Lecture 2

Question 1

moulding thermosets examples

Answer 1

compression, transfer, reaction injection

Question 2

moulding thermoplastics examples

Answer 2

rotational, injection

Question 3

moulding process

Answer 3

produce series of identical articles from hollow moulds

Question 4

compression moulding disadvantages

Answer 4

expensive tooling

Question 5

types of compression moulding

Answer 5

flash, flashless, controlled flash

Question 6

transfer moulding

Answer 6

injection and compression combined - transferred to another compartment

Question 7

transfer moulding advantages

Answer 7

better tolerances than compression moulding

Question 8

transfer moulding disadvantages

Answer 8

high tooling costs

Question 9

reaction injection moulding (RIM)

Answer 9

• two reactive liquids

- larger parts in smaller production runs

Question 10

rotational moulding

Answer 10

• rotated to cover mould - forms a ‘skin’ on inside

Question 11

rotational moulding advantages

Answer 11

cheap

Question 12

rotational moulding disadvantages

Answer 12

longer cycle times and no interior details

Question 13

injection moulding

Answer 13

like a syring into die

Question 14

types of injector in injection moulding

Answer 14

plunger type or screw type

Question 15

advantages of screw injector

Answer 15

better melting, good control of shot

Question 16

injection moulding - thermoset or thermoplastic

Answer 16

thermoplastic and some thermosets

Question 17

rotational moulding thermoset or thermoplastic

Answer 17

thermoplastic

Question 18

defects

Answer 18

avoid sinking and stress bending

Question 19

injection moulding advantages

Answer 19

high-rate production, good dimesional control

Question 20

injection moulding disadvantages

Answer 20

moulds expensive

Question 21

insert injection moulding

Answer 21

vertical machines - moulding around a part in a mould

Question 22

injection blow moulding

Answer 22

milk bottles