Gear machining process is composed of several processes. In order to obtain gears that meet the accuracy requirements, the whole processing process is around the tooth profile processing process.

　　1. Raw material of blank

　　Blank is the basis of production and the starting point of the whole process design. In order to obtain high performance products and reduce heat treatment deformation, we should control the metallographic structure and other indicators of the blank. At present, the forging blank is generally used, and the preheating treatment methods such as normalizing or isothermal normalizing are carried out after forging. During our investigation in Europe, we noticed that gear manufacturers in Europe, including well-known manufacturers, rarely use forging blanks. From gear shafts, spline shafts to disk gears, and even spiral bevel gears with a diameter of more than 300 mm, most of them use round steel for blanking. Some even use a few meters long round steel to complete the gear blank processing on the lathe before cutting without blanking. Raw blanks can reduce cost and shorten production cycle. If the blank is not forged, the cost that can be saved includes forging fee, preheating fee, material heating and oxidation loss fee, transportation fee, etc. Directly using raw materials instead of forging blanks can generally save more than 20% of the blank cost and shorten the production cycle by about 10 days. For high-precision gears, high-quality raw materials and complete hot post-processing means are the prerequisites for raw materials of blanks.

　　2. Thermal Postprocessing of Tooth Surface Finishing

　　The process methods used for gear surface finishing mainly include gear shaving, gear grinding, gear honing and gear scraping. Except for gear shaving, the other three processes are all processed after heating. However, shaving is the most widely used and the most important gear surface finishing method due to its convenient adjustment, high processing efficiency, low investment and low cost. However, gear shaving cannot be hard processed. In order to eliminate the influence of heat treatment deformation, gear shaving is generally half to one level higher than the product precision. At present, although shaving is still a very important method of tooth profile finishing, it is increasingly replaced by gear grinding and shaving. Worm wheel grinding and form grinding are mainly used for gear grinding. Scraping is to hobb the gear again after heating. The gear precision processed after heating is the final precision of the part, so there is no need to worry about heat treatment deformation. This can reduce the technical requirements for improving the composition and metallographic structure of raw materials (blanks) to prevent heat treatment deformation, and reduce the blank cost and processing cost.

　　3. Remanufacturing technology

　　In the process of design and development of gear processing machine tools, full consideration should be given to the recycling of machine tool resources from the perspective of the whole life cycle, and methods such as disassembly and recycling design and modular design should be adopted to facilitate remanufacturing and technology upgrading after the machine tool is scrapped. The gear processing machine tool has a high recycling value, the recycling rate of reusable parts is high, and the remanufacturing cost is low. For example, the cost of remanufacturing gear hobbing machine is only 50~60% of that of new gear hobbing machine with the same technical level. Through remanufacturing, a large number of machine tool parts can be reused to avoid environmental pollution and resource and energy consumption in the process of manufacturing these parts (casting, welding, cutting and heat treatment, etc.), as well as resource consumption and environmental pollution in the process of recycling these parts.