Foshan Pearl River Reducer: Reducer oil leakage reason analysis

Release time:

Sep 14,2022

  Foshan the Pearl River reducer manufacturer said that the reducer is generally used for transmission equipment with low speed and high torque. A high-speed motor, internal combustion engine, or other power source achieves the purpose of deceleration by meshing the smaller gears on the input shaft of the reducer with the larger gears on the output shaft. A regular gearbox also has several pairs of gears with the same principle to achieve the desired deceleration effect. The ratio of teeth between large and small gears is the transmission ratio.

  Maintenance of the gearbox:
  The manufacturer of the Pearl River gear reducer in Foshan said that when selecting the grease according to the bearing load of the traveling gear reducer, the grease with small penetration should be selected for heavy load. When working under high pressure, in addition to low needle penetration, high oil film strength and extreme pressure function are also required. Calcium based lubricating grease has good water resistance and is not easy to emulsify or deteriorate when exposed to water. Can be used for lubrication of various mechanical parts in humid environments or in contact with water. When selecting lubricating grease based on working temperature, the main indicators should be drip point, oxidation stability, and low-temperature function. Dropping points can generally be used to evaluate high-temperature functionality, and the actual operating temperature of bearings should be 10-20 ℃ lower than the drop point. The usage temperature of synthetic lubricating grease should be 20-30 ℃ lower than the drop point.
The manufacturer of the Pearl River gear reducer in Foshan said that different lubricants are prohibited from mixing with each other. The position of the oil level plug, drain plug, and vent hole is determined by the installation position.

Analysis of the causes of oil leakage in the gearbox:
​​​​​​​  1. Differential pressure inside and outside the reducer: During the operation of the reducer, the friction and heating of the moving pair, as well as the influence of environmental temperature, cause the temperature of the reducer to increase. If there are no pores or pores are blocked, the pressure inside the machine will gradually increase. The higher the internal temperature of the machine, the greater the pressure difference with the outside world, and lubricating oil will leak out of the gaps under the action of the pressure difference.
​​​​​​​  2. The structural design of the reducer is unreasonable.
​​​​​​​  1) The inspection hole cover plate is too thin, which is prone to deformation after tightening the bolts, resulting in uneven joint surfaces and oil leakage in the contact gap;
​​​​​​​  2) During the manufacturing process of the reducer, if the casting is not annealed or aged, and the internal stress is not eliminated, it will inevitably lead to deformation, gaps, and leakage;
​​​​​​​  3) There is no oil return groove on the box, and lubricating oil accumulates in the shaft seal, end cover, joint surface, etc., which leaks out from the gap under the pressure difference;
​​​​​​​  4) The design of the shaft seal structure is unreasonable. The manufacturer of the Pearl River gear reducer in Foshan said that in the early years, the gear reducer used oil groove and felt ring shaft seal structure, which made the felt compressed and deformed during assembly and sealed the joint surface gap. If the contact between the shaft neck and the seal is not ideal, the seal will fail in a short period of time due to the poor compensation performance of the felt. Although there are oil return holes in the oil tank, they are prone to blockage and the oil return function is difficult to play.
​​​​​​​  3. Excessive oil filling: When the gearbox is running, the oil pool is stirred severely, and lubricating oil splashes everywhere in the machine. If there is excessive oil injection, a large amount of lubricating oil will accumulate on the shaft seal and joint surface, causing leakage.
​​​​​​​  4. Improper maintenance process: During equipment maintenance, incomplete removal of dirt from the joint surface, improper selection of sealant, reversed sealing, and failure to replace the seal in a timely manner may also cause oil leakage.