Views: 77 Author: Site Editor Publish Time: 2022-06-14 Origin: Site
In the CNC milling process of mold and other workpiece cavities, when the cutting point is a concave part or deep cavity, the extension of the tungsten steel milling cutter needs to be lengthened. If a long flute tungsten steel milling cutter is used, the deflection of the cutter is large, which will cause vibration and breakage of the cutter.
Therefore, in the process of machining, if only the cutting edge near the end of the tool is required to participate in the cutting, it is better to use a short-edge long-shank tungsten steel milling cutter with a longer total tool length. When using large diameter tungsten steel milling cutters on horizontal CNC machine tools, the deformation caused by the self weight of the tool is larger, so much attention should be paid to the problems that can easily occur with end cutting. In the case of long-edge tungsten steel milling cutter must be used, it is necessary to significantly reduce the cutting speed and feed rate.
The selection of cutting speed mainly depends on the material of the workpiece being processed; the selection of feed rate mainly depends on the material of the workpiece being processed and the diameter of the tungsten steel milling cutter. Some foreign tool manufacturer's tool samples with cutting parameters selection table, available for reference. But the choice of cutting parameters at the same time by the machine tool, tool system, the shape of the machined workpiece and clamping method and other factors, should be adjusted according to the practice of appropriate cutting speed and feed rate.
When the tool life as a priority factor, can be appropriate to reduce the cutting speed and feed rate; when the chip is not good off the edge, it can be appropriate to increase the cutting speed.
The use of smooth milling is conducive to preventing damage to the cutting edge, which can improve tool life. But there are two points needing attention: ① such as the use of ordinary machine tool processing, should try to eliminate the gap of the feed mechanism; ② when the workpiece surface residual casting, forging process consisting of oxide film or other hardening layer, it is appropriate to use reverse milling.