What is the reason for the deterioration, loss and blackening of lithium-based grease?
August 29, 2022
What are the reasons for the deterioration and loss of lithium-based grease and the blackening of extreme pressure lithium-based grease? Many people have doubts about this issue. Let us take a look today so that everyone can understand.
In the case of motor failure, many failures are caused by the deterioration and loss of lithium-based grease; mildly manifested as bearing noise, severe bearing dispersion may lead to motor drilling or burning of windings; in the process of dissecting the faulty motor, at least it can be found One of the following symptoms: dry grinding condition of bearings or lack of oil; oil turns black and agglomerates; bearings have obvious mechanical or electrical corrosion damage; motors with these problems manifest as bearing noise in the early stage of failure; The problem may be attributed to the quality of the bearing, naturally ignoring the influence of grease and its related factors.
Reasons for grease deterioration:
The main reason for the deterioration of the grease is that the bearing heat is higher than the operating temperature of the grease, especially the motor running in the high temperature environment. Bearing heating and oil degradation failure are directly related to two factors. Bearing heating to a certain extent will lead to oil degradation, and oil degradation will aggravate bearing heating. The grease running in the bearing is damaged by mechanical forces that break up and shorten the fibers of the thickener, reducing the ability to maintain the structure of the grease, i.e. consistency changes. If the consistency varies widely, it will run off the work surface. At the same time, during operation, the grease is affected by the increase in temperature. Due to the colloidal damage of the grease, the Base Oil will evaporate or part of the base oil will be lost, thereby reducing the oil content of the grease and possibly oxidative deterioration.
What is the reason for the blackening of extreme pressure lithium grease? 1. Black extreme pressure lithium grease means it has been oxidized and deteriorated. If it's just the surface, the oxidized area can be removed and it can still be used as usual. If it turns red, it means the oil is still alkaline; if it doesn't change colour, it means the oil is sour. In general, grease should not be used on expensive equipment to avoid corrosion, but can be reduced in standard use and used to corrode rough equipment. 2. The filming of extreme pressure lithium-based greases is also due to the oxidation reaction of greases, especially greases made from dry vegetable oils, which can easily occur. The processing method is the same as above. 3. Oil recovery indicates that the stability of the colloid has been destroyed. Slight oil extraction can remove surface oil, and most of the rest can still be used; but try not to use it in high temperature and high load parts. Products that consume heavy fuel should not be used. 4. Emulsification occurs easily when oil absorbs or seeps into rainwater. Slightly emulsified, it can still be used after removing spoiled parts. 5. If the extreme pressure lithium-based grease becomes thin, it may be caused by the storage temperature being too high. If the concentration cannot be recovered, the pH may change and then no longer be used. 6. One of the reasons for long-term freezing and oil hardening is long-term freezing. It can be stored for a period of time at a slightly higher room temperature (such as 30-40 ° C) and restored to its original state. The above is the introduction to this issue. The above phenomena must be paid attention to during use. Only by ensuring the quality of lubricating grease can it effectiv
