The difference between hot runner mold and cold runner injection mold

Material cost savings: The waste generated by the cold runner channel and gate is very large, especially the larger the volume of the workpiece due to the longer waste material. Some of these wastes can be reused, and some can not be reused. Even if they can be reused, the comprehensive performance of the materials is greatly reduced, and the equipment needs to be reused.

JK mold making

 Improve production efficiency: molding cycle of injection molded parts = injection time + holding time + cooling time + ejection time + trimming time. The longest of these is the cooling time. In plastic molds, the thicker the product wall, the longer the cooling time. Since the cold runner needs to feed multiple mold cavities or more at the same time, the wall thickness of the product in the cold runner is usually greater than the thickness of the injection molded article itself. Because of the cooling time difference between the cold runner melt and the injection molded article, the cold runner is eliminated and the cooling time will be shortened. The difference in injection time is also an aspect of replacing the cold runner with a hot runner. The difference in injection time is due to the extra time required to fill the cold runner. This is because the mold of the cold runner increases the opening/closing stroke of the injection molding machine, and the increase in stroke is to ensure the safe ejection of the cold runner. Products coated with hot runners are more suitable for automatic removal of products. Since there is no interference from the cold runner to the product removal, the secondary manual operation of the injection molding process, such as the separation of the product from the runner, the trimming of the product and the packaging time can be greatly shortened or completely eliminated. As a result, the production capacity per unit time is increased, that is, the production efficiency is improved.

PLASTIC injection mold making

 Improve the quality of the parts: the use of hot runners can effectively improve the surface quality and mechanical properties of the products, greatly improve the warpage of thin-walled parts, and ensure the quality of injection molded parts of multi-cavity molds.
    In particular, the needle-type nozzle has a more obvious effect on improving the appearance quality of the injection molded article, and its main advantage is that no in-situ residue is left on the product. The ability to use larger diameter gates allows for faster cavity filling and further reduces injection pressure and product distortion. It can prevent the phenomenon of drawing and flowing when opening the mold; when the screw of the injection molding machine retreats, it can prevent the material from being sucked back from the cavity.