The Distinction and Correct Application of Injection Molding Machine Screw
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 general-purpose type. These three types of screws have their own shapes and functions. Gradual screw is mainly used to process amorphous plastics with a wide softening temperature range and high viscosity; abrupt screw is mainly used for processing crystalline plastics with obvious viscosity and melting point; general purpose screw is mainly used for processing crystalline and amorphous plastics.
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 distinguished by four areas, which are solid conveying zone, melting delay zone, solid melting zone and 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 the molten plastic.
2. Distinguish according to geometric shape
According to the geometric shape, it can be divided into three sections: feed zone, compression zone and metering zone. The feeding area is to fix the depth of the screw groove, and 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, shear compression and pressurized exhaust of plastic raw materials; the metering zone is the fixed depth of the screw groove. In addition to the function of the screw in the compression zone, it will also provide more pressure to ensure the uniformity of the melt temperature and the stability of the molten plastic.
The importance of the screw of an injection molding machine can be seen. Therefore, mastering the function of different screws is the basis and key to controlling the production of an injection molding machine.