Cause analysis of oil leakage of reducer

1. Pressure difference inside and outside the reducer: during the operation of the reducer, the friction and heating of the moving pair and the influence of the ambient temperature increase the temperature of the reducer. If there is no vent or the vent is blocked, the pressure in the reducer will gradually increase. The higher the temperature in the reducer, the greater the pressure difference with the outside, and the lubricating oil will leak out from the gap under the action of the pressure difference.
2. Unreasonable reducer structure design
1) The inspection hole cover plate is too thin, which is easy to deform after tightening the bolts, resulting in uneven joint surface and oil leakage from the contact gap;
2) In the manufacturing process of reducer, the casting is not annealed or aged, and the internal stress is not eliminated, so it is bound to deform and produce gap, resulting in leakage;
3) There is no oil return groove on the box, and the lubricating oil accumulates at the shaft seal, end cover, joint surface, etc., and leaks outward from the gap under the action of differential pressure;
4) The structural design of shaft seal is unreasonable. The early reducers mostly used the oil groove and felt ring shaft seal structure. During assembly, the felt was compressed and deformed, and the gap on the joint surface 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 poor compensation performance of the felt. Although there is an oil return hole on the oil ditch, it is easy to be blocked and the oil return function is difficult to play.
3. Excessive oil filling: during the operation of the reducer, the oil pool is stirred severely, and the lubricating oil splashes everywhere in the reducer. If the oil filling is excessive, a large amount of lubricating oil will accumulate in the shaft seal, joint surface, etc., resulting in leakage.
4. Improper maintenance process: during equipment maintenance, oil leakage will also be caused due to incomplete removal of dirt on the joint surface, improper selection of sealant, reverse installation of seals, untimely replacement of seals, etc.