In recent years, with the development of equipment manufacturing industries such as transportation, aviation and construction machinery, the total amount of global gear industry is more than 100 billion US dollars every year. China is a big country in gear manufacturing. High end bevel gear products such as industrial RV (rotate vector) reducer, automobile automatic transmission and high-speed high-speed rail device rely heavily on imports, with a large trade deficit. Bevel gear is the most widely used transmission component in modern industrial field. Its transmission system has the advantages of compact structure, stable operation, high power, high reliability, constant transmission ratio and so on. At present, the research of bevel gear focuses on high speed, high precision, high service life, low cost, light weight and so on. The 13th five year plan for the development of the gear industry points out that in order to become a powerful country in the equipment manufacturing industry, China must first become a powerful country in the manufacturing of basic parts represented by bevel gears. Upgrading the industries of basic parts such as bevel gears is conducive to improving the core competitiveness of the equipment manufacturing industry.
In the field of automobile bevel gear, the competition in China’s automobile market is becoming increasingly fierce, and the requirements for the quality of automobile gears are higher and higher. In terms of process level, production efficiency and average energy consumption, there is still a big gap between China’s automobile gears and developed countries.
To improve the quality of automobile bevel gear, it is necessary to upgrade the heat treatment process of automobile bevel gear and develop energy-saving and environmental protection technologies such as dual frequency induction heating and quenching. In the field of high-end aviation bevel gear, with the development of aviation industry, the working condition of bevel gear is more complex and the load is increasing, which puts forward higher requirements for the quality and reliability of aviation bevel gear. In the field of construction machinery, most parts fail due to excessive surface wear. The wear resistance of bevel gear is poor, and its surface accuracy is easy to decline when working, which affects the normal operation of the whole equipment. The statistical analysis results of the Japanese mechanical society show that about 74% of the bevel gear pair failures are caused by fatigue failure. Improving tooth surface strength, wear resistance and reducing stress concentration are helpful to improve the quality and service life of bevel gear.
At present, China is moving towards a powerful manufacturing country, and the manufacturing industry is developing in the direction of resource-saving and environment-friendly. Made in China 2025 clearly proposes green transformation and upgrading of traditional manufacturing industries such as iron and steel, strengthen the research on energy-saving and environmental protection technologies and processes in manufacturing industry, and improve the utilization rate of manufacturing resources. Due to the low carbon emission, high strength, small distortion and high wear resistance of induction heating technology, the Japan heat treatment association takes induction heating technology as one of the three development routes in the development route planning of metal heat treatment. The 13th five year development plan of heat treatment in China also clearly puts forward the development of high hardness clean heat treatment surface hardening technology, and the research on the zero deviation precision heat treatment technology of bevel gear. Its main contents include the research on the stress formation mechanism of bevel gear induction quenching process, the research on the new multi frequency induction heating quenching process, etc.