We only assign an item to the assembly of a weld arrangement and not its parts. When the status of the item is set to "in review" or "released" the assembly is locked to read only while its parts are not locked and can be edited. Vault should also lock the unassigned children of locked assemblies. I do not want to assign items to the parts of a weld assembly because they can not be ordered separately. If I assign items to all parts I end up with a database of items where 95% is never used.