How to prevent the depression of the injection molded product When the material is more shrunk than the material of the adjacent wall in the thicker part of the rib, the dent in the injection molded part will develop. The presence of this feature produces thicker areas that cool down more slowly than adjacent areas. Different cooling rates result in pits on adjacent surfaces, known as dents. This defect represents a great limitation on the design and molding of plastic products, especially in thin-wall applications such as TV screens and displays. Although toys often have dents visible on the surface, consumer electronics components must be truly dent-free. The formation of dents can be attributed to one or more factors including the processing method used, part shape, material selection, and mold style. The part shape and material selection is usually determined by the OEM manufacturer and may not be easily changed. However, several aspects of the mold design available to the molder may affect the recess. Cooling runner design, gate type, and gate size can have a variety of effects. For example, small gates like tunnel gates are much faster than edge gates. Too early gate cooling will shorten the pressure holding time in the cavity and may increase the possibility of dents. For molding companies, controlling process conditions is the solution to the problem of sinking. Holding pressure and time severely affect the sag. When the parts are filled, excess material is filled into the mold cavity to mitigate the effects of material shrinkage. Shorter compression stages will increase shrinkage and produce more or larger dents. Although molding companies can adjust dwell conditions to improve dents, this approach may not reduce dents to an acceptable level. Other methods include fine-tuning of parts including part replacement, or gas-assisted, foaming, and other process trimming.
Face Powder,Makeup Palette 3 Shades Highlighter Powder,Waterproof Light Face Contour Highlight Palette
Guangzhou Shishi Daily Chemical Co.,Ltd. , https://www.cosmeticok.com