Emulsification: Emulsification can be defined as the property of oils to get intimately mixed with water easily. Emulsions can be oil in water emulsion or water in oil emulsion. Certain oil from emulsions with water very readily. These emulsions tend to collect impurities and may cause abrasion and wearing out of the part that is lubricated. Thus, good lubricating oil should from such a emulsion with water breaks easily. This property is called emulsification.

Significance:

1.      In steam turbines, oils are contaminated with steam and hence quicker the oil separates out from the emulsion formed, better is the lubricating oil. Otherwise oil is along with the steam may be carried away and can clog oil lines and pumps.

2.      In cutting oils the higher the emulsification number, better the oil is. This is because the emulsion acts as a coolant as well as lubricant.