About mold for injection molding
njection molding is a popular manufacturing process because it’s one of the best ways to manufacture plastics. It is especially valuable in the consumer industry, where plastics are a leading component of many products.
Injection molding makes it possible to mass-produce small, detailed components quickly and at a consistently high level of quality. While the plastic components may look simple from the outside, the process to make them is complex and has many moving parts.
How does it Work?
The first stage of injection moulding is to create the mould itself. Most moulds are made from metal, usually aluminium or steel, and precision machined to match the features of the product they are to produce.
Once the mould has been created by the mould-maker, the material for the part is fed into a heated barrel and mixed using a helical shaped screw. Heating bands melt the material in the barrel and the molten metal or molten plastic material is then fed into the mould cavity where it cools and hardens, matching the shape of the mould. The cooling time can be reduced through the use of cooling lines that circulate water or oil from an external temperature controller. Mould tools are mounted on plate moulds (or ‘platens’), which open once the material has solidified so that ejector pins can eject the part from the mould.
Separate materials can be combined in one part in a type of injection moulding called a two-shot mould. This technique can be used to add a soft touch to plastic products, add colours to a part or produce items with different performance characteristics.
