Solution : https://service.sap.com/sap/support/notes/188705 (SAP Service marketplace login required)
Key words : 
additional key words co01, header quantity, production order, component quantities, component scrap, material master, implemented note 112062, implement notes 126201, solution implement, attached corrections
Related Notes : 
       
| 377648 | Incorrect requiremt quantity after header change in quantity | 
| 363865 | Assembly scrap for dummies | 
| 147672 | Header quanty change: Scrap not taken into account | 
| 126201 | CO01:Error ME101 after implmentation of Note 112062 | 
| 112062 | CO01/02:Incor. phantm qties when changing headr qty |