of the part will automatically be selected andthe only input required is to enter a value for total blankholder force followed by selecting OK to apply this processcondition. You may also use the slider to apply the force. Blankholder Force can only be applied to the entireouter boundary. Only a single blankholder force definition should be applied to any model.



3.11 Draw Beads

The draw bead forming condition is used to simulate the control of material flow into the die cavity using a drawbead or a lock bead. If a draw bead is constructed out of a number of draw bead sets with different properties,the last part of a set and the first point of the next set should be coincident. If they are too far apart, there will bea gap in the draw bead and the material will not be constrained between the two draw bead sets. To apply a drawbead to your part, select the Draw Bead option under the Forming Conditions icon.

To apply a draw bead you will need an existing line on the part (either created in the geometry workbench orimported with the model). Select the line to apply the draw bead to and specify the strain or tension to be applied.

NOTE: When you specify either strain or tension the other will automatically update.



3.12 Pressure Pads

The pressure pad forming condition is used to simulate the effects of a pressure applied to an area of the blankinside the die. This pressure is intended to control the movement of material in the local area. FormingSuite cansimulate this by restraining the movement of the mesh elements in the area under the pad. To apply a pressurepad to your part, select the Pressure Pad option under the Forming Conditions icon.

To apply a pressure pad, select the face(s) to constrain from the part model. The entire surface of the selectedface(s) will be constrained by the simulated pad. After selecting the faces, specify a value for the Pressure or forthe Total Force in the designated text box.

If the surfaces on the part cant be used to define the pad area, you can also create (or import) a closed line onthe geometry and use that line to define the pad area.

NOTE: When you specify either a pressure or a total force the other will automatically update.



3.13 Multiple Forming Cases

FormingSuite allows you to quickly evaluate multiple forming cases to compare the effects of different inputs(material, forming process, tipping, or forming conditions) on the analysis results. Unique tipping positions andforming conditions can be applied to each forming cases.

To apply multiple forming cases simply click on the Part Definition branch in the feature tree and select theProcess Definition workbench icon or select Workbench > Process Definition to insert a second Process Definitionworkbench (case) where all the inputs can be modified and solved independent of the previous Process Definitionworkbench (case).


Chapter 4

Tool Definition Workbench

4.1 Introduction

FAST Incrementals seamless setup environment facilitates automatic blank development and positioning onthe curved binder, automatic extraction and set up of the tooling, as well as running and viewing the detailedsimulation.

FAST Incremental is separated into two workbenches: the Tool Definition workbench, which is used to set up theanalysis; and the Incremental workbench, which is used to view the results.

FormingSuite incorporates a powerful set of innovative tools to dramatically speed up the preparation time andvirtually eliminate the need for multiple incremental runs:

Automatic tool extraction of punch, die, blank holder and pressure pads from the first form geometry. Thisoften eliminates the need to manually prepare tooling geometry in an external CAD environment.

Utilizing the proven blank development capability of FASTFORM Advanced eliminates the guesswork in-volved in blank size calculation, binder wrap and blank positioning. These are calculated in minutes, elimi-nating time consuming iterations.

Tool positioning is completely automated eliminating the need to manually position tools and set the pressstroke.

Boundary conditions are inherited from the FASTFORM Advanced setup, so no redundancy in applyingadditional information.

The LS-Dyna solver from LSTC has proven to be the de-facto standard for metalforming simulation. By optimizingthe mesh and solver parameters, FAST Incremental is able to provide an extremely repeatable and accuratesolution while minimizing solution time.

Limitations of Current Software:

Gravity loads are not considered in setup and hence FAST Incremental is not currently designed to handleBIW parts larger than approximately 0.5m x 1m. For thick parts size is not an issue.

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CHAPTER 4. TOOL DEFINITION WORKBENCH

Automatic binder extraction is limited to fully developable binders and binders represented by a singlesurface.

The double attached (symmetry) function is not supported. It is recommended that the full first form geom-etry be used for incremental analyses.

Only Draw Beads, Blankholder Force, Pressure Pad and Pilot Hole forming conditions are supported in theincremental analysis

4.2 Starting an Incremental Analysis

Since incremental analyses simulate the closing of the die, the blank shape must be provided as an input. Theblank can be imported via the Process Definition workbench or taken from an inverse solution (FASTFORMAdvanced or FASTFORM MultiStage).

If you will be using a blank that has been calculated earlier in the project, create the blank geometry for the modelas described in the previous chapter. If required, use the blank geometry tools to add additional material to theblank boundary and/or select a standard shape cutoff blank.

Once the blank is properly defined, the blank must be meshed using a quad mesh and the tooling geometrymust be defined. These operations are performed in the Tool Definition workbench. To enter the Tool Definition

workbench, select the Tool Definition icon from the Workbench Wizard toolbar (typically located at the top ofthe screen) while the Blank Geometry or Process Definition workbench is active.



4.3 First Form Geometry and Blank Size

If you will be using a blank developed with FASTFORM Advanced or FAST Multistage, the blank will be based onthe geometry imported into the Part Definition workbench. To ensure that the blank size is correct, the importedgeometry should represent the first form geometry.

The first form geometry should represent the required geometry of the part after forming, prior to trimming. Itshould include addendum geometry and a small amount of material on the binder surface (in the case of a drawdie).

Final part geometry may not contain sufficient information to extract die face surfaces and full die face geometrywill result in excessively large blank size.

If the imported geometry has complex boundaries or does not include runoff surfaces, you may have to createthe die surfaces in CAD.

4.4 Prepare Binder Wrap

The blank mesh on the binder can be created by clicking the Next button in the wizard or by selecting the Prepare

Binder Wrap icon within the Tool Definition workbench. The Prepare Binder Wrap function will create a quad(four sided elements) mesh of the blank on the binder (binder wrap) for the incremental analysis. The mesh sizeis automatically determined by the software but can be edited by showing the details of Operation 10 in the ToolDefinition workbench (using the right click menu in the feature tree).



4.5 Define Tools

The Define Tools function gives you the option to automatically generate the tooling for the incremental solution, toimport just the die and generate the other tools or to import all of the tools (punch, die, blankholder and pressurepads) for each operation except blank and trim operations.

4.5.1 Tooling Overview

FAST Incremental employs some basic principles and assumptions when setting up the tools for an incrementalrun. A solid understanding of these principles and assumptions will help you to correctly prepare the tooling forthe analysis.

In the current version of FAST Incremental, only four forming conditions are supported: Blankholder Force, DrawBeads, Pressure Pads and Pilot Holes.

4.5.2 Tool Geometry

For the purposes of this simulation, the tooling geometry should be a surface model representing only the surfacesthat may come in contact with the blank/part. Solid blocks should not be used as tooling geometry. Extra surfacesor additional material will increase solving time without adding additional value to the solution. If extra surfacesare imported, they can be deleted using the surface selection filter and the delete key.



4.5.3 Tool Positioning

The tools and blank are automatically positioned in the initial contact position along the punch direction prior tostarting the solver. At this time, the punch stroke is automatically calculated by measuring the minimum distancefrom the punch to the die along the press axis. When designing tool surfaces for importing into FAST Incremental,care should be taken to ensure that there is some overlap in the press direction to ensure that the punch strokeis correctly evaluated. This is sometimes overlooked when designing flange tooling.

In cases where there is undercut on the part (ex. in a secondary cam type operation), the die will be positionedbehind the first layer of part mesh when measured along the punch direction.

When performing multi-stage analyses, the tooling for all operations must be in the same location. The blankwill not be advanced to another position between operations. When the tooling is positioned prior to starting theanalysis, the die remains fixed while the blank/part, punch and blankholder are moved.

4.5.4 Tooling Contact

FAST Incremental does consider the interaction (contact forces/friction) between the blank and the tooling, how-ever as is common in simulation, it does not consider the contact or interference between tools. For example, ifthe tools are designed such that they may contact each other during the press stroke, the software will not modelthis effect.

4.5.5 Punch Movement

The correct definition of the punch is crucial to producing a good analysis run. Although in a standard press,the punch is typically fixed and the die comes down from above, it is standard practice in simulation to changethe frame of reference such that the punch is the tool that moves. This greatly simplifies tooling positioning andprovides for a more robust analysis. In the process setup, it is vitally important that the punch direction be setcorrectly - the punch should be moving into the die.



4.5.6 Blankholders

The blankholder force is applied using the force specified in the process setup workbench. This force is appliedalong the direction of punch travel and is used to clamp the blank between the blankholder and the die. Careshould be taken to ensure that the blank is not significantly deformed when the blankholder closes against thedie face. Since the blankholder is closed very quickly, any deformation produced during this step may not berepresentative of reality and in some cases will cause the solver to hang or fail. This situation sometimes occurswhen the punch and die are reversed or the forming direction is backwards.

The blankholder condition assumes that no "kiss blocks" are used in the binder setup so the blank will be in fullcontact with the blankholder and die surfaces.

If the process is set to Form Die, no blankholder force will be applied in the incremental analysis.

If no blankholder force condition is applied in the Process Setup workbench, the blankholder tool will not bepassed to the incremental solution and solving may fail or a poor result may occur.

4.5.7 Pressure Pads

In FAST Incremental, pressure pads are handled in a similar manner to blankholder forces except the force ispushing the pressure pad tool in the direction opposite to the press direction, thereby pressing the blank againstthe punch tool. This force is applied very quickly at the beginning of the simulation process and remains active asthe punch is moved up into the die. As such, pressure pads should only be applied to surfaces that are coincidentwith the punch face (the surfaces initially contacting the blank at the beginning of the press stroke).

Since interference between tools is not considered in the solution, it is not necessary to leave a hole in the dieface for the pressure pad.

4.5.8 Pilot Holes

In FAST Incremental, pilot holes are modeled by assigning a fixity condition to the edges of the selected hole inthe blank such that the edge of the hole stays fixed in X and Y throughout the analysis. This means that the holewill not elongate during the simulation, nor will the part rotate around the pin.



4.5.9 Generating Tooling

Draw Dies

If the Draw Die process option is selected in the Process Setup or Process Definition workbench then the binderand pressure pad geometry will be generated. The automatic tooling generation extends the boundaries of theimported geometry until it is larger than the blank to create the die geometry. The punch and blankholder arethen extracted from the die geometry.

Form Dies

If the Form Die option is selected, only a punch and die will be created. The automatic tooling generation willextend the flanges down to the binder and then fillet the intersecting edges to create the form die tool. The punchis then created as a duplicate of this die geometry (it is assumed that there is no blankholder in a form die).

When the automatic tool generation function is used, the die clearance used in the simulation will be ten percentof the material thickness defined in the Part Definition workbench. If you want to use a die clearance other thanmaterial thickness, you must import the tooling geometry with the desired die clearance.



4.5.10 Importing Tooling

Import Die

The Import tooling option is only available from the workbench toolbar icon shown below, which opens the ToolDefinition - Import Die dialog.

After specifying the path to the die geometry, you must also specify the location of the die geometry. You mustdefine the die geometry as top, middle, or bottom. When toggling between the different locations, the image willchange to represent the location specified. The auto-generated punch and blankholder skins will be coincidentto the imported die geometry. The offset will be handled internally by the solver based on the definition for thelocation of skins.

After importing the tooling, if there are any extra surfaces that are not needed, you can delete these surfacesusing the select surfaces filter and the delete key.



Import All

The Import tooling option is only available from the workbench toolbar icon shown below, which opens the ToolDefinition - Import All dialog.

The import tooling dialog organizes all of the required tooling into a table. For each tool in the first column, clicktwice in the second column and then press the button to open the file selection dialog. Select the file containingthe corresponding tool geometry. You must specify a separate iges file for each tool.

After specifying the paths to the required tools, you must also specify the location of the imported geometry. Youmust define the geometry as contact, top, middle, or bottom. When toggling between the different locations, theimage will change to represent the location specified.

The imported geometry should be coincident when defining Top, Middle, or Bottom. The offset will be handledinternally by the solver based on the definition for the location of skins. When defining the location of the skinsas Contact, no additional offset will be added during the solution. This means that the surfaces that you importshould NOT be coincident and should be designed with the desired clearances.

The image shown in the graphics area of the tooling workbench doesnt actually show the positioning of the toolingthat will be used in the solver. The image is only for visualizing the tooling components - not their positioning.

After importing the tooling, if there are any extra surfaces that are not needed, you can delete these surfacesusing the select surfaces filter and the delete key.



4.6 Show Tools

The Show Tools function allows you to visualize the tooling and blank geometry prior to solving.

Select the Show Tools icon to open a new display window. You can select the operation to show at the top of

the window. Select the Show Tools icon to open the Display Manager. Usee the check boxes to choose whichgeometry to display and use the slider to pull the tools apart or move them together.

Note that the position of the tooling in the display area does not represent the position of the tooling that willbe used in the solution. The final tooling positioning is set during the initial phases of the solution.

4.7 Editing the Tool Mesh Parameters

You can edit the tool mesh parameters for a specific tool by right clicking on the tool in the feature tree andselecting Show Details. You can then double click on the Generation Settings entry and edit the mesh parameters.

The default tool mesh parameters can be set in the Tools/Settings/Tool Definition menu in the Meshing Settingsdialog when no project is open.


Chapter 5

Incremental Workbench

5.1 Introduction

The incremental workbench is used exclusively to run the incremental solver and to view the results of the incre-mental analysis.

After setting up the binder wrap and tooling for all operations, select the next button in the wizard or select the

Incremental icon from the Workbench Wizard toolbar to enter the Incremental Workbench. Using the wizardwill automatically guide you to select the template and start the solver.

5.2 Incremental Settings - Templates

After generating or importing the tooling geometry, when you move into the incremental workbench you will berequired to pick a template for each operation. The templates provide optimized setups for incremental solving.The Incremental - Select Template dialog is opened by selecting Define Incremental Settings from the wizard.

The template selection dialog allows you to choose a template that will control the solver parameters that are

59

CHAPTER 5. INCREMENTAL WORKBENCH

used in the solution. These parameters determine how detailed the solution will be an also how long it will take.

The following table summarizes the differences in the default templates:

Template Name Purpose AssumptionsFast For faster, but less detailed solu-

tionsUses a simpler element definitionand a large time step to produce afast solution

General For general purpose analyses Smaller time step and more meshrefinement than the fast settingbut still optimized for a faster so-lution

Detailed For detailed analyses on sensitiveparts or for final verification

More advanced element defini-tion, smaller time step and moremesh refinement produce a de-tailed solution



5.3 Solving

FAST Incremental utilizes the proven LS-Dyna solver from Livermore Software Technology Corporation (LSTC).The solver must be installed separately and requires a separate license from the normal FormingSuite license.

Prior to starting the solver, the software automatically positions the tooling in the start position for analysis.

The solver may take only a few minutes for simple models, however larger or more complex geometry may takeseveral hours to solve. FAST Incremental will automatically read the read the result for each step of the solution assoon as it becomes available. The display in the graphics area will update to reflect the latest available solution.At any time during the solution, you can view the result for one of the available result steps by selecting the resultsicon.

If the solver does not generate a complete solution, check the following:

Ensure that the LS-Dyna license is properly configured. Check that the system environment variables pointto the solver and license file, the license is in the correct location and not expired.

When simulating a draw die process, verify that a blankholder force was applied in the Process Setupworkbench

Ensure that the punch directions have been correctly specified

If any results steps are complete, check to ensure that the deformation is occurring as expected



5.4 Results

FormingSuite provides a comprehensive set of result interpretation tools such as graphical displays of safetyzones, forming zones, major and minor strains, thinning and the Forming Limit Diagram.

All incremental results will have multiple incremental steps available to view for each forming operation. To togglebetween the steps, select a step from the drop-down menu on top of the results viewer window and either usethe roll button on your mouse or the up-down arrows on the keyboard.



5.4.1 Safety Zone

The safety zone plot shows whether or not a part will be formable. It is qualitative (shows trends, not numbers).Each color represents a different zone. The zones are described in the table below.

Figure 5.1: Safety Zones and the FLD

Color Zone DescriptionLow Strain Minimal Major and Minor strain, located at the inter-

section of the two axesStrong Wrinkling Tendency High compressive forces producing a strong ten-

dency to wrinkle, most evident in thin materialsWrinkling Tendency Compressive forces sufficient to cause thickening

of the part and minor wrinklingSafe Is the area between the shear margin on the left

and the thinning limit on the right, and below theFLC safety offset. This area will not likely experi-ence failure during forming

Marginal The area between the safe and fail zones. Thisarea provides a buffer for process and material vari-ability. The safety offset is usually 10% for steelsand 6-8% for aluminums

Fail Any area to the left of the shear limit, above the FLCand to the right of the thinning limit. This area mayexperience localized thinning or necking, failure



5.4.2 Forming Zones

The Forming Zone plot describes the state of stretch in the part. It is a qualitative plot and each color representsa different zone. Each zone produces a different panel quality and characteristic. The forming zones can be usedto identify the strain state of the panel. The zones are described in the table below.

Figure 5.2: Forming Zones and the FLD

Color Zone DescriptionLow Strain Minimal Major and Minor strain, located at the inter-

section of the two axes.Strong Wrinkling Tendency High compressive forces producing a strong ten-

dency to wrinkle, most evident in thin materials.Wrinkling Tendency Compressive forces sufficient to cause thickening

of the part and minor wrinkling.Loose Material Material in tension in one direction and compres-

sion in the other causing a loose effect. Area maynot be stiff and some minor wrinkling or wavinessmay be present.

Semi-Tight Panel Minor strain is negative bi-direction tension is stillpresent within the area. This result is in similarcharacteristics as a tight panel.

Plain Strain Stretch in only one direction with no change in thetransverse direction. Thin sliver area around theMajor strain axis.

Tight Panel Stretch in two directions resulting in good strengthand dent resistance characteristics. These at-tributes are desirable for visible or show surfaces.Using an addendum to increase draw depth oftenincreases the size and distribution of the zone.


CHAPTER 5. INCREMENTAL WORKBENC

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