What is it?
The demulsification rig enables easy differentiation of demulsification properties of lubricants. This is vital for certain applications where water within the oil phase can lead to corrosion, wear and other related lubrication problems.
Why do we use it?
The demulsification rig is used to mix oil and water together and determine the point at which the mixture or formed emulsion breaks into two phases at a fixed temperature. The longer it takes for the two phases to form translates to a poorer performance in demulsification.
How does it work?
Equal volumes (40 ml) of oil and water are added to a graduated measuring cylinder and allowed to reach the test temperature in the water bath.
It is then mixed for 5 minutes using a paddle mixer of specific dimensions at 1500 rpm. Once 5 minutes has passed the emulsion is left to stand at the test temperature. The volumes of oil, water and mixed / emulsion are recorded every 5 minutes for a maximum of 30 minutes. The visual characteristics of the emulsion are also recorded. The test is considered a pass if the volumes of the oil and water phases are 40 ± 3 ml within 30 minutes and the emulsion phase is ≤ 3 ml.
The temperature at which the test is run depends on the viscosity of the oil being tested.
This test is described in the standard test method ASTM D1401 and results can be seen below.
Typical Test Conditions:
Water Bath Temperature
Oil Viscosity (cSt) : <90 | ≥90
Temperature (°C) : 82 | 54
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