METHOD FOR BRINGING THE CONTENT OF AIR IN OIL INTO A STATE OF EQUILIBRIUM IN SYSTEMS OF CIRCULATION LUBRICATION AND IN HYDRAULIC SYSTEMS OF ROLLS

摘要

The invention concerns a method for bringing the content of air in oil into a state of equilibrium in systems of circulation lubrication and in hydraulic systems of rolls. When oil is loaded, air that has dissolved into the oil is liberated as bubbles, and extra air is mixed with the oil out the free air space in connection with the oil as bubbles so that the total content of air in the oil is increased and the amount of dissolved air is reduced. The return oil with a content of air higher than the state of equilibrium is passed back into the tank. In the method, an oil tank (10) is employed, into which the return oil is pumped from the top portion of the tank and from which the oil is passed to circulation from the lower portion of the tank. In the tank (10) the ratio of the height of the oil column to the volume of the tank is such that the time of dwell of the oil in the tank (10) permits that at least air bubbles of an order of magnitude of 1.5 mm and larger rise to the oil surface so that the oil that is pumped back to circulation can be made substantially free from bubbles.