About bearing grease
The grease used in rolling bearings consists of a lubricant and a thickener and also contains a certain amount of peptizer and additives. Lubricants are the main body of lubrication, mainly mineral oil, such as spindle oil, cylinder oil and so on. In addition to thickening, the thickening agent also has a certain lubricating effect, mainly fatty acid salts (soap base), such as calcium soap, sodium soap and the like. A peptizing agent is used to improve the state of fusion between the soap base and the oil body. Additives such as graphite, molybdenum disulfide, etc., can improve the properties of the grease.
(1) Dropping point. That is, the temperature at which the first drop is started after the grease is heated. It indicates the heat resistance of the grease. The maximum working temperature of each grease should be 20~30 °C lower than the dropping point.
(2) Penetration. The depth at which a certain weight of a conical hammer falls into the grease at a certain temperature for 5 seconds is the penetration of the grease, which indicates the viscosity of the grease. If the penetration is too small, the grease is too hard and it is not easy to completely fill the friction surface; if the penetration is too large, the grease is too soft and oil leakage is likely to occur. When using grease, consider the conditions of use, such as environmental conditions, operating temperature, motor speed, etc. When the ambient humidity is high, the grease with strong water resistance should be used. When the bearing speed is high, the grease with weak consistency should be used to avoid the large friction loss in the grease at high speed and increase the bearing temperature rise. And the efficiency of the motor is reduced.