Tips & Tricks - Weld Analysis Tools
|SolidWorks 2010 comes with a new edge weld tool which helps designers size their welds straight from an analysis. Here is a simple example showing how the tool works and how to interpret the results:
A thin walled tube is welded to a mounting plate.
|By creating a shell model of the setup and using the Edge Weld Connector between surfaces, a plot of the weld size was obtained through a simple linear analysis:|
|Shigley’s well recognized “weld as line” sizing technique was used to verify the weld size by hand and can be viewed here. This method revealed for a 1kN force that an 11.2mm weld would be needed (with an 7.9mm throat thickness).|
|Those familiar with FEA will realize that this connection between the pipe and wall will actually introduce a singularity into the analysis, meaning the maximum stress will never converge no matter how small the mesh used. Decreasing the mesh size around the connection and in turn increasing the maximum stress toward infinity has no effect on the weld size. The weld tool uses nodal forces rather than stresses and therefore is unaffected by this type of singularity.|
For complex problems where the stresses are difficult to derive accurately, there are a number of approximate methods available to the advanced analyst - give Greg a call on 03 382 5282 or email him to discuss further training or analysis options.