Manage Tolerances and Surface Roughness

You can use aP Design to import and edit tolerances and surface roughness specifications, and understand how those specifications affect manufacturability and cost.

Import and Edit Requirements

aP Design can analyze tolerance and surface roughness requirements that are:

• Included as semantic production and manufacturing information (PMI) in a CAD model that you upload to aP Design.

• Manually added to or edited for a scenario in aP Design.

• Included in a scenario that is published from aP Pro (via AppStream™).

You can also review and work with threading - see Examine Threading Results.

Optimize Requirements

Tolerance and surface roughness requirements can impact both the required cycle time and the choice of processes for processing Geometric Cost Drivers (GCDs). Tighter tolerances may increase part manufacturing costs as they typically require longer cycle times, more precise tools, and more skilled labor. Looser tolerances may decrease part manufacturing costs, but increase assembly or rework costs if the parts that they yield are hard or impossible to assemble.

Example

Consider a real-world case where the cost of a part cannot be determined because the machine that has been selected to make a part cannot meet the specified tolerance requirements. In aP Design, the part fails to analyze, and the design guidance indicates that the tolerance is too tight for the selected process. You can update the tolerances in your CAD model, and then overwrite the component in the scenario with the updated CAD file.

If you then re-analyze the part and aP Design determines that the part is now manufacturable but would be even easier to make if the tolerance were looser, the design guidance suggests a value for a looser tolerance requirement. You can then further improve manufacturability and lower cost by updating the tolerance requirement to the suggested value.

Topics and Examples