Scrap Calculation (PPM, R/3 RTO)
Use
If you plan in SAP APO on the basis of production process models (PPMs) or R/3 runtime objects (R/3 RTO), the system is able to take account of assembly scrap and activity scrap in procurement planning for a product produced in-house.
Assembly scrap
With the assembly scrap in the location product master, you describe what percentage of scrap arises when a product is produced. The percentage refers to the total procurement quantity, in other words to the sum of the yield and the quantity of the defective parts. The system takes the assembly scrap into account automatically in the procurement quantity calculation. The system determines the procurement quantity automatically from the desired yield and the assembly scrap. The assembly scrap is valid, irrespective of the source of supply and is thus independent of the manufacturing method used. For more information, see Calculation of Assembly Scrap (PPM, R/3 RTO) .
Activity scrap
With the activity scrap, you describe in detail in the plan for the source of supply what percentage of scrap is produced in each activity. The scrap refers to the total quantity of the order product to be processed by the activity. The system takes the activity scrap into account when the plan is exploded. The system automatically determines the total quantity from the yield produced by the activity and the activity scrap. The desired yield could be the procurement quantity of the order or the yield required by the successor activity. The latter applies if the scrap from consecutive activities cumulates. With the activity scrap, you can model scrap depending on the manufacturing process used. For more information, see Calculation of Activity Scrap (PPM) .
Since the system considers both types of scrap during planning, you should make sure when modeling the data that you do not plan too much scrap.
Example
You create an order manually and enter a yield of 100 pieces. In the location product master, you have entered assembly scrap of 20%. The system therefore creates an order with a yield of 100 pieces and a procurement quantity of 125 pieces. In the PPM plan, you have specified activity scrap of 50% for the first activity of the order. To allow the procurement quantity of the order of 125 pieces to be achieved, the activity must process 250 pieces, meaning that the system calculates the component quantity required by this activity, the activity duration, and the resource consumption for a total quantity of 250 pieces.
Note
In SAP R/3, unlike in SAP APO, you enter the assembly scrap as a percentage of the required yield. When scrap data is transferred from SAP R/3 to SAP APO, the system automatically converts the SAP R/3 scrap into SAP APO scrap. Therefore, the scrap values in SAP APO differ from the scrap values in SAP R/3. Apart from small rounding-related variances, however, the scrap data is the same. For more information on the differences in the scrap calculation and on integrating scrap data, see SAP note 390850.