5.1 The dropping point is useful to assist in identifying the grease as to type and for establishing and maintaining bench marks for quality control. The results are to be considered to have only limited significance with respect to service performance of conventional soap thickeners because dropping point is a static test. Above 200 °C, the dropping point has no correlation with the maximum upper operating temperature of the grease.

5.2 Historical cooperative testing4 on conventional soap-thickened greases indicated ( RR:D02-1164) that, in general, dropping points by Test Method D2265 and Test Method D566 were in agreement up to 200 °C. In cases where results differ, there is no known significance. However, agreement between the manufacturer and purchaser as to test method used is advisable.

1.1 This test method covers the determination of the dropping point of lubricating grease.

1.2 Warning—The dropping point as measured by this test is an artificially corrected number that does not have any bearing on the performance of the grease at elevated temperature. The dropping point as defined by this test method may not correlate with a value of the dropping point as determined by Test Method D566 (ISO 2176).

1.3  This test method uses mercury thermometers. WARNING—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location. The responsible subcommittee, D02.G0.03, continues to explore alternatives to eventually replace the mercury thermometers.

1.4  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.

1.5 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.