In the injection molding of injection molds, cracks in plastic products are a very common problem. So, what can we do to eliminate the cracks in injection mold products?
XNUMX. Reasons for cracks in plastic products
1. Residual stress caused by the setting conditions of molding (oversaturated mold);
2. Residual stress occurred during demolding;
3. Stress concentration caused by the shape of the product;
4. The error caused by the thermal expansion of the same insert;
5. Deterioration of materials.
XNUMX. Related knowledge
1. Pre-heating of metal inserts can alleviate the residual stress during forming. The same principle is to use post-forming annealing instead of heating inserts;
2. In the molding setting conditions, the measure of lowering the injection pressure is the most effective;
3. If the ejector pins are balanced separately, apply a greater force when ejecting the mold.
Third, the solution to eliminate the cracks of injection mold products
1. Immediate: increase the temperature of the barrel, reduce the injection pressure, and reduce the demolding speed;
2. Short-term: improve the finish of the mold cavity;
3. Long-term: The demolding angle should be sufficient, the demolding pins should be distributed balancedly, the products should not be designed with sharp angles, and the thickness differences of the products should be avoided as much as possible.
Fourth, the difference in materials
1. Because materials such as polycarbonate (PC), PVC, etc. are easy to stick to the chrome-plated layer of the mold, especially in the corners, it becomes an inverted cone, so pay attention;
2. Polycarbonate (PC) is prone to cracks in the mold inserts. In this case, it is better to add reinforced glass fiber to the material.
Dongguan WONDER Precision Plastic Products Co., Ltd. has focused on injection molds for 10 years. The yield rate of injection molded products is 100%. It is specialized in injection mold manufacturing, injection mold opening, and injection mold injection., Spraying processing, silk screen spraying to assembly one-stop serviceInjection Mold Factory.
Dongguan WONDER Precision Plastic Products Co., Ltd. was established on November 2006, 11. It is located at the foot of the Daling Mountains in Dongguan with beautiful scenery and fresh air, close to the national highway, and convenient transportation; modern standardsThe industrial park covers an area of 15000 square meters. There are more than 500 employees in the factory, including 70 mold technicians and 35 quality control personnel. The annual output has reached several hundred million yuan.A complete industrial chain such as assembly.
Link to this article：Method to eliminate cracks in injection mold products