Hopper dryer is a type of auxiliary machine for injection molding machines, belonging to injection molding machine accessories. It is a very effective and economical equipment for drying plastic raw materials (plastic particles, plastic masterbatch) of injection molding machines. It can dry wet plastic raw materials during packaging, transportation or recycling, and avoid defective products in the production process of injection molding machines. The hopper dryer can be directly installed on the injection molding machine to dry plastic raw materials, which not only has high drying efficiency but also saves space