The main processes of precision machining include three types, namely soft machining, hard machining and electric machining. So how do we choose the process? Here we come to give you specific introduction
One, cnc precision machining order
When the mold is large and deep, soft machining is used for rough machining and semi-finishing before quenching, and hard machining is used for finishing after quenching; small, shallow molds can be milled once after quenching. If the die wall is thin and the cavity is very deep, electrical machining is used.
If the mold cavity has a large and flat bottom surface, then after the rough machining with the integrated milling cutter disk, and then using the round nose cutter to clear the corners, the cutting force of the integrated milling cutter plate and the effect of dispersing heat are very good. Round nose cutters are more efficient than flat-bottom knives in processing parts that need clear roots, and are not easily broken
Second, the choice of nc precision machining tools
When cnc precision machining hard die, it is very important to choose the correct cutter. In general, the choice of high-rigid blade design, high temperature resistant, wear-resistant coating, cutting tools made of superhard material is preferred, high speed and high hardness H series introduced by Zhongshan Ilon Precision Tooling achieve high speed and high hardness below HRC70 . In addition, the rigidity of the tool is very important. In order to increase the rigidity of the small-diameter cutter, the diameter of the tool holder is made much larger than the tool diameter to improve the machining finish and prolong the tool life; the tool holder clip length should be as short as possible. On the other hand, new coatings were selected to enable the cutters to withstand higher cutting temperatures. For example, Tisin and Cygnus-X coatings were subjected to an acidification temperature of 1300°C, a surface hardness of Hv3700, and a coating thickness of 4 μm. Therefore, they are more suitable for high speeds. Hardened and hardened mold processing
Three, cnc precision machining tool holder selection and tool clamping
The holder should be balanced or the sintered holder should be selected, and the shape of the holder should be adapted to the structure of the mold. It is usually necessary to maintain a half-degree clearance between the side of the cutter and the workpiece. For example, if the side of the workpiece is a 3° bevel, then the shape of the handle is 5/2 for maximum rigidity. If the side of the workpiece is 90° straight, the holder should have a narrow neck structure.
It is very important to install the milling cutter, which involves the tolerance of the holder, the fit of the holder and the holder, the radial jump after installation and other factors. For this purpose, the manufacturing tolerance of the tool holder should be -0.0025mm to -0.005mm, or use a hot shrink clamp to clamp the tool.
Four, nc precision machining machine tool selection and NC programming points
Use rigid, high-precision machine tools to get good results. During the programming of high-hardness molds, the path of the tool cutting into the mold should be spiral interpolation, and the cutting process is more stable. Where it is not possible to use incisions from the side or spiral, a ramp cut should be used to avoid axial cuts. Programming also determines the size and cutting depth of radial passes