Does grease have a shelf life?

As We All Know That People eat food, machines eat oil, but the common point is: fresh is better. What effect does storage condition have on lubricating oil? What measures can help maintain the performance of lubricating oil? What should be done before using lubricating oil that has been stored for too long? These issues are very important for industrial production.

Everything has a shelf life, but the shelf life cannot be found on the packaging of lubricating oil and grease. Deteriorated lubricating oil is harmful to the machine, so the storage time of lubricating oil and whether it deteriorates are issues worth discussing.

Lubricating oil failure = machine failure. The performance of lubricating oil is relatively stable. As long as it is stored properly, it generally does not affect the use. Therefore, the state does not stipulate the shelf life or validity period of lubricating oil. Under normal storage conditions of room temperature sealing state and dryness and protection from dust, water and chemical smoke, the oil is stored for more than three years, and the various indicators will basically not change. Despite this, users should pay special attention to storage conditions, because in reality, the storage conditions of lubricating grease are not always ideal, and the speed of lubricating oil deterioration is largely affected by storage conditions.

When in contact with air, lubricating oil will oxidize, and certain factors will accelerate the oxidation process, causing the lubricating oil to "age prematurely". The types of base oil and additives will affect the oxidation rate of lubricating oil. Grease will oxidize faster because thickeners are added. However, the factor that has the greatest impact on the storage of lubricating oil is the storage environment conditions. During storage, the oxidation rate doubles for every 10 degrees Celsius increase in temperature (that is, the shelf life of the lubricating oil is halved). In addition, large temperature differences and large temperature changes are also prone to produce water, which will cause the lubricating oil to deteriorate.

Lubricating oil should avoid frequent stirring during storage, because it is easy to bring air into the oil, causing the upper layer of oil to be oxidized. Agitation is also easy to cause oil emulsification. The storage container of lubricating oil also affects the oxidation rate of lubricating oil. For example, iron containers in contact with oil will accelerate the oxidation of lubricating oil, so adding a layer of lining that is not easy to react (such as plastic) solves this problem.