An Overview of the Operating Process of a Plastic Granulator
Time：
2018-06-11
After entering the screw from the hopper, the plastic is conveyed forward by the rotating screw, driven by friction between the material and both the inner wall of the barrel and the screw surface. In the feeding section of the screw, loose solid pellets (or powder) fill the screw channels, and as the material continues to be fed, it begins to compact. Once the material reaches the compression section, the gradually decreasing screw flight depth combined with resistance at the die head causes the plastic to build up high pressure and undergo further compaction. Meanwhile, external heating of the barrel, together with intense stirring, mixing, and shear‑frictional heating generated by the interaction between the screw and the inner barrel surface, raises the plastic’s temperature as it comes into contact with the barrel.
After entering the screw from the hopper, the plastic is conveyed forward by the rotating screw, driven by friction between the material and both the cylinder wall and the screw surface. In the feeding section of the screw, loose solid pellets or powder fill the screw channels; as material continues to be fed, it begins to compact. Once the material reaches the compression section, the gradually decreasing screw flight depth combined with head resistance builds up high pressure, further compressing the plastic. Meanwhile, external heating of the barrel, together with intense stirring, mixing, and shear‑induced internal friction generated by the interaction between the screw and the inner cylinder wall, raises the plastic’s temperature. At a specific point in contact with the barrel, the temperature reaches the melting point, initiating melt flow. As conveying proceeds and heating persists, the amount of molten material increases while the unmelting portion decreases. By the end of the compression zone, most of the material has transitioned into a viscous flow state; however, temperatures at different points remain uneven. After passing through the homogenization section, temperature distribution becomes more uniform, and the screw extrudes the molten material into the die at a controlled rate, pressure, and temperature. The die, serving as the shaping component, imparts the desired cross‑sectional geometry and dimensions to the material. Following cooling and additional processing steps, the final molded product is obtained.
Related news
Shuangda
Hebei Shuangda Rubber Machinery Co., Ltd.
Tel：400-0319-386
Landline：+86-319-6017632
Email：shuangdaxiangsu@126.com
Official website：www.shuangdajx.com
Addr：Liyuantun Industrial Zone, Weixian County, Xingtai City, Hebei Province
Copyright © 2022 Hebei Shuangda Rubber Machinery Co., Ltd.