Additional Windchill Capabilities > Manufacturing Process Management > Transforming an eBOM into an mBOM > Implicit Replacement of Parts
  
Implicit Replacement of Parts
An existing BOM variant is used as reference when creating a new BOM. You can configure the application to replace parts implicitly when you create a BOM variant. During the creation of a BOM variant, whether parts should be replaced implicitly is determined by the value set for the Implicit Replacement of Parts in Downstream for Replaced Part in Upstream preference. By default, the preference is set to No, in which case only a new BOM variant is created. There is no implicit replacement of parts.
When the preference is set to Yes, the selected part in downstream is replaced, as follows:
A replaced upstream part, if an equivalent downstream part does not exist for the replaced upstream part.
An equivalent downstream part, if the replaced upstream part has an existing equivalent downstream part. A warning message appears if multiple downstream equivalent parts exist for the replaced upstream part.
If there are parts that are replaced in the upstream BOM, the new BOM variant propagates those changes in the downstream BOM.
The New Downstream Part Variant and New Downstream Branch Variant actions, available in the middle toolbar, perform implicit replacement only when the Implicit Replacement of Parts in Downstream for Replaced Part in Upstream preference is set to Yes.
During the execution of implicit replacement, the following entities are retained:
The equivalent link between the upstream and downstream parts.
The positioning of the occurrences, if exists.