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Why does the planetary gearbox leak oil?

Have you ever encountered the situation where a planetary gearbox leaks oil? Do you know what caused it? Many users have experienced the problem of oil leaks during usage; what causes this? The following are the key causes. 

The planrtary gearbox works according to the principle that the original motor is connected to the reduction gearbox, and the reduction gearbox is then connected to the working machine. It is a kind of power transmission equipment, the main purpose is to reduce the output of the motor or increase the output of the motor. But many people have encountered the phenomenon of oil leakage in the process of use, what causes this? We mainly summarize the following reasons.

  1. The pressure inside the oil tank rises
  2. In the closed reducer, each pair of gear meshing friction will give off heat, according to Boyle's law, with the lengthening of the running time, so that the temperature inside the reducer box gradually rises, and the volume of the reducer box remains unchanged, so the pressure inside the box increases, and the lubricant inside the box by splashing, spilling in the inner wall of the reducer box. As the oil permeability is relatively strong, under the pressure in the box, where the seal is not tight, the oil will seep out from there.
  3. Oil leakage caused by unreasonable design of reducer structure
  4. If the design of the reducer does not have a ventilation cover, the reducer cannot achieve equal pressure, which will cause the pressure inside the box to become higher and higher, and eventually, oil leakage will occur.
  5. Excessive refueling
  6. During the operation of the reducer, the oil pool will be stirred violently, and the lubricant will splash everywhere in the machine. If the amount of oil is too much, a large amount of lubricant will accumulate in the shaft seal, bonding surface and other places, which will eventually lead to leakage.
  7. Improper inspection process
  8. In equipment maintenance, due to the combination of surface dirt removal is not complete, improper selection of sealant, the direction of the seal being installed backward, not a timely replacement of seals, etc. will also cause oil leakage.

How to deal with transmission oil leakage?

  1. Improvement of ventilation cap and inspection hole cover
  2. Improvement of the shaft seal structure
  3. The use of new sealing materials
  4. Regular and careful maintenance
  5. Improvement of machining accuracy and factory quality control, use of better parts


If you also encounter the phenomenon of oil leakage in the process of using Planetary gear motor , you just need to find the cause of your reducer leakage, and then according to this reason improve it.

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