Plastic extruder nozzle preheating device

The utility model discloses a plastic extruder nozzle preheating device which comprises a nozzle material pipe and a preheating assembly arranged outside the nozzle material pipe in a sleeved mode, the preheating assembly and the nozzle material pipe are arranged in a rotating mode, and a first heating disc and a second heating disc are symmetrically arranged above and below the preheating assembly. The preheating assembly is rotationally arranged on the nozzle material pipe, during preheating, heat introduced into the first heating disc can enter the high-heat cavity of the sleeve and enters the warm-heat cavity after being absorbed by the nozzle material pipe, meanwhile, heat introduced into the second heating disc can directly enter the warm-heat cavity, heat in the warm-heat cavity is supplemented, and the heat utilization rate of the nozzle material pipe is improved. The heat in the warm cavity and the heat in the high-heat cavity are uniform, so that the nozzle material pipe is preheated; in the heating