4. Summary of Test Method
4.1 A sample of lubricating grease contained in a cup suspended in a test tube is heated in an oil bath at a prescribed rate. The temperature at which material falls from the hole in the bottom of the cup is averaged with the temperature of the oil bath and recorded as the dropping point of the grease.
5. Significance and Use
5.1 In general, the dropping point is the temperature at which the grease passes from a semisolid to a liquid state under the conditions of test. This change in state is typical of greases containing as thickeners soaps of conventional types. Greases containing as thickeners materials other than conventional soaps can, without change in state, separate oil. This test method is useful to assist in identifying the grease as to type and for establishing and maintaining bench marks for quality control. The results are considered to have only limited significance with respect to service performance as dropping point is a static test.
NOTE 1 - Cooperative testing indicates that in general, dropping points by Test Method D5663 and Test Method D2265 are in agreement. In cases where results differ, there is no known significance. However, agreement between producer and consumer as to the test method used is advisable.
