Steam emulsification number is the time (in seconds ) required for an emulsion of lubricating oil and water to separate into distinct layers at 900C.
Emulsification is the properly of oil to get mixed with water forming a dispersed phase of oil in water or water in oil, the emulsification property of oils is expressed in terms of stream emulsification number and is determined by A.S.T.M ( American society for testing material) method.
Determination of steam emulsification number
Steam of 1000C is bubbled through 20mL of lubricating oil till its temperature reaches 90 steams 0C When the oil temperature reaches 900C. The time required (in seconds) for water (formed due to condensation of steam) and oil to separate into two distinct layers is noted as steam emulsification number.
The significance of steam emulsification number
- Good lubricating oil has low steam emulsification number; so that when it comes in contact with water it does not form an emulsion.
- The emulsion has a tendency to collect dirt, dust etc which reduces the lubricating property emulsification number arrears vegetable oils have high stream emulsification number whereas vegetable oils have high steam oils have high steam emulsification number.
- Oil having high steam emulsification number is preferred for preparation of lubrication emulsification like cutting fluids.