When it comes to the hot runner in the plastic mold, al […]
When it comes to the hot runner in the plastic mold, although it is used less, everyone should not be unfamiliar, giving the impression that the mold price is high. Why is there such a hot runner system technology? What are the advantages of hot runner technology, what does it look like in the plastic mold manufacturing process? Under the general process, what problems exist?
A. Difficulties in filling
B. Deformation of thin-walled parts
C. Waste of runner material
D. The quality of the injection molded parts of the multi-cavity mold is not the same
The emergence of hot runner technology provides a more complete solution to these problems. In general, the use of hot runners has the following benefits:
1. The pressure loss in the flow channel is small, the plastic fluidity is good, and the temperature is uniform, the internal stress and deformation of the product will be reduced, and the surface quality and mechanical properties of the product will be greatly improved; (common shrinkage, insufficient filling, weld lines, Color unevenness, flashing, and warping can also be reduced);
2. Eliminate all or most of the flow path waste, the effective utilization rate of the material is high, and it is not necessary to recycle the old materials;
3. Shorten the molding cycle, mold opening stroke, and improve production efficiency;
4. The hot runners are all automatically cut off the gate, which can improve the degree of automation;
5. Reduce the injection pressure, which is beneficial to protect the mold and extend the service life;
6. Multi-cavity mold can ensure uniform filling and consistent quality;
Every technology has its own shortcomings, and hot runner technology is no exception. In addition to the high cost of molds, the mold structure is also more complicated. It requires strict temperature control and requires professional maintenance. Generally, small-volume production molds use hot runners with low cost performance, which is not recommended. If the product volume is large, the unit price is acceptable. The use of hot runners can not only improve the injection quality of the products, but also save the nozzles and prolong the service life of the molds.