During the extrusion production process, there may be a […]
During the extrusion production process, there may be a phenomenon that the extruder screw / suddenly freezes. At this time, if the extruder protection device does not work, the operator should stop immediately. In most cases, the screw can still rotate, but the speed is slowed down, and at the same time the harsh metal scraping sound appears, the current rises sharply, and the operator should stop immediately.
The reason for this situation is:
1: Foreign matter enters the barrel and jams the screw. If it is a ferrous metal foreign body, it will cause great damage to the screw and the barrel
2: Deformation of screw and / or barrel
3: The barrel temperature is too low, or the filter plate is blocked, causing the barrel pressure to rise sharply, causing the screw to deform
4: The screw / barrel design is unreasonable. It is easy to happen that the screw design compression ratio is too large, and the screw / deformation occurs during use.
5: The thermal expansion coefficient of the barrel and the screw / material used is too different. When the barrel is heated, the barrel feeding seat is cooled, and the screw / if it is not cooled, it may be locked.