Gear application

Plastic gear

With the development of science, gears have gradually changed from metal gears to plastic gears. Because plastic gear has more lubricity and wear resistance. It can reduce noise, cost and friction.

Common plastic gear materials are: PVC, POM, PTFE, PA, nylon, peek, etc.

Automobile gear

There are many steel grades for gears of medium and heavy duty trucks in China, mainly to meet the requirements of introducing foreign advanced automobile technology at that time. In the 1950s, China imported the production technology of Soviet medium-sized trucks (i.e. the original model of "Jiefang" brand) from the former Soviet rikhachov automobile factory, as well as the 20CrMnTi steel for automobile gears produced by the former Soviet Union.

After the reform and opening up, with the rapid development of China's economic construction, in order to meet the rapid development needs of China's transportation, since the 1980s, China has planned to introduce all kinds of advanced models from developed countries, and all kinds of foreign advanced medium and heavy-duty trucks have also been introduced. At the same time, China's big automobile factories cooperate with famous foreign automobile companies to introduce advanced foreign automobile production technology, including the production technology of automobile gears. At the same time, the level of iron and steel smelting technology in our country is also constantly improving. By adopting advanced smelting technology such as ladle secondary smelting, composition fine tuning, continuous casting and rolling, the steel plant can produce gear steel with high purity and narrow hardenability, thus realizing the localization of imported steel for automobile gear wheel, and making the production level of gear steel in our country to a new level. High hardenability steel containing nickel for gears of domestic heavy-duty vehicles, which is suitable for China's national conditions, has also been applied and achieved good results. The heat treatment technology of automobile gear has also developed from well gas carburizing protection in the 1950s-1960s to computer-controlled continuous gas carburizing automatic line, box type multi-purpose furnace and automatic production line (including low pressure (vacuum) carburizing technology), gear carburizing pre oxygenation technology, gear quenching control cooling technology (due to special quenching oil and quenching cooling technology Isotherm Normalizing Technology of gear forging blank, etc. The adoption of these technologies not only effectively controls the distortion of gear carburizing and quenching, improves the accuracy of gear processing, and prolongs the service life, but also meets the needs of large-scale production of modern heat treatment of gears.

The related literature points out that the service life of automobile gears is mainly evaluated by two indexes, one is the contact fatigue strength of gears, the other is the bending fatigue strength of gears. The former is mainly determined by carburizing and quenching quality, and the latter is mainly determined by gear material. Therefore, it is necessary to have a comprehensive understanding of the requirements, properties and heat treatment characteristics of carburizing steel for automobile gears.