Abstract: The trouble with the use of a 3-product H. M. cyclone is the entraiment of clean coal in middlings. To tackle this problem,the use of the pressure-fed 3-stage H. M. cyclone for rewashing of middlings is proposed based on the result of analysis and study. The paper presents a brief introduction to the structure and working principle of the cyclone. The law governing the distribution of both tangential and axial velocities is brought to light through simulation and analysis of the distribution of the flow field using ANSYS software. This well demonstrates theoretically the rationality of the structure of the cyclone.