Abstract: In order to improve the coarse slime recovery effect in Gaozhuang coal mine coal preparation plant,using FX660-GT water-only sizing cyclone to replace the original FXJ-350 × 6 water-only sizing cyclone for sizing coarse slime.The paper introduces the structure,working principle,technical features,technical parameters of FX660-GT cyclone,and analyzed the application effect of the cyclone.The production practice shows that by adopting FX660-GT cyclone for separating of coarse slime,the thickening efficiency increased by 2.33%,the solid recovery rate of underflow increased by 3.32% and the clean coal recovery rate increased by 8%.