• Importing the entire product structure is not required. Each row in the product structure represents a distinct action. For example, to add a part to an existing structure, simply identify the parent assembly and include a row with the new part.

• When a component part appears at multiple levels within a structure, the spreadsheet import must consistently reuse the same child parts for that component across all levels. If the spreadsheet defines different child parts for the same component at different levels, the child parts from the first occurrence is applied throughout.

• When importing a product structure, a new baseline is generated for each worksheet.

◦ You must have Create permission for the ManagedBaseline type.

◦ If a baseline name is provided, it is used as a prefix. Otherwise, the system assigns a name using the format:

• Imported product structures must reference parts that either already exist in Windchill PDMLink or are created within the Part worksheet of the same workbook. If the referenced part is missing, the import fails.

• When a modified product structure is imported, any existing product structure links that are not included in the spreadsheet remain unchanged.

• When creating a new product structure, each worksheet row represents an Add action. In contrast, when modifying an existing product structure, each row may represent an Add, Replace, or Delete action.

• To ensure valid usage during product structure import, the quantity, usage unit of measure, and reference designator must be consistently aligned. If any of these values are mismatched, errors may occur, whether for newly defined usages or updates to existing ones.

• To modify a quantity within a product structure, use the Add action and specify the updated quantity. The Delete action removes the part and all associated quantities from the structure, but does not delete the part from Windchill. Alternatively, the Replace action can be used to substitute a child part on an existing usage link during BOM sheet import.

• When a child part is replaced with its substitute, the original part becomes the substitute for the new one. If the Part Management preference Enable quantity and reference designators for substitute parts is enabled, the attributes defined in the substitute configuration populates any blank quantity and reference designator fields in the spreadsheet. Any non-blank values in these fields are treated as modifications resulting from the Replace action.

• The Replace action updates the child part in the product structure. The corresponding worksheet row reflects the attributes and, if applicable, the structure of the new part being introduced.

• While importing a product structure, reference designators can be included in the spreadsheet under the Reference Designators column. If the number of reference designator entries exceeds the quantity specified in the Quantity column for the usage unit of measure Each, an error occurs.

• When importing a modified product structure, existing unnamed occurrences remain unaffected as long as the total number of occurrences does not exceed the specified quantity.

• When reusing a line number or reference designator across child parts of the same parent, you must first either remove the original child parts or clear their existing values. Only then can you modify the desired line number or reference designator, or add different child parts using an importable spreadsheet.