Is the presence of air considered a contaminant that impacts lubricant performance?

The presence of air is indeed considered a contaminant that can significantly impact lubricant performance. When air is introduced into a lubrication system, it can lead to several detrimental effects. One of the primary issues is the formation of oxidation products, which occur when the lubricant reacts with oxygen in the air. This oxidation can lead to the breakdown of the lubricant, decreasing its effectiveness and potentially causing the formation of sludge and varnish, which can impede machine performance.

Moreover, air can also create problems such as foam formation, which reduces the lubricant's ability to maintain a proper film strength and protect surfaces from wear. Foam can lead to an inconsistent lubrication supply, resulting in insufficient protection for moving parts and potentially causing damage.

In addition to these chemical and mechanical issues, the presence of air can also lead to cavitation in hydraulic systems, where bubbles collapse and create shock waves that can erode surfaces and cause further damage. Overall, the entry of air into a lubrication system can have multiple negative consequences for lubricant efficacy and machine reliability. Thus, understanding and managing the presence of air as a contaminant is critical for maintaining optimal lubrication performance.