Dalian precision machining changed from manual machining to computer program to control the machine tool for machining. The repetitive machining precision of CNC machining is high, especially for some complex shapes that are difficult to be machined manually, such as machining a curved surface. It does not cause the chemical or phase change of the workpiece, which is called cold working. Generally, processing above or below normal temperature will cause chemical or phase changes of the workpiece, which is called hot processing.

Cold working can be divided into cutting and pressure machining according to the difference of machining methods. Hot working commonly includes heat treatment, forging, casting and welding. For some occasions, the higher the hardness of the material, the better. It is only limited to the hardness requirements of the processing machine parts. The processed materials cannot be too hard. If they are harder than the machine parts, they cannot be processed.

If the density is too large, the hardness is also very large, and if the hardness exceeds the hardness of the machine part (lathe tool), it cannot be machined. In the problem, the surface finish is 0.8. If it is Ra value, it can be regarded as precision machining. If it is RZ value, it is ultra precision machining. It is often more economical and easy to be vigilant against gross damage. Such as when finishing the tooth profile.

In order to ensure the coaxiality between the processed ring gear and the inner hole of the gear, the fit clearance between the gear and the spindle should be reduced. In production, it is often grouped according to the internal size of the gear, and then matched with the corresponding grouping mandrel, which evenly divides the original error caused by the clearance and improves the position accuracy of the gear ring.