What are the methods for maintaining mold temperature during injection molding

Update:12-09-2019
Summary:

Mold temperature is a very important parameter in injec […]

Mold temperature is a very important parameter in injection molding. When injecting any kind of plastic, the surface of the mold should be substantially wet. Hot mold surface makes plastic surface

The liquid remains for a long time, creating pressure in the cavity. When the frozen skin is filled before the cavity is solidified and the cavity pressure presses the soft plastic against the metal, the surface of the cavity

The copy is very high.

On the other hand, if the plastic is placed in a cavity at a low pressure, even if the time is short, it may be contaminated by slight contact with the metal, sometimes referred to as a gate stain.

There is a limit to the surface temperature of the mold for each plastic and plastic part, which may result in one or more side effects (eg, components may be overloaded). Mold temperature

The higher the degree, the lower the flow resistance.

Since the injection flow control valves used in many injection molding machines cannot correct these changes, they naturally mean faster flow through the gates and cavities, and with electricity

As the charge increases, the efficiency of the runners and joints increases. pressure.

It can cause flash burrs. Before the high pressure is established, the high temperature model will not freeze the plastic entering the edge of the flash, so that the melt protrudes above the ejector and enters the sub

The gap in the offline. This requires good injection rate control and suggests that some modern flow control programmers can do this.

Generally, as the temperature of the mold increases, the amount of plastic condensation in the cavity decreases, making it easier for the molten material to flow in the cavity, thereby increasing component weight and improving

The surface quality. As the mold temperature increases, the tensile strength of the part increases.

Mold insulation method

Many molds, especially engineering thermoplastics, operate at relatively high temperatures, such as 80 degrees Celsius (176 degrees Fahrenheit). If the mold is not insulated, then

The heat lost from the air and the injection molding machine can be as easily lost as the injection cylinder.

Therefore, the mold frame is insulated and, if possible, the surface of the mold is insulated. If considering the hot runner mold, try to reduce the hot runner part and

Heat exchange between cooled injection molded parts. This method can reduce energy loss and warm-up time.

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