Often because of handling reasons it makes sense to create phantom assemblies by grouping items within the 3D structure that are not relevant to the bill of material. In keytech PLM those assemblies are not considered for the bills of material creation in the normal way but their components are inserted at the nearest upper level with the correct quantities.
The 3D model can be built up by the engineer in terms of optimal handling without losing the relationship of the CAD model to the bill of material and to the ERP system.
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