Roll stability apparatus used for shear stability tests on lubricating greases. The device simulates the effect of squeezing grease between the rollers and the outer ring raceway of roller bearings.
Each test cylinder contains a heavy roller and is filled with a certain quantity of the sample grease. The RST allows up to four test cylinders to be used simultaneously. The test cylinders rests horizontally upon a set of driving and guide wheels which rotate the cylinders.
The test method provides an indication of shear stability of lubricating greases by testing the change in worked penetrations after two hours in the roll stability tester.
This apparatus conforms to ASTM D1831 and related specifications.