Injection Molding

Question 1

is the expensive manufacturing process of making plastic

Answer 1

injection molding

Question 2

a manufacturing process capable of creating completely 3D plastic parts

Answer 2

injection molding

Question 3

injection molding is most commonly used in manufacturing ____

Answer 3

closures and tubs

Question 4

injection molding makes use of ____

Answer 4

thermoplastics

Question 5

injection molding is the leading method used to produce

Answer 5

caps and lids

Question 6

injection molding process is based on the ____ method

Answer 6

molten die casting

Question 7

melt volume or _____ accumulates at an empty space at the end of the screw

Answer 7

shot

Question 8

once the screw stops rotating, the melt is driven forward _____

Answer 8

mechanically or hydraulically

Question 9

4 steps in injection molding process

Answer 9

filling cycle, cooling cycle, mold open, eject part

Question 10

2 parts of injection molding machine

Answer 10

extruder section, clamp section

Question 11

The _____ should be able to eject a precise amount, or shot, of polymer into the mold

Answer 11

extruder section

Question 12

reciprocating screws are also called

Answer 12

ram-screw type

Question 13

must be large enough to hold the mold and provide adequate space for the part to be readily removed when the mold opens

Answer 13

clamp section

Question 14

are the reasons why injection molding has a high tooling cost

Answer 14

mold mass and complexity

Question 15

there must be enough _____ to hold the mold close against the pressure of the material being injected

Answer 15

clamping force

Question 16

would be prominent when there is too much injection force, and low clamping force

Answer 16

parting lines and flashes

Question 17

is an excess material attached to a molded, forged, or cast product

Answer 17

flashes

Question 18

if the injection force is too low and the shot size is too small, it will result to a _____

Answer 18

short shot problem

Question 19

occurs when a material does not completely fill the mold cavity

Answer 19

short shot

Question 20

clamping force is also called

Answer 20

tonnage

Question 21

the size of the extruders are named according to their

Answer 21

L/D ratio

Question 22

for injection molding, the size is dependent on the

Answer 22

injection capacity and clamping force

Question 23

what does 400-ton injection machine means?

Answer 23

400 tons of clamping force

Question 24

is a hollow form or matrix for giving a particular shape to sometheing

Answer 24

mold

Question 25

hollow or female part of the mold

Answer 25

cavity

Question 26

positive part or the male part of the mold

Answer 26

core

Question 27

mounted to the machine in a stationary position

Answer 27

cavity half

Question 28

2 main parts of the mold

Answer 28

cavity half, core half

Question 29

mounted on a sliding frame so the mold can open and close

Answer 29

core half

Question 30

use a melt-conveyance screw designed to provide reciprocal as well as rotary motion, combining the function of screw and piston

Answer 30

ram-screw-type (reciprocating screw)

Question 31

have a separate chamber and piston for injecting the molten polymer, allowing for faster injection of the plastic into the mold

Answer 31

screw plunger or two-stage machines

Question 32

wall thickness of the molded part is determined by the

Answer 32

space between the mold's core and cavity

Question 33

the small opening through which plastic melt enters the mold cavity

Answer 33

gate

Question 34

is the main channel through which the melt enters the mold

Answer 34

sprue

Question 35

are designed with material feed runners and gate systems that are insulated from the cooled mold cavity and core

Answer 35

runnerless or hot runner

Question 36

are often incorporated into the runner system to ensure that the plastic is kept on a hot, fluid state

Answer 36

auxiliary heaters

Question 37

is a channel that distributes molten plastic to various cavities in a multicavity mold

Answer 37

runners

Question 38

cools the molten polymer so that it solidifies

Answer 38

cooling channel

Question 39

cooling systems usually use

Answer 39

water or water-glycol mixture

Question 40

helps in physically ejecting the molded part

Answer 40

knock out pins and ejector plate

Question 41

might also be use in injection

Answer 41

compressed air

Question 42

is a part feature that prevents a mold from opening in a normal back-and-forth motion unless other pieces of mold metal are first removed

Answer 42

undercut

Question 43

these marks are mostly due to plastics' high expansion coefficients

Answer 43

sink marks

Question 44

occur where there is a substantial variation in the thickness of the plastic

Answer 44

sink marks