抄録
In the conventional system of lubrication, lubricating oil is renewed with fresh oil after it is used for some period. Accordingly, waste oil is generated in the conventional system. The authors have developed a new system that makes it possible to use lubricating oil semi-permanently without oil renewal. In the new system, therefore, no waste oil is generated and it is enough to supply only a small amount of fresh oil sometimes to compensate for the lost oil. For a long time, this system has been working well in many marine and cogeneration diesel engines in practice. The new system always keeps the lubricating oil clean as the kidney of animals always keeps their blood clean. This is why lubricating oil can be used semi-permanently and the new system is called kidney system. The new technology can be used to clean and recycle many kinds of liquids. This paper reports that the kidney system was a great success in hydraulic systems of some construction machines of a company resulting in higher reliability. It also reports about some test results which show that the kidney system made waste oils and oils being used even cleaner than fresh oil in various types of hydraulic machines.
