First, we have to determine the parameters: the ratio of length to diameter, compression ratio, diameter, pitch, length, brand, number, materials used, and other commonly used parameters. According to the different types of each type, different materials will be selected according to different materials. The speed of melting, the heat absorption of melting, melt viscosity, water absorption and thermal stability are different, and the shape of plastic molding screw of injection molding machine is different. Even the same kind of plastic, because of the different products, plastics added flame retardant, lubricants, glass fiber, inorganic minerals and other modifiers and filler different, or the requirements of mixed color, melting homogenization of different requirements, the shape of the unfused particle material is different, the screw has different requirements to choose.
The screw press is selected according to the model series, because the injection molding machine has a very large variety of series, so we should choose which kind of injection molding machine, or which series to produce, such as the general thermoplastic or the wood raw material or PET raw material, which are monochrome, twin-screw, polychromatic and interlayer. Or mixed color, etc. In addition, some products need high stability (closed loop), high precision, ultra high shooting speed, high fire pressure or rapid production (multi loop), and a suitable series must be selected to make the corresponding special.
