Do lubricants have a shelf life?

People eat, machines eat oil, but the common denominator is: fresh is better. How do storage conditions affect lubricants? What measures help to maintain the performance of lubricants? What should be done before using lubricants that have been stored for too long? These questions are very important for industrial production.

 

Everything has a shelf life, but the shelf life cannot be found on the packaging of lubricants and greases. Deteriorated lubricant is harmful to the machine, so the storage time of lubricant and whether it has deteriorated is an issue worth exploring.

Lubricant failure = machine failure, the performance of the lubricant is relatively stable, as long as the proper storage, generally will not affect the use. Therefore, the state does not specify the shelf life or expiration date of the lubricant. Sealed at room temperature and dustproof, waterproof, chemical fumes in the dry normal storage conditions, the oil stored for more than three years, the indicators will not change. Nevertheless, the user should pay special attention to the storage conditions, because the reality is that the storage conditions of lubricating grease are not always ideal, and the speed of deterioration of lubricating oil is largely influenced by the storage conditions.

 

In contact with air, lubricants oxidize, and certain factors can accelerate the oxidation process, causing lubricants to "age" prematurely. The type of base oil and additives affect the rate of oxidation of the lubricant, with grease oxidizing faster because of the thickening agents added to the grease. However, the biggest influence on the storage of lubricants is still the environmental conditions of storage, storage, the temperature rises every 10 degrees Celsius, the oxidation rate doubled (that is, the shelf life of the lubricant is halved). In addition, the temperature difference is large, the temperature change is also easy to produce water, water will cause lubricant deterioration.

 

Lubricants should be stored in a way that avoids frequent stirring, as it is easy to bring air into the oil, causing the top layer of oil to be oxidized. Stirring also tends to cause oil emulsification. The storage container of the lubricant also affects the rate of oxidation of the lubricant. For example, an iron container in contact with the oil will accelerate the oxidation of the lubricant, so the addition of a liner (e.g., plastic) that is less susceptible to reaction solves the problem.

 

The following is the recommended storage period for some oils, lubricants, grease storage is recommended not to exceed this period, more than this period of oil in the use of oil before it is best to do a fluid testing (oil analysis). Warehouse management of oil should follow the "first in, first out" principle - that is, the first storage of oil should be used first.