1. Gearbox motor During the operation, the temperature of the gearbox will increase due to the frictional heating of the movement pair and the influence of the ambient temperature. If it is blocked, the internal pressure of the machine will gradually increase. The higher the temperature inside the machine, the greater the pressure difference with the outside world, and the lubricant will leak out of the gap under the effect of the pressure difference;

　　2. There is no oil return groove on the box. The lubricating oil accumulates at the shaft seal, end cover, joint surface, etc., and leaks out from the gap under the pressure difference;

　　3. If the journal is not in perfect contact with the seal, the seal will fail in a short time due to the poor compensation performance of the felt. Although there is an oil return hole in the oil ditch, it is very easy to be blocked and it is difficult to exert the oil return effect.

　　4. Excessive amount of fuel: During the operation of the reducer, the oil pool is agitated very much, and the lubricant splashes everywhere in the machine. If the amount of fuel is excessive, a large amount of lubricant will accumulate on the shaft seal, joint surface, etc , Causing leakage.

　　5. Improper maintenance process: During equipment maintenance, due to incomplete removal of dirt on the joint surface, or improper selection of sealant, reverse installation of seals, and failure to replace seals in a timely manner may also cause oil leakage.