What is a good operating temperature range for grease? The maximum or minimum service temperature of grease is often referred to as the extreme temperature. Under extreme temperature conditions, the performance of lubricating grease is often far from its initial performance, often causing problems such as insufficient lubrication, or even failing to meet the lubrication needs. Therefore, it is necessary to determine the service temperature range of a grease that can meet the lubrication needs. The Swedish SKF Group (SKF) proposed the concept of dual traffic lights, and gave the definitions of low temperature limit, low temperature performance limit, high temperature performance limit and high temperature limit:
1. Low temperature limit: the lowest temperature at which the grease allows the bearing to start easily;
2. Low temperature performance limit: Below this temperature limit, the supply of grease on the contact surface of rolling elements and rings may be insufficient;
3. High temperature performance limit: above this temperature limit, the grease will oxidize in an uncontrolled manner, so the service life of the grease cannot be accurately determined;
4. High temperature limit: When the temperature limit is exceeded, the grease will lose its stable structure (such as the dropping point of soap-based grease) for a long time.
Definition hint: the lubricating grease should avoid working below the low temperature limit temperature or exceeding the high temperature limit temperature, otherwise the lubricating grease will not be able to provide reliable lubrication, and a warning red should be marked at this time; if the grease is near the low temperature performance limit and high temperature performance limit If the grease is working at a temperature above 100, it should be marked yellow, indicating that the service life of the grease will be shortened at this time.
The good operating temperature ranges of some common mineral oil greases are shown in the table below:
