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With the development of auto manufacturing industry, through the introduction of a large number of high-end equipment gear industry makes the processing ability has made great progress with the international advanced level has been quite close to. Homemade gear processing machine tool has been basically formed a relatively complete series has developed technology that has international level of six axis NC grinding machine for spiral bevel gear, but the gear machine tool overall manufacturing level in precision, life, stability, numerical control technology and other aspects compared with the western countries there is a big gap between the present domestic gear processing industry processing especially for CNC gear machine tools are mainly to imports of equipment. Such as Germany pfauter company, Swiss reishauer company cylindrical gear hobbing, gear grinding machine, the United States of America Gleason company, Germany Colin Begg company （ including the original Swiss oer likon ） spiral bevel gear milling, grinding, lapping machine and gear measuring center in China remains a significant advantage.

Gear processing according to the different structure and precision needed by different process. In view of large equipment investment, technology selection （ Table 1） are usually considered to existing resources. Gear during the processing of small deformation and process stability control is relatively complex, rough forging mostly using isothermal normalizing, in order to obtain the good processing performance and trend deformation homogeneous microstructure: for high precision low speed cylindrical gear can heat before shaving heat longer after processing: cylindrical gear heat processing according to the conditions of Qi teeth and gear grinding different options, the cost is low but the clear tooth profile modification ability is weak, grinding high precision but high cost: the edge trimming and drum gear profile modification technology can significantly reduce the gear meshing noise and improve the transmission performance, widely used. Straight bevel gear is mainly used for differential due to low speed precision requirements are relatively low, the current recommended the use of precision forging spur gear. Spiral bevel gear processing calculation and adjustment of machine tool, the past is very complex and time-consuming manual operation has been modern specialized software and computer program are replaced, the finite element analysis of the introduction of design parameters is more reliable and convenient: spiral bevel gear heat processing mainly lapping and grinding teeth two, due to the cost of grinding tooth high, low efficiency and limitations of the currently used mostly lapping, lapping geometric correction ability is very weak, so the spiral bevel gear driven gear by carburizing press quenching process. Gear materials and heat treatment technology development is in gear machining on deformation control of a challenging topic.