The needs for gear processing of vehicles and tractors are more strict as the operating circumstances of automotive and tractor gears are more complicated than those of machine tool gears. The particular requirements are indicated as follows, for reference only.
1. It calls more wear resistance, fatigue strength, core strength, and impact toughness than machine tool gears.
2. Usually utilised is low-carbon alloy steel (20MnMoB, 20SiMnVB, 30CrMnTi, etc.), carburised, quenched and tempered at low temperature because the load and impact are significant.
3. The delivery The final gearbox gear of the tractor has a high torque; the unit pressure of the tooth surface is high; the sealing is not excellent; the sand and ash are easy to drill in; the working circumstances are very bad; and carburising such as 20CrNi3A is usually employed.
