• To understand how the blow moulding process works.• To be able to identify the processes used in the creation of different bottles.

• 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.

• Your presentation board is neat and looks interesting.

Molten plastic pours into the mould (this can come from an injection moulding machine). It forms a almost test tube like shape – called a parison.

The mould shuts to stop the flow of molten plastic or glass and keeps the parison warm. The blow pin (which blows air) then moves up into the parison.

Air is then blasted into the parison and it expands to fill the walls of the mould. It is then quickly cooled to keep the structure.

The blow pin moves back and allows the mould to open releasing the cooled shape.

Blow moulding is most commonly used to create bottles for soft drinks. It can be used in conjunction with an

injection moulding machine to supply the molten plastic.

Blow moulding can also be used in the manufacture of glass bottles.

The most commonly used plastics in this method are LDPE, HDPE and PET which are

both used to make liquid containers.

Advantages Disadvantages

Quick method of mass production.

Buying new moulds can be expensive.

Low running costs once set up.

Changing moulds for batch production is time consuming.

Will make identical products out of same mould.

Doesn’t need people to operate.