The material is made to conduct a compound motion in the cone because of the rotation and revolution of the screws.The effected motions include: 1.The revolution of the screw along the wall making the material conduct a circumferential motion; 2.The rotation of the screw making the material rise along the screw from the cone bottom; 3.The compound motion of the rotation and revolution of the screws making partial,material can be absorbed into the screw cylindroid meanwhile,under the action of centrifugal force,the partial material in the screw cylindroid discharges radially. 4.The rised material drops under its sole weight.the four kinds of motions effect convection,shearing,diffusion in the cone ,thus quick and even mixing can be achieved.