Structuring BOM

• To create a functional location BOM or equipment BOM, you can use material BOMs, equipment BOMs, and functional location BOMs as a template.
• To create a material BOM, you can only use material BOMs as a template.

A BOM can be linked with a technical object in two ways: direct assignment and indirect assignment.

For direct assignment, a BOM is created directly for the object (functional location or equipment).

For indirect assignment, you can assign a BOM to master records for technical objects using a material master record. Create the assignment in the master record for the technical object by entering the material number in the Construction type field. The BOM is dependent on the material, not on the technical object. Indirect assignment is advisable if several objects exist for the same construction types. You do not have to create an equipment BOM for each individual object – all objects of the same construction type use the same material BOM.

The data that you maintain in the BOM header is valid for the entire BOM with its components (BOM items or sub-items).

The components of a technical object are located in the BOM items. Item data is only valid for a particular item within the BOM.

In each company, BOM usage (in the Customizing for Production) defines the allowed entries for the item status. Various BOM item indicators are combined under the heading "item status", and they include relevant indicators for engineering/design, production, costing, and so on.

The item status indicators control the process flow in subsequent areas of work and the selection of items in the BOM explosion. They require, enable, or exclude processing in these areas. If processing is supported in an enterprise area, you can maintain area-specific data for the items. For example, only items relevant for production are copied to the production order.

To maintain structure elements or items relevant for maintenance for a functional location BOM or equipment BOM, you must select a BOM usage that supports items relevant for maintenance. BOM maintenance for the different areas (for example, engineering/design, production) is performed separately for each usage. If you create several BOM with different uses for one material, the system saves the BOM for each usage with their own internal number.

Assemblies act as structure nodes within a BOM and combine spare parts relevant for maintenance.

Maintenance assemblies are materials of material type IBAU. The material master record only contains basic data and classification data, so inventory management is not possible for maintenance assemblies.

Use maintenance assemblies as structure elements in a BOM if you want to complete either of the following tasks:

• Combine similar materials under one node.

• Track the costs in the Plant Maintenance Information System, but do not require inventory management.

However, you also have the option of selecting a material of another material type as a maintenance assembly.

The Maintenance Assembly Indicator is set on the Status/Long Text of the BOM items screen and can only be maintained for items relevant for maintenance. During the processing of maintenance tasks, items marked as a maintenance assembly are displayed as structure elements of an operational system. They can be used to describe an item from an operational system in greater detail (for example, possible location of damage).

• Stock item (L) – Motor
• PM structure element (I) – Shaft assembly
• PM structure element (I) – Control electronics

These items have their own BOM that contains the maintenance-relevant individual parts.

This overall BOM indicates that the complete motor is available in stock as a spare part. Coal brushes and electric mains are also inventory-managed as spare parts, while the casing is managed by external procurement.

The shaft casing assembly and control electronics are not inventory-managed as complete parts. You can represent the pump PM structure elements, which provide a clear overview of the overall structure, in the BOM. The shaft casing assembly and control electronics are inventory-managed and can be reserved for maintenance tasks.

A BOM can manage data that is obligatory for plant maintenance at the technical object location. The result is spatial validity – the plant. This consists of the workplaces, at which all of the necessary preparatory work is organized (for example, materials planned and task lists created). In this case, you can create a plant-specific BOM. Numerous checks are made. In the case of a material BOM, for example, a material master record with plant data for the relevant plant must exist for the material in the BOM header. When items are entered, the system checks whether plant data is also available for the material components. If the results of the checks are satisfactory, the system copies the material to the material BOM.

However, you can also create a BOM without reference to a plant; this is called a group BOM. A group BOM can be used, for example, if the engineer maintains a BOM in the design phase that is then assigned to one or more plants for Production. The system merely checks whether material master records are available. The plant-specific material checks are not performed.