Four techniques to improve the precision of thin-wall injection molding

The application range of plastic parts is becoming more and more extensive, from simple tableware, kitchen utensils to complex mechanical parts, electronic product shells, etc., plastic parts are used. When manufacturing, we must pay attention to its precision requirements from the beginning of mold manufacturing.


What are the factors that determine the accuracy of the plastic injection molding process? How can we improve the precision of thin-walled injection molded parts?

1. Closing mold pressure: In principle, it should be greater than the total pressure of plastic injection into the mold, based on no burrs.

2. The pressure and speed have partly the same relationship in the mold. The purpose of the mold is to make the raw materials enter the mold evenly, thoroughly, and fill the corners in an appropriate amount. Too low will cause short shots, shrink, and too high will cause hairs and oversaturation. Undesirable phenomena such as sticking, scorching, fragile molds and high internal stress.

3. The speed of the material determines the condition of the raw material in the mold runner and the finished product. There will be burrs, oversaturation, and scorching. If it is slow, short shots, shrinkage, poor bonding and easy breakage will occur.

4. The temperature of the raw materials is different, the temperature is different, the color is not uniform when the melt is too low, and the internal stress of the finished product is increased. Because the temperature is too low and the pressure is too high, it may cause the screw to break, and the product may be too high. The burrs also have a temperature difference due to cooling, causing shrinkage. The raw materials will decompose, turn yellow, change color, and break easily. The cooling time becomes longer and the gas is not easy to be discharged.