LOW TEMPERATURE FLUIDITY AND APPEARANCE OF HYDRAULIC FLUIDS: ASTM D6351
EXPLANATION
The temperature at which a lubricant remains fluid and homogenous after seven days is an index of its ability to withstand prolonged exposure to cold temperatures. Quick cool, short term tests such as Test Methods ASTM D97 and ASTM D2500 do not adequately predict the tendency to solidify over long time spans at cold temperatures. This test method covers the fluidity and appearance of hydraulic fluids after storage at low temperatures. This test method, however, is not intended to indicate cold temperature pumpability performance. No specific temperature of measurement is given in this test method because fluids with different viscosity grades have different cold temperature performance expectations.
TEST SUMMARY
The sample is dried to remove trace amounts of water and is then cooled to a specified temperature. After seven consecutive days, the sample is examined for its ability to flow and observed for homogeneity.
TEST PRECISION
Precision data are not yet available.
No statement of bias can be made.
