Assembly Welds

To cost assembly welding, aPriori requires that each weld be defined in one of two ways:

For more information, see the Weld GCDs section of the aPriori User Guide.

This section has the following subsections:

Pro Welds

You can edit a virtual or Pro weld by right-clicking the Weld GCD (in the Manufacturing Process or Geometric Cost Drivers pane) and selecting Edit Operation. The Welding dialog is displayed in the lower right-hand pane of the Operation Sequence dialog. For more information, see the Weld GCDs section of the aPriori Professional User Guide.

In starting point Digital Factories, if aPriori is unable to obtain the width of a Pro weld from the values specified in the CAD model, it attempts to estimate the width in one of the following ways:

  • Estimate the width from the actual as-modeled surface weld geometry (for "surface-type" welds). Administrators can disable this behavior by setting the site variable deriveProWeldWidthFromGeometry to false.

  • Estimates the width based on the weld depth. Administrators can disable this behavior by setting the site variable deriveProWeldWidthFromDepth to false.

If aPriori is unable to obtain the width of a Pro weld from the values specified in the CAD model, and it uses neither of the above estimation methods, the width is set to 0.

aPriori sets to 0 width and depth values that it is unable to obtain or estimate. Welds with 0-valued width or depth have 0 volume and 0 cross-sectional area. In starting point Digital Factories, such welds fail to cost. To address missing dimension values, users can either update the Creo model parameters in Creo, or override the weld properties in aPriori.

Administrators can direct aPriori to cost 0-cross-sectional-area welds instead of failing them, by setting the cost model variable failWeldsWithZeroCrossSectionArea to false. Note that in this case, many components of cycle time are 0, but overall cycle time is not 0, since it includes components that are independent of weld dimensions.

Virtual Welds

To cost welds that have not been defined in the CAD model, aPriori allows users to create virtual welds. Once created, these virtual welds can be copied into other assemblies with substantially similar geometry (such as an assembly that has been created due to a modification or part number change. When defining a weld as a virtual weld:

  • A weld created in aPriori is associated with a reference or set of references (edges or datum curves) in the CAD model. By default, the total length of the weld is determined from the reference length. In this case, the total length is dynamic; if the CAD model reference length changes, so will the total length of the weld. You can also override the total length of the weld and specify a different value. In this case, the total length is not dynamic.

  • You can specify the type of weld (for example, fillet or square groove) and the production mechanism (that is, manual or robotic).

  • In most cases (except for spot welds), you can specify the weld width and depth.

  • You can also specify whether the weld is intermittent or continuous. If the weld is intermittent, you can specify the segment length and the pitch. The number of segments is computed based on the total length, pitch, and segment length.

You work with virtual welds through the Component Viewer. For more information about how to create, copy, edit, and delete virtual welds, see Using the Component Viewer tools and commands in the User Guide chapter Using aPriori Desktop.