The CNC Machining, CNC turning, Auto lathe turning, CNC Milling,Stamping, Sheet metal fabrication, Casting, Injection molding are the common machining process.
1. Rough turning is the most economical and effective method for rough machining of outer circle. Since the main purpose of rough turning is to remove excess metal from the blank quickly, increasing productivity is its main task. Rough turning usually use the maximum back feed and knife feed to improve productivity. In order to ensure the necessary tool life, cutting speed is usually lower. In order to reduce the back force and prevent the bending deformation and vibration of the workpiece, the turning tool should select the larger main deflection angle, the smaller front angle, the rear angle and the negative edge inclination angle, so as to enhance the strength of the cutting part of the turning tool. The machining accuracy of rough turning is IT12 / ITll. the surface roughness Ra is 50 ~ (12) μ m ~ (12.5) μ m.
2. The main task of the finishing is to ensure the machining accuracy and surface quality of the parts. The outer surface of the finishing is generally machined with small feed and high cutting speed. When machining the outer circle of large shaft parts, a wide-blade turning tool is often used for low speed finishing. In order to improve the quality of machined surface, larger front angle, rear angle and positive dip angle should be used for turning tool. The finishing machine can be used as the final process of high precision outer circle or as the preprocessing of fine machining. The machining precision of the finishing is up to IT8~IT6 grade, and the surface roughness Ra can reach 1.6 μ m and 0.8 μ m.
3. The features of the fine turning are as follows: the feed and the back feed are very small, and the cutting speed is as high as 150 ~ 2000m / min. The cutting tools of superhard materials such as cubic boron ammoniated (CBN), diamond and so on are generally used in fine turning. The machine tools used must also be high precision or precision machine tools with high speed rotation and high stiffness. The machining accuracy and surface roughness of the fine turning are about the same as those of the conventional cylindrical grinding. The machining accuracy can reach above IT6, and the surface roughness Ra can reach 0.4 μ m and 0.005 μ m respectively. Most of them are used for precision machining of non-ferrous metal workpiece which is not easy to be machined. It is more effective for aluminum and aluminum alloy workpiece which is easy to plug the hole of grinding wheel. In the machining of large precision outer surface, fine turning replace grinding machining.