This equipment is used to purify the used machinery oil, hydraulic oil, compressor oil, motor oil, mediate-load gear oil, cooler oil, steel rolling oil, quench oil, flash swift quench oil, etc. in mine, metallurgical industry, machinery, chemical industry, rubber industry, instrument, traffic, petroleum drilling and exploring, construction ceramics, precision pressure casting, etc. The oil to be treated is from No.5 to No.1500 that is in high, mediate or low viscosity in movement. This kind of machine is specially used to purify the oil from cement, chemical and fertilizer production. Sometimes the oil to be treated has as much as 70% impurities in it, such as aqueous acid, ammonia acid, carbon, dust-sand-clay, moisture content, etc. The water separated form the oil treated by this equipment has different colors: the water color can be milk white if the aqueous acid in it is serious. The color can be blue if the ammonia acid in it is very much. The color can be white if the oil has been seriously polluted by alkalis. The waste water from the treated oil has much snow-like floating matter on it. This equipment takes only the physical principle methods to treat the oil. It takes no chemical agent for purification. Therefore, the oil treated remains its original color.