An Overview of Grease Water Resistance

Many grease-lubricated components operate in wet environments, making them susceptible to water contamination which degrades their performance, functionality, and useful life. Hence, selecting a grease with appropriate water-resistant properties can have a significant influence on the life of the machine. While industry standards attempt to evaluate a grease’s water resistance, research indicates that a more thorough understanding of water resistance is needed to properly match a grease to an application. This paper provides an overview of the interaction of grease and water, covers existing water-resistance standards, discusses the results of available experiments aiming to describe the effects of water on grease, demonstrates the need for more meaningful standards, and suggests additional measures for characterizing a grease’s water resistance.