Supersession Chain
Definition
A supersession chain is a sequential relationship of products that can replace each other.
For example, product A is substituted for product B due to changes in design, form, function, or manufacturing process.
Use
Changes to the design, form, and function of products require vendors and manufacturers to replace obsolete products with new versions of the same products. This is particularly important for the aftermarket environment where technical innovations produce a constant flow of new products (of a better quality or in a different form) that supersede older products.
This constant process of exchange is mapped using the SAP APO system.
You can create the following product substitution scenarios by means of a supersession chain:
Product Substitution Scenario |
Description |
One-to-one substitution (1:1) |
A product is replaced by another product. This process is also called discontinuation. A product is replaced by an assembly. |
One-to-many substitution (1:n) |
A product is replaced by a group of individual products: A → (B, C). This group of products is also called product combination. An individual product is replaced by different products based on certain conditions, such as vehicle model. |
Many-to-one substitution (n:1) |
A group of products is replaced by a single assembly. A number of different products are replaced by the same product: (A, B) → C. |
Many-to-many substitution (n:m) |
A group of individual products is replaced by another group of individual products. |
One-to-zero substitution (1:0) |
A product is not replaced by another product. This process is also called product obsolescence. |
Multi-level replacement |
A substituted product is again substituted with a new product or a group of products. This could be a combination of one-to-one, one-to-many substitutions, or a combination of both types of substitutions. The multi-level replacement is controlled by an indicator in the application that uses the interchangeability service and not in the interchangeability master data user interface. |
The nature of a product substitution scenario depends on its replacement type.
Structure
The header of every supersession chain contains an additional tab for location data.
The item data of every supersession chain comprise discontinuation steps with predecessor product/assembly, successor product/assembly, and master data attributes.
In Customizing for Product and Location Interchangeability you can maintain the attribute settings by choosing Application Settings → Maintain Attribute Properties for Supersession Chains. Depending on the application that uses the interchangeability group, you can specify whether an attribute is required, display only, or inactive.
In addition, you can control whether an attribute needs to be maintained at location level, cross-location level, or at both levels.
The following table lists all master data attributes available for a supersession chain.
Attribute |
Description |
Predecessor valid-from date |
The date from which the first product of a supersession chain will be valid. |
Valid-from date |
The date from which the successor product is valid for the supersession chain. The new product replaces an old product from this point in time onwards. When a new product becomes valid, this does not automatically mean that the old product is no longer valid. |
Use-up strategy |
An indicator that shows how the stock of the old product is to be used. |
Use-up date |
The date until which the old product can be used. |
Reason |
Indicates why the product is to be replaced. In Customizing for Product Interchangeability you define the reason codes by choosing Maintain Reason Code. |
Rule profile |
States the conditions under which the relationship of the interchangeability group is valid. There is no logic to evaluate the rule – only a placeholder where the rule can be entered. A BAdI is provided to evaluate the rule and to determine what should happen when the rule is valid or invalid. |
Direction of interchangeability |
Describes the nature of the product replacement. Products can be fully interchangeable or forward only: Forward The product replacement is performed in one direction only: A → B. This means, B can replace A if A has been ordered. However, A cannot replace B if B has been ordered. Full The product replacement is performed in both directions, forward and backward: A « B. This means that B can replace A if A has been ordered. A can also replace B if B has been ordered. |
Preceding quantity factor |
Numeric values that represent the relationship between the number of predecessor products and the number of successor products. |
Succeeding quantity factor |
|
Priority factor |
A numeric value that specifies the priority of each branch of a supersession chain. |
Demand percentage for demand quantity |
A numeric value that specifies the proportion of the demand history for the predecessor product that is transferred to the successor product. |
Successor product planning date |
The date on which the system realigns demand history and starts ordering the successor product from the supplier. The successor product planning date is calculated by the system. |
Stock exhaustion date |
A location-dependent date on which the stock is expected to be used up. The stock exhaustion date is calculated daily by the system. |
Stock exhaustion warning date |
The date on which there is an unexpected increase in demand for the predecessor product. The stock exhaustion warning date is calculated as soon as the successor product planning date is reached. If the daily calculated stock exhaustion date is the same as or earlier than the stock exhaustion warning date, an alert is sent to the planner. |
Successor product receipt date |
Date on which the successor product arrives at the entry location of the bill of distribution (BOD). The successor product receipt date is calculated by the system and is the successor product planning date plus the supplier delivery time to the entry location. |
Data realignment end date |
The date in a partial substitution from which the successor product receives its own orders. |
Additional information |
User definable text to save further information, for example, the predecessor usage strategy. |
For more information about header and item data, see Interchangeability Group Types.
Integration
The supersession chain is supported by the following applications:
· Demand Planning (DP)
· Supply Network Planning (SNP)
· Capable-to-Match (CTM)
· Service Parts Planning
· Production Planning and Detailed Scheduling (PP/DS)
· Global Available-to-Promise (Global ATP)
Not all applications support all the product substitution scenarios that you can create in the interchangeability master data. You can find detailed information on which application supports which substitution scenario in the documentation of the corresponding application.
Example
Supersession chain: A → B « C « D → E
In the above supersession chain:
· Product A and product B have forward interchangeability
· Product B and product C have full interchangeability
· Product C and product D have full interchangeability
· Product D and product E have forward interchangeability