In the universal screw, it is generally divided into three sections: the feed section, the compression section, and the homogenization section, and a complete set of barrels to match. First of all, we need to determine the parameters: length-to-diameter ratio, compression ratio, diameter, pitch, length, commonly used parameters such as the model of the model used, the number of cymbals, and the materials used. According to the difference of each model, each material used will be different. Different materials are selected according to the materials, such as the speed of melting, the heat performance absorbed during melting, melt viscosity, water absorption, and thermal stability. Each has its own differences, and the shape requirements of the plasticizing screw of the injection molding machine are very different. Even for the same plastic, because of different products, the flame retardants, lubricants, glass fibers, inorganic minerals and other modifiers and fillers added to the plastic are different, or the requirements for color mixing and melt homogenization are different. Different shapes of granular materials have different requirements on the screw to choose.
The screw is selected according to the model series. Because there are very many types of injection molding machines, we must choose at the beginning. We must first correctly determine which injection molding machine or series of this product should be produced, such as general thermoplastics. Plastic or bakelite raw materials or PET raw materials are single-color, twin-screw, multi-color, sandwich or mixed color. In addition, some products require conditions such as high stability (closed loop), high precision, super high rate of fire, high injection pressure, or rapid production (multi-loop), and must also choose the appropriate series to manufacture the corresponding dedicated.
