Plastic Injection moulding process :-
The moulding material is loaded into the hopper from which it is transferred to a heating section by a feeding device, where the temperature is raised to 150°C to 370°C and pressure is built up. The material melts and is forced by a injection ram at high pressure through a nozzle and sprue into a closed mould which forms the parts.
The mould is in at least two sections, so that it may be split in order to eject the finished component. For the process to be competitive, the mould must be fairly cool and consequently the mould must be cooled by circulating water. Injection moulding machines have a high production capacity some can produce from 12 to 16 thousand parts per shift. This method is suitable for making parts with complex threads and intricate shapes, thin-walled parts etc., Typical parts include: Cups, containers, housings, tool, toys, knobs, communication components such as telephone receivers etc.,
- Injection moulding is used to create many things such as Cups, Containers, tools, Mechanical parts (Including gears).
- Injection moulding is the most common modern method of manufacturing parts. It is ideal for producing high volumes of the same object.
- Injection moulding allows for high production output rates.
- Often times parts do not need additional finishing process.
- You may also use fillers for added strength.
- More than one-material may be used at the same time when utilizing co-injection moulding.
- Full automation is possible with injection moulding.
- All scrap may be reground to be reused , therefore there is very little waste.
- The main disadvantage is cost of tooling and cost of operation.
- In order to be particle, large production runs are necessary.
- Initial tooling costs are higher than other methods.
- There are some design restrictions , so not all compounds are suitable for injection moulding.