Polymers manufacture Flashcards
Advantages of Injection Moulding
Very complex 3D shapes can be produced
High volume can be produced with consistent quality
Disadvantages of Injection Moulding
Initial set-up costs are high
Moulds are expensive
Identifying Injection Moulded Products
Complex 3-D shapes
Integrated fixings
Webbing
Ejector pin marks
Injection nipple
Identifying Extruded Products
Constant sectional profile
Long pieces
No seam marks
Advantages of Extrusion
Very long products can be made
Constant sectional profile
Relatively complex shapes are possible
Disadvantages of Extrusion
Limited cross sectional size
High set up cost
Advantages of Rotational Moulding
Very large products can be made
One piece hollow products
Disadvantages of Rotational Moulding
Slow process
Relatively simple shapes only
Identifying Rotational Moulded Products
One piece hollow object
Large objects
Relatively simple shapes
Thick walls possible
Advantages of Blow Moulding
Low energy = low cost
Fast process
One piece hollow products possible
Disadvantages of Blow Moulding
Limited use (hollow objects only)
Identifying Blow Moulded Products
One piece hollow object with one opening
Rounded edges
Clear seam on base
Complex details
Advantages of Vacuum Forming
Low energy consumption
Low initial setup costs
Moulds are quick and cheap to produce
Disadvantages of Vacuum Forming
Simple shapes only
Relatively slow process
Large draft angles required
Identifying Vacuum Formed Products
Simple shapes
Large draft angle
Irregular wall thickness
Calendaring Advantages
Very thin film produced
Fast process
Very large pieces possible
Calendering Disadvantages
Only suitable for making film
Relatively high setup cost
Identifying calendered products
Thin film
Compression Moulding Advantages
Complex shapes possible
Large products possible
Thick wall sections possible
Compression Moulding Disadvantages
Relatively slow process
High energy consumption
No undercuts possible
Identifying compression moulded products
Thick walls
Small draft angle
Relatively complex
Seam lines
what is put in funnel in injection molding
plastic granules
what goes in the hopper for extrusion
thermoplastic granules
what is put in the mold for rotation molding
thermoplastic polymer
