Solution : https://service.sap.com/sap/support/notes/538512 (SAP Service marketplace login required)
Key words : 
special procurement key 'direct procurement', create production orders, configured sales orders, read master data, direct procurement, master data, -inventory-managed, -stock component, inserted manually, terms co01
Related Notes : 
       
| 555387 | Externally procured components not relevant to costing | 
| 516986 | Purchase requisition generated for components | 
| 506239 | Direct procurement for reservations to KMATs | 
| 492993 | Adding components, incorrect configuration determined |