Lubricating oils are not completely free of air. Whether during operation or storage in barrels, oils are constantly in an exchange process with their air-containing environment. Even if the oil is free of air bubbles, it will have a proportion of dissolved air. This depends primarily on the gas solubility, but pressure and temperature also have an effect. Some mineral oils can have air content approaching 9 to 11 percent volume at atmospheric pressure and room temperature. As long as the air remains dissolved in the oil, this generally is not a problem. Table 1. Comparison of…
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How to Prevent Foaming and Air Dispersions in Industrial Gear Oils
