LUBRICATING GREASES ANALYSIS: ASTM D128
These test methods cover conventional greases that consist essentially of petroleum oil and soap. Thus these test methods are applicable to many but not all greases. Composition should not be considered as having any direct bearing on service performance unless such correlationship is established. The constituents covered by these test methods are soap, unsaponifiable matter (petroleum oil, etc.), water, free alkalinity, free fatty acid, fat, glycerin, and insolubles.
A supplementary test method is also provided intended primarily for application to greases containing thickeners that are essentially insoluble in n-hexane, and to greases that cannot be analyzed by conventional methods because of the presence of such constituents as non-petroleum fluids or non-soap type thickeners, or both.
No round robins have been completed to obtain precision and bias data.
