1. Pressure difference between the inside and outside of the reducer: During the operation of the reducer, the friction and heat of the motion pair and the influence of the ambient temperature increase the temperature of the reducer. If there is no vent or clogged vent, the pressure inside the machine will gradually increase. The higher the internal temperature, the greater the pressure difference with the outside, and the lubricating oil will leak from the gap under the action of the pressure difference.
2. The structure design of the reducer is unreasonable
1) The inspection hole cover is too thin, and it is easy to deform after tightening the bolts, making the joint surface uneven and leaking oil from the contact gap;
2) During the manufacturing process of the reducer, the castings are not subjected to annealing or aging treatment, and the internal stress is not eliminated, and deformation will inevitably occur, resulting in gaps and leakage;
3) There is no oil return groove on the box body, and the lubricating oil accumulates in the shaft seal, end cover, joint surface, etc., and leaks from the gap under the action of the pressure difference;
4) The shaft seal structure design is unreasonable.Early reducers mostly used oil groove and felt ring type shaft seal structure, which caused the felt to be compressed and deformed during assembly, and the joint surface gap was sealed.If the contact between the journal and the seal is not ideal, the seal will fail in a short time due to the extremely poor compensation performance of the felt.Although there are oil return holes on the oil ditch, it is very easy to be blocked and the oil return effect is difficult to play.
3. Too much lubricating oil: During the operation of the reducer, the oil pool is greatly agitated, and the lubricating oil splashes everywhere in the machine. If the lubricating amount is too much, a large amount of lubricating oil will accumulate on the shaft seal, joint surface, etc. Cause a leak.
4. Improper maintenance process: During equipment maintenance, oil leakage will also occur due to incomplete removal of dirt on the joint surface, improper selection of sealant, reverse installation of seals, and failure to replace seals in time.