Purpose:
In this example we will do a strength analysis on sheet metal part. The bracket shown below is used in assembly to connect two subassembly components through fastener systems. Our purpose in the demonstration is to show how to use FEMAP Express to do the analysis.

Prerequisites:

An active Solid Edge Classic license.

Step 0: Open the existing sheet metal part
Open the Solid Edge sheet metal document.

Step 1: Create a mid surface (Sheet metal parts only)
Sheet metal parts differ from other parts in that the part consists on thin areas of material. According using a 3D mesh will give inaccurate results and we use surface meshing for sheet metal parts.

We use the mid surface tool to create a surface that we can use for the meshing. After opening the part in the Solid Edge sheet metal environment, click on the Home tab. In the sheet metal command group on the Home tab, select Mid Surface.

Use the mid surface toolbar to select the side of the face from which the mid surface should be derived. Also select an offset ratio (which determines how deep the surfaces should lie in the part) – 0.5 is acceptable.

Click on Preview and on Finish. A new step item will now appear in your feature tree. By hiding all other features and showing the mid surface only we have the following:

Step 2: Create sketches for force and pressure directions (Optional)
You may need to create sketches that you can use to indicate the direction of forces. This is only necessary if the forces are:

• not perpinduclar to any surface,

• not parallel to edges of the examined part,

• and not parallel to edges of other parts (when the examined part is open in the context of an assembly).

We have already created a sketch in the demo file that indicates the direction of the force that will be applied to the part.

Step 3: Use FEMAP Express
On the Tools tab select FEMAP Express.

3.1 Type of Analysis: We are prompted to select a mid surface and select the mid surface we created in step 1 by clicking on the surface. The drop down box also prompts us to choose between modal and stress analysis. We select stress analysis and click on the green accept button.

3.2 Material Selection: Now are now prompted to assign a material type to the part. (When we created the demo part we set the gauge of the sheet metal part to 16 gauge.) In this example, select “Stainless Steel 304” from the drop down list. You can also use the Material button to open the material library and to change the gauge of the part.

3.3 Load definition: A new load definition window opens which can be used to define multiple loads.

Click on Add Load. Enter a name for the new load (e.g. DemoLoad1). Set the load to force or pressure - we will use force. We are designing the bracket to with stand 5kg, hence we set the load value to 50N. We select the inner edge of the hole (on the mid surface) as the item to which the load will apply. Click on Next.

We now choose Line as the direction reference and select the line in the sketch (of step 2). We could have selected an edge of the part or use Face to define the direction of the force. Use the Flip direction check box to change the direction if necessary. Click Next.

We have the option of adding additional loads. In this demo we one have one force and select Finish.

3.4 Constraint definition: The constrained faces on the modal must now be defined. We select the face with slots as the constrained face and press the green accept button.

3.5 Examine the results:
FEMAP Express will now automatically mesh and solve the loads and constraints. FEMAP Express can show:
•    the displacements of each element
•    the stresses at each node
•    and the safe factor across the part.

Solid Edge can also animate the displayment and stresses in the part.

Tips:
1.    You can change the meshing resolution
2.    Multiple loads and constraints can be added
3.    The material properties can be changed from the side menu
4.    Remember that at rounds and hole edges one will get higher than expected stresses – this is often the result of meshing. Setting the mesh resolution finer reduces the calculated stresses.

Information:
This demo was created by JD Marx for ESTEQ PLM and remains the copy right of ESTEQ PLM
The original part file can be obtained from www.solidedge.co.za
The demo was done on Solid Edge ST