The mechanical design conceptualizes, analyzes and calculates the working principle, structure, motion mode, force and energy transfer mode, material and shape size of each part, lubrication method, etc. according to the requirements of use and translates it into a specific description. The work process on which the manufacturing is based. Mechanical design is an important part of mechanical engineering, the first step in mechanical production, and the most important factor in determining mechanical properties. The goal of mechanical design is to design the best machinery under a variety of defined conditions (such as materials, processing capabilities, theoretical knowledge and calculation methods), that is, to optimize the design. Optimizing the design requires a comprehensive consideration of many requirements, generally: best performance, minimum manufacturing cost, minimum size and weight, most reliable use, minimum consumption, and minimal environmental pollution. These requirements are often contradictory, and the relative importance between them varies by machine type and use. The designer's task is to weigh the weight according to the specific situation and make overall considerations, so that the designed machine has the best comprehensive technical and economic effects. In the past, design optimization relied primarily on the knowledge, experience, and vision of the designer. With the development of new disciplines such as mechanical engineering basic theory and value engineering, system analysis, the accumulation of technical economic data produced and used.