Oil re-circulation involves a continuous oil flow to the lubrication points. This oil is controlled both in quantity and temperature, it is collected by drains piping and returned to a supply tank. The oil is therefore "re-circulated" back to the point.
When the oil flows through the lubrication point it does not only act as a lubrication agent but also removes a large amount of heat from the bearing or lubrication area. The oil is the transported away and back to the lubrication tank. Oil re-circulation is used extensively in the power industry and pulp and paper industry allowing for increases in operating speed and performance thanks to the fast change-over of lubricant that removes heat and provides full-oil immersion lubrication.