Usinage de poches fermées
La fabrication de poches fermées s'effectue généralement par ébauche dans les plans Z. Dans ce cas, l'entrée d'usinage par une rampe est souvent choisie pour le fraisage. Le choix de l'outil dépend de la profondeur des parois et de l'inclinaison à créer sur le composant. Le large portefeuille de systèmes modulaires MAPAL couvre également l'usinage de poches profondes de grands diamètres.
Tool overview for the following machining steps:
Ébauche
L'opération d'ébauche est responsable de la majeure partie du volume d’usinage. Des stratégies de fraisage spéciales, telles que l'usinage grande avance ou le fraisage trochoïdal, peuvent réduire la durée d'usinage et donc augmenter la rentabilité. Outre les outils à plaquettes amovibles et les fraises en carbure monobloc, des fraises hautes performances à géométrie d'ébauche spéciale sont utilisées.
Residual material roughing
After roughing, in a second machining step, users machine the residual material, especially in corners and cavities, removing material as constantly as possible. Usually tools with corner radius or high-feed milling cutters are used. In some cases a ball cutter can be used to remove the residual material in corners.
Pre-finishing
If there are high demands on dimensional accuracy and surface finish, semi-finishing is recommended before finishing. With pre-finishing, machining approaches the final mould profile. The aim is to obtain a residual material that is as constant as possible in order to enable fast finishing with high demands on the surface quality. The stock removal after roughing is approx. 0.5-1 mm for hardened materials and 0.03-0.5 mm for soft materials. After pre-finishing, the constant stock removal is 0.05-0.1 mm for hardened materials or 0.1-0.3 mm for soft materials.
Finishing
The finishing process removes the remaining material in order to achieve the final shape. After pre-finishing, stock removal is 0.05-0.1 mm for hardened materials or 0.1-0.3 mm for soft materials. Ball and/or corner radius milling cutters are the tools of choice, regardless of the final contours of the workpiece.
Residual material finishing
The increasingly complex properties of the shapes to be produced require milling of the residual material after finishing, mainly in the corners. Solid carbide ball cutters are usually used for this.
