Your email address *

Your name *

Contact Name *

Contact telephone number *

Company *

Date *

1. A plastic that is once heated and formed into shape and then cannot be remelted is called a…
a)Thermoplastic material
b)Commodity plastic
c)Semi-crystalline plastic
d)Thermosetting plastic

2. The arrangement of the molecules in an amorphous thermoplastic could be described as…
a)Random
b)Regular
c)Aligned
d)Cross-linked

3. Which of the following materials is a semi-crystalline plastic?
a)PVC
b)Polypropylene
c)General purpose Polystyrene
d)ABS

4. What does the MFI (melt flow index) or MFR (melt flow rate) indicate?
a)Maximum extrusion temperature
b)Creep resistance
c)Flow behaviour under standard conditions
d)Flow behaviour at high shear rates

5. A hand held pyrometer could be used to…
a)Obtain pressure readings
b)Obtain die and melt temperatures
c)Obtain voltage readings
d)Obtain water flow readings

6. An effective Quality system would assure the customer that…
a)Non-conforming products remain within the production department
b)The quality of products supplied will be to the customer’s specification
c)All products will be thoroughly checked before delivery
d)All products will be 100% inspected before delivery

7. A spider line is….
a)A witness mark where melt fronts have met
b)A witness mark where two components have been joined
c)A witness mark from the construction of the screw
d)A witness mark from the mandrel

8. The process used to manufacture plastic materials is referred to as:-
a)Monomerisation
b)Pressurisation
c)Polymerisation
d)Plastification

9. When two or more materials flow into the die and produce a layered extrudate, this is referred to as being:-
a)Co-extrusion
b)Multi extrusion
c)Copolymerisation
d)Compounded extrusion

10. Along the length of a general purpose screw, the zone responsible for ensuring a homogeneous melt is called the:-
a)Metering zone
b)Compression zone
c)Decompression zone
d)Feed zone

11. The most important function of a screen pack is:-
a)To increase the extruder output rate
b)To create a stable back pressure within the barrel
c)To prevent any foreign materials from contaminating the extrudate
d)To reduce energy costs

12. The impact strength of materials used for the extrusion process can be improved by using:-
a)Reduced cooling rates
b)Faster haul off
c)Increased cooling rates
d)Faster output rates

13. When a die is re-assembled, to ensure that it does not leak, the most appropriate technique would be to:-
a)Tighten all bolts when the die is hot
b)Insert grease between the mating faces
c)Tighten all bolts when the die is cold
d)Ensure that the same fitter is used who dismantled the die

14. The average value for a set of sample results is referred to as the:-
a)Mean
b)Mode
c)Median
d)Range

15. Essential additives added to extrusion grades of PVC would be:-
a)Heat stabilisers
b)Lubricants
c)Anti-oxidants
d)All of the above

16. When purging out a heat sensitive material from an extruder, the most appropriate conditions to use are:-
a)Slow screw rotation speed
b)Low barrel temperatures
c)Introduce a specific purging compound
d)All of the above

17. What does S.W.L. mean?
a)Secure Weight Limit
b)Safe Weight Limit
c)Safe Working Load
d)Sure Way to Lift

18. Extrudate that does not meet the customer’s laid down specifications should be classified as:-
a)Variable
b)Scrap
c)Non-conforming
d)Repairable

20. An emergency stop button, if operated, must…
a)Prevent the screw from rotating
b)Interrupt all machine operations and switch off all drive motors
c)Automatically reset the machine
d)Automatically reset itself

19. The Health and Safety Executive recommends that machine operators complete safety checks on their extrusion lines:-
a)Weekly or after each new setup
b)Monthly
c)Annually
d)All of the above