Automobile gears are generally specialized in mass production. Cylindrical gears and bevel gears are widely representative, and different process combinations are used according to different structures and precision requirements. Due to the large investment in equipment, the selection of process methods usually fully consider existing resources.

The small deformation and process stability control during gear machining is relatively complicated. After forging, most of the blanks need to be normalized by isothermal, in order to obtain good processing performance and uniform metallographic structure with trend deformation; for low-speed mesh gears with low precision requirements, the gears can be shaving before hot and no longer processed after hot, radial shaving The application of gear method expands the application range of gear shaving; cylindrical gear thermal post-processing has two methods: honing and grinding. The cost of honing is low, but the ability of tooth shape correction is weak, and the grinding precision is high and the cost is high. It adopts the direction along the tooth height. The advanced tooth tip trimming and the drum-shaped tooth trimming process along the tooth length direction can significantly reduce gear meshing noise and improve transmission performance, which is a research field that has received widespread attention.

Straight bevel gears are mainly used in differentials. Due to low speed and relatively low precision requirements, precision forging tooth profile is an important development direction. In the calculation of spiral bevel gear processing and machine tool adjustment, the previous very complicated and time-consuming manual operations have been replaced by modern special software and computer programs. The introduction of finite element analysis makes the design of process parameters more reliable and convenient. Spiral bevel gears have two types of thermal post-processing: grinding and grinding. Because of the high cost, low efficiency and limitations of grinding, the grinding is currently mostly used. The geometrical correction ability of the grinding is very weak. Driven gears are mostly carburized and press-quenched. The development of gear materials and heat treatment technology is a challenging subject for deformation control in gear processing.