Influence of thickener on low temperature performance of grease?
With the rapid development of modern industry and national defense, the operation demand of machinery and equipment in extreme environments is increasing, especially at low temperature conditions, the performance of grease is particularly important. As an indispensable solid lubricating material for the normal operation of mechanical equipment, the low temperature performance of grease is directly related to the start-up, operation efficiency and service life of equipment. As an important part of grease, thickener has a significant effect on the low temperature performance of grease. In this paper, the types and mechanisms of thickeners and their effects on the low temperature performance of greases are discussed.
First, the type and characteristics of thickener
Thickener is a key component in grease that determines its consistency and viscosity. According to chemical structure and performance characteristics, thickener can be divided into many types, mainly including metal soap-based thickener (such as lithium soap, calcium soap), composite metal soap-based thickener (such as composite lithium soap,
Calcium Sulfonate soap), non-soap based thickener (such as bentonite, polyurea) and so on. Each thickener has its own unique performance characteristics:
Metal soap based thickener: such as lithium soap and calcium soap, with good mechanical stability and water resistance, is a commonly used grease thickener. Lithium soap-based grease shows better fluidity at low temperature, while calcium soap-based grease has higher water resistance.
Composite metal soap based thickener: such as composite lithium soap and calcium sulfonate soap, by combining a variety of metal soap, can improve the extreme pressure performance and high temperature performance of the grease to a certain extent, but may have a certain impact on the low temperature performance.
Non-soap-based thickener: such as bentonite and polyurea, this kind of thickener has unique structural characteristics, can maintain good stability at different temperatures, but compared with metal soap-based thickener, its low temperature performance may be slightly inferior.
