Plastic injection molding process involves the use of plastic, or polymer. The granular polymer is fed into a heated barrel. It is also further melted and mixed in the barrel by the rotation process of a screw type plunger, as heat is generated by the friction between polymer granules when the screw is rotating.The melted plastic is then forced into a mold cavity with the required final shape through a nozzle by the screw rotation action. The mold is relatively cold which may have cooling channels run through it. This causes the molten polymer solidifies almost as soon as the mold cavity is filled. The solidified part with the final required shape is then ejected out when the mold open again. It will be further cooled down by the ambient air.Material: Polymer There are many types of polymer used in injection molding, depends on what kind of properties is needed. Basically it can be classified into 2 categories: Thermoplastic and THERMOSTATBelow is a list of most common polymer used in plastic injection molding: 1. PC 2. PC-ABS 3. ABS 4. POM 5. HIPSMachine Plastic injection machine is used to hold the mold in place and to melt the plastic and china chair mould suppliers it into the mold cavity.Injection machine is classified by it tonnage. Tonnage is the clamping force that the machine use to clamp the mold during injection molding process. It can be ranged from less than 10ton to 5000 tons, depend on part size and material used.Another variety of injection machine is whether it is single injection machine or double injection machine. For double injection machine, it will have 2 set of screw plunger, hoppers and nozzles.