Общий каталог FANAR 2021 - страница 290

Technical information i Straight Flutes with Spiral Point Designed for through holes, with thread along the full length of the hole. Used together with the chamfer B, it is recommended for materials giving a long chip. The spiral point moves tightly squashed chips in the direction of feed, and prevents the grooves from clogging. Coolant reaches the working zone freely. The length of threads, which can be made - up to ca 3xD. Spiral flutes Together with the chamfer C and E used for the blind holes. It is recommended for materials giving a long chip. Spiral flutes provide good chip evacuation in the direction from the hole toward the shank. Depending on the hole diameter, it is possible to make threads of up to 2,5xD. Machine tap with spiral flutes should not be used for the through holes. 4.6. Types of the high performance machine tap center holes, depending on the diameter of the thread, chamfer and the applied standards Working Part Shank Solid cone 1 Stepped cone 2 5 Phase Chamfer E 3 (without center hole) Internal center hole 4 6 Internal center hole External thread Type of center hole on cutting segment side Type of center hole diameter (mm) Chamfers A, C, D, Chamfer B Chamfer E, F on shank side ≤7,2 1 1 3 5 DIN-371 7,2≤8,2 2 1 3 5 8,2<10,2 2 2 3 5 DIN-374 ≤7,2 1 1 3 5 12 DIN-376 DIN-5156 >7,2 4 4 4 6 287