ASTM D892 standard test method for foaming characteristics of lubricating oils
4. Summary of Test Method
4.1 The sample, maintained at a temperature of 24°C (75°F) is blown with air at a constant rate for 5 min, then allowed to settle for 10 min. The volume of foam is measured at the end of both periods. The test is repeated on a second sample at 93.5°C (200°F), and then, after collapsing the foam, at 24°C (75°F).
5. Significance and Use
5.1 The tendency of oils to foam can be a serious problem in systems such as high-speed gearing, high-volume pumping, and splash lubrication. Inadequate lubrication, cavitation, and overflow loss of lubricant can lead to mechanical failure. This test method is used in the evaluation of oils for such operating conditions.
