Colloidal stability of grease:
The ability of grease to retain oil in the thickener's skeleton under the action of external forces is called colloidal stability. Lubricating grease is a kind of colloidal dispersion system. The stability of its colloidal structure is often affected by temperature and pressure and is damaged to varying degrees, resulting in separation of the lubricating oil in the fixed soap fiber space skeleton. However, if the grease cannot separate a part of the lubricating oil under the working pressure, it will not be able to function as a lubricant. Therefore, there should be moderate requirements for the oil separation performance of the grease, neither too large nor too small.
The colloidal stability of the grease is related to the viscosity of the grease base oil. The viscosity of the base oil is small, the colloidal stability of the grease is poor, it is easy to separate oil, and the amount of oil is also large. The grease contains too much free base, and the grease has a large amount of oil. The packaging container of the grease is too large, and the skeleton of the grease thickener is easily damaged and the oil is easily separated out under the action of gravity. In addition, the grease will also cause oil separation due to the centrifugal force during use. Bearing experiments show that when the oil loss in the grease reaches 50%, the bearings used are burned out. Shanghai Lubricants