PET plastic injection molding process is one of the very important technology in the plastics processing, PET plastic bottles, most of the plastic packaging factory using blow molding production process, injection molding process is particularly unique processing advantages for PET for injection molding, technicians need to consider many factors, as follows.
PET plastic Description: chemical called polybutylene terephthalate PET ester, also known as polyester. Current customers are mostly used in GF-PET, mainly playing preform.
PET in the molten state the rheology of a better, larger effect than temperature of pressure on viscosity, therefore, mainly from the pressure to change the melt fluidity.
Chemical and physical properties of PET: PET around the glass transition temperature at 165 c, material temperature range is 120~220℃. PET strong Hygroscopicity at high temperature. For PET reinforced by glass fiber material, are also very prone to bending deformation at high temperature.
You can add crystals Enhancer to increase the degree of crystallization. Processing of transparent products with PET have the gloss and heat distortion temperature. Can add to the PET mica and other special additives reduce the deformation to a minimum. If you are using a lower die temperature, using non-transparent products are available to fill the PET material.
Injection molding: injection molding method is mainly used to enhance the shape of the PET. Screw Rod injection machine is usually used. Screws have to be hardened, so as not to occur after long-term use-wear. Injection nozzle hole length should be as short as possible, the diameter should be controlled at about 3mm.
Enhanced PET melting point as high as 260 ℃, to prevent nozzle clogging, larger power heaters should be installed. In addition, the tip of nozzle hole the best into the inverse Cone as shown in Figure-1, the flow of molten material can be easily cut and the nozzle.