
General Information
Validity
Special Topics
Finding Data
A material BOM is a complete list of the components that make up a particular finished or semi-finished product. In addition to the material components, which you can identify by material numbers, a material BOM can include the following items:
Documents, such as drawings, programs, or pictures (identified by a document info record)
Text items, which you use to store information, for example, for internal purposes
You can only create a material BOM for a material if a material master exists for the material.
A material BOM consists of a header and the individual items. The header contains data that applies to the entire material BOM, such as the BOM status or administrative data. In particular, the header contains the material to which the material BOM applies. Each item represents either a material component, a document, or a text.
Note that the SAP material BOM is a single-level structure. You build up multilevel material BOMs implicitly by including a component for which a material BOM is also available in the system. In the material BOM, such a component is called an "assembly". An assembly is a group of parts that are assembled together and form either a finished product or a component of a finished product.
You can create a material BOM with or without reference to a specific plant. You need a plant-specific material BOM for plant-specific processes, such as MRP, creation of production orders, or procurement of components. A material BOM without reference to a plant, which is called a "group BOM", is valid across the entire company and mainly relevant for the design phase of a product.
Note
Only in the back-end system can you extend the area of validity that was defined when a material BOM was created. You can allocate a material BOM created in a specific plant (such as 0001) to additional plants (such as 0002 and 0003) or to the entire group (no plant). After the design phase, you can also allocate a group material BOM to individual plants for production.
You can maintain separate BOMs for different areas within your company, such as design or production. In this way, each area is only dealing with the specific data it requires. You can also create just one universal BOM for all areas within your company. You select the area for which a BOM is valid in the BOM Usage field. The BOM usage also determines which item statuses you can set for an item, such as relevant to engineering, relevant to production, relevant to costing, and so on.
Components or component quantities in an assembly may vary according to the quantity to be produced or procured (the lot size). If you want to use different BOMs for different lot sizes, you create alternative BOMs and enter a lot-size range for each alternative. The alternative selection for the dependent requirements can take place using the lot size. During the planning run, the system finds the alternative that matches the lot size in the planned order and uses this alternative to determine dependent requirements.
In general, a material BOM or a material BOM item is only relevant for a certain validity period. The validity period is delimited by a valid-from date and the valid-to date in the BOM header and BOM item. The date on which you create a BOM is the date on which this BOM becomes effective. If you create or change a BOM using a change number, the system takes the valid-from date from the change master record. The system default for the valid-to date is December 31, 9999. If you change a BOM using a change number, the system determines the valid-to date dynamically. If you change a BOM using a change number with a valid-from date, the pre-change validity period of the BOM header or BOM item ends at exactly 00.00 hours on this valid-from date.
A recursive material BOM is a material BOM that contains the material itself as an item. If you want to create a recursive material BOM, you must select the Recursiveness Allowed checkbox in the material BOM header.
On the Header tab page, choose the Material Data tab page.