The Effect of Hydrolysis on Grease Performance

The Effect of Hydrolysis on Grease Performance

Apr 19th 2024

Greases and oils are the lifeblood of heavy equipment, ensuring efficiency, longevity, and safety. Yet, for all their role in the day-to-day operation, the performance of these lubricants is not as immutable as we might assume. Hydrolysis can undermine the function of grease, leading to catastrophic failure. Explore the effect of hydrolysis on grease performance and strategies for combating its detrimental effects.

Understanding Hydrolysis

Hydrolysis, derived from the Greek words for “water” and “loosening,” involves the breaking down of chemical bonds in a substance due to a reaction with water. In the context of lubricants, this can occur in the complex compounds that constitute grease. When exposed to water, these compounds can break down into simpler forms, diminishing the performance of the lubricant.

Hydrolysis and Grease: The Perfect Storm

The presence of water in a lubricating environment is inevitable. Most grease applications will face some degree of water exposure, whether from external sources or internal condensation. When water intrudes, it can interact with the thickener—the component that gives grease its consistency—and the base oil. Over time, these interactions can lead to several changes:

Saponification of Grease

Saponification occurs when a fat or oil reacts with an alkali to produce soap and glycerol. When water interacts with metal soap, the most common type of grease thickener, it can produce more water-insoluble soap. While this might sound like a good thing due to the creation of additional lubricant, it disrupts the grease’s gel structure and causes it to soften and lose its consistency.

Viscosity Breakdown

Water contamination can also reduce oil viscosity, a key indicator of a lubricant’s ability to coat and protect surfaces. A lower viscosity means the oil is less capable of withstanding the mechanical stresses and high temperatures within machinery. This can result in increased friction and wear, leading to premature equipment failure.

Acid Number Increase

The acid number measures the amount of acidic substances in a sample. In the case of grease, they usually arise from oxidation or hydrolysis. A high acid number indicates an increase in acidity, which can lead to corrosion of metal components. It can also accelerate the degradation of the base oil, reducing its ability to provide lubrication.

Combatting Hydrolysis: Strategies for Longevity

Given the potentially catastrophic consequences of hydrolysis on grease performance, it is essential to implement preventative measures against it. By using water-resistant greases, monitoring moisture levels, and choosing the right grease for your needs, you can ensure your lubricant lasts and avoid issues associated with hydrolysis. If you use aviation lubricants, these strategies will help you preserve the quality of your machinery.

Discover Peak Efficiency

As we continue to push the boundaries of grease performance, understanding and managing the effect of hydrolysis is critical for maintaining smooth operations. By incorporating hydrolysis awareness into your practices, you can protect your machinery and usher in innovation.