Machining closed pockets
Closed pockets are usually produced by roughing in Z planes. When milling, a ramp is often selected as the machining entry. The tool selected depends on the depth of the walls and the mould incline to be generated on the component. MAPAL’s broad portfolio with modular systems also covers the machining of deep pockets with large diameters.
Tool overview for the following machining steps:
Roughing
Roughing operations are responsible for most of the chip removal capacity. Special milling strategies such as high-feed machining or trochoidal milling can reduce machining time and thus increase profitability. In addition to tools with indexable inserts and solid carbide milling cutters, high-performance milling cutters with special roughing geometry are used.
Material residual desbaste
Após o desbaste, os usuários usinam o material residual, especialmente em cantos e cavidades, para uma tolerância o mais constante possível em uma segunda etapa de usinagem. Normalmente, são utilizadas ferramentas com raio da aresta ou fresa de alto avanço. Se necessário, uma fresa esférica também pode remover o material residual nos cantos.
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.
Finition
L'usinage de finition enlève la surépaisseur restante pour obtenir la forme finale. Après la semi-finition, la valeur est de 0,05-0,1 mm pour les matériaux trempés et de 0,1-0,3 mm pour les matériaux tendres. Les fraises sphériques et/ou fraise rayonnée sont le moyen de choix, en fonction des contours finaux de la pièce.
Finition de la matière résiduelle
Les propriétés de plus en plus complexes des moules à produire nécessitent, après l'usinage de finition, un fraisage de la matière résiduelle, principalement dans les angles. Les fraises sphériques en carbure monobloc sont généralement utilisées à cet effet.