2018-06-04 10:50:00 0
How to avoid shrinkage marks in injection mold processing? In thicker parts of two-color injection mold parts, such as ribs or protrusions, the shrinkage is more serious than the adjacent position, because the cooling rate of the thicker area is better than the surrounding area. The area is much slower. The difference in cooling rate causes a depression at the joint surface, which is a shrinkage mark. So how to solve this problem? Cosme two-color mold to tell you:
How to avoid shrinkage marks in injection mold processing?
1. Mold design factors
The geometry and material selection are usually determined by the raw material supplier and are not easily changed. However, there are still many factors related to mold design in the mold manufacturer that may affect the plastic processing shrinkage.
2, cooling runner design
Cooling runner design gate type, gate size can have a variety of effects. For example, small gates such as tubular gates cool much faster than tapered gates. Premature cooling at the gate reduces the fill time in the cavity, which increases the chance of shrink marks.
3, adjust the processing conditions
For molding workers, adjusting the processing conditions is one way to solve the shrinkage problem of plastic processing. Filling pressure and time significantly affect shrinkage. After the part is filled, the excess material continues to fill the cavity to compensate for the shrinkage of the material. Too short a filling phase will result in increased shrinkage and eventually more or larger shrinkage marks.
This method of solving the plastic processing shrinkage itself may not reduce the shrinkage marks to a satisfactory level, but the molder can adjust the filling conditions to improve the shrinkage marks.
4, modify the mold
In the two-color mold injection molding process, the mold can be modified appropriately. A simple solution is to modify the conventional core hole, but this method cannot be expected to be applicable to all resins. In addition, the gas-assisted method can also solve the problem of plastic processing shrinkage.
How to avoid the shrinkage marks in the injection mold processing? These are the ways to avoid the shrinkage marks in the injection mold processing. If you need it, please call the Cosme two-color mold consultation.
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