The screw is an important part of the injection molding […]
The screw is an important part of the injection molding machine. Its role is to transport, compact, melt, agitate and apply pressure to plastics. The barrel is the same as the extruder and is an important part of the extruder. The outer surface of the screw is cut with a spiral grooved cylinder or a cone having a tapered spiral groove. The screw has different heads, hexagonal screws, and others, such as large flat screws, hexagonal screws, etc.... It is made of metal and has high temperature resistance and high resistance. Compared with the grinding property, the structure of the barrel is relatively simple. In a large extruder, the structure of the barrel can be composed of several segments.
In the structural form application is more divided into: integral, segmented, bushing, casting, bimetal layered barrel. All of this is done by the rotation of the screw in the barrel. When the screw rotates, the plastic will rub against each other on the inner wall of the barrel, the bottom surface of the screw groove, the screw advance surface, and between the plastic and the plastic.
The forward advancement of the plastic is the result of this combination of motion, and the heat generated by the friction is also absorbed to increase the temperature of the plastic and melt the plastic. The design of the screw will directly affect the extent of these effects.