Water separbility – how well your oil sheds water.

Water Separability (120ml)There are 3 or 4 main methods to choose from when determining an oils tendency to mix and separate from each other with the principle of timing how long the fluids take to separate. Some methods simply time the separation, whilst others measure the level of emulsion in the fluid too. LearnOilAnalysis recommends the ASTM D1401 method in which 40ml of the fluid and 40ml of water are heated to 50OC and mixed using a high speed agitator for 5 minutes until a milky emulsion if formed. The sample is then timed every 5 minutes to determine the level of separation, if at 1 hour the fluid has not separated then the test is stopped and the values are reported to the client. The result is quoted as ml of oil – ml of water – ml of emulsion (time in minutes to reach this point), e.g. 40-40-0 (5) means the oil fully separated in 5 minutes, whereas 30-10-40 (60) means there is 30ml of water, 10 ml of water and 40 ml of water at the 60 minute mark. As mentioned there are other methods e.g. IP19, so please contact us if you would prefer we use a different method on your samples.

Tested On: Turbines, but also any product where the separation of water and oil needs to be measured.

Diagnostic significance & Typical diagnostic limit: This is particularly useful in conjunction with monitoring water content and rust characteristics of the oil. A typical diagnostic limit is set as the oil does not fully separate within 20 minutes. If water in the system cannot be removed, then it is critical to implement measures to reduce water ingress into the system.