Managing part BOMs

Understanding part BOMs

To create a part BOM, you must first create a preliminary part BOM. Once the preliminary BOM parts and subassemblies are created and linked to the design BOM, you must align the design BOM with the part BOM. Part BOM part geometry and position are determined by design BOM geometry. To support situations in which you need 3D geometry and others in which you need only subassembly metadata, two types of alignment are available.

A heavy alignment carries 3D data from the design BOM into the part BOM, generates an end item, and sets each part's unique ID in Context (IDIC) to the same value as that of the design BOM. It also aligns BOM line properties; in other words, BOM line attributes that are represented as column values in the part BOM and the design BOM views. An end item icon is displayed on the heavily aligned item to indicate that any part BOM children are hidden. The design BOM line is copied as a child to the part BOM line and each line is highlighted in green, indicating that a precise BOM View Revision (BVR) has been set and that two levels of alignment have been applied: revision and occurrence. If the Design Assignment State column is visible in the part BOM, it displays a value of 2 to indicate a heavy alignment. A BVR precisely defines which revision the part BOM is using.
A light alignment also aligns BOM line properties but does not appear as an end item and does not carry over 3D geometry. Use light alignments to align the parent of a design BOM subassembly to the parent of a companion part BOM subassembly. This is useful when the children of the design BOM subassembly need to be treated individually. You can then run heavy alignment on child nodes in that subassembly that need to be treated individually and retrieve 3D data for those nodes. If the Assignment Level column is visible, it displays a value of 1 to indicate a light alignment.

Design BOM	Part BOM	MBOM

design BOM design object Part Manufacturing part/assembly Precise End Item
(1) Heavy alignment includes both an occurrence and revision alignment, both of which are interrelated. An individual design BOM revision can be related to many part revisions, while an individual part revision can be related to 0 or 1 design revisions. Heavy alignment: Applies an end item to the part BOM line, which hides all children of a subassembly. Brings 3D geometry to the part BOM. Treats a subassembly as a single part. If parts in a subassembly need to be accessed in multiple locations downstream, subassemblies should use light alignment on the subassembly and then apply heavy alignment to those parts. (2) Light alignment applies only occurrence alignment (part properties) but retains all children. Light alignment does not bring 3D geometry to the part BOM. (3) When applied from the part BOM to the MBOM, a heavy-aligned part can be assigned to an outsourced (buy) part. (4) A heavy-aligned part can also be assigned to the MBOM as an internally manufactured (make) part. (6) A light-aligned manufacturing assembly can be assigned to the MBOM as a collection of heavy-aligned parts, each of which is internally manufactured and assembled.	(1)	Heavy alignment includes both an occurrence and revision alignment, both of which are interrelated. An individual design BOM revision can be related to many part revisions, while an individual part revision can be related to 0 or 1 design revisions. Heavy alignment: Applies an end item to the part BOM line, which hides all children of a subassembly. Brings 3D geometry to the part BOM. Treats a subassembly as a single part. If parts in a subassembly need to be accessed in multiple locations downstream, subassemblies should use light alignment on the subassembly and then apply heavy alignment to those parts.	(2)	Light alignment applies only occurrence alignment (part properties) but retains all children. Light alignment does not bring 3D geometry to the part BOM.	(3)	When applied from the part BOM to the MBOM, a heavy-aligned part can be assigned to an outsourced (buy) part.	(4)	A heavy-aligned part can also be assigned to the MBOM as an internally manufactured (make) part.	(6)	A light-aligned manufacturing assembly can be assigned to the MBOM as a collection of heavy-aligned parts, each of which is internally manufactured and assembled.
(1)	Heavy alignment includes both an occurrence and revision alignment, both of which are interrelated. An individual design BOM revision can be related to many part revisions, while an individual part revision can be related to 0 or 1 design revisions. Heavy alignment: Applies an end item to the part BOM line, which hides all children of a subassembly. Brings 3D geometry to the part BOM. Treats a subassembly as a single part. If parts in a subassembly need to be accessed in multiple locations downstream, subassemblies should use light alignment on the subassembly and then apply heavy alignment to those parts.

(2)	Light alignment applies only occurrence alignment (part properties) but retains all children. Light alignment does not bring 3D geometry to the part BOM.

(3)	When applied from the part BOM to the MBOM, a heavy-aligned part can be assigned to an outsourced (buy) part.

(4)	A heavy-aligned part can also be assigned to the MBOM as an internally manufactured (make) part.

(6)	A light-aligned manufacturing assembly can be assigned to the MBOM as a collection of heavy-aligned parts, each of which is internally manufactured and assembled.

When you create a standard EBOM from a design BOM in Manufacturing Process Planner, the EBOM links to the parts in the EBOM. When you create a part BOM from a design BOM, the parts are not linked but are instead copied to the part BOM.