• To understand how the injection moulding process works.• To be able to identify the processes used in the creation of plastic products.

• To apply your knowledge and successfully approach an exam style question based on blow moulding.

• To create an information sheet that you can use for revision guidance later.

• You could be asked about the various Industrial Processes used to manufacture products. One area that often pops up in the exam is blow moulding (get it..?). It’s important to understand not only the process but the application.

• You have explained the process step by step in an easy to read way (imagine you are explaining this to Year 7 students).

• You have given an overview about how it is currently used and what specific materials are used with it (e.g. PET plastic).

• You have weighed up the advantages and disadvantages of manufacturing with this method.

• You have the three subtitles; overview, applications and process.

• You have included some images of it’s current applications.

• Hopper, heater, motor, Archimedean screw, mould.

1. Granules of plastic powder are poured or fed into a hopper which stores it until it is needed.

2. A heater heats up the tube and when it reaches a high temperature a screw thread (called an Archimedean screw) starts turning.

3. A motor turns a thread which pushes the granules along the heater section which melts then into a liquid. The liquid is forced into a mould where it cools into the shape.

4. The mould then opens and the unit is removed.

Materials such as polystyrene, nylon, polypropylene and polythene can be used in a process called injection moulding. These are thermoplastics - this means when they are heated and then pressured in a mould they can be formed into different shapes.

Advantages Disadvantages

All products from same mould are identical.

Size can be limited.

The same mould can be re-used again and again.

Moulds can be expensive to make.

Moulds can quickly be changed for batch produced products.

Need to have long runs with the same mould to make it worth the expense of making it.

Plastic powder or granules are usually from recycled plastics.

Some plastic can be wasted in runs offs etc.

Product Mould

Archimedean Screw

Hopper

Motor

Plastic powder/granules

Heater

Melted granules