The Warehouse Structure in WM 


Before you can use the SAP Warehouse Management (WM) application, you must first define the structure (physical layout) of your warehouse or warehousing complex.

The Warehouse Structure Without WM

When Warehouse Management is not in use, the lowest level of stock management is the storage location. In the Inventory Management (IM) application component, the storage location is defined as the location of physical deposits of stock within a plant. In this case, storage locations make up the various storage facilities (or areas) of a warehousing complex (for example, high rack storage, picking area or bulk storage). However, you can only manage the stock of a material in one storage bin. This bin is different from a WM storage bin in that it is entered into the material master record at the storage location level.

If you use IM without WM, you can assign one or more physical storage locations to each plant as shown in the figure below:

In this figure, storage locations have been defined for two plants. The first plant has two storage locations: for example, 0001 for high rack storage and 0002 for bulk storage. Three storage locations have been assigned to the second plant: 0001 for high rack storage, 0002 for bulk storage and 0003 as a picking area.

When you use IM without WM, the system provides information about stock quantities at the storage location level as summarized values. It cannot provide information about individual pick slots, such as which materials are stored in specific storage bins.


The Warehouse Structure With WM

When you implement the Warehouse Management (WM) application in a plant, you assign the warehouse number to one or more MM storage locations and the individual storage areas (for example, high rack storage and so on) are assigned as separate storage types under the warehouse number (complex). Although possible, the definition of several storage locations for one plant is only necessary for special situations. One situation would be when there are additional warehouses (storage areas) within a plant that are not managed using WM.

When you install WM, although data about the stock quantities is managed at the storage location level in IM, you manage information about the actual storage bin location of the material in the warehouse in WM.

To link the information at the storage location level to information from the storage bin, you assign the IM storage location to a warehouse number in WM as illustrated below:

This figure depicts two plants that each manage a storage location using WM. Storage location 0088 in the first plant is assigned to warehouse number 001. Two storage types are assigned to warehouse 001. Storage location 0088 in the second plant is assigned to warehouse number 002. In warehouse complex 002 there are three storage types. In WM you define storage bins for each of the storage types. WM then manages data about all of the materials stored in each of the storage bins in the entire warehouse.

You can also manage stock for several plants in the same warehouse at the same time. In this case, you would assign the storage locations for these plants to the same warehouse number as shown below.

Although it is generally advantageous to assign one plant/storage location combination to one warehouse number, you can also assign more than one storage location per plant to a single warehouse number.

For scenarios associated with this structural configuration, see Storage Locations in TRs, TOs and Posting Changes.

Setting up the Connection Between IM and WM

You set up the link between a plant storage location in IM and a warehouse number in WM under Enterprise Structure ® Assignment ® Materials Management in the Enterprise Management IMG.

The system uses the links that you create to the Inventory Management (IM) application component to ensure that certain processes in the Quality Management (QM) component, the Product Planning (PP) component, and the Sales and Distribution (SD) component are carried out in WM for the appropriate warehouse number.


What does the warehouse structure look like in WM?

The warehouse structure in Warehouse Management is hierarchical and consists of the following elements:

You can define an entire physical warehousing complex in WM using a single warehouse number.

Each of the storage facilities or areas that make up the warehousing complex can be defined as a type of storage area or "storage type" by its spatial, technical and organizational factors.

Each storage type is divided into storage sections. A storage section generally includes all bins that have certain characteristics in common, such as bins for "fast-moving items" near a goods issue area. You can set your own criteria for grouping bins into a storage section.

Each storage type and section consists of several storage spaces or slots. These are called storage bins in WM and are the smallest addressable unit of space in a storage type. Storage bins are identified by coordinates that refer to the exact position where goods can be stored in the warehouse.

The quant is used to separate goods in the storage bin based on their differing characteristics.

You can create this structure in WM using the Warehouse Management IMG to assimilate the layout of any physical warehouse.

Creating the Warehouse Structure in WM

You should define the warehouse structure in the following order:

  1. Define the warehouse number (Customizing).
  2. Define the storage types (Customizing).
  3. Define the storage sections (Customizing).
  4. Create the storage bins (WM function).