What the meanig of «Deemulsification»?
Small amounts of water that can enter the hydraulic system due to condensation of air can form highly viscous water-in-oil emulsions that are harmful to valves and pumps. Since the operating temperature in most industrial hydraulic systems is too low for this water to evaporate, it is essential that the oil has good water separability (demulsibility). The standard method for evaluating the demulsifying ability of an oil is ASTM D 1401. The method involves mixing equal amounts of oil and water for 5 minutes at 55 °C, after which the time required to separate the emulsion is determined.