First, adhesion. When the friction site is in a static state, the grease can maintain its original shape, will not be automatically lost due to gravity, it will not slide on the vertical surface and leak out from the gap. When the friction part is in motion, the grease will not be thrown off by centrifugal force like oil, and it will not splash out from the poorly sealed part. Some drip or oil splashes can be almost completely avoided, which ensures that the environment is free from or less polluted and also prevents contamination of the product. This is particularly important for industries such as papermaking, weaving, and food.
Second, the use of temperature range. Grease has a wider operating temperature range than lubricating oils. For example, a general-purpose lithium grease can be used at a temperature of -20 to 120°C. In general, a calcium- or sodium-based grease can also be used at -20 to 60°C or -20 to 120°C. However, a certain brand of lubricants uses a much narrower temperature range.
Third, pressure resistance. The grease adsorption capacity on the metal surface is much greater than that of lubricating oil, and it can form a relatively strong oil film and withstand relatively high work load. This is due to the large amount of polar material contained in the grease. In addition, it is used as a base grease, and when the polar additive is added, the sensitivity is also better than that of the lubricant.
Fourth, the service life. When the grease is used for a long time without being replaced, the function of lubrication can still be ensured, because only a small part of the grease which is close to the friction surface is really used for lubrication, and the reliance on the cyclic lubrication of the soap fiber shows that the service life is quite long; Lubricating oils need to be added frequently or recycled, otherwise the normal lubrication of the machinery cannot be guaranteed. In terms of quantity, the consumption of lubricating oil is 15-20 times more than that of grease. Therefore, there are many more parts lubricated with grease than lubricating oil. Such as automotive lubrication, using grease accounts for about 2/3 strong. On the other hand, due to infrequent refueling, the maintenance period is long, consumption is reduced, and maintenance costs are also low.