Most of the extruder processing materials are mainly PE, PVC, TPU, etc. The thermal history of these materials is not long, and black spots will occur if they stay in the screw for a long time. Some large extruders have barrels connected to the die. The flow channel in the middle is relatively long, and some also have storage tanks. There are more corners and dead ends, which are easy to hide glue and are more likely to produce black spots than ordinary extruders. It is well known that black spots will be generated when the machine stops. How to clean up the black spots in the screw after stopping?
The screw can completely remove the impurities on the screw, but the time required for the screw is very small, and the impurities in the barrel and die are not effectively treated. In addition, the frequent setting of the screw is also challenging the precision of the machine. For the sake of the machine, it is better to dial the screw less.
In response to the black spot problem in the market, there are special extruder black spot cleaning materials that can effectively clean the original black spots in the machine. After the black spots are resolved, we recommend finding the source of the black spots, focusing on prevention, which will require much less time and materials, while ensuring normal production. For example, most of the black spots are caused when the machine is shut down. We recommend using shut-down maintenance materials. Adding the screw to the screw can prevent the residual materials from decomposing and carbonizing, thus preventing the occurrence of black spots.