1. Pressure difference between inside and outside reducer

During the operation of the reducer, the friction heating of the moving pair and the influence of the ambient temperature make the temperature of the reducer rise. If there is no blockage of the air permeability hole or the air permeability hole, the pressure inside the reducer will gradually increase. The higher the temperature inside the reducer, the greater the pressure difference between the outside and the outside, and the lubricant will leak out from the gap under the pressure shyness.

2. The unreasonable design of reducer structure1. The cover plate of the inspection hole is too thin. It is easy to deform after tightening the bolt, which makes the joint uneven and leaks oil from the joint.2. In the manufacturing process of decelerator, the castings are not annealed or aged, so the internal stress of the castings is eliminated by the beam. Deformation will inevitably occur and the castings will be gapped, which will lead to leakage.

3. There is no oil return groove on the box body, and the lubricating oil is confined to the shaft seal, end cover, joint surface, etc. Under the action of pressure difference, it leaks out from the clearance.

4. The design of seal structure is unreasonable. Early reducers mostly used oil ditch and felted ring type shaft seal structure. When assembled, the felt was compressed and deformed, and the joint gap was sealed. If the contact between journal and seal is not ideal, the sealing will fail in a short time because of the poor compensation performance of felt. Although there are oil return holes on the oil ditch, it is easy to block up and the oil return function is difficult to play.

OverfillingDuring the operation of the reducer, the oil pool is stirred badly, and the lubricating oil splashes everywhere in the reducer. If the amount of oil is too much, a large amount of lubricating oil accumulates in the shaft seal, joint surface and other places, leading to leakage.

Improper overhaul technologyOil leakage will occur when the equipment is overhauled due to incomplete removal of dirt on the joint surface, improper selection of sealant, reverse direction of seals, and failure to replace seals in time.