Molten plastic is injected into the injection mold under high pressure. The mold is manufactured by the injection mold manufacturer, usually made of steel or aluminum metal, and precision machined to form the shape of the desired parts. Injection molding is widely used to manufacture various parts, from small parts to the whole automobile body panel. It consists of filling time, pressure holding time, cooling time and demoulding time.
The cooling time of injection molding in Dalian accounts for a significant proportion, about 70% ~ 80%. Therefore, the cooling time will directly affect the molding cycle and output of plastic products. In the demoulding stage, the temperature of plastic products shall be cooled to be lower than the thermal deformation temperature of plastic products, so as to prevent the relaxation of plastic products caused by residual stress or warpage and deformation caused by external demoulding force.
Injection molding is often divided into two stages: in the first stage, most of the plastic is filled into the mold, generally 90% ~ 99.9% of the volume of the whole product; In the second stage, the product is compacted to obtain the product with the same mold structure and shape. In the second stage, although only relatively few plastic melts are filled into the cavity, it is very important for the surface finish, aesthetic appearance and product size of the product.
In most cases, the second stage of injection molding uses two parameters: pressure and time. The reaction speed of the hydraulic system should be fast, and the clamping system should have enough rigidity. The proportion of plastic materials in life is higher and higher, and the requirements for their quality are higher and higher. As an important production means, injection molding is more and more urgent to improve technology. There are many influencing factors of injection molding products, but the processing conditions of injection molding are one of the important influencing factors.