SAP HELP R/3 4.70 extracts: PP-MRP

 Grouping with Hierarchically Structured Grouping WBS Elements 

Use

You use this procedure if you would like to have several grouping criteria, that is, several grouping WBS elements, in a plant to group requirements.

The grouping WBS elements are hierarchically structured in this procedure.

Prerequisites

• You have defined that a material is to be planned using requirements grouping by entering the appropriate MRP group in the material master.
• You have entered a period lot-size, for example, MB for monthly lot size, in the material master.

• You have created several grouping WBS elements and have entered the indicator 2 the grouping WBS element field for them.

If you would like to group the WBS elements according to two criteria, for example, ordering parties from the public sector/ private sector, you create one grouping WBS element for each grouping criterion in the plant.

• You have selected the Valuated stock field in the project definitions of the WBS elements and the grouping WBS elements (tab page Control data).
• You have assigned the MRP groups to every grouping WBS element, for which the grouping WBS element is to be used (see Assigning MRP Groups to a Grouping WBS Element).
• You have assigned the WBS elements, whose material requirements are to be grouped, specifically to one of the grouping WBS elements (see Assigning WBS Elements to a Grouping WBS Element).

• You have assigned the grouping WBS elements at lower levels of the hierarchy to the grouping WBS elements at the higher levels of the hierarchy.

Features

In MRP, a material that is allowed to be planned with requirements grouping is planned:

• with the grouping WBS element that has been assigned to the WBS element, which has caused the material requirement, or
• with the grouping WBS element that is assigned to the dependent requirement (that is determined during the BOM explosion).

Example

You can imagine the material requirements planning of a project in the form of a pyramid. At the top is the finished product that is planned with the individual WBS element.

The lower levels of the hierarchy represent the hierarchy of the grouping WBS elements. Every level simultaneously represents a BOM level. The lowest level represents the lowest BOM level with raw materials that are planned without reference to the grouping WBS elements as collective requirements and are managed in the plant stock.

The following illustration shows the hierarchical structure of grouping WBS elements in a plant. Every grouping WBS element has been created for a particular grouping criterion:

Grouping WBS Elements

The grouping WBS elements 1 to 6 correspond to the following grouping criteria:

• Grouping WBS element 1 corresponds to domestic orders from the government
• Grouping WBS element 2 corresponds to domestic orders from the private sector
• Grouping WBS element 3 corresponds to orders from France
• Grouping WBS element 4 corresponds to grouping of domestic orders
• Grouping WBS element 5 corresponds to grouping of orders from Europe except for domestic orders.
• Grouping WBS element 6 corresponds to grouping of all orders from Europe, including domestic orders.

WBS Elements

The following WBS elements have been created in different projects: WBS 1.1, WBS 1.2, WBS 2.1, WBS 2.2

Assignments Between WBS Elements and Grouping WBS Elements

You must maintain the following assignments between WBS elements and grouping WBS elements:

Assigning the Materials to Grouping WBS Elements in MRP

The finished product is not allowed to be planned with requirements grouping. It is therefore planned with the WBS element.

The assembly underneath the finished product is planned with the grouping WBS element 1, 2 or 3, if its MRP group has been assigned to the grouping WBS elements and the WBS elements, which have caused the requirements, have been correctly assigned.

The materials in the BOM levels underneath this assembly, on the other hand, are planned with the grouping WBS elements that are correspondingly lower in the hierarchy, if the MRP groups are assigned to the grouping WBS elements and the WBS elements are assigned as displayed in the table. Important raw materials in the example above are planned with grouping WBS element 6. This also applies if the raw material is used for the final assembly and therefore a dependent requirement is at the highest BOM level.

Materials from the lowest BOM level (usually less important raw materials) are not planned using requirements grouping but rather as collective requirements.