In the production process, the main factor that usually affects the dimensional accuracy of the Plastic Injection Mould
is the shrinkage of the injection molded part. The greater the shrinkage, the worse the accuracy. Therefore, due to the large shrinkage of PP and POM injection molded parts, the accuracy of their injection molded parts is usually poor. The shrinkage of other materials is usually not very small, so the dimensional accuracy of the injection molded parts is not very high under normal conventional injection molding conditions.
In fact, the shrinkage rate of the injection molded parts can be reduced by adjusting the machine, thereby achieving the purpose of improving the dimensional accuracy of the injection molded parts. We only need to greatly increase the time and pressure of the injection or holding pressure, so that the shrinkage of the injection molded parts can be reduced, the shrinkage rate can be significantly reduced, and the dimensional accuracy can be naturally improved.
Due to the limitation of the quality of the Injection Moulding Machine
, the pressure of the injection glue can not be adjusted too high, otherwise a large number of batches will be generated. Therefore, in the common ordinary injection molding machine, the main reason is to increase the time of injection molding or holding pressure to achieve the purpose of improving the dimensional accuracy of the injection molded parts.
In order to ensure the dimensional accuracy of the injection molded parts, the precision of the mold is the first condition to be guaranteed, and it is more important to select a stable and reliable injection molding machine with sufficient pressure.
Some high-precision injection molding machines developed in modern times are actually high-pressure injection molding machines with stable performance and high parameter precision. According to reports, the shrinkage rate of the injection molded parts can be almost zero, which means that the size of each injection molded part is almost the same as the size of the cavity, and the fluctuation range is only about one wire, and the precision is extremely high.