ASTM D1478-20

5.1 This test method was developed using greases having very low torque characteristics at −54 °C (−65 °F). Specifications for greases of this type commonly require testing at this temperature. Specifications for greases of other types can require testing at temperatures from −73 °C to −18 °C (−100 °F to 0 °F).

5.2 This test method has proved helpful in the selection of greases for low-powered mechanisms, such as instrument bearings used in aerospace applications. The suitability of this test method for other applications requiring different greases, speeds, and temperatures should be determined on an individual basis.

5.3 Test Method D4693 may be better suited for applications using larger bearings or greater loads. However, greases having such characteristics that permit torque evaluations by either this test method or Test Method D4693 will not give the same values in the two test methods (even when converted to the same torque units) because the apparatus and test bearings are different.

1.1 This test method covers the determination of the extent to which a grease retards the rotation of a slow-speed ball bearing by measuring starting and running torques at low temperatures (below −18 °C (0 °F)).

1.2 The values stated in SI units are to be regarded as standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.