Table Mould injection deformation, bending and twisting phenomenon is mainly due to shrinkage of the plastic flow direction is greater than vertical, the anisotropy shrinkage of each part is different, because the warpage of injection moulding is part of the residual internal stress is unavoidable due to large warpage, here It is the cause and solution for the warpage and deformation of plastic injection moulding.
1. Insufficient cooling or uneven
When not fully cooled, the top thrust of the mandrel tends to deform the component, so it deforms if the component is not sufficiently cooled. The solution is to adequately cool in the mould cavity and then fully harden before it can be pushed out. It also reduces table mould temperature and extends cooling time.
2. Caused by forming strain
The deformation caused by the forming strain is mainly caused by the difference in the shape shrinkage in the direction and the change in the wall thickness. Therefore, by increasing the table mould temperature, increasing the melting temperature, lowering the injection pressure, and improving the flow conditions of the casting system, the difference in direction shrinkage can be reduced.
3. Rod caused
Some parts are not properly demolded, and the ejector is used to force the demoulding to deform. Plastic parts that are not easily deformed will not deform at the same time, but cracks will occur. The elimination method is to improve the polishing of the table mould, making it easy to release, and sometimes using the release agent to improve the mould release property.
4. Correct product warpage
If it is necessary to correct the product removed from the table mould, the simple method is to calibrate the product and add weight to the correction tool, but the weight of the weight must be clearly determined. Or place the warped product on the straightener and place it in hot water close to the heat distortion temperature of the product and straighten it by hand. However, it should be noted that the temperature of the hot water should not be too high, otherwise the deformation of the product will be more harmful.
