'We have 5 guest/s online'
11.2.1 Define sprue, flash, parison, die, draft angle and injection moulding.
11.2.2 Explain how an injection-moulded product is made.
Diagrams must include the hopper, hydraulics, heaters, screw, sprue and mould.
11.2.3 Outline the advantages of injection moulding.
Consider initial capital investment, tooling, accuracy, quality control and quantity of product.
NB can be considered a clean technology
11.2.4 Discuss how standardised bottle caps have constrained bottle design, but have cut costs for manufacturers.
Bottle caps can be classed as standardised parts. Bottle tops are injection moulded, while bottles are normally made by blow moulding. It is financially beneficial for a blow moulding company to use off-the-shelf bottle tops instead of purchasing an injection moulding machine and new tooling.
11.2.5 Describe how a blow-moulded product is made.
Diagrams must include the extruder, parison, the mould and air inlet.
11.2.6 Explain how a rotational-moulded product is made.
Diagrams must include the mould, filling the mould, heater chamber, rotation and cooling chamber.
11.2.7 Explain how a compression-moulded product is made.
Diagrams must include the mould, pre-form, hydraulic press, finished part and flash material.
11.2.8 Discuss why some products have to be made using compression moulding.
Consider the heat the product must withstand, quantity and type of product to be made. Refer to thermosets.
11.2.9 Describe how a vacuum-formed product is made.
Diagrams must include the vacuum chamber, former, platen, heater, air in and out.
11.2.10 Identify manufacturing methods suitable for thermoplastics and thermosets.
Thermoplastics: vacuum forming, blow moulding, injection moulding and rotational moulding. Thermosetting plastic: compression moulding.
Bulleted list and italicised paragraphs are excerpted from Design Technology: guide. Cardiff Wales, UK: International Baccalaureate Organization, 2007.
Images are clickable links to its location.