1. Check out the debris in the plastic guess. Generally […]
1. Check out the debris in the plastic guess. Generally speaking, there is no debris in the fresh plastic purchased originally, but through transportation, weighing, drying, color mixing, especially the addition of recycled materials, it may be mixed with debris. It is as small as metal scraps, as large as heating coil nuts, paper clips, and even a bunch of warehouse keys, mixed into the barrel, it is self-evident that the damage to the screw is self-evident (the barrel will also be damaged as well. ), so it is necessary to install a magnet rack to strictly manage and monitor the feeding.
2. Moisture contained in the plastic has a certain influence on the wear of the screw surface. If the plastic is not completely swept away from the water before injection, when the residual water enters the screw compression section, it will form "steam particles" with high temperature and pressure that are melted and mixed in the molten plastic. Follow the injection material process to push from the screw. From the chemical section to the screw head, these "steam particles" relieve pressure and expand during the injection process, just like tiny impurity hard particles, which have a frictional damage effect on the wall. In addition, for certain types of plastics, under high temperature and high pressure, moisture may become a catalyst that promotes the cracking of plastics and produce harmful impurities that can corrode the surface of the metal. Therefore, the drying operation before plastic injection molding not only directly affects the quality of the parts, but also affects the operating life of the screw.
