With the development of industry, various special engineering materials with high strength, high hardness, high temperature resistance and corrosion resistance are more and more used in metalworking industry. This puts forward higher performance indicators for the performance, spindle and structure of NC machine tools with ultra-high speed cutting and ultra-precision technology, which should be fully considered in the selection of machine tools and control systems.
1. Point control cutting technology
For point-controlled CNC machine tools, only the positioning accuracy is high and the positioning process is as fast as possible, but the movement path of the tool relative to the workpiece is not important, so this kind of machine tool should arrange the tool path according to the shortest free distance. In addition, it is necessary to determine the axial motion size of the tool, which is mainly determined by the hole depth of the machined part, but some auxiliary dimensions, such as the introduction distance of the tool and the excess amount of the tool, should also be taken into account.
2. Cutting Technology for Thread Manufacturing
When turning threads on CNC machine tools, the feed along the pitch direction should maintain a strict speed ratio relationship with the spindle rotation, so cutting should be avoided in the process of accelerating or decelerating the feed mechanism. The numerical value is related to the dynamic characteristics of the machine tool, the pitch of the thread and the accuracy of the thread.
3. Planar milling cutting technology
When milling plane parts, the side edge of end milling cutter is usually used for cutting. In order to reduce the traces of the cutter and ensure the surface quality of the parts, the cutting and cutting procedures of the cutter need to be carefully designed. When milling the outline of outer surface, the cut-in and cut-out points of the milling cutter should cut into and cut out the surface of the part tangentially along the extension line of the outline curve of the part, instead of directly cutting into the part along the normal direction, so as to avoid scratches on the machined surface and ensure the smooth outline of the part.
IV. Cutting Technology for Inner Cavity Milling
When milling the inner contour surface, cut-in and cut-out cannot be extended. At this time, the cutter can cut-in and cut-out along the normal direction of the part contour, and the cut-in and cut-out points are selected at the intersection of the two geometric elements of the part contour. When the workpiece, tool, fixture and machine tool system are in equilibrium elastic deformation state, the cutting force decreases when the feed stops, which will change the balance state of the system. The tool will leave scratches on the surface of the part at the feed stop, so it will be in the outline.
Feed pause should be avoided.
V. Cutting Technology of Surface Cutting
Surface cutting often uses “line-cutting” method with ball-nose cutter. The so-called line-cutting method refers to the path of the cutting point between the cutter and the contour of the part is line-by-line, and the distance between the lines is determined according to the requirement of the processing accuracy of the part.
These are the precautions for different types of high-speed cutting technology. With the improvement of technology, numerical control technology plays an increasingly important role in manufacturing industry.
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