Abstract:The lubricity,wear resistance and extreme pressure of additives such as new sulfuration polyester and chlorinated paraffin in deep hole drilling cutting oil were compared by using four ball extreme pressure and wear resistance tests and tapping torque tests.The feasibility of replacing chlorinated paraffin with new sulfuration polyester in deep hole drilling cutting oil was explored.The results show that compared with chlorinated paraffin,new sulfuration polyester has excellent performance,which can effectively improve the lubricity,wear resistance and extreme pressure of cutting oil,and significantly enhance the sintering load of cutting oil.The new sulfuration polyester can effectively replace chlorinated paraffin as a chlorine free extreme pressure additive for deep hole drilling cutting oil.