6. Process implementation

6.1 Preparing drafts

The method of obtaining blanks is linked to the flow-forming process.

Tapered flow-forming uses cut or sheared blanks from rolled sheet metal. Pre-forming becomes necessary to obtain cones with a very narrow angle (α < 12°).

In cylindrical flow forming, the short-length starting cup is obtained :

• mass machining, for small production runs (10 to 100 parts);

• stamping or extrusion followed by machining, for medium and large production runs (from a few hundred to tens of thousands of parts).

The qualities required for these parts include surface finish, thickness consistency and microstructure....