Deck 10: Molding Processes

Question 1

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 1

D

Question 2

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 2

A

Question 3

The process of compression molding is comparable to making ____.

A) coffee
B) bread
C) waffles
D) pie

Answer 3

C

Question 4

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

Question 5

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

Question 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

Question 7

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) t he parts are less costly

Question 8

The primary goal of fluid injection during injection molding is to ____.   

A) increase rigidity
B) promote curing
C) improve flexibility
D) control shrinkage

Question 9

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

Question 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)

Question 11

What is the principal process for converting plastics into products?    

A) lamination
B) injection molding
C) liquid resin molding
D) compression molding

Question 12

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

Question 13

Which industries are the major users of RIM products?

A) computer housing
B) automotive
C) aeronautic
D) boat hull

Question 14

The country that leads the United States in the use of all-electric IMMs is ____. 

A) Germany
B) Malaysia
C) Japan
D) China

Question 15

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

Question 16

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

Question 17

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