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Creating and Changing BOMs/Group BOMs
The following lists assumptions related to creating and changing BOMs/Group BOMs:
The material master that is the header of the BOM/Group BOM exists in SAP before the BOM/Group BOM is created.
Both engineering and production BOMs/Group BOMs are sent to SAP from Windchill PDMLink. Windchill ESI uses the contents of a cross-referencing file to determine whether to send a given BOM as an engineering BOM as a production BOM.
Parts or documents associated to parts or BOMs/Group BOMs or assembly BOMs/Group BOMs can be created or changed during the action of changing or creating a BOM/Group BOM.
Reference designators and alternate parts are supported by Windchill ESI but are not supported by SAP. Alternate parts are published to SAP as simple parts, with no relevant links.
At a minimum, the children associated to the BOM or Group BOM (parts, BOMs, Group BOMs) must exist in the same distribution targets as the parent. These children may exist in zero or more plants. When creating a BOM, if the children do not exist in the same distribution targets, SAP returns a failure message, and processing of the BOM stops. When changing a BOM, if the children do not exist in the same distribution targets, SAP returns a functional warning message, but continues processing.
If the children on a BOM/Group BOM are CN-centric, the BOM/Group BOM is also CN-centric. Likewise, if the children on a BOM/Group BOM are not CN-centric, the BOM/Group BOM is not CN-centric.
Alternate Item Group Number is passed fromWindchill PDMLink to the EAI components when adding or deleting substitutes on a BOM. If the Alternate Item Group Number is not passed when deleting substitutes, the substitute is deleted anyway.
For multi-level BOMs/Group BOMs, it is not necessary that the sub-assemblies exist in SAP. It is necessary that the part (that will become the sub-assembly) exists (it must be created before it can be added to the Group BOM).
Plant information is sent over when creating and changing BOMs. If no plant information is sent over, a Group BOM is created, and SAP returns a functional warning message to inform you that a Group BOM has been created. SAP does not return a functional warning message when changing Group BOMs.
BOM headers in SAP are related to material master records. If a BOM is created with a revision, the related material master must be modified accordingly. If the revision of the BOM changes, the revision of the related material master is modified accordingly. BOM releases or revision changes for BOMs from Windchill PDMLink are always accompanied by a corresponding material master (part) record or a revision change for the record respectively.
BOM releases from Windchill PDMLink are always accompanied by a corresponding material master (part) record.
The SAP RFC function module BAPI_MATERIAL_BOM_GROUP_CREATE is used to create BOMs/Group BOMs. CSAP_MAT_BOM_MAINTAIN is used to change BOMs/Group BOMs.
Line numbers are supported but not required. If an incorrect line number is sent when attempting to change or delete a component on a BOM, SAP returns a functional warning message, the component is not changed or deleted, and processing continues.
The API used to create BOMs/Group BOMs can be used for BOMs/Group BOMs with both line numbers and without line numbers.
Effectivity dates are supported at the component and BOM/Group BOM header levels independently.
Only material (stock item) components are created on BOMs/Group BOMs in SAP. Text items and documents as components on BOMs/Group BOMs are not supported.
If the component line number is not passed from Windchill PDMLink, SAP automatically assigns line numbers.
For any instance of Windchill ESI, all BOMs/Group BOMs are published either with line numbers or without line numbers. Any one implementation of Windchill ESI does not publish a BOM/Group BOM with line numbers as well as a BOM/Group BOM without line numbers.
Different views of a part are not associated to the same plant where they differ. Different views of the same part are not passed to SAP on the same change master.
Windchill PDMLink sends the first character of a view version to the Windchill ESI EAI Components. The EAI components do not filter view versions. Alternatively, with a certain Windchill ESI preference turned on,Windchill PDMLink sends the revision of the associated ERPMaterial object to the EAI components.
Views are used inWindchill PDMLink to represent different functions of the same BOM.
If a part is associated to an existing BOM in SAP, the unit of measure of that particular part cannot be changed.
One call to a CSAP remotely-enabled API function module can create, change, or delete multiple parent/child relationships. Multiple CSAP calls are necessary to change or create the same BOM/Group BOM in multiple organizations.
When creating a BOM that is published with a CN (CN-centric) in an SAP distribution target, SAP returns a functional warning and processing continues. You see the warning message in the BusinessWorks engine log because SAP throws a warning when BOMs are created with a future effectivity date. When a CN is initially created, it has a future date of 3001-12-30 assigned. When the BOM is first created, it is assigned this future date as its effectivity date (thus, a warning is seen in the engine log). Once processing of all objects on the CN is successfully completed, the CN is then updated with the appropriate effectivity dates for all objects. When changing a BOM in SAP that is published with a CN (CN-Centric), SAP does not return a functional warning.