what are the common problem in the plastic mould injection process

     During the processing of plastic molds , there will always be some small problems that cause us headaches. These problems are not big and small and cannot be ignored. However, if there are problems, we must find them in time and deal with them. Therefore, in the manufacturing process of plastic molds, we must pay attention to small details.

             Bubbles are a common problem, which refers to the phenomenon that air is trapped in the cavity and the product produces bubbles. This is mainly because the gas trapped in the cavity cannot be exhausted in time, which may cause surface blistering and air trapping inside the product.

              Dissatisfaction with plastic. Black spots refer to the presence of black spots on the surface of the part. This causes this phenomenon to be caused by the thermal decomposition of plastic or the presence of dirty recycling, foreign objects, other colored materials, or low-molecular materials that are easily degraded. The brittle part of the part means that the part easily cracks or breaks in some parts. Brittleness is mainly due to the breakage of macromolecules due to material degradation, which reduces the molecular weight of macromolecules, thereby reducing the overall physical properties of the polymer.

              The reason is that the drying conditions are not suitable, the injection temperature is not set properly, and the gate and runner system are not set properly. Scorch marks refer to the fact that the gas in the cavity cannot be removed in time, resulting in the phenomenon of burning at the end of the flow. Layered peeling is the peeling of the surface of the product one by one. This symptom is caused by mixing with other incompatible high-molecular polymers, using too much release agent during molding, too low melt temperature in the cavity, or too much water. Flow marks are wavy surface defects near the gate. This condition is caused by the melt temperature being too low, the mold temperature being too low, or the runner and gate sizes being too small.



             Underfill is a phenomenon in which the mold cavity cannot be completely filled. This is any factor that prevents polymer melt flow or under-molds the polymer, which can lead to under-injection. Material flower refers to a surface defect in which moisture, air, or carbides show an emission distribution on the surface of the workpiece along the flow direction. It is due to the high moisture content in the raw materials, air and polymer degradation in the raw materials.

             Shrinkage is a more serious problem. It is a phenomenon that the product has a concave surface at the wall thickness. It usually appears at the strengthened shin, countersink or internal grid. It is because the injection pressure or the holding pressure is too low, or the holding time or the cooling time is too short.

            During the processing of plastic molds , various mold problems will occur. When we encounter problems, we must see the problems clearly and deal with them in time so that the mold can run normally and without errors to ensure the normal processing of the product.