Additional Capabilities > Manufacturing Process Management > Transforming an eBOM into an mBOM > Creating an mBOM > Overview of Generate Downstream Structure Action > Use Cases: Generate Downstream Structure > Use Case 2: Generate a Downstream Structure Based on the Part Usage Attribute
  
Use Case 2: Generate a Downstream Structure Based on the Part Usage Attribute
Consider that the following structure is present in the BOM Transformer:
• An equivalent link exists between Upstream Parent Part (Design) and Downstream Parent Part (Manufacturing).
• All the parts in the structure have the part type as wt.part.WTPart.
1. Access the associativity.properties.xconf file located in Windchill/codebase/com/ptc/core/foundation/associativity.
2. Add the following restructuring rules:
Property name="com.ptc.windchill.associativity.reconciliation.addusage.wt.part.WTPartUsageLink" multivalued="," default=""/>
<AddToProperty name="com.ptc.windchill.associativity.reconciliation.addusage.wt.part.WTPartUsageLink" value="targetType=wt.part.WTPart"/>
<AddToProperty name="com.ptc.windchill.associativity.reconciliation.addusage.wt.part.WTPartUsageLink" value="transformoption=newPart"/>
<AddToProperty name="com.ptc.windchill.associativity.reconciliation.addusage.wt.part.WTPartUsageLink" value="attributeMapping.rule1=AttributeNum1:10:AttributeNum2:10"/>
In case of properties that involve mapping, the mapping attributes specified for upstream and downstream must not be the same.
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After you initiate the action on the selected part in the upstream, the Windchill system traverses the structure below the selected part. This configuration ensures that :
• If the Windchill system detects a part with the part usage attribute AttributeNum1 set to 10, then the detected part is added in the downstream as a new part, under the part whose part type is wt.part.WTPart and the part usage attribute AttributeNum2 value is set to 10.
3. Select the Upstream Parent Part (Design) and click in the middle pane tool bar.
4. The following structure appears in the BOM Transformer:
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Part C1 (Manufacturing) and Part C2 (Manufacturing) are added as new parts under Part T1 (Manufacturing). This is because, Part T1 (Manufacturing) satisfies the criteria set in the properties.