Plastic injection molding is a method of forming a thermoplastic or thermosetting molding material in a mold cavity by uniformly plasticizing it in a heating cylinder and then by a plunger or a moving screw to a closed mold. Injection molding is suitable for almost all thermoplastics. In recent years, Plastic Injection Molding injection molding has also been successfully used to shape certain thermosetting plastics. Injection molding of the molding cycle is short (a few seconds to a few minutes), the quality of molded products from a few grams to dozens of kilograms, can shape a complex shape, accurate size, with metal or non-metallic insert molding. Therefore, the method of adaptability, high production efficiency. Injection molding machine is divided into plunger injection molding machine and screw injection machine two categories, Plastic Injection Molding by the injection system, clamping system and mold three parts;
Plastic Injection Molding Features:
Reduce the residual stress, reduce the warpage;
Eliminate the traces of depression;
Reduce the clamping force;
Reduce the length of the runner;
Shorten production cycle time;
Extend mold life;
Reduce the mechanical loss of injection molding machine;
Used in the thickness of the finished product.
Plastic molding, the use of this process of processing polymer is (according to the size of the order); phenolic plastic, polyester plastic molding, melamine, epoxy resin, urea-formaldehyde plastic, Plastic Injection Molding vinyl ester polymer and phthalic acid di Allyl ester (DAP).
Most thermosetting plastics contain a large amount of filler (up to 70% by weight) to reduce costs or increase their low shrinkage properties, increase strength or special properties. Common fillers include glass fibers, mineral fibers, clay, wood fibers and carbon black. These fillers may be very abrasive and produce high viscosity, Plastic Injection Molding which must be overcome for processing equipment.
The injection molding process uses a screw to flow the material through the heated barrel, which is circulated in water or oil around the jacket in the barrel. The screws can be designed in different types of each material, compressed slightly to remove air and heat the material to obtain low viscosity. The flow of most thermosetting materials here is quite good.
Plastic injection molding working principle
Similar to the syringe used in the injection, it is the use of screw (or plunger) thrust, will have been plasticized molten state (ie viscous) plastic injection into the closed cavity, Plastic Injection Molding the solidification of the finished product The process.
Plastic injection molding is a cycle of the process, each cycle mainly include: quantitative feeding - melt plasticization - pressure injection - charge cooling - Kai mold pickup. Remove the plastic parts and then closed the mold, the next cycle.