Gear heat treatment quality continues to improve

With the development of my country's gear products in the past ten years, many products have reached or are close to more advanced levels. However, in order to improve the wear resistance and practicality of gears, there are still a considerable number of gear and gearbox products that are not as good as in terms of vibration, noise and fatigue life. The gap between the more advanced levels is obvious, and this is closely related to the level of gear materials, heat treatment equipment and technology. They have become the bottleneck for China's gear products to catch up with the international level.

Recently, the gear carburizing and quenching process has attracted many industry experts and representatives from gear manufacturers, heat treatment equipment and auxiliary material manufacturers to gather together to further improve the quality level of gears. The most outstanding performance of gear quenching is to improve the quality, depth and accuracy of quenching. The degree of numerical control of complete sets of heat treatment process equipment in my country has been significantly improved. "Zhengzhou Gou's" induction heating equipment does an excellent job in gear quenching. The quality of quenching is good, and all the requirements for gears have reached the technical level. Many commonly used gear manufacturers use induction heating equipment. Nowadays, gear carburizing, heat treatment processes and complete sets of equipment with Chinese characteristics compete with more commonly used foreign brands. The market share of domestic heat treatment equipment is increasing year by year, with Strong competitiveness, domestic box furnaces, continuous furnaces, and pit furnaces are all very famous, and domestic carburizing technology has attracted the attention of foreign technology companies.

Of course, there is still a gap between my country's gear products and foreign countries. For example, taking vehicle main reduction spiral bevel gears as an example, except for a few companies whose products have reached or are close to foreign advanced levels, most companies' products are on par with foreign countries in terms of fatigue life and noise indicators. There is a large gap in advanced levels, and companies are trapped in vicious competition at low prices. And its quality level has an important relationship with the material and heat treatment level. The improvement of automobile transmission product quality begins with the study of controlling gear heat treatment deformation. Gears are developing in the direction of heavy load, high speed, high precision and high efficiency, and strive to be small in size, light in weight, long in life and economical and reliable. The development direction of gear theory and manufacturing technology is:

1. Further study the mechanism of gear damage, which is the basis for establishing a reliable strength calculation method, the theoretical basis for improving the load-bearing capacity of gears and extending the life of gears.

2. Develop new tooth shapes represented by arc tooth profiles

3. Use cold forming processing, precision casting, powder metallurgy and other process methods for medium and small gears to increase productivity and reduce costs while ensuring accuracy.

4. Considering the elastic deformation of the gear, manufacturing and installation errors, and the distribution of the temperature field, modify the gear teeth to improve the smoothness of the gear operation and increase the contact area of the gear at full load, thereby improving the load-bearing capacity of the gear.

The gear industry is mainly composed of three types of enterprises: vehicle gear transmission manufacturing enterprises, industrial gear transmission manufacturing industry and gear special equipment manufacturing enterprises. Among them, vehicle gears stand out, with their market share reaching 60%. Industrial gears are composed of industrial general, special and special gears, with market shares of 18%, 12% and 8% respectively. Therefore, Zhengzhou Gou's induction heating equipment for making gears is very efficient, fast, safe and environmentally friendly, and is the first choice of many large enterprises.