The screw is an important component of the injection molding machine. In the production, the screw is responsible for conveying, compacting, melting, stirring and applying pressure to the plastic. The screw required by the injection molding machine can be divided into three types: gradient type, mutation type, and universal type. These three types of screws have their own shapes and functions. The gradual screw is mainly used to process non-crystalline plastics with a wide softening temperature range and high viscosity; the abrupt screw is mainly used to process crystalline plastics with obvious viscosity barrel nuts and screw and melting point; the general-purpose screw is mainly used to process crystalline and non-crystalline plastics. Crystalline plastic.

The screw is the core component of the production of the injection molding machine. It can distinguish different functions and functions according to the needs.

1. Distinguish by function

According to the function, the plasticizing screw can be divided into four areas, namely the solid conveying zone, the melting delay zone, the solid melting zone and the sol conveying zone. The screw operation of these four areas is independent of each other but there is also a connection. The screw in the solid conveying zone is connected with the feeding funnel to convey the plastic with increasing temperature forward. The screw in the melting delay zone causes the sol to accumulate in the screw groove to form a melting pool; the role of the screw in the solid melting zone can be divided into two parts, one is to assist the melt to plasticize, and the other is to transport the melt to the melting pool. The screw in the final sol conveying zone will keep the melt temperature uniform and stabilize the flow of molten plastic.

2. Distinguish according to geometric shape

According to the geometric shape, it can be divided into three sections: the feed zone, the compression zone and the metering zone. The feeding zone is used to fix the groove depth of the screw groove, which is used to push the plastic solid to melt before the end of the feeding; the screw in the compression zone is the groove depth of the tapered screw groove, which can assist the melting, mixing, and mixing of plastic raw materials. Shear compression and pressurized exhaust; the metering zone is a fixed groove depth of the screw groove. In addition to the function of the screw in the compression zone, it will provide more pressure to ensure the uniformity of the melt temperature and the stability of the molten plastic.