What are the main processes of precision machining?

First, CNC precision machining sequence

When the mold is very large and deep, the preliminary processing before heat treatment, semi-deep processing with soft production processing, deep processing after heat treatment with hard production processing; Small, shallow molds can be milling in one go after heat treatment. If the mold wall is very thin and the mold core is very deep, metal work is used.

If the mold core has a large and flat bottom edge, with integrated milling cutter plate to carry out primary processing, and then use round nose milling cutter clear Angle, the effect of integrated milling cutter plate drilling amplitude and thinning heat is very good. Round nose milling cutter in the production must clear the root position than thick bottom cutter high efficiency, not easy to break the edge

Two, CNC precision machining tool selection

It is very important to choose milling cutter properly when CNC precision machining and hard die. In general, the selection of high stiffness tool body design, heat resistance, wear resistance coating, metallurgical material manufacturing tool is effective selection, Zhongshan Ailang high precision tool released fast and high toughness H series products completed fast and high toughness HRC70 production and processing. In addition to the tool stiffness is very important, in order to better improve the stiffness of small diameter milling cutter, the diameter of the handle is much larger than the tool diameter, in order to improve the production of smooth and clean processing and increase the service life of the tool; The overhang length of tool clamp should be as short as possible. On the other hand, select a new coating, so that the tool can withstand higher drilling temperatures, such as Tisin and Cygnus-X coating alkali temperature of 1300℃, surface strength Hv3700, coating thickness of 4um, therefore, they are more suitable for fast and hard heat treatment mold production processing

Three, CNC precision machining tool holder selection and tool clamping

The handle should have rotor dynamic balance or selected calcined handle, at the same time the shape of the handle should be integrated into the mold structure. Generally, a half degree gap should be maintained between the milling cutter and the side of the casting, such as the side of the product workpiece is a 3° slope, and the appearance design of the handle is made of 5/2, in order to obtain very large stiffness. If the side of the workpiece is 90° facing, the handle should be of thin neck construction.

Clamping milling cutter is very important, which involves the tolerance of the size of the shank, the mutual cooperation of the shank and the clip, and the diameter jump after installation. Therefore, the shank should be manufactured to a tolerance of -0.0025mm to -0.005mm, or to clamp the tool with a heat shrink clamp.

Four, CNC precision machining CNC lathe selection and CNC program writing key points

The application of good stiffness, high precision CNC lathe can get good practical results. The spiral tool radius compensation should be used in the way of cutting into the die when the program of production and processing of high toughness die, which is more stable in the whole process of cutting. In places where cutting from the side or spiral is not possible, oblique wave cutting should be used to prevent radial cutting. The program also determines the size of the axial feed and drilling depth.