Hydraulic screw plasticizing device

The utility model relates to the field of injection molding machine, in particular to a hydraulic screw plasticizing device. The hydraulic screw plasticizing device comprises a pre-plastic front charging barrel, a pre-plastic charging barrel, a screw, a charging seat and a hydraulic motor for driving the screw to rotate; the plasticizing device also comprises a screw self-locking drive mechanism; the screw self-locking drive mechanism comprises a thrust seat, an apical shaft and a self-locking piston; two ends of an inner hold of the self-locking piston are provided with bearings and are sleeved on the apical shaft; the outer circumference of the self-locking piston is provided with a sealing groove; and a double-function oil cylinder is formed between the thrust seat and the sealing groove. By the hydraulic screw plasticizing device, the function of hydraulic self-sealing is achieved by the screw, and backflow of molten materials can be effectively prevented.