Name:
Class:
Date:
Copyright Cengage Learning. Powered by Cognero.
Page 1
1. What is the principal process for converting plastics into products?
a.
lamination
b.
injection molding
c.
liquid resin molding
d.
compression molding
ANSWER:
b
2. In all cases of injection molding, pelletized or granular materials must absorb enough heat to allow them to ____.
a.
vaporize
b.
cure
c.
set
d.
flow
ANSWER:
d
3. In the injection unit of an injection-molding machines (IMM), the action of the ____ determines the speed and
efficiency of plasticizing pellets.
a.
screw
b.
hydraulic motor
c.
end cap
d.
barrel
ANSWER:
a
4. When the material passes through the ____ zone of the screw, it should reach the desired melt temperature.
a.
melting
b.
feed
c.
metering
d.
transition
ANSWER:
c
5. A disadvantage of injection molding is that ____.
a.
it has low output rates
b.
molding machines are costly
c.
fillers and inserts cannot be used
d.
only one material may be injection molded
ANSWER:
b
6. What is the process in which two or more materials are injected into a mold cavity to produce an outer skin and an inner
core?
a.
fluid molding
b.
fiber molding
c.
co-injection molding
d.
sandwich molding
ANSWER:
c
Name:
Class:
Date:
Copyright Cengage Learning. Powered by Cognero.
Page 2
7. The primary goal of fluid injection during injection molding is to ____.
a.
increase rigidity
b.
promote curing
c.
improve flexibility
d.
control shrinkage
ANSWER:
d
8. What is an advantage of an electric IMM over a hydraulic IMM?
a.
it uses less power
b.
it is more automated
c.
it has a faster production time
d.
the parts are less costly
ANSWER:
a
9. The country that leads the United States in the use of all-electric IMMs is ____.
a.
Germany
b.
Malaysia
c.
Japan
d.
China
ANSWER:
c
10. The process in which several reactive chemical systems are mixed and forced into the molding cavity where a
polymerization reaction occurs is known as a ____.
a.
reinforced reaction injection molding (RRIM)
b.
isotropic molding
c.
resin transfer molding (RTM)
d.
reaction injection molding (RIM)
ANSWER:
d
11. Which industries are the major users of RIM products?
a.
computer housing
b.
automotive
c.
aeronautic
d.
boat hull
ANSWER:
b
12. An advantage of the RTM process is that ____.
a.
it minimizes material waste
b.
polymers may be reinforced
c.
good finishes can be expected
d.
there are fast cycle times for large products
ANSWER:
a
13. The process of compression molding is comparable to making ____.
Name:
Class:
Date:
Copyright Cengage Learning. Powered by Cognero.
Page 3
a.
coffee
b.
bread
c.
waffles
d.
pie
ANSWER:
c
14. Using a ____ process greatly reduces cycle time, eliminating the greatest drawback of compression molding.
a.
catalytic
b.
pre-mixing
c.
pre-heating
d.
screw-compression
ANSWER:
d
15. An advantage of compression molding is ____.
a.
tooling costs are low
b.
molding cycles are short
c.
no extra loading and unloading equipment required for automation
d.
complex shapes are easy to achieve
ANSWER:
a
16. An example of a product made by cold molding is ____.
a.
electrical insulator parts
b.
laminate sheets
c.
plates, bowls and other dishes
d.
vehicle dashboards
ANSWER:
a
17. An advantage of transfer molding is that the molten mass is ____when entering the mold cavity, allowing for fragile,
complex shapes with inserts or pins to be formed with accuracy.
a.
viscous
b.
premixed
c.
fluid
d.
preformed
ANSWER:
c