Integration with Other Applications > Managing CAD and Part Structures in Windchill > Top-down Design > Building the CAD Structure from the Part Structure > Updating CAD Document Usage Links
  
Updating CAD Document Usage Links
You can modify the value of the Line Number and/or Find Number attributes on a Windchill part’s usage link by inserting or editing the number in the Uses tab located on the part’s information page as shown in the following figure. The Line Number represents the manufacturing BOM line number where the part is listed. The Find Number represents the location of the part within the assembly drawing.
If you modify these attributes and then use the Windchill part to build a corresponding CAD structure, you can choose to update the same attributes on the CAD document usage link during the build process.
Preferences
To enable this behavior, you must set the following preferences on the Windchill server before performing the build process.
• EPM Service Preferences > Build Service Preferences > Line Number Attribute = Internal name of IBA of category Integer
• EPM Service Preferences > Build Service Preferences > Find Number Attribute = Internal name of IBA of category String or Integer
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• This behavior is only supported for CAD documents created using CATIA V5, NX, and PTC Creo (versions 2 and greater).
• With PTC Creo, updating only the line/find number attributes occurs without marking the assembly as modified.