The three-in-one vacuum drying machine is primarily composed of components such as the drive system, motor reducer, frame, bearings, conical cylinder (with jacket), agitator screw, sampling valve, packing seal, etc. The equipment is designed with the motor reducer directly connected to the agitator screw, featuring variable frequency speed control from 0 to 20 rpm. The screw and agitator shaft are welded in a specific mold, ensuring uniform spacing between the screw and drum wall for stable operation; a flexible graphite packing seal is used between the agitator shaft and the head, effectively preventing the entry of external impurities. Both the conical cylinder and the elliptical head are equipped with jackets, allowing the introduction of different types of heat mediums and withstanding certain pressure. While agitating and mixing, heating is also applied to achieve the drying of materials, resulting in good drying effects and stable operation.