In oil analysis, what does an increasing Total Acid Number (TAN) typically indicate?

An increasing Total Acid Number (TAN) serves as a significant indicator of oil condition and health. Specifically, a rise in TAN typically signifies that the oil is undergoing oxidation. As the oil oxidizes, it generates acidic byproducts, resulting in a higher TAN value. This is an important parameter to monitor because elevated acidity can lead to detrimental effects on machinery components, including increased wear rates and damage to seals and gaskets.

Oxidation can be accelerated by factors such as elevated temperatures, contamination by moisture or other substances, and prolonged use. Therefore, understanding the implications of TAN helps in implementing appropriate maintenance strategies and ensuring the longevity of equipment. Maintaining a balanced acid level in lubricant oils is critical to ensuring effective performance and reliability in machinery.