Production Backflush for Interchangeable Products
Use
The
Production Backflush in SAP APO
respects the sequence you defined in the
supersession chain
of an interchangeability group.
Prerequisites
You have executed an ATP Check for the planned orders you want to backflush.
Features
Business Add-In /SAPAPO/PPC_BADI
The BAdI /SAPAPO/PPC_BADI is available in the production backflush to check whether an ATP check has been carried out for planned orders with interchangeable products. Before you can execute the production backflush, you must have executed an ATP check for the planned orders as the interchangeability data can only be transferred to the planned orders via this check. In this process, the requirement quantity of a component to be discontinued is split between the component to be discontinued and its successor. If this interchangeability data does not exist in the order, postprocessing records are created in the backflush. To avoid these postprocessing records, two alternative methods with example coding are available:
Method AFTER_CHECKS
Example coding is provided with this method for checking planned orders with interchangeable components. This check determines whether or not an ATP check has been executed for the planned orders. If no ATP check has been executed for a planned order, the system issues an appropriate error message.
Method AT_SAVE
Example coding is provided with this method for checking planned orders with interchangeable components. This check determines whether or not an ATP check has been executed for the planned orders. If no ATP check has been executed for a planned order, the system accesses the ATP check for the planned orders in question in the BAdI.
Backflush
The production backflush is created in SAP APO. The goods issue for the components is posted in the DI System . Here, the goods issue of the components to be discontinued as calculated by the matrix has to be posted as well as the goods issue of the successor product(s). The stocks in the DI System are reduced correspondingly.
If you execute a final backflush for an order without having carried out a partial backflush first, the goods issues are posted according to the requirements quantities of the components.
If you create several partial backflushes for an order, APO respects the sequence you defined in the product interchangeability group each time you backflush.
Reversing
When reversing , the original situation that existed before the backflush is reestablished – that is the quantities that existed before the backflush are reestablished (only for finally backflushed planned orders). The system can no longer reestablish the original quantities when reversing the backflush for planned orders that have not been completely confirmed (planned order was only partially backflushed or could not be confirmed).
Postprocessing Records
If postprocessing records are still created in the backflush, you have to process them manually in the DI System. See also: Postprocessing Goods Movements
Partial Backflushes: Example
Order 4711 for the finished product Y for 40 pieces triggers a dependent requirement for component A for 40 pieces.
Component A is to be substituted by B and later B is then to be substituted by component C (A
B
C).
For this purpose, you have created an interchangeability group of the type supersession chain in APO.
Using the ATP check, substitution is executed in order 4711 and the corresponding components are created. The following situation now exists in the order:
Component A: 10 pieces
Component B: 15 pieces
Component C: 15 pieces
As a result of a partial backflush for 7 pieces and the resulting goods issue posting, the requirement for component A is reduced by 7 pieces in the planned order. Now, the following situation arises:
Component A: 3 pieces
Component B: 15 pieces
Component C: 15 pieces
Another partial backflush for Y for 10 pieces is carried out. Due to the goods issue posting, a requirement quantity of 10 pieces must be reduced in order 4711. Then, the system reads the sequence of the substitution in the interchangeability group. The system first reduces the requirement quantity of A to 0 and then reduces the requirement quantity of B by 7 pieces. Now, the following situation arises:
Component A: 0 pieces
Component B: 8 pieces
Component C: 15 pieces
In the next partial backflush for 10 pieces, the goods issue is posted for B and C and the requirement in the order is reduced. (8 pieces of B and 2 pieces of C)
The goods issue is posted for C (13 pieces) at the final backflush and the requirement in the order is reduced to 0 accordingly.