Lubrication of agricultural gearbox

Commonly used gearbox lubrication methods include gear oil lubrication, semi-fluid grease lubrication, and solid lubricant lubrication. For better sealing, high speed, high load, good sealing performance can be lubricated with gear oil; for poor sealing, low-speed can be lubricated with semi-fluid grease; for oil-free or high-temperature applications Molybdenum sulfide superfine powder lubrication.

The lubrication system of the gearbox is very important for the normal operation of the gearbox. The large wind turbine gearbox must be equipped with a reliable forced lubrication system to inject the oil to the gear meshing area and bearings. In the cause of the failure of the gearbox, the lack of lubrication accounted for more than half. Lubricating oil temperature is related to component fatigue and overall system life. Generally speaking, the maximum oil temperature of the gearbox should not exceed 80 °C during normal operation, and the temperature difference between different bearings should not exceed 15 °C. When the oil temperature is higher than 65 °C, the cooling system starts to work; when the oil temperature is lower than 10 °C, the oil should be heated to the predetermined temperature and then turned on.

In the summer, due to the long-term full state of the wind turbine, plus direct sunlight, the operating temperature of the oil rises above the set value; while in the cold winter in the northeast, the minimum temperature often reaches below 30 °C, lubrication. Lubricating oil in the pipeline is not smooth, gears and bearings are not fully lubricated, causing the gearbox to stop at high temperature, the tooth surface and bearing are worn out, and the low temperature will also increase the viscosity of the gearbox oil. When the oil pump starts, the load is heavy and the pump motor is overloaded.

Gearbox lubricants have an optimum temperature range for operation. It is recommended to design a lubricant thermal management system for the gearbox lubrication system: when the temperature exceeds a certain value, the cooling system starts to work. When the temperature is lower than a certain value, the heating system starts to work. Always keep the temperature within the optimal range. In addition, improving the quality of lubricating oil is also an important aspect that must be considered in the lubrication system. Lubricant products must have excellent low-temperature fluidity and high-temperature stability, and research on high-performance lubricating oil should be strengthened.