Aiming at serious waste problem of traditional casting cooling,spray gun and air compressor were used to achieve micro lubrication,adjusting the spray gun knob could change the air intake and cooling liquid in size,so the lubrication cooling effect was improved and the amount of coolant was greatly reduced.Not only the production cost is reduced,but also it is conducive to protect environment.The micro lubrication system which is transformed by spray gun has the characteristics of simple structure,low cost and convenient use.It is suitable for various CNC machine tools and common machine tools.