Improvement of heat treatment technology in Chinese gear production technology

With the deepening of the process of industrial globalization, environmental protection is another prominent and arduous task in front of the manufacturing industry. In addition to the requirements of reliability, the impact of noise generated by gear transmission on the environment, and the maximization of the utilization rate of energy and materials in gear production have become another new topic for gear manufacturers.

The traditional method of machining the inner hole of gear blank is to pull it out by broaching machine. Because the working condition of broach is to carry out many times of blade grinding, about one or two thousand pieces of gear blank should be broached once. In addition, the broach will produce wear during broaching, resulting in the size of the inner hole is not uniform. For this reason, Lin Mao proposed that in the process of gear cold machining, the same datum (inner bore datum) should be used to finish machining and hobbing shaving of gear blank. The uniform size of inner bore of gear blank has made important preparation for ensuring the quality of gear product.

The application of electronic computer makes all kinds of numerical control machine tools develop rapidly. Through the use of CNC lathe, the gear processing procedure is reduced, the production efficiency is improved, the production cost is reduced, and the processing quality of products is guaranteed. In his doctoral dissertation, Yang Yong established a new theoretical calculation model of hobbing deformation, dynamic vibration displacement and thermal deformation of large gear hobbing machine by theoretical, experimental and finite element research methods. The thermal error compensation model of the variation of the spindle center distance of the gear hobbing machine is established by combining the gear processing technology with the experimental test, the numerical control processing and the computer software technology.

At present, there are some problems in the plastic forming technology of spiral bevel gear at home and abroad, such as the low efficiency of ring rolling, blank preparation, high equipment input and low material utilization; the complex die structure, the press energy can not be fully used in the tooth forming, and the die is prone to stress concentration. Liang Hao et al. Developed a hot precision forging process plan of forming driven spiral bevel gear by “upsetting, pre forging, punching and final forging”. According to the process plan, a closed precision forging die with center split was designed, and the feasibility of the process plan and the correctness of finite element simulation were verified by simulation and experiment, which provided reference for the mass production of precision forging of spiral bevel gear. Improvement of machining technology.