The design of mechanical parts, not only to meet the requirements of the use, that is, with the required ability to work, but also to meet the production requirements, otherwise it may not be produced, or although it can be manufactured but the cost is not economical. In the specific production conditions, such as the design of mechanical parts easy processing and processing costs are very low, then such parts are called a good process. The basic requirements of the process are: (1) The method of the blank preparation in the reasonable mechanical manufacturing is: direct use of profiles, casting, forging, stamping and welding. The selection of blanks is related to the specific production technical conditions, which depends on the production volume, material properties and processing possibilities. (2) When the structure of the parts is simple and reasonable design, the police use the simplest surface (such as plane, cylindrical surface, spiral surface) and its combination, but also should try to minimize the number of machined surface and the smallest processing area. (3) To specify the appropriate manufacturing accuracy and surface roughness parts of the processing costs with the increase in precision, especially in the case of high precision, this increase is very significant. Therefore, in the absence of sufficient basis, should not pursue high precision. Similarly, the surface roughness of the parts should be made appropriate according to the actual needs of the surface.