What are the basic requirements for the performance of large diameter load gears?

(1) Basic requirements According to the working conditions of the gear, the following basic requirements should generally be met:

1) The surface layer of the gear teeth should have sufficient hardness and wear resistance;

2) For gears that bear alternating load and impact load, the base should have sufficient bending resistance and toughness;

3) Good process performance, easy cutting and good heat treatment performance.

High-speed and heavy-duty gears have become the key components of complete sets of equipment in the automobile and locomotive industry. Most of them use hard-tooth surface wheels. The peripheral speed of the gears can reach up to 150 m/s, the transmission power can reach up to 40000kW, and the accuracy level of the gears can reach 5~6. The highest is level 4. At present, it has designed and manufactured high-speed gears with a maximum power of 44000kW, a high circumferential speed of 156 m/s, and a gear manufacturing accuracy of 4~5 grades. Heavy-duty gears have a maximum power of 600kW, a maximum transmission torque of 2000kN · m, a circumferential speed of 30~50 m/s, and a gear accuracy of 5~6 grades.

(2) large gear large gear in metallurgy, mining, building materials, lifting, transportation and other heavy machinery transmission occupies a heavy position. The hard tooth surface large gear can reduce the power required for transmission, increase the carrying capacity, reduce the cost and improve the service life.

Generally, large gears bear heavy loads when working, and have high requirements for tooth surface wear resistance, tooth root fatigue strength, tooth surface contact part corrosion and tooth top strength. These properties are closely related to the hardness, strength and deformation of the hardened layer after gear quenching.