Plastic injection molding is one of the commonly used methods in plastic processing. The method is applicable to all thermoplastic materials and some thermosetting plastic materials, and the number of plastic injection molding products is much larger than that of other conventional metal plastic injection molding methods. Because the injection molding process not only produces more, but also applies to a variety of raw materials, can batch, continuous production, and has a stable size, easy to realize the automation and high speed of production, Plastic Injection Molding with a great economic benefits.
Plastic injection molding of the basic process is: plastic through the injection molding machine screw extrusion and heating, become molten state can flow melt. Driven by the screw, the plastic melt through the injection molding machine nozzle, mold main road, shunt and gate into the mold cavity, forming a certain shape and size of the products. The result of injection molding is to produce plastic products that meet the user's requirements. Plastic Injection Molding To obtain qualified products, must have a reasonable design, manufacturing sophisticated molds, but also need to have and the mold supporting the advanced plastic Injection molding equipment (injection molding machine) and reasonable processing technology. As a result, molds, injection molding machines and processes are often referred to as three essential elements for the smooth process of injection molding.
For the use of plastic injection molding processing methods for the production of plastic products, the reasonable molding process is the three basic elements of the most important factor. The so-called molding process, simply speaking, the pressure, temperature, time (speed) of the three elements constitute the most reasonable collocation. During the molding process, in particular, the formation of precision products, Plastic Injection Molding to establish a group of the best molding is not easy, because the factors affecting molding conditions are many, in addition to the shape of the product, mold structure, injection equipment, raw materials, etc., voltage fluctuations, environmental temperature changes on the molding has a certain impact.
Plastic Injection molding pressure plastic melt from the area of pressure to the low pressure of the region, in the plastic injection molding process, injection molding machine nozzle at the highest pressure to overcome the melt flow resistance in the whole process. Subsequently, Plastic Injection Molding the pressure along the flow length to the melt at the forefront of the gradual reduction, if the cavity internal exhaust good, then the melt front end pressure is atmospheric pressure.
Plastic injection molding pressure and the relationship between materials and different materials show different flow behavior, resulting in the required plastic injection molding pressure is also different. Plastic Injection Molding Melt viscosity is the most significant influence on injection pressure in flow properties. In general, melt viscosity is a function of temperature, shear rate, and plastic injection molding pressure. This means that the same plastic melts may have different viscosity depending on the molding process, and different materials may have a wider viscosity range. However, under the same temperature and shear rate, Plastic Injection Molding the viscosity of different materials is not the same, in the premise of satisfying the requirements of use, should be as far as possible to select the relatively small viscosity of the material.