How do you make the insulation method of the injection mold?

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Mold temperature is the most important variable in injection molding - no matter which plastic is molded, it must be guaranteed to form a basic wetting of the mold surface. A hot mold surface keeps the plastic surface liquid for a long time, enough to create pressure in the cavity. If the cavity is filled and the cavity pressure presses the soft plastic against the metal before the frozen skin hardens, the replication of the cavity surface is high.
On the other hand, if the plastic entering the cavity at low pressure is suspended, no matter how short the time is, its slight contact with the metal will cause stains, sometimes referred to as gate stains.
For each plastic and plastic part, there is a limit to the surface temperature of the mold beyond which one or more adverse effects may occur (for example, the component may overflow the burrs). Higher mold temperatures mean less flow resistance.
On many injection molding machines, this naturally means faster flow through the gate and cavity because the injection flow control valve used does not correct this change, and filling will cause higher efficiency in the runner and cavity faster. pressure.
May cause flash burrs. Since the hotter model does not freeze the plastic that enters the edge of the flash before the high pressure is formed, the melt can flash over the ejector rod and spill into the gap of the dividing line. This suggests that good injection rate control is required, and some modern flow control programmers can do this.
Generally, an increase in mold temperature reduces the amount of condensation that the plastic has in the cavity, making it easier for the molten material to flow within the cavity, resulting in greater part weight and better surface quality. At the same time, the increase in mold temperature also increases the tensile strength of the part.
Mold insulation method
Many molds, especially engineering thermoplastics, operate at higher temperatures, such as 80 degrees Celsius or 176 degrees Fahrenheit. If the mold is not insulated, the heat lost to the air and the injection molding machine can easily be lost as much as the shot cylinder.
Therefore, the mold-frame is insulated and, if possible, the surface of the mold is insulated. If a hot runner mold is considered, an attempt is made to reduce the heat exchange between the hot runner portion and the cooled injection molded part, thus reducing energy loss and warm-up time.


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